Study On Growth Performance And Blood Physiological Characteristics Of Hu Sheep And Dorper-Hu Hybrid F1 Sheep

Hu sheep is an excellent local sheep breed,which has the advantages of perennial oestrus,high fertility,and good maternity.Dorper sheep is an excellent meat sheep breed imported from abroad.In this study,Hebei Qianmaoyuan Animal Husbandry Co.,Ltd.measured and analyzed the survival status,growth performance indicators and blood physiological indicators from different birth types of the first to the weaning period.Campared the twins lambs Dorper × Hu F1 and Hu sheep’s survival status,growth performance index from birth to weaning and blood physiological index during weaning.Growth performance indexes mainly include birth weight,15-day-old weight,1-month-old weight,weaning weight and the body size index such as body length,body height,chest girth at 1-month-old and weaning.At the same time,the cumulative growth,absolute growth and relative growth of weight were calculated for Hu sheep of different birth type and different sex.Blood physiological indexes mainly include WBC,RBC and HGB,etc.The results of this study are intended to provide a more scientific theoretical basis for the reproduction and cross breeding of the local Hu sheep.The specific results are as follows:1.Survival status: Hu sheep of different birth types(single lamb,twins lambs,3lambs and 4 lambs)died in turn 0,2,3 and 5 from birth to weaning,the survival rate was 100%,95.0%,90.0 % and 79.2% successively,indicating that the greater the number of lambs,the lower the survival rate.Dorper-Hu hybrid F1 sheep from the second-parity had no deaths from birth to weaning,indicating that Dorper-Hu hybrid F1 sheep had strong disease resistance and better reflected the heterosis.2.Changes of growth performance Hu sheep with different birth types from birth to weaning: the cumulative growth of weight showed that as the number of lambs increases,the weight of ram and ewe lambs decreased from birth to weaning at all time points.In absolute growth,with the increase of age,the growth rate of twinslambs,3 lambs and 4 lambs were gradually accelerated.By the time of weaning,the growth rate of twins lambs and 3 lambs had exceeded that of single lamb.In relative growth,from 1 month old to weaning,the growth intensity of 4 birth types gradually increased,especially 3 lambs and 4 lambs,which had exceeded the growth intensity of single lamb and double lamb.In addition,with the increase in the number of lambs,the body size indexes of ram and ewe lambs at 1 month old and at weaning all showed a decreasing trend.In most indexes,the difference between single lamb and twins lambs were not significant(P>0.05),and the difference between 3 lambs and 4 lambs were also not significant(P>0.05).The weights of ram and ewe lamb at 1 month old and weaning had a very significant positive correlation with most body size indexes(P<0.01),and had a significant positive correlation with a few indexes(P<0.05).The correlation coefficients between chest girth and 1-month-old weight and weaning weight were the largest,indicating that the chest girth of ram and ewe lamb had the greatest influence on weight at 1 month old and weaning.3.Comparison of growth performance between Hu sheep and Dorper-Hu hybrid F1 sheep: the cumulative growth of weight showed that Dorper-Hu hybrid F1 ram and ewe lamb had higher weight than Hu sheep at all time points,except for the birth weight.In absolute growth,from the first birth to 15 days old,Dorper-Hu hybrid F1 ram and ewe lambs were significantly higher than Hu sheep(P<0.01).From the15 days old to 1 month old and from1 month old to weaning,the absolute growth of Dorper-Hu hybrid F1 ram