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20103
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Subject: Animal Genetics and Breeding × End date: 2010 × Start date: 2010 × Type: Thesis ×
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    ThesisItemOpen Access
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    ThesisItemOpen Access
    STUDIES ON GENETIC AND NON GENETIC VARIATIONS OF ANGORA RABBITS REARED IN KANGRA VALLEY OF HIMACHAL PRADESH
    (CSKHPKV, Palampur, 2010-07) SHARMA, Loopamudra; Katoch, Sanjeet
    ABSTRACT This study was conducted to evaluate the phenotypic profiles, genetic and non genetic effects on wool production and reproduction traits in 588 and 361 German Angora rabbits maintained at Angora Rabbit Breeding Farm, Kandwari, Kangra (Himachal Pradesh) from 2000 to 2009 for reproduction traits and from 2000 to 2007 for wool production traits. The data was analyzed by Harvey’s least squares method of fitting constants. The overall least squares means were 4.62 1.64 k, 30.39 0.58 d, 58.77 35.10, 169.77 30.38, 181.00 21.30, 184.73 23.49, 594.22 67.13, 591.82 193.67 and 1185.96 202.96 g respectively for litter size at birth, gestation period, wool yield at first, second, third, fourth clip, first year, second year and cumulative yield. Year and season of kindling significantly affected litter size at birth, wool yield at first, third, fourth clip and first year yield. Gestation period, wool yield at second clip, second year and cumulative yield were affected by year. Heritability estimates were 0.09, 0.29 0.030, 0, 0.312 0.021, 0.27 0.017, 0.412 0.028 and 0.116 0.013 respectively for wool yield at first, second, third, fourth clip, first year, second year and cumulative yield. Genetic correlations of wool yield at second clip with second year and cumulative yield, wool yield at fourth clip with second year and cumulative yield and first year with second year and cumulative yield were negative. Wool yield at first clip with cumulative yield, second with third clip and third with fourth clip, first year, second year and cumulative yield were zero. Wool yield at second clip with fourth clip had the highest genetic correlation (1.226 0.398). Phenotypic correlations of second clip with second year and third clip with second year yield were negative. Second year and cumulative yield had the highest significant phenotypic correlation (0.942). Winter appeared to be the most favorable season for breeding of Angora rabbits. Improvement can be achieved with proper selection and improved management practices. Pure breeding stock of Angora rabbits can be introduced to maintain superior genotypes and variability.
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    ThesisItemOpen Access
    GENETIC STUDIES ON INHERITANCE OF PART LACTATION MILK YIELDS IN RED SINDHI X JERSEY CROSSBRED COWS
    (CSKHPKV, Palampur, 2010-06) Verma, Nishant; Thakur, Y.P.
    ABSTRACT Records on 136 Red Sindhi x Jersey crossbred cows, maintained at Dairy Farm, Himachal Pradesh Krishi Vishva Vidyalaya, Palampur for 24 years (1981-2004) were analyzed for the effect of genetic group, season of calving, period of calving and parity of cow on cumulative part lactation milk yields. Heritabilities and genetic and phenotypic correlation coefficients were also estimated for these traits. The overall least square means estimated in this study for cumulative milk yields up to 30, 60,120,240 days were 267.46 ± 10.34kg, 548.82 ±21.57kg, 1061.27 ± 40.01kg and 1877.52 ± 59.98 kg respectively. The overall average for other traits viz. 305-days milk yield, total milk yield of lactation, lactation length, peak yield, calving interval, average milk yield per day of lactation length and average milk yield per day of calving interval were 2192.26±65.12kg, 2522.87±80.48kg, 375.11±4.02 days, 459.4±35.17days,12.76±0.36kg, 6.78±0.17kg and 5.61±0.16kg respectively. Cumulative part lactation milk yield traits were only affected by parity of cow. Genetic group, season of calving and period of calving were found to have no significant effect on these traits. The other traits viz. 305-days milk yield, total milk yield of lactation, lactation length, peak yield, calving interval, average milk yield per day of lactation length and average milk yield per day of calving interval, were not affected by genetic group, season of calving and period of calving and parity of cow except 305 days milk yield which was significantly affected by parity of cow. High heritability (0.54±0.19 of 30 days yield to 0.70±0.23 of 120 days yield) and high genetic and phenotypic correlations were observed among different part lactation milk yield traits. The correlation coefficients were moderate to high between part lactation milk yield traits and complete lactation milk yield traits. The high heritability of 60 days milk yield (0.68±0.22), 120 days milk yield (0.70±0.23) and moderate heritability of peak yield (0.324±0.15) and correlations of these traits with other complete lactation milk yield traits indicates that these traits can be utilized as reliable tools for early selection of dairy cows. Low heritabilities for calving interval and lactation length indicates that the length of these traits is much influenced by management and husbandry practices, which can be improved by better management practices.