The present study was undertaken with six numbers of German Shepherd dogs from different locations of Belgachia, Kolkata, West Bengal. Semen samples were collected biweekly in the morning (8:00 hr) by massage method aseptically from each dog for six occasions. A total of 36 ejaculates were collected. After collection, all semen samples were pooled, and all the macroscopic characters and physicomorphological seminal characteristics were evaluated. The volume of semen, pH, sperm concentration, individual motility, live percentage of spermatozoa, positive for hypo-osmotic swelling test( HOST) and total sperm abnormality percentage were 5.516 ± 0166 cu mm., 6.383 ± 0.031, 274.333 ± 2.667 x10 6 /mL, 76.333 ± 2.728%, 84.166 ± 1.990, 80.166 ± 2.522 and 14.83 ± 2.386, respectively. In the study all the dogs were found fertile.
The effects of 18 buffalo sires, used in 2 years of a progeny-testing programme, on the subsequent lactation performances of their mates, were investigated from a study of 685 lactation records. The traits studied were: milk production, lactation length, length of post partum anoestrus, number of services per conception and length of service period (calving to conception). Parity of calving and sire had a significant effect on 305-day milk yield and lactation length of the mates. Between the 2 years, the sires did not differ for any of the traits of their mates. Although the breeding value of the sires, high or low, did not differ significantly, the sires with high breeding value tended to depress the milk production in the subsequent lactation of their mates and vice versa (r= -005). The birth weight of the calves significantly affected milk production. It was concluded that all methods of sire evaluation are likely to be biased by the effect of sires.
SUMMARYThe genetic parameters of lifetime production traits and their relationship with milk yield in first, second and third lactations were estimated from information on 753 Tharparkar cows. The heritability estimates for milk yield in first, second and third lactations were 0·22 ± 0·10, 0·33 ± 0·14 and 0·49 ± 0·17 and for number of lactations completed, lifetime milk production, number of days in milk and herd life 0·58 ± 0·23, 0·51 ± 0·22, 0·54 ± 0·22 and 0·34 ± 0·20 respectively. The genetic and phenotypic correlations among the four lifetime production traits were in the range of 0·83–1·0 and 0·84–0·85 respectively. The phenotypic correlations of milk yield in first, second and third lactations with lifetime production traits were significant and ranged between 0·15 and 0·56. The corresponding genetic correlations ranged between 0·26 and 0·83. For the first three lactations, the genetic correlations of lifetime traits with the third lactation were high and that between lifetime milk yield and yield in third lactation the highest (0·83 ± 0·17). The direct and correlated responses from single trait selection were also estimated.
The study was based on 1156 lactation records of 545 Murrah buffaloes. Initial milk yield, peak yield, ascending phase milk yield and days to attain peak daily production, the means of which were 26·7 kg, 10·3 kg, 407 kg and 58·9 days respectively, were all affected by period, season and parity of calving. Heifers recorded the least initial milk yield and peak yield and took the longest time to reach peak production. Peak yield was the most important single factor (R2 = 0·41) in causing variation in 43-week milk yield. The heritability estimates for initial, peak and ascending phase milk yields and days to attain peak yield were 0·35, 0·51, 0·27 and 0·13 respectively, whilst that for 43-week milk yield was 0·18. Peak yield had the highest phenotypic (rP = 0·64) and genetic correlations (ra = 0·68 ± 0·19) with the 43-week milk yield. Other genetic correlations with the 43-week milk yield were low and non-significant. The results indicated that indirect selection for peak yield would be more effective than direct selection for improving the 43-week milk yield in buffaloes.
The present study was conducted to evaluate the effect of dry matter restriction on morphometry (live body weight and body condition score) and blood biochemistry (glucose, blood urea nitrogen, creatinine and total protein) in unproductive cattle. Nine non-descript, crossbred cows (BCS over 4) were randomly distributed in 3 treatments (T 0 , T 1 and T 2 ). T 0 : the control group was fed with dry matter (DM) @ 2.5% of the body weight. T 1 and T 2 were fed with the restricted DM i.e., @ 2% and 1.5% of the body weight, respectively up to 21 days. After 21 days of feed restriction all the cows were fed normal diets i.e., 2.5% of the body weight for next 21 days. Declining rate in body weight were observed (P<0.05) in T 1 and T 2 during the restriction period as well as in re-alimentation. Body condition score was not significantly (P>0.05) affected in restriction period. A declining trend was observed in blood glucose and urea nitrogen concentrations during feed restriction but an increasing trend was also observed during re-alimentation. By this study we can conclude that upto 60% reduction in feed intake will not exert any harmful effect on morphology and physiology of cattle during feed scarcity.
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