The Assessment On Production Performance And Study On Polymorphisms Of The Growth Hormone Receptor Gene And Association Analysis With Production Performance In Yellow Cattle Of Dual Purpose Strain In Northern Anhui

In this study, the production performance of 69 cows from nucleus herd of Yellow Cattle of Dual Purpose Strain in Northern Anhui were measured. The weight and size at birth, 6 months, 12 months and 18 months of age were measured; the carcass traits and meat quality traits of young bulls which were fattening were measured; milk production and milk quality of cow were measured. Based on above , production traits of new bleed were assessed. Blood samples of 69 cows from nucleus herd were collected and DNA of the blood were extracted by method of Phenol-chloroform; the genetic variation in 5 'end of GHR gene of new bleed was studied by PCR-RFLP and theoretical basis of molecular breeding in dual purpose variety was provide by this study.First, the weight and size of 69 cows from nucleus herd, 96 local yellow cattle and 47 Simmental hybrid cattle were measured and analysed. The results showed that: the average weight at birth of bulls and cows of new bleed were 34.25kg and 30.51kg, the weight of 6-month-old were 225.3kg and 216.6kg, the weight of 12-month-old were 295.3kg and 265.3kg, the weight of 18-month-old were 493.4kg and 435.4kg, have a very significant increase (p<0.01) relativing Simmental hybrid cattle and local yellow cattle; other aspects of size also had significantly or very significantly improvement (p<0.01,0.05>p>0.01). 5 bulls of 18-month-old from new bleed 5 bulls of local yellow cattle were slaughtered, and carcass traits and meat quality traits were measured and analyzed, results showed that: dressing percentage and net meat percentage of new bleed were 61.3% and 52.1%, had a very significant increase (p<0.01) relativing the local cattle ; brightness (L *) , tenderness and water holding capacity of loin , eye muscle , gluteal muscle of new bleed had significant or very significant improvement(p<0.01,0.05>p>0.01). Milk production performance of new bleed and Simmental hybrid cattle were measured and analysed, results showed that: production of 305 days of new bleed amounted to 4330.41kg , milk fat percentage was 4.40 %, milk protein ratio of 3.87%; milk yield had a very significant increase (p<0.01) than Simmental hybrid cattle with increase of 25.18%, fat percentage and milk protein ratio of new bleed had a significant increase (0.05>p>0.01) than the Simmental cross cattle with increase of 10.26% and 11.96% .5 'end of growth hormone receptor (bGHR) gene of new bleed was analysed by PCR-RFLP with two restriction enzymes (Cfr13 I and Sat I), and association between polymorphism and size of the new bleed were analysed. The results showed that: at Cfr13 I restriction site, frequency of C allele was 0.804, T allele was 0.196; C allele was the dominant allele;χ2 test showed that this site was according with the Hardy-Weinberg equilibrium (p>0.05); Polymorphism Information Content was 0.236, which slightly polymorphic (PIC<0.25) and had less genetic; at Sat I restriction site, frequency of C allele was 0.841, T allele was 0.159; C allele was the dominant allele;χ2 test showed that this site was according with the Hardy-Weinberg equilibrium (p>0.05); Polymorphism Information Content was 0.229, which slightly polymorphic (PIC<0.25) and had less genetic; at Cfr13 I restriction site, the weight and chest circumference of birth, 6-month-old, 12-month-old, 18-month-old of CC and CT genotypes had significant difference (0.05>p> 0.01) than the TT genotype.