CHAPTER 5
REVIEW OF LITERATURE ON DAIRY CATTLE CROSSBREEDING IN THE TROPICS

The first attempts to introduce temperate cattle into the tropics took place more than 300 years ago. In places where native cattle were also kept importation of exotic stock naturally led to intentional as well as unintentional crossbreeding between the two groups, and local types of cattle of mixed origin were formed.

A more systematic effort to increase milk production in tropical countries by crossbreeding with European dairy breeds dates back to early this century. The first reports on the performance of such crosses appeared more than fifty years ago, and since then a large number of articles on this topic has been published. Particularly over the last twenty years many reports based on comprehensive sets of data, often collected in controlled experiments and analysed by modern statistical methods, have appeared.

In this review only reports which provide comparison between two or more crossbred groups, or between a cross and one or both parental breeds, have been included. Results based on very small sets of data have usually been omitted. When several reports have been published on the basis of parts of the same set of data preference has usually been given to the most recent report.

The traits of major importance in dairy cattle are viability, age at first calving, milk yield, milk composition, and calving interval. Age at first calving, milk yield, and calving interval have been reported in most studies, while records on viability and milk composition have rarely been reported. Whenever available information on all these traits has been included in the review. In some cases other traits, e.g. lactation length and length of dry period, have also been considered.

Throughout this review figures preceded by a ± sign are sampling standard errors, while figures in parenthesis indicate numbers of observations included in a mean. The terms significant and highly significant refer to probability levels P <0.05 and P <0.01, respectively.

5.1. INDIA

Early work on crossbreeding zebu (Bos indicus) and European type (Bos taurus) cattle in India was reviewed by Amble & Jain (1966, 1967) and Acharya (1970). Most of these early reports were based on small numbers of animals, and in many cases the statistical evaluation was inadequate to provide reliable results. In general the conclusion was that halfbreds were superior to all other grades.

5.1.1. Data from military farms.

Most of the extensive results reported on cattle crossbreeding in India are based on data from military farms. In these farms a policy of crossbreeding with Bos taurus breeds was adopted already at the beginning of this century. The breeds introduced were Shorthorn and Ayrshire, and later also Friesian. In some periods Bos taurus and Bos indicus bulls were used in alternating generations (criss-crossing).

Amble & Jain (1966, 1967) collected data from nine military farms over a period of 22 years (1934–55). All animals were sired by either zebu or European type bulls. Among the traits studied were age at first calving, first lactation yield, calving interval, and viability. In order to adjust for possible period-to-period variation due to environmental changes, constants were fitted to periods (five years) and grade groups (1/4 to 31/32 exotic inheritance) simultaneously. The analysis was carried out for each farm separately. The results presented were for about 1000 Sahiwal and Red Sindhi crosses with Friesian ⁽¹⁾ and Ayrshire. These results are summarised in Table 5.1.1.1.1.

TABLE 5.1.1.1.
PERFORMANCE OF DIFFERENT GRADES OF BOS TAURUS X BOS INDICUS (mainly Friesian (F) × Sahiwal) CROSSBRED COWS ON NINE MILITARY FARMS. Source: Amble & Jain, (1966).

It was concluded that with respect to production characters halfbreds and five-eights excelled all other grades, irrespective of breed used in the crosses. The same grades were the best in viability.

Katpatal (1970) studied records on 521 Sahiwal × Holstein-Friesian cows (1447 lactations) from one military farm. The proportion of Holstein-Friesian inheritance ranged from 5/16 to 15/16. Estimates by least squares indicated that intermediate grades were superior in growth rate as well as in milk production. A quadratic regression function, fitted to the least squares means showed an optimum at 5/8 Holstein-Friesian ⁽¹⁾ inheritance with respect to milk yield. The author used multiple regression technique to separate heterotic effects from additive breed effects, and estimated the amount of heterosis for milk yield in F₁ crosses at 35–45 per cent.

Dhillon & Jain (1977) computed average milk yield per day of calving interval for 97 Sahiwal cows and 648 Holstein-Friesian (HF) x Sahiwal crosses. The results obtained for Sahiwal, 1/4 HF, 1/2 HF, 5/8 HF, and 3/4 HF were 4.52, 5.11, 6.40, 6.58, and 5.98 kg, respectively. Differences between 1/2 HF, 5/8 HF, and 3/4 HF were not significant.

Bhat et al. (1978) used data from eight military farms (five of these were included also in the study of Amble & Jain, 1966) over 30 years (1939–68). Only pure bred sires had been used. Records on about 700 Sahiwal cows and about 1800 Sahiwal × Holstein grades (ranging from 1/16 to 63/64 Holstein ancestry) were utilized. Traits studied were age at first calving, first lactation yield, lactation length, calving interval, service period, and dry period. Least squares constants were estimated for a model which included effects of farm, period, season of calving, and proportion of Holstein. Age at first calving decreased with increasing proportion of Holstein inheritance up to 50%, thereafter no clear trend was seen. First lactation yield and lactation length increased up to 38/64 Holstein grade. The lowest age at first calving and the highest lactation yield was, however, observed for 63/64 Holstein (about 20 cows).

On the basis of the same data, Taneja & Bhat (1978) tried to separate additive and heterotic effects by regressing the least squares means obtained for the various grades on the proportion of Holstein inheritance of sire and dam, and proportion of heterozygosity (a shorter version of this study was presented by Taneja & Bhat, 1974). In addition to the traits mentioned above body weights from birth to first calving were also studied. Results are presented in Table 5.1.1.2.

(l) Throughout this review the terms Friesian, Holstein, and Holstein-Friesian are used as used in the report reviewed.

TABLE 5.1.1.2.
PARTIAL REGRESSION COEFFICIENTS OF VARIOUS TRAITS ON PROPORTION OF HOLSTEIN GENES IN SIRE, DAM, AND HETEROZYGOSITY (all in fractions of 32) IN HOLSTEIN × SAHIWAL CROSSES. Source: Taneja & Bhat (1978).

Effects of proportion of Holstein inheritance in sire and dam were significant for all body weights and first lactation yield. Breed of sire had significant influence also on age at first calving and first lactation length, while length of first service period, first calving interval, and first dry period were not significantly affected by proportion of Holstein in sire or dam. Significant effects of heterosis were found for weight up to six months, age at first calving, length of first calving interval and length of first dry period. For first lactation milk yield a non-significant positive effect of heterosis was observed, corresponding to about 5% heterosis in F₁. A significant difference between regression on breed of sire and breed of dam (which would indicate that the breeds differed in maternal effects) was found for only one out of twelve traits examined.

Rao & Nagarcenkar (1979) collected data on Friesian, Jersey and Brown Swiss cows and their crosses with zebu breeds (Sahiwal, Tharparkar, Hariana, Red Sindhi, Rathi) at four military and five civil farms in the Indo-Gangetic plains. All Brown Swiss crosses were from the National Dairy Research Institute, Karnal (see below), and for Jersey only two genetic groups (50 and 100% Jersey) were represented. Traits studied were first lactation yield (total and 300 days), lactation length, and calving interval. Least squares analysis was used, and the model included effects of farm, period (four periods from 1960 to 1975), season, and genetic group. An extract of results obtained for Friesian and Friesian crosses is presented in Table 5.1.1.3.

TABLE 5.1.1.3.
FIRST LACTATION PERFORMANCE OF FRIESIAN (F) AND FRIESIAN CROSSES IN THE INDO-GANGETIC PLAINS. Source: Rao and Nagarcenkar (1979).

In milk yield all grades with less than 50% Friesian inheritance were significantly inferior to all grades above this level. The highest yield was observed for purebred Friesians, followed by 50% Friesian (presumably F₁). A significant effect of grade was found also for lactation length, but not for calving interval.

Rao & Taneja (1980) studied data on more than 3500 Holstein-Friesian × zebu (mostly Sahiwal) crossbred cows on ten military farms in Northern and Central India (including the four which provided data for Rao & Nagarcenkar 1979) and six military farms in Southern India. The records were made from 1967 to 1975. Traits examined were age at first calving, first lactation (305 days) milk yield, first lactation length, and first calving interval. Least squares techniques were used, and the model included farm, year, month, and parity of dam, in addition to genetic group. Results for Holstein-Friesian × Sahiwal crosses are summarized in Table 5.1.1.4.

