Study on growth traits at weaning and yearling stages of indigenous and F1 crossbred buffalo in Bangladesh

This study was planned to clarify the variation of body weight and average daily gain traits in both indigenous and F1 crossbreed (Local×Mediterranean) buffalo at weaning (sixth month) and yearling stages (twelfth month). Data were collected from 33 indigenous and 35 F1 crossbred buffalo progeny during the period of 2011 to 2014 with intensive management system at Research and Development farm of Lal Teer Livestock Limited in Bangladesh. The gathered data were analyzed using general linear model (GLM) and independent sample t test. The effect of parity, sex, season and breeding year on body weight and average daily gain were observed where significant values found in breeding period (p <0.01) of crossbred buffalo for body weight. It might be the reason of crossbreeding to indigenous buffalo cows using imported semen with better genetic merit. The parity (p <0.05), season (p <0.05) and breeding period (p <0.01) were also significant for average daily gain measurement which suggesting environmental adaptability beside additive genetic effects. Body weights were measured at weaning and yearling stages for both local (113 to 195 kg) and F1 crossbred (144 to 220 kg) buffalo progeny to screen the elite offspring for the Genetic Farm and Bull station. Similarly, average daily gain observed 469 to 457 g and 600 to 506 g at the previously mentioned two stages for both local and F1 buffalos, respectively. It was observed that studied traits were comparatively better in F1 buffalo progeny than indigenous. The comparison of average daily weight gains between indigenous and F1 buffalos at weaning and yearling periods showed significant differences for body weight (p <0.001) and average daily gain (p <0.05), respectively. It is concluded that genetic gain might be possible in local buffalo population by grading up process which could switch the traditional buffalo rearing to commercial level as well as meeting the nutritional demand of country people.Asian J. Med. Biol. Res. December 2017, 3(4): 499-503

Evaluation of overseas pig breeds using imported semen. 2. Prediction of carcass lean content

SummaryAn analysis of data from the complete dissection of one side from 285 animals from a breed comparison experiment was conducted to determine whether there were important biases in the prediction of percentage lean in the side based on dissection of the rumpback joint and, if so, whether the dissection of any of five other sample joints would have been better.For estimating lean content of the side, it was found that the lean content of any sample joint except the hand was a more precise predictor than standard carcass measurements alone, while including the latter in a prediction equation based on a single sample joint dissection improved precision further. For prediction based on lean in the sample joint alone, any one of the ribback, ham and rumpback was best. If other carcass measurements were included (in particular, C fat depth, eye-muscle area and trimming percentage were found to be useful), there was little to choose between the joints. For all joints there were differences between sire breeds (Large White, Canadian Yorkshire, U.S. Duroc, U.S. Yorkshire, Danish Landrace or Norwegian Landrace), sexes (hog or gilt) and feeding regimens (ad libitum or scale) in lean content of the side at constant lean content of the sample joint, but the regression slopes differed only when the rumpback or streak was used as a predictor, and then only between ad libitum and scale-fed pigs. It will therefore be important in any future such experiment fully to dissect a sample of each class (breed, feeding regimen and sex) to provide unbiased estimates of the differences in lean content. A sample of 30 from each class should allow the differences to be estimated adequately.

Evaluation of overseas pig breeds using imported semen 1. Growth and carcass performance

SummaryAlthough a given foreign breed may offer worthwhile genetic improvement, the cost of importing purebred stock makes its evaluation difficult. An experiment was performed in which the breeds compared were represented instead by semen from boars standing at national artificial insemination stations in their native countries. Contemporary groups of Large White × Norwegian Landrace females were inseminated, some with British Large White (LW) semen, and some with semen from Canadian Yorkshire (CY), Danish Landrace (DL), Norwegian Landrace (NL), or United States (American) Duroc (AD) or Yorkshire (AY). One pair (male castrate and gilt) from each litter was performance tested from 27 to 82 kg live weight fed ad libitum (AL), another pairwas tested over the same weight range but fed to a time-based scale (TS). The number of LW, CY, DL, AD, AY and NL sires used was 51, 12, 21, 7, 6 and 23 respectively; a total of 401 litterswas evaluated. The differences between the progeny of LW sires and those of CY, DL, AD, AY and NL were, respectively: in daily live-weight gain (g), AL, –30, 40, –80, –50, –40 (maximum s.E. 16) with no significant differences for TS; in food conversion ratio, AL,0·02, – 0·13, 0·03, –0·05, 0·00 and TS, 000, – 0·14, 0·05, –0·03, –0·06 (maximum S.E. 0·049 for both feeding regimens); in percentage of lean by weight in the rumpback joint, AL, –2·1, –1·9, –1·8, 2·3, –0·7 and TS, – 0·1, –0·9, –1·9, 3·0, – 1·4 (maximum s.E. 1·28 for both); in overall economic worth (pence per pig sired), AL, – 150, 50, – 170, 110, – 40 and TS, – 10, 100, – 200, 190, 30 (maximum s.E. 83 for both). The U.S. Yorkshire and Danish Landrace seem unlikely to be of use commercially in the U.K., while the most promising breeds, U.S. Duroc and Canadian Yorkshire, have not yet been evaluated with sufficient precision to reduce the risk involved in their use to an acceptable level.

Continuous progeny testing, use and selection of proven bulls in Israel

The breeding policy of the Israeli Holstein-type dairy cattle is reviewed. The bulls are progeny tested on their daughters’ first three lactations. The traits evaluated are the following: milk, fat, yield persistency, fertility, incidence of mastitis, and % cullings for three most important reasons. The test analysis takes into account the genetic level of daughters’ contemporaries and maternal grandsires. The paper describes a general outline of the selection decisions in AI bulls. Considerable amount of imported semen is used for breeding young bulls. Breeding goals are discussed against the estimated genetic parameters for and between the given traits.

Factors affecting calving difficulty and gestation length in cows mated to Chianina bulls and factors affecting the birth weight of their calves

SummaryImported semen from 10 Italian Chianina bulls was used to inseminate beef and dairy cattle throughout England and Southern Scotland. A total of 2134 records of calving performance were subjected to least squares analyses. Dystocia score was significantly affected by county of birth, parity of dam, sire, type of birth, birth weight (P < 0·001), season of birth and sex of calf (P < 0·01). There were no significant effects of breed or size of cow. Serious dystocia was encountered in 3% of calvings, with the incidence for individual sires ranging from 1·7% to 6·7%. Arithmetic mean gestation length was 284·2 days and it was significantly affected by county, sire (P < 0·05), sex of calf (P < 0·01), and type of birth (P < 0·001). Arithmetic mean birth weight of the calves was 41·2 kg and this was significantly affected by all main effects studied except season of birth and type of herd.