Preliminary results on crossbreeding Jerseys with Fleckvieh sires

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8 CROSSBREEDING Little information is available in South Africa on the effect of crossbreeding dairy cows. Most crossbreeding trials in other countries have been conducted with Holsteins while Jerseys have received little attention being a breed with relatively small numbers. The objective of this study is to compare the total income (milk and beef production) of Jersey and Fleckvieh x Jersey cows in an intensive feeding system. Materials and Methods The study is being conducted at the Elsenburg Research Station of the Western Cape Department of Agriculture. Elsenburg is situated approximately 50 km east of Cape Town at an altitude of 177m, longitude 18° 50’ and latitude 33° 51’ and is in the winter rainfall region of South Africa. The area is characterised by cool wet winters and long dry summers. The Jersey herd at Elsenburg was divided into two groups according to age and estimated breeding value for milk yield. Groups were allocated randomly to two treatments, i.e. breeding with (i) Jersey or (ii) Fleckvieh sires. In the following breeding period, treatments will be switched and female animals All feed intake is measured at the research facilities Table 1: The number and growth performance of all bull and heifer calves born from Fleckvieh and Jersey sires in the Elsenburg Jersey herd Sire used Parameters Jersey Fleckvieh Number of cows calving down 31 32 Live weight of dams before calving (kg) 452 457 Number of calves born alive 28 26 Birth weight of calves (kg) 26.4 31.9 Number of calves at last weighing 24 26 Age at last weighing (days) 190 154 Live weight at last weighing (kg) 124.7 125.4 Average daiy gain (kg) 0.435 0.557 Calculated live weight at 6 m of age (kg) 106.5 133.5 will be inseminated with sires from the other breed. All pure- and crossbred bull and heifers calves born from these matings in the herd are being reared in the same way. Heifers are reared to calve down at approximately 24 months of age while bull calves are reared to be marketed at either six or 24 months of age. The bull calves marketed at six months of age are being reared intensively for veal production. Bull calves reared for beef are castrated with a Burdizzo at about three months of age and reared on pasture from six months of age. They receive a concentrate supplementation of 2 kg per animal per day up to 12 months of age. Heifers receive a calf starter meal containing 18 % CP ad libitum from 7 days of age until 2 months of age. A growth meal containing 15 % CP is then provided ad libitum until 5 months of age. At this age, heifers are put on kikuyu pasture. The pasture is supplemented with a growth meal containing 15 % CP starting from 1 kg per calf per day to a maximum of 3 kg per calf per day until 15 months of age. Heifers are inseminated from 13 months of age provided they are heavier than 200 kg. Bull and heifer calves are dehorned at two months of age. Ease of calving resulting from Fleckvieh and Jersey sires is noted for all cows. After calving, first lactation Jersey and Fleckvieh x Jersey cows will be put in zero-grazing open camps. They will receive a total mixed ration formulated according to the NRC (2001) feeding requirements for Jersey cows. The TMR’s will be provided to the cows in feed troughs on a daily basis to ensure an ad libitum feed intake. Jersey and crossbred cows will be kept in separate open camps for daily feed intake estimation once a week. The milk yield and milk composition of all pure- and crossbred cows will be recorded according to standard milk recording procedures. Cows will be weighed before and after calving and thereafter every month until the end of the lactation period. Body condition score of each cow will also be recorded at each weighing. Cows will be inseminated from 60 days of age and the reproductive performance of each cow recorded. Hormonal treatment to get cows pregnant will be applied when cows that are 150 days in milk are not confirmed pregnant. The total milk income for both pure- and crossbred cows will be determined using current milk prices. Results and discussion This project is still at a very early stage. The insemination of Jersey cows and heifers at Elsenburg started in October 2005 and the first calves were born in July 2006. Although it would normally be considered a risk to inseminate FLECKVIEHWorld 2008
Jersey heifers with Fleckvieh sires, because of the possibility of distokia from larger than normal birth weights of calves, heifers and first lactation cows were also inseminated with Fleckvieh semen because of a small number of experimental animals in the herd. From the first round of inseminations, 63 Jersey cows had calved down resulting in 28 purebred Jersey calves and 26 Fleckvieh x Jersey calves (Table 1). The overall birth weights of Fleckvieh x Jersey calves were heavier than that of Jersey calves, i.e. 31.9 vs 26.4 kg. At the last weighing date (August 2007), Jersey calves were older (6.2 vs 5.1 months) explaining the heavier liveweight of Jerseys in comparison to Fleckvieh x Jersey calves. This is related to the chronological date of inseminations of cows. Considering each calf’s average daily gain and birth weight, the calculated live weight of Fleckvieh x Jersey calves at 6 months of age was 25 % higher than that of purebred Jersey calves. It seems that under similar feeding conditions, Fleckvieh x Jersey heifer calves tend to grow at a growth rate almost similar to that of Jersey bull calves. The feeding level of diets provided to crossbred heifers should probably be lower than for purebred heifers to prevent excess fat deposition in the udder of heifers as that could have a negative effect on the milk yield of cows after first calving. Table 2: FLECKVIEHWorld 2008 The number of calves born according to lactation number and gender since the start of the experiment is presented in Table 2. Although information is available on a small number of calves, it seems that birth weight increases with lactation number and gender. Three and five calves sired by Jersey and Fleckvieh bulls died during birth. These were mostly bull calves, i.e two Jerseys and four crossbreds. These were larger than normal bull calves, i.e. in excess of 45 kg. The proportion of dead calves was similar for first parity in comparison to older cows. The number of calves surviving after birth was similar for both sire breeds. While Jersey cows are known for their ability for easy calving, close attention of cows at calving should always be a high priority. The birth weights of heifer and bull calves in relation to dam live weights were 5.6 and 6.4 % for Jerseys and 6.9 and 7.1 % for Fleckvieh x Jersey crossbreds indicating the effect of gender and breed. Conclusion This project is still at a very early stage and <strong>results</strong> obtained should be interpreted with care. The main emphasis of the project is based on the milk yield and reproductive performance of crossbred cows in comparison to purebred Jerseys. Those <strong>results</strong> are still a long way off. The number and birth weights of calves and dam live weights before calving sired by Fleckvieh and Jersey bulls Parity of Jersey Fleckvieh Parameters dams Heifers Bulls Heifers Bulls Number of calves born 1 4 2 4 4 2 6 4 4 1 3+ 7 5 5 9 Birth weight (kg) 1 24.0 25.9 27.4 30.8 2 24.1 26.0 30.4 34.0 3+ 27.8 29.8 34.6 33.6 Dam live weight (kg) 1 425 367 408 399 2 477 446 458 341 3+ 469 460 490 510 CROSSBREEDING 9 Standardized conditions during the milk-feeding period Hippo-twins out of a Jersey cow. The white spots on their heads are typical for F1 Fleckvieh x Jersey (50 % Fleckvieh)
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Preliminary results on crossbreeding Jerseys with Fleckvieh sires

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