TABLE 5.1.1.4.
PERFORMANCE OF HOLSTEIN-FRIESIAN (HF) × SAHIWAL CROSSES AT MILITARY FARMS IN NORTHERN AND SOUTHERN INDIA. Source: Rao & Taneja (1980)

In both regions 1/2 Holstein-Friesian was significantly superior to all other groups in first lactation milk yield. Further, 3/8 Holstein-Friesian had the lowest yield in both regions. For the other traits no definite trend could be seen, but 1/2 Holstein-Friesian had the lowest age at first calving. Significant interaction between farms and genetic groups was found for first lactation length in both regions, and for age at first calving and calving interval in the northern region, while no such inter action was found for first lactation milk yield. Interactions between genetic groups and herd levels were unimportant.

In the same report (Rao & Taneja, 1980) results from crossbreeding of Red Sindhi with Holstein-Friesian and Red Dane at Bangalore Military Farm were also presented. These results are given in Table 5.1.1.5.

Differences among the four genetic groups were small except for calving interval, which was longer in the two groups with 75% exotic inheritance than in the two F₁ groups. There was no significant difference between the Holstein-Friesian and the Red Dane F₁ crosses.

TABLE 5.1.1.5.
PERFORMANCE OF HOLSTEIN-FRIESIAN (HF) AND RED DANE (RD) CROSSES WITH RED SINDHI AT BANGALORE MILITARY FARM. Source:Rao & Taneja (1980)

Data on Sahiwal cows and Holstein-Friesian × Sahiwal crosses at five military farms in Northern India over more than 30 years (1942–1976) were used by Matharu & Gill (1981) to compare lifetime production and reproduction efficiency of the various genetic groups. Cows with 5/8 Holstein-Friesian inheritance had the highest lifetime production and also the highest milk yield per day of productive life, while milk yield per day of total life was highest in the halfbreds.

Deshpande & Bonde (1982, 1983 a, b) examined first lactation milk records of 1346 Friesian x Sahiwal crosses at four military farms in the southern region (the same farms were included also in the study by Rao & Taneja, 1980). The records were collected from 1969 to 1978. The data were analysed by least squares techniques according to a model including effects of farm, period (1969 to 1973 vs. 1974 to 1978), season (four seasons) and grade. Least squares means for various grades wi1 respect to first lactation yield, milk yield per day of age at second calving, and first calving interval were as reported in Table 5.1.1.6.

TABLE 5.1.1.6.
FIRST LACTATION MILK YIELD IN FRIESIAN (F) X SAHIWAL CROSSBREDS. Source: Deshpande & Bonde (1982, 1983 a, b)

The highest milk yield was observed in 1/2 F and 5/8 F; when the proportion of Friesian inheritance increased above this level there was a slight decrease in yield. Length of calving interval did not differ significantly among the crosses, but grades with intermediate levels of Friesian inheritance had the shortest calving intervals.

Military farms were the source of data also in a study by Ganpule & Desai (1983), who compared the efficiency of milk production in various Sahiwal × Holstein-Friesian crosses. Milk production efficiency, defined as milk yield per day of life up to end of 5th lactation, increased almost linearly with increasing proportion of Holstein-Friesian inheritance.

5.1.2. Bilateral projects

The Red Dane bulls used at Bangalore Farm (Rao & Taneja, 1980, see above) originated from an importation of Danish cattle to the Indo-Danish Project in the Bangalore area. Results obtained at this project were reported by Madsen (1976). At the project farm purebred Red Dane cows born in India were found to produce less milk than the cows imported from Denmark. A milk recording scheme provided data on the performance of various genetic groups in the villages. For groups which were represented by a reasonably large number of animals results are given in Table 5.1.2.1.

TABLE 5.1.2.1.
PERFORMANCE OF RED DANE (RD) CROSSES IN VILLAGES IN THE BANGALORE AREA. Source: Madsen (1976)

Most improved local cattle were crossbreds between European and local cattle, but few were first crosses. As a group they were assumed to carry approximately 50% Bos taurus genes. Although they had a fairly satisfactory milk yield, they were outproduced by the Red Dane crossbreds. The highest milk production and the shortest calving interval was observed for the Red Dane crosses with Red Sindhi.

Brown Swiss was the source of exotic inheritance in the Indo-Swiss projects in Kerala and Punjab. The project in Kerala started in 1963 with 30 bulls and 45 cows imported from Switzerland. The local stock was nondescript cattle from the area, showing traces of improved Indian dairy breeds (Red Sindhi) as well as of European breeds. Results were reported by Nair (1973, 1974) and more recently by Chacko (1983), and are summarized in Table 5.1.2.2.

TABLE 5.1.2.2.
PERFORMANCE OF VARIOUS GENETIC GROUPS IN THE INDO-SWISS PROJECT, KERALA.

Cows with 50 to 75 per cent Brown Swiss inheritance produced about three times as much milk as the local cows, and also slightly more than purebred Brown Swiss. All crossbred groups were younger than both parental breeds at first calving, and had shorter calving intervals.

The Indo-Swiss Project in Patiala, Punjab, was initiated in 1971. Fifteen Brown Swiss bulls and 86 females were imported from Switzerland in two batches, and used for crossbreeding with Sahiwal; ten American Brown Swiss females were also incorporated in the herd. Records collected up to 1978 were evaluated and results presented by Menzi et al. (1982) (Table 5.1.2.3).

Table 5.1.2.3.
DAIRY PERFORMANCE OF VARIOUS GENETIC GROUPS IN THE INDO-SWISS PROJECT, PUNJAB. Source: Menzi et.al. (1982)

Brown Swiss × Sahiwal crosses (F₁) produced twice as much milk as purebred Sahiwal, and also more than purebred Brown Swiss. A comparison between imported and locally-born Brown Swiss cows showed that the imported cows were superior in milk yield, while those born in India were younger at first calving and had shorter calving intervals.

5.1.3. National Dairy Research Institute

A large scale crossbreeding experiment with cattle was initiated at the National Dairy Research Institute, Karnal, in 1963. Sahiwal, and a few Red Sindhi, females were mated to Brown Swiss bulls (imported semen) to produce an F₁ generation. At later stages backcrossing to Brown Swiss and inter se mating of F₁ took place. Data collected up to 1976 were examined by Taneja & Chawla (1978 a, b). The former study was based on records of Red Sindhi crosses. An extract of results for three genetic groups is given in Table 5.1.3.1. Differences between groups were significant only for age at first calving. Numbers of animals included in the study were not reported.

Table 5.1.3.1.
LEAST SQUARES MEANS FOR VARIOUS TRAITS IN BROWN SWISS (BS) × RED SINDHI CROSSBREDS AT NDRI, KARNAL. Source: Taneja & Chawla (1978 a).

In the later paper (1978 b) results from the investigation on Sahiwal crosses were presented. This report also included records on the purebred Brown Swiss cattle (Braunvieh) at the Indo-Swiss Project at Patiala (see above). Among the traits studied were age at first calving, first lactation milk yield (actual and 305 days), first lactation length, and calving interval. Least squares techniques were used to eliminate possible time trends. The means obtained for Sahiwal, F₁, F₂, reciprocal backcrosses, and pure Brown Swiss are given in Table 5.1.3.2.

Table 5.1.3.2.
LEAST SQUARES MEANS FOR VARIOUS TRAITS IN BROWN SWISS (BS) × SAHIWAL CROSSBREDS AT NDRI, KARNAL. Source: Taneja & Chawla (1978 b).

The authors used the estimated least squares means as dependent variables in a multiple regression analysis in which proportion of Brown Swiss inheritance in sire and dam, and proportion of heterozygosity were the independent variables. The analysis (Table 5.1.3.3) showed widely different regression coefficients for breed of sire and breed of dam, suggesting different maternal effects of the two breeds (standard errors of estimates were not reported). Heterosis, estimated as twice the difference between F₁ and F₂ amounted to 1160 kg for milk yield. This was 37% of the F₂ mean (or 58% of estimated midparent mean). When estimated from the multiple regression analysis heterosis for milk yield was 735 kg (35% of midparent mean). Substantial amounts of heterosis were observed also for age at first calving and calving interval.

TABLE 5.1.3.3.
PARTIAL REGRESSION COEFFICIENTS OF VARIOUS TRAITS ON BREED OF SIRE, BREED OF DAM (PROPORTIONS OF BROWN SWISS) AND HETEROZYGOSITY (ALL IN FRACTIONS OF 8) IN BROWN SWISS × SAHIWAL CROSSBREDS. Source: Taneja & Chawla (1978 b).

Rao & Nagarcenkar (1979, see above) used data from the same project, but slightly larger numbers of records. Results (least squares means) are presented in Table 5.1.3.4.

TABLE 5.1.3.4.
FIRST LACTATION PERFORMANCE OF BROWN SWISS (BS) X SAHIWAL CROSSES AT NDRI, KARNAL. Source: Rao & Nagaroenkar (1979).

The ranking of different genetic groups was as in Taneja & Chawla (1978 b), but F₂ came out slightly worse and 3/4 BS slightly better. The set-back from F₁ to F₂ was nearly 700 kg of milk. For lactation length and calving interval changes from F₁ to F₂ were non-significant, but in the undesirable direction also for these traits.

Bhatnagar et al. (1981) summarized records of Brown Swiss crosses at NDRI, Karnal, up to the end of 1980. The review (Table 5.1.3.5) confirmed the large decline in milk yield from F₁ to F₂ found in the studies mentioned above. From F₂ to F₃ no further decrease was observed. The backcrosses to Brown Swiss bulls (3/4 BS) were in general intermediate between F₁ and F₂ and would even after discounting for expected loss of heterosis from the first to subsequent generations (inter se mating of 3/4 BS) be predicted to outyield F₂.

TABLE 5.1.3.5.
PERFORMANCE OF BROWN SWISS CROSSES AT NDRI, KARNAL, 1966–80. Source: Bhatnagar et al. (1981).

1) From mating of F₁ × F₂ etc.

Sharma et al. (1983) reported yields and percentages of fat and solids-not-fat (SNF) for various genetic groups in the same experiment. Differences in fat and SNF percentages were small and nonsignificant. The ranking of various crosses with respect to fat and SNF yields was therefore similar to that for milk yield (see above). F₂ produced 27% less fat and SNF than F₁.

In another project at NDRI, Karnal, bulls of three European type breeds (Friesian, Brown Swiss, Jersey) were crossed with Tharparkar cows. Females of the three F, crosses were mated with Friesian bulls to produce offspring with 75% European inheritance. Results are summarized by Nagarcenkar et al.(1982) and by Nagarcenkar & Rao (1982) (Table 5.1.3.6).

TABLE 5.1.3.6.
PERFORMANCE OF FRIESIAN (F), BROWN SWISS (BS) AND JERSEY (J) CROSSES WITH THARPARKER (T) AT NDRI, KARNAL. Sources: Nagarcenkar & Rao (1982), Nagarcenkar et al.(1982).

Among F₁ crosses Friesian had the highest and Jersey the lowest milk yield, and their daughters sired by Friesian bulls ranked similarly. Milk yield decreased and calving interval increased when the proportion of exotic inheritance increased from 50 to 75%. There was also a marked increase in calf mortality (Rao & Nagaroenkar, 1980).

Jadhav & Bhatnagar (1983) compared dairy merits of different crossbred groups in the NDRI herd. The groups compared were Holstein × Tharparkar (HT), Holstein × Sahiwal (HS), Brown Swiss × Tharparkar (BT), Brown Swiss × Sahiwal (BS), and Jersey x Tharparar (JT). Whether the cows were F₁, F₂, or a combination of the two, was not reported, only that they were halfbreds. Number of cows per group ranged from 12 to 39. The data comprised records for the first four lactations. Dairy merit was defined as energy in milk produced in per cent of energy consumed, the latter being predicted from fat-corrected milk yield, body weight, and change in body weight during lactation. The overall least squares means obtained were 28.8 ±0.3, 28.8 ± 0.5, 26.0 ± 0.4, 26.6 ±0.1, and 26.2 ± 0.3, for HT, HS, BT, BS, and JT, respectively. It was concluded that Holstein crosses (HT and HS combined) were significantly superior to Brown Swiss crosses (BT and BS combined) and JT crosses in dairy merit.

5.1.4. Haringhata Livestock Farm

At Haringhata Livestock Farm (near Calcutta) crossbreeding work began in 1957–58, when Hariana and nondescript local (Deshi) females were mated to three Jersey bulls, two from U.S. and one from Australia (Bhattacharya & Guha, 1966). Later this project was extended to the adjacent Kalyani Farm and continued with Jersey and Friesian semen obtained from Australia. Data collected up to 1974 on Hariana and Jersey × Hariana crossbreds were analysed by Parmar et al. (1980). The study included records on 671 F₁ and 261 F₂ cows (sired by 17 Jersey and 58 F₁ bulls, respectively) in addition to 149 purebred Hariana. The traits studied were age at first calving, lactation (305 days) milk yield, calving interval, milk yield per day of calving interval, and dry period. Least squares means for various genetic groups are given in Table 5.1.4.1.

TABLE 5.1.4.1.
DAIRY PERFORMANCE OF HARIANA AND JERSEY X HARIANA CROSSES AT HARINGHATA AND KALYANI. Source: Parmar et al. (1980).

Both crossbred groups were considerably younger than Hariana at first calving, and had higher milk yields, shorter calving intervals, and shorter dry periods. Age at first calving was slightly higher (1.9 months) for F₂ than for F₁, milk yields were lower (about 20%), and calving intervals slightly longer. Heterosis, estimated as twice the difference between F₁ and F₂, and expressed in percent of F₁ means, was -12, -5, and 42 per cent, for age at first calving, calving interval, and lactation (305 days) milk yield, respectively.

In 1968 a large scale cattle crossbreeding experient was initiated at Haringhata. The experiment formed part of the project Improvement of Milk Production in the Calcutta Area, which was sponsored by UNDP. Foundation cows of the Hariana breed were mated by artificial insemination to Friesian, Brown Swiss, and Jersey bulls from U.S. and (in the case of Friesian and Jersey) U.K. of the resulting F₁ females half were bred to an F₁ bull from the same cross, and the other half to a bull of the paternal breed. The production of F₁ continued in order to have contemporary groups of F₁, F₂, and backcrosses (3/4 exotic inheritance) of each of the three exotic breeds. Records collected at Haringhata from 1959 to 1977 were evaluated by Bala & Nagarcenkar (1981). Results are given in Table 5.1.4.2.

TABLE 5.1.4.2.
DAIRY PERFORMANCE OF DESHI, HARIANA AND THEIR CROSSES WITH FRIESIAN, BROWN SWISS, AND JERSEY AT HARINGHATA. Source: Bala & Nagarcenkar (1981).

The Friesian crossbreds excelled in milk yield, but were slightly older at first calving and had slightly longer calving intervals than Jersey crosses. A serious decline in performance from F₁ to F₂ was observed in both crosses: F₂ were about eight months older at first calving and produced about 30% less milk. They had also much longer calving intervals. Purebred Friesians and Jerseys were better than any of the crosses, but the pure exotics were kept in separate units, and preferential treatment can not be excluded. In milk yield F₁ values were 15 to 20% above midparent means.

5.1.5. All-India Coordinated Research Project on Cattle.

In 1968 a project entitled Behaviour Pattern of Zebu Crossbreds was initiated at the Indian Veterinary Research Institute (IVRI), Izatnagar, and Hariana Agricultural University (HAU), Hissar. The project involved crossbreeding of the Hariana breed with Holstein, Brown Swiss and Jersey. Subsequently the project was renamed the “All India Coordinated Research Project on Cattle” (AICRPC). In 1970 the project was extended to three more institutions: Andra Pradesh Agricultural University (APAU), Lam; Mahatma Phule Krishi Vidyapeeth (MPKVP), Rahuri; Jawaharlal Nehru Krishi Viswa Vidyalaya (JNKVV), Jabalpur.

The zebu stock was Ongole at the first centre and Gir at the two others. In 1973 the crossbreeding experiment at Haringhata (CBP) was merged with the AICRPC, thus bringing the number of centres to six.

The original mating plan was to produce four types of crossbreds for each of the three exotic breeds:

1. First crossbred generation, F₁.

2. Backcross to the paternal breed.

3. F₂, by mating males and females from the same F₁ cross inter se.

4. Three-breed crosses, by mating males and females from two different F₁ crosses in all (six) possible combinations.

This plan of mating was, however, changed several times. At an early stage it was decided to delete the genetic groups II, III and IV (see above). Instead, F₁ females should be mated to a bull of one of the two other exotic breeds, to produce three-breed crosses with 75% exotic inheritance (two exotic breeds). Later, the two crosses combining Brown Swiss and Jersey were omitted. The number of second generation crosses was thus reduced to four. Finally, males and females of each of these three-breed crosses were to be mated inter se.

At two of the centres, Rahuri and Jabalpur, both with Gir as foundation stock, the mating plan was modified further, as no Brown Swiss F₁ crosses were produced. Consequently only three genetic groups will be present in the second crossbred generation. In 1980, also inter se mating of F₁ males and females from the same cross to produce F₂ groups was taken up again. Results extracted from the project’s annual report for 1982/83 are presented in Tables 5.1.5.1. and 5.1.5.2.

TABLE 5.1.5.1.
PERFORMANCE OF VARIOUS Fl CROSSBREDS IN THE ALL INDIA COORDINATED RESEARCH PROJECT ON CATTLE (AICRPC). Source: Indian Council of Agricultural Research, 1983. (Project Coordinator's Report 1982–83).

1) First lactation milk yield in 305 days or less except for IVRI (complete first lactation) and CBP (all lactations pooled).

2) First calving interval except for CBP and MPKVP, where all calving intervals were pooled.

3) Source: Parekh, 1982.

The results in F₁ were very consistent across units. Brown Swiss crosses were the oldest at first calving in all the four units where they were represented, while Jersey crosses were the youngest at four out of the six units. At all units Friesian crosses had the highest and Jersey crosses the lowest milk yield, Brown Swiss crosses being almost midway between the two others. Calving intervals were always shorter for Jersey crosses than for the others, differences between Friesian and Brown Swiss crosses being small and inconsistent.

In three-breed crosses differences among genetic groups were as expected smaller than in F₁. In general, crosses sired by Friesian bulls had the highest milk yield, while crosses by Jersey bulls were the youngest at first calving and had the shortest calving intervals.

TABLE 5.1.5.2.
PERFORMANCE OF VARIOUS THREE-BREED CROSSES IN THE ALL-INDIA COORDINATED RESEARCH PROJECT ON CATTLE (AICRPC). Source:Indian Council of Agricultural Research, 1983. (Project Coordinator's Report 1982–83.) (For notes, see Table 5.1.5.1).

Comparisons between F₁ and three-breed crosses are less reliable as the two groups necessarily were non-contemporaries. However, the three-breed crosses were on average slightly older at first calving and had also slightly longer calving intervals, whereas milk yields were rather similar. The Friesian F₁ crosses produced more milk than any of the three-breed crosses at all units except one.

A least squares analysis, taking account of year and season effects, but based on smaller numbers of records, led to similar results.

Kaikini et al. (1981 a, b, c, d) studied reproductive traits of 96 Friesian × Gir and 84 Jersey × Gir crosses in the Rahuri unit in more detail. Incidences of repeat breeding and reproductive disorders did not differ much in the two crosses (22.0 vs. 19.9% and 36.5 vs. 32.1%, respectively). Differences were slight also for age at maturity (413 vs. 402 days), and age at first service (454 vs. 444 days). However, at first calving Friesian crosses were about 1 month older than Jersey crosses (812 and 766 days, respectively ).

As to viability, Parekh & Singh (1981) found no significant difference in mortality rates between Friesian × Gir and Jersey × Gir crosses in the Jabalpur unit.

5.1.6 Miscellaneous projects.

The crossbreeding work at Haringhata Farm, West Bengal (see above) was extended also to the area around the farm. Panda & Sadhu (1983) collected milk records of F₁ crosses of Hariana and Deshi (local) cows with Holstein and Jersey bulls. The cows were kept under rural conditions, and fed paddy straw ad lib. with a supplement of a concentrate mixture according to recommendations (no details given). The means of first lactation and all lactations are entered in Table 5.1.6.1.

TABLE 5.1.6.1.
MILK YIELD OF HARIANA AND DESHI (LOCAL) CROSSES WITH HOLSTEIN AND JERSEY UNDER RURAL CONDITIONS AROUND HARINGHATA FARM, WEST BENGAL. Source: Panda & Sadhu (1983).

Daughters of Hariana dams produced more milk than daughters of Deshi dams, and Holstein crosses more than Jersey crosses. Both differences were highly significant. All crosses had considerably higher yields than the same crosses at Haringhata (Table 5.1.4.2).

Chaudhary & Chaudhary (1984) studied lifetime performance of 101 Rathi cows and Red Danish x Rathi crosses in Rajastan. The crosses were about 15 months younger at first calving and produced 70% more milk in their first lactation (2319 vs. 1418 kg), but their superiority decreased with increasing age.

Duc & Taneja (1984) examined records on production and reproduction traits in Hariana, Holstein-Friesian and Jersey cows along with Holstein-Friesian × Hariana and Jersey × Hariana crosses at the Governent Livestock Farm Hissar, Hariana. The exotic stock originated from Australia. All groups were treated similarly, with the exception that calves were used to stimulate milk let-down in Hariana and crosses, but not in pure exotics. Traits studied were age at first calving, first lactation milk yield (305 days) and first calving interval. The results are given in Table 5.1.6.2.

TABLE 5.1.6.2.
PERFORMANCE OF PUREBRED AND CROSSBRED CATTLE AT GOVERNMENT LIVESTOCK FARM HISSAR, HARIANA. Source: Due & Taneja (1984).

Holstein-Friesian and Jersey were about 18 months younger than Hariana at first calving, produced twice as much milk, and had shorter calving intervals. Crossbreds were closer to the exotic breed in age at first calving, but almost midway between the parental breeds in the other traits. Holstein-Friesian were older than Jersey at first calving, produced more milk and had longer calving intervals, and the F₁ crosses of the two breeds ranked similarly.

5.2. OTHER COUNTRIES IN ASIA

5.2.1. Sri Lanka

European cattle were brought to Sri Lanka by the early Dutch settlers some 300 years ago (Buvanendran & Mahadevan 1975), and were crossed with local cattle. Some of the present types of cattle are supposed to be descended from these early importations. Herds of European breeds are also maintained at government farms in the more favourable parts of the country.

Buvanendran & Mahadevan (1975) reviewed three crossbreeding experiments involving Bos indicus and Bos taurus cattle. The first experiment was initiated in 1953 and was carried out at Karagoda-Uyangoda in southern Sri Lanka. Local (Sinhala) females were crossed with Friesian and Jersey bulls, and the resulting F₁ progenies were mated inter se to produce F₂ of both breed crosses. In the case of Jersey some F₁ females were backcrossed to Jersey bulls. The results obtained during the periods 1956–66 (Wijeratne, 1970) and 1968–73 are summarized in Table 5.2.1.1.

TABLE 5.2.1.1.
PERFORMANCE OF SINHALA AND THEIR CROSSES WITH FRIESIAN AND JERSEY AT KARAGODA-UYANGODA, SRI LANKA. Sources: Wijeratne (1970), Buvanendran & Mahadevan (1975).

F₁ crosses showed a remarkable increase in milk yield over the indigenous cows. The crosses had also longer lactations, while there was no important difference in calving intervals. Friesian crosses produced 30–40 per cent more milk than Jersey crosses. However, the most striking feature of the results is the drastic deterioration from F₁ to F₂ in both breed crosses. No further decline was observed from F₂ to F₃ (Friesian crosses only). Jersey backcrosses (3/4 J) were intermediate between F₁ and F₂.

The second experiment was carried out at Undugoda in the central part of the country (coconut triangle). Red Sindhi cows were mated to Jersey bulls to produce F₁. Subsequently F₂ and animals with 3/4 and 5/8 Jersey inheritance were also produced. The cows were kept in the stall and fed grass throughout the year. Records collected up to 1971 were evaluated by Buvanendran & Mahadevan (1975) and Buvanendran (1974, 1977) (Table 5.2.1.2).

TABLE 5.2.1.2.
PERFORMANCE OF RED SINDHI × JERSEY CROSSES AT UNDUGODA, SRI LANKA. Sources: Buvanendran (1974), Buvanendran & Mahadevan (1975), Buvanendran (1977).

Again a drastic decline in milk yield from F₁ to F₂ was observed, and this was accompanied by an increase in calving interval. The backcrosses (3/4 J) were close to F₁ in milk yield, but were very old at first calving and had long calving intervals.

In the third experiment, which took place at Wirawila in the dry zone, Sinhala females were first mated to Red Sindhi bulls. The crossbred females (ranging from 1/2 to 7/8 Red Sindhi inheritance) were then mated to Shorthorn or Jersey bulls. Buvanendran & Mahadevan (1975) reported results obtained up to 1974 (Table 5.2.1.3).

TABLE 5.2.1.3.
PERFORMANCE OF VARIOUS CROSSES AT WIRWILA, SRI LANKA. Source: Buvanendran & Mahadevan (1975).

Crosses with the European breeds produced about 50% more milk than Red Sindhi and Red Sindhi x Sinhala crosses. They had also longer lactations and shorter calving intervals.

5.2.2. Thailand

Madsen & Vintner (1975) reported results of crossbreeding at the Thai-Danish Dairy Farm. The foundation (zebu) females were classified into three groups, namely:

1. Native cattle

2. Improved native cattle, mainly White zebu from Burma

3. Indian dairy breeds (Sahiwal and Red Sindhi)

Males and females of Red Danish Cattle were imported in 1962–63 and again in 1970. A few Brown Swiss and Jersey crosses were also included in the herd. The mating programe was essentially grading with Red Danish bulls, but from 1967 onwards some Indian dairy and crossbred (Indian dairy × Red Danish) bulls were also used. Records collected up to 1973 were analysed by least squares techniques. The traits studied were mortality, age at first calving, milk and milk fat yields (first and second lactation), and calving interval. Results are summarized in Tables 5.2.2.1 and 5.2.2.2.

TABLE 5.2.2.1.
PERFOFMNCE OF PUREBRED AND CROSSBRED DAIRY CATTLE AT THE THAI-DANISH DAIRY FARM, THAILAND. MORTALITY AND REPRODUCTIVE TRAITS. Source: Madsen & Vintner (1975).

TABLE 5.2.2.2.
PERFORMANCE OF PUREBRED AND CROSSBRED DAIRY CATTLE AT THE THAI-DANISH DAIRY FARM, THAILAND. MILK AND FAT YIELDS. Source: Madsen & Vintner (1975).

Mortality rates were low in F₁ crosses (50% Red Dane) and very high in Red Danish Cattle and high grades. However, the highest rate of calf mortality was observed in the Indian dairy breeds. The F₁ crosses also were the youngest at first calving and had the shortest calving intervals. Milk yields increased with increasing proportion of Red Dane inheritance, while fat percentage showed a slight opposite change. F₁ crosses between Red Danish Cattle and Indian dairy breeds were 20 to 30% above the mean of the parental breeds in milk and fat yields. Red Danish cows born in Denmark (imported as heifers) had on average about 50% higher first lactation yields than Red Danish cows born in Thailand, but this superiority was lost in second lactation.

5.2.3. Pakistan

Most of the specialised dairy breeds of Bos indicus, like Sahiwal, Tharparkar, and Red Sindhi, have their origin in present Pakistan. This might explain why crossbreeding for milk production has not been more widely studied in this country.

Shah et al. (1982) reported results from a crossbreeding experiment at the Livestock Experiment Station Bahadarnagar. Sahiwal females and their F, crosses with Friesian and Jersey were compared under similar managemental and environmental conditions. In addition to milk yield fat content was also recorded. Age at first calving or other reproductive traits were not reported. Results are summarized in Table 5.2.3.

TABLE 5.2.3.
FIRST LACTATION PERFORMANCE OF PUREBRED SAHIWAL AND THEIR CROSSES WITH FRIESIAN AND JERSEY AT LIVESTOCK EXPERIMENT STATION BAHADARNAGAR, PAKISTAN. Source: Shah et al. (1982).

The crossbred cows produced nearly twice as much milk and milk fat as the purebred Sahiwals. The difference between the two crossbred groups was small and non significant. Jersey crosses had significantly higher fat content than Friesian crosses.

Ishaq et al. (1981) compared 24 pure Sahiwal and 24 Swedish Red and White × Sahiwal heifers. The crossbreds calved at a younger age (815 vs. 1035 days), produced more milk per day (8.5 vs. 4.3 kg), and had longer lactations (329 vs. 231 days) than the purebreds. Observations on pulse and respiration rate showed that the crosses were significantly less adapted to heat stress than the native Sahiwal.

5.2.4. Iraq

At Abu-Ghraib Experiment Station (near Baghdad) the indigenous Jenubi cattle were upgraded with Friesian. Records collected from 1969 to 1976 were analysed by Al-Rawi & Said (1980). Least square means for milk yields in 704 lactations were:

All crosses produced 50 to 80% more milk than Jenubi. The highest yield was obtained for 3/4 Friesian.

5.3. AFRICA

5.3.1. Egypt

From 1926 onwards several Bos taurus breeds, including Friesian, Shorthorn, Jersey, and Guernsey, have been introduced to Egypt. The imported animals have been used both for establishing pure exotic herds and for upgrading of local stock.

At El-Sirw Experimental Farm (Animal Production Research Institute) Bos taurus breeding was initiated in 1947 as two males and 16 females of Dairy Shorthorn were imported from Britain. After a period of upgrading of the native cattle, the policy was to breed males and females of the same grade inter se. Records collected up to 1974 were examined by Fahmy et al. (1976). Results are summarized in Table 5.3.1.

TABLE 5.3.1.
PERFORMANCE OF NATIVE CATTLE, DAIRY SHORTHORN, AND THEIR CROSSES AT EL-SIFW EXPERIMENTAL FARM, EGYPT. Source: Fahmy et al. (1976).

(1) In the table age at first calving of native females was reported at 3.07 years (= 36.8 mths.). The present entry, which is taken from the text of the same report (3.63 years = 43.6 mths.), appears to be the correct figure.

(2) No. of cows - No. of lactations.

Dairy Shorthorn and all crosses calved at a considerably younger age than native females, and produced nearly twice as much milk per lactation. Differences among various crosses were small, and most crosses had a slightly higher milk production than purebred Shorthorn.

On the other hand, native cows had slightly shorter calving intervals than Shorthorn and their crosses. The authors concluded that pure breeding Shorthorn as well as grading up were not successful.

5.3.2. Sudan

Osman & Russell (1974) studied data on local cattle and Bos taurus crosses at Ghurashi Farm in Northern Sudan. The foundation stock consisted of Butana females. The first Bos taurus bulls introduced were a Dairy Shorthorn (1925) and an American Holstein-Friesian bull (1927). After 1950 also Ayrshire, Guernsey and British-Friesian bulls were used. However, most cows were sired by crossbred bulls. The study covered a period of 35 years (1935–70) and used data on 198 native and 1066 crossbred cows. The records were analysed by least squares, eliminating effects of possible time trends. An extract of results is reported in Table 5.3.2.

TABLE 5.3.2.
PERFORMANCE OF DIFFERENT GRADES OF EUROPEAN-ZEBU CROSSBRED CATTLE AT GHURASHI FARM, SUDAN. Source: Osman & Russell (1974).

Age at first calving and calving interval in crosses tended to increase with increasing proportion of Bos taurus inheritance, but the native cattle had longer calving intervals than any of the crosses. However, number of services per conception did not differ significantly among genetic groups. Both lifetime milk yield and milk yield per annum (i.e. lifetime milk yield divided by years of productive life) increased with proportion of Bos taurus (except for a small group of 3/4). It was noticed that all components of stress (death rates, infertility etc.) increased with increasing proportions of exotic inheritance. A separate analysis of Friesian crosses showed the same tendencies.

5.3.3. Ethiopia

At Asela in the Arsi region (Central Highlands) of Ethiopia crossbreeding of Bos indicus and Bos taurus cattle commenced in 1968 (Kiwuwa et al. 1983). The Bos indicus component was the local Arsi cattle and various other local breeds (in the report the latter were collectively termed Zebu), while the Bos taurus stock was Jersey (discontinued in 1970) and Friesian. Feeding regimes were based on pasture with a minimum of concentrate supplementation according to milk yield. Traits studied were age at first calving, lactation milk yield and butterfat content, lactation length, calving interval, and cow body weight, along with a number of variables derived from two or more of these traits. Influence of possible time trends was removed by least squares analysis. A summary of results is given in Table 5.3.3.

TABLE 5.3.3.
PERFORMANCE OF LOCAL AND CROSSBRED CATTLE IN ARSI REGION, ETHIOPIA. Source: Kiwuwa et al. (1983).

The 5/8F 1/8J 1/4 A group calved at a significantly younger age than all the other genetic groups; differences among the others were small and insignificant. Calving intervals were shortest for Jersey × Arsi and Friesian × Arsi F₁ crosses, and increased with increasing proportion of Bos taurus (i.e. Friesiant inheritance above the 50% level. The first generation of crossbreds (F₁) produced more than twice as much milk per lactation as the local breeds, and this increase continued when the proportion of Bos taurus was increased to 75%, while fat percentage showed the opposite trend. A measurement of dairy productivity computed as annual fat-corrected milk yield per unit metabolic weight of cow did not differ significantly among the various crosses, but all crossbreds were widely superior to the local breeds. Comparing the Jersey x Arsi and Friesian × Arsi F₁ crosses, Jersey crosses produced 12% less milk per lactation, but this was outweighed by a higher fat content. The shorter calving interval and the lower body weight of the Jersey crosses gave them a 10% superiority in dairy productivity; however, this difference was not statistical ly significant. Performance levels of crossbreds on smallholder farms were similar to those at the station, and the ranking was also similar.

5.3.4. Kenya.

Kenya is the only African country with major resources of a recognised dairy breed of Bos indicus. Sahiwal cattle from India and Pakistan were introduced during the colonial era, and Kenyan Sahiwals have served as an important source of breeding material for the whole continent (Trail & Gregory, 1981). In Kenya itself Sahiwals have been used both for upgrading of the local East African Zebu and for crossbreeding with Bos taurus breeds.

Meyn & Wilkins (1974) presented results based on data collected by the second author at two large, well-managed farms in Kenya. One of the farms was located in a high-potential area and had Jersey and Jersey × Sahiwal crosses, the other farm was in a semiarid area and had Friesian and Friesian × Sahiwal crosses. The type of cross was not specified (presumably F,). The Jersey × Sahiwal crosses produced more milk than Jersey, while the Friesian × Sahiwal crosses were out-yielded by the pure Friesian. On both farms the group with the higher milk yield had also slightly longer calving intervals (Table 5.3.4.1). Friesians had more abortions (5.6 vs. 2.7%) and higher calf mortality to weaning (8.5 vs. 3.5%) than the Friesian × Sahiwal crosses.

TABLE 5.3.4.1.
DAIRY PERFORMANCE OF SAHIWAL CROSSES WITH JERSEY AND FRIESIAN AS COMPARED WITH THE EXOTIC BREEDS AT TWO FARMS IN KENYA. Source: Meyn and Wilkins (1974).

Kimenye & Russell (1975) examined data for high grade Ayrshire and Ayrshire × Sahiwal crosses at Kilifi Plantations, situated at the coast of Kenya near Mombasa. The grade Ayrshire herd was established by continuous upgrading of East African Zebu with Ayrshire bulls. At one stage the Ayrshire grades were mated to Sahiwal bulls, and the female progenies from these matings were mated to Ayrshire bulls. This two-breed rotational crossbreeding system was initiated as early as 1939. The traits studied were lactation milk yield (305 days), lactation length, calving interval, and age at calving. Effects of season of calving and possible tine trends were eliminated by applying least squares analysis. Records for each of lactations 1 to 8 were analysed separately, and results were pooled over lactations (altogether 2133 lactation records). The analysis of variance showed that effects of season and breed × season interaction were negligible, while effects of year were important for most traits. Average age at first calving, lactation milk yield, and calving interval (all lactations combined) for each genetic group are presented in Table 5.3.4.2.

TABLE 5.3.4.2.
PERFORMANCE OF HIGH GRADE AYRSHIRES, SAHIWAL X AYRSHIRE CROSSBREDS, AND THEIR BACKCROSSES TO AYRSHIRE AT KILIFI PLANTATIONS, KENYA. Source: Kimenye & Russell (1975).

Age at first calving was similar for the three groups. The 3/4 Ayrshire group had the highest milk yield, and both crossbred groups had shorter calving intervals than the high grade Ayrshires, but the differences were not dramatic. In milk yield per day of calving interval the high grade Ayrshires were the poorest. It was concluded that “a fair proportion of Bos indicus genes is desirable in this environment”.

Trail & Gregory (1981) analysed more recent data from the same herd. At this stage (1972–78) the proportions of Sahiwal and Ayrshire inheritance were stabilised at approximately 2/3 and 1/3, or vice versa. A large number of traits were studied, including age at first calving, lactation yield, and calving interval. Least squares means for the two genetic groups are given in Table 5.3.4.3.

TABLE 5.3.4.3.
PERFORMANCE OF AYRSHIRE × SAHIWAL CROSSBREDS AT KILIFI PLANTATIONS, KENYA. Source: Trail & Gregory (1981).

The 2/3 Ayrshire - 1/3 Sahiwal group was slightly younger at first calving and had slightly higher lactation yields. As to calving interval, the overall difference between genetic groups was small, but an important interaction between genetic groups and years was observed (Sahiwal-sired cows had shorter calving intervals in dry years). In general the results are in good agreement with those presented by Kimenye & Russell (1975) from the same herd (see above).

In the same report Trail & Gregory (1981) presented results from Ayrshire × Sahiwal crossbreeding at two ranches, Deloraine Estates and Cedarvale Farms, both in the Rift Valley. In both herds a combination of hand milking and calf suckling was practiced, and the groups assumed to have higher production potential were given some kind of preferential treatment, in the Deloraine herd the genetic groups compared were Ayrshire, Sahiwal (7/8 Sahiwal) and their reciprocal crosses. Estimated total milk production and calving interval did not differ significantly among groups, while age at first calving increased by increasing proportion of Sahiwal inheritance. A productivity index computed by combining live weight of 1-year-old calf and liveweight equivalent of milk produced was highest for the crosses and lowest for the Sahiwals.

At Cedarvale reciprocal F₁ crosses between Ayrshire and Sahiwal, and both backcrosses (i.e. 3/4 A - 1/4 S and 1/4 A - 3/4 S) were represented along with purebred Sahiwal. In addition there were a few Sahiwal × Friesian crosses. All crossbred groups were younger at first calving and had higher milk yields than the Sahiwal. Calves out of Sahiwal dams also had low survival rates. Among the crossbreds differences in age at first calving, milk yield and calf survival were small. Based on the difference between the mean of the reciprocal F₁ crosses and the mean of the two backcrosses heterosis was estimated to reduce calving interval by 16 days and increase lactation yield by 230 kg.

Kimenye (1978) analysed limited sets of data on Sahiwal, Ayrshire and their crossbreds at Machakos and Ngong Veterinary Farms, both near Nairobi, Kenya. Only age at first calving and first lactation length and milk yield were studied, and least squares procedures were applied. Results are presented in Table 5.3.4.4.

In both farms age at first calving was highest in Sahiwal, but the ranking of the other groups was inconsistent. Milk yield increased rather regularly (considering the small numbers) with increasing proportion of Ayrshire. The halfbreds were only slightly above midparent means. Lactation length showed a similar pattern to yield.

TABLE 5.3.4.4.
DAIRY PERFORMANCE OF SAHIWAL, AYRSHIRE, AND THEIR CROSSES AT MACHAKOS AND NGONG VETERINARY FARMS, KENYA. Source: Kimenye (1978).

(1) For the two reciprocal crosses the first breed refers to the sire and the second breed to the dam.

5.3.5. Tanzania

Breeding work at the Livestock Production Research Institute at Mpwapwa in Central Tanzania, dating back to early 1930's, resulted in the development of a mixed Indo-African zebu type cattle with a small proportion of Bos taurus inheritance. The composition of the herd in 1958 was reported to be (MacFarlane, 1970):

From 1968 to 1971 some Mpwapwa females were mated to Friesian, Ayrshire and Jersey bulls to produce a crossline, and the crossline females were backcrossed to Mpwapwa bulls. Mkonyi (1982) compared the performance of Mpwapwa , crossline and backcross (3/4 Mpwapwa) cows for dairy traits, but did not distinguish between various Bos taurus sire (or grandsire) breeds. Results are extracted in Table 5.3.5.1.

TABLE 5.3.5.1.
PERFORMANCE OF MPWAPWA CATTLE AND BOS TAURUS X MPWAPWA CROSSBREDS AT LIVESTOCK PRODUCTION RESEARCH INSTITUTE, MPWAPWA, TANZANIA. Source: Mkonyi (1982).

Age at first calving and calving interval decreased significantly with increasing proportion of Bos taurus inheritance. Milk yields were highest in the crossline and lowest in the Mpwapwa, and the difference increased as cows matured. The backcrosses were intermediate, but closer to Mpwapwa. Differences among groups in milk composition were nonsignificant and inconsistent from one lactation to another.

Mahadevan & Hutchison (1964) compared East African Zebu ( Boran and Jiddu types) and its crosses with various Bos taurus breeds (Guernsey, Jersey, Friesian, and Ayrshire) at the Livestock Research Centre at Tanga in the coastal region of Tanzania. Least squares techniques were used to eliminate the influence of time trends. Results are given in Table 5.3.5.2.

TABLE 5.3.5.2.
PERFORMANCE OF CROSSES OF BOS TAURUS AND BOS INDICUS CATTLE FOR MILK PRODUCTION IN THE COASTAL REGION OF TANZANIA. Source: Mahadevan & Hutchison (1964).

Crosses ranging from 1/4 to 3/4 Bos taurus inheritance produced nearly twice as much milk as the East African Zebu. Among the crossbreds the 1/2 Bos taurus group had slightly higher milk yields than the two others, and Friesian crosses outyielded Channel Island (Guernsey and Jersey) crosses. Length of calving interval increased with the proportion of Bos taurus inheritance.

In a more recent crossbreeding project at the Tanga centre Sahiwal females were mated to Friesian, Ayrshire and Jersey bulls. Preliminary results as reported by Shekimweri (1982) are extracted in Table 5.3.5.3.

TABLE 5.3.5.3.
COMPARISON OF FRIESIAN, AYRSHIRE AND JERSEY CROSSES WITH SAHIWAL AT TANGA, TANZANIA. Source: Shekimweri, (1982).

No significant difference among sire breeds was found in age at first calving and calving interval. For milk yield, Friesian crosses were superior to the other crosses.

5.3.6. Nigeria.

In Nigeria (and most other countries in West Africa) the purpose of most crossbreeding projects has been to upgrade the local cattle (Bos indicus and Bos taurus) towards a European breed. One example is the crossbreeding which was started at Shika Research Station in Northern Nigeria in 1964, involving White Fulani (Bos indicus) and Friesian. Records collected up to 1978 were analysed by Buvanendran et al. (1981), applying least squares techniques to eliminate the effect of possible time trends. Results are sumarized in Table 5.3.6.1.

TABLE 5.3.6.1.
PERFORMANCE OF FRIESIAN × WHITE FULANI CROSSBREDS AT SHIKA RESEARCH STATION, NIGERIA. Source: Buvanendran et al. (1981).

Differences between genetic groups in age at first calving, calving interval and calf mortality were all statistically non-significant. The only pronounced difference was in milk yield, which increased significantly as the proportion of Friesian inheritance was raised from 1/2 to 7/8.

The same two breeds were used for crossbreeding also at the National Veterinary Research Institute, Vom (1280 m above sea level) and at Agege Dairy Farm ( near Lagos). Results from the former project were reported by Knudsen & Sohael (1970). Milk yields of various group were as follows.

The difference in milk yield between 3/4 Friesian produced by means of natural service and those resulting from imported semen of first class bulls was highly significant, while no such difference was observed between the corresponding F, groups. The large superiority of the imported Friesians over Friesians born in the herd is also worth noticing.

More recently Sohael (1984) reported updated results from the same herd, as set out in Table 5.3.6.2.

TABLE 5.3.6.2.
PERFORMANCE OF WHITE FULANI, FRIESIAN AND THEIR CROSSES AT NATIONAL VETERINARY RESEARCH INSTITUTE, VOM, NIGERIA. Source: Sohael (1984).

(1) imported 1962–65

(2) Imported 1974–75

Friesian and Friesian crosses were similar in age at first calving, both calving 15 to 18 months earlier than White Fulani. Milk yield and lactation length increased almost linearly with proportion of Friesian inheritance, while fat content changed in the opposite direction. There was no pronounced difference between groups in calving interval.

At Agege Dairy Farm average milk yields of White Fulani, F., and 3/4 and 7/8 Friesians were 877, 1329, 2814 and 2485 kg respectively (Laseinde, 1979, quoted by Ngere, 1979).

5.3.7. Ivory Coast.

A project for crossbreeding N'Dama cattle with Jersey at the Animal Husbandry Research Centre in Ivory Coast was described by Letenneur (1978). The experiment was designed to compare crosses with various proportions of inheritance from each of the two breeds. Calves of N'Dama cows suckled their dams while calves of crossbreds were separated from their dams at birth and bucket-fed up to weaning at four months of age. Results on dairy performance are given in Table 5.3.7.

Backcrosses to Jersey (3/4 J) produced about 15% more milk than F., but had slightly lower fat content. Calving intervals were similar for all crossbred groups, and nearly two months shorter than for pure N'Dama. Mortality was very high among the high grades.

TABLE 5.3.7.
DAIRY PERFORMANCE OF JERSEY × N'DAMA CROSSES IN IVORY COAST. Source: Letenneur (1978).

5.4. LATIN AMERICA

A review of work providing information on the performance of various groups of cattle and their crosses in Central and South America was presented by Vaccaro (1979). Most of the reports reviewed were on crosses of European dairy breeds with the native criollo, but some reports on Bos taurus × Bos indicus crossbreeding were also included. As pointed out by the reviewer the various sets of data, taken individually, may not permit exact comparisons, as numbers of animals were small, and the various genetic groups were not always contemporary and subjected to the same level of manageent. However, the review concludes that the performance of pure-European breeds has often been disastrous (retarded growth, high mortality, poor fertility). In general it appears that the optimum level of European inheritance will exceed 1/2 and be about 5/8 or 3/4. In the present study only a few selected publications mentioned by Vaccaro (1979) are considered, along with more recent reports.

5.4.1. Brazil

In an article on crossbreeding strategies for dairy cattle in Brazil Madalena (1981) reviewed work by Vencovsky et al (1970), Reis (1977), and others, as well as work by himself and his coworkers (Madalena et al., 1978; Freitas et al., 1980).

Vencovsky et al., (1970) compared milk yields of Guzerat, Holstein, and their crosses ranging from 1/8 to 7/8 Holstein inheritance. The yields increased continuously with increasing proportion of Holstein up to 5/8, which produced about 60% more than Guzerat. Above this level a slight decline occured. A similar decline was observed by Reis (1977) for levels of Bos taurus inheritance above 1/2 to 5/8.

Madalena et al. (1978) compared milk production of Holstein × Gir F, crossbreds, backcrosses to Holstein, and pure Holstein at Santa Monica Experimental Station near Rio de Janeiro. Records of 637 lactations were analysed by least squares techniques, accounting for effects of year and season of calving, parity, and genetic group. Reproductive traits of the same crosses were studied by Freitas et al. (1980). Results are summarized in Table 5.4.1.

Age at first calving was lower, milk yield higher, and calving interval shorter for F, crosses than for pure Holstein, the backcrosses with 3/4 Holstein inheritance being in general intermediate to the two other groups. As to calving interval, differences between groups were slight for intervals initiated in the dry season, but very large for intervals initiated in the rainy season. The crossbreds were found to have a higher persistency than Holstein (Madalena et al. 1979) .

TABLE 5.4.1.
PERFORMANCE OF HOLSTEIN × GIR CROSSBREDS AND PURE HOLSTEIN AT SANTA MONICA EXPERIMENTAL STATION, BRAZIL. Sources: Madalena et al.(1978), Freitas et al. (1980).

Madalena et al. (1982) presented preliminary results from a crossbreeding experiment in which six Holstein × Guzerat grades (ranging from 1/4 to 15/16 Holstein) were produced. At 16 to 28 months of age 168 heifers were distributed to cooperator farms, one heifer of each grade to each farm, while 91 heifers remained at the experiental station. Cooperator farms were classified into high or low levels of manageent. Age at first calving was lower for halfbreds (F,) than for any of the other groups. In high level farms maximum milk yield was observed in F, and the high grades (>3/4 H), while 15/16 Holsteins had very low yields in low level farms.

Teodoro et al. (1984) studied variation in age and weight at puberty, age at first conception, and number of services per conception in the heifers maintained at the experimental station. A model including additive breed differences and heterosis was fitted to the data. Heterosis effects were significant for age and weight at puberty and for age at first conception, while only the latter showed a significant additive breed difference (Holsteins slightly younger).

The Pitangueiras cattle of Brazil is a Bos indicus - Bos taurus composite, carrying about 3/8 Bos indicus (Guzerat) and 5/8 Bos taurus (Red Poll) inheritance. Lobo (1976) compared two generations of these cattle, the first produced by mating 3/4 Guzerat - 1/4 Red Poll females to Red Poll males, and the second by mating first generation animals inter se. From generation 1 to generation 2 age at first calving increased two months and milk yield decreased 13% while there was no pronounced change in lactation length and calving interval.

Lobo et al. (1984) reported average milk yield of cows of generations 1 to 5. The decline in milk yield from first to second generation was confirmed, while no further decline was observed in subsequent generations.

The least squares means were:

5.4.2. Bolivia.

In Bolivia and many other Latin American countries the traditional system of milk production is dairy ranching. Usually calves run with their dams on natural pasture during daylight hours but are separated in the night, and the cows are milked (with the calf present) in the morning.

Breinholt (1982) reported from a dairy ranching project on sixteen small-scale ranches in the lowlands of Bolivia (near Santa Cruz). The herds included criollo, zebu × criollo crosses and crosses with Bos taurus breeds (Friesian and Brown Swiss). Records on dairy performance of various genetic groups are entered in Table 5.4.2.

TABLE 5.4.2.
DAIRY PERFORMANCE OF VARIOUS GENETIC GROUPS ON SMALL-SCALE DAIRY RANCHES IN BOLIVIA. Source: Breinholt (1982).

Pure exotics produced significantly more milk than criollo and zebu × criollo crosses , while the exotic crosses were intermediate in milk yield. The calving rate was low in exotics and high grades.

5.4.3. Colombia

Rubio (1976) compared the performance of Costeno con Cuernos (a dairy criollo), Holstein, and their F₁ crosses at the National Agriculture Investigation Centre, Turipana. Results are presented in Table 5.4.3.

TABLE 5.4.3.
PERFORMANCE OF COSTENO CON CUERNOS, HOLSTEIN AND THER Fl CROSSES AT TURIPANA, COLOMBIA. Source: Rubio (1976), after Wilkins (1984).

Both Holstein and F, crosses produced about 2.5 times as much milk as the local cows, and were about six months younger at first calving. Pure Holsteins had long calving intervals.

5.4.4. Jamaica

In Jamaica a comprehensive crossbreeding program was initiated in 1910 at the Hope Farm near Kingston. The program, which included several Bos taurus dairy breeds as well as Sahiwal and cattle of mixed origin, led to the development of the Jamaica Hope breed. This composite breed has received about 80% of its inheritance from Jersey, 5% from Holstein-Friesian, and 15% from Sahiwal. Details of the breeding program and production characteristics have been reported by Wellington & Mahadevan (1975) and Wellington (1979).

In three large commercial herds average age at first calving in 1975/76 ranged from 31 to 34 months, milk yield from 2920 to 3233 kg, and calving interval from 12 to 15 months. Data comparing the productivity of Jamaica Hope with other relevant breeds or crosses appear to be scanty , but the breed has been claimed to be veil adapted to the local conditions and to be superior to e.g. Holstein-Friesian in overall productivity under these conditions. Breeding animals and semen have been exported to many countries throughout Latin America.

5.4.5. Cuba.

The cattle breeding policy in Cuba has been based mainly on pure Holstein-Friesian and Holstein-Friesian crosses (Planas et al. 1979). Prada (1979) reported performance results of grades ranging from to 7/8 Holstein-Friesian inheritance. Some of the results are presented in Table 5.4.5.

TABLE 5.4.5.
PERFORMANCE OF HOLSTEIN AND H0LSTE1N × ZEBU CROSSES IN CUBA. Source: Prada (1979) .

The change in age at first calving with increasing proportion of Holstein-Friesian was irregular. pure Holstein produced more milk than any of the crosses, but had a lower fat content. Intermediate crosses (H and 5/8 H) had the shortest calving interval.

5.4.6. Costa Rica

Alba & Kennedy (1985) analysed records collected in a crossbreeding project at Turrialba, Costa Rica, from 1954 to 1981. The breeds crossed were Jersey and Milking Criollo. The records were analysed according to a model that included effects of year of calving, parity, and genetic group. Two data sets were created, one which was intended to include data from all calvings (minimum restriction) and another, set including only lactations with normal let-down without the presence of the calf. The results are summarized in Table 5.4.6.

TABLE 5.4.6.
MILK PRODUCTION OF CRIOLLO, JERSEY AND THEIR CROSSES AT THE INTER-AMERICAN INSTITUTE OF AGRICULTURAL SCIENCES, TURRIALBA, COSTA RICA. Source: Alba & Kennedy (1985).

The two F₁ groups had the highest milk yield in both data sets. In fat content there was no significant difference between the various genetic groups. Criollo and 1/4 Jersey had shorter lactations than the other groups, particularly when the analysis was not restricted to lactations with normal let-down. Heterosis was estimated at 21–26 percent for milk yield and 9–15 percent for lactation length.

5.4.7. El Salvador.

Reaves et al. (1985) analysed data collected in 19 herds from 1967 to 1972. The herds were participating in an upgrading program in which semen from Holstein arc Brown Swiss bulls was used. Foundation stock was composed of Brahman (Zebu), Criollo and native cattle of mixed, non-descript origin. The data were analysed by least squares analysis of variance according to models including effects of herd, year, age and genetic groups. Holstein and Brown Swiss data were analysed separately. Results are given in Table 5.4.7.

TABLE 5.4.7.
MILK YIELD AND LACTATION LENGTH OF HOLSTEIN AND BROWN SWISS CROSSES IN EL SALVADOR. Source: Reaves et. al. (1985).

In both groups milk yield increased with increasing proportion of Bos taurus inheritance, while the effect on lactation length was negligible. Brown Swiss crosses produced consistently more milk than Holstein crosses. Average milk yield of Brahman and Criollo was 1974 and 2083 kg, respectively.

5.4.8. Mexico

Berenguer (1984) reported results obtained for Indobrazil (a Bos indicus synthetic breed), Criollo and Holstein × Indobrazil at the Veterinary Faculty's Tropical Research Station. The cows were kept on a rotational grazing system with supplementation of sugarcane (2 kg), urea and minerals.

Indobrazil and Criollo were similar in age at puberty, milk yield and lactation length, but the former had longer calving intervals. The Holstein × Indobrazil crosses were superior to the other groups in all traits studied, and produced nearly three times as much milk per day of calving interval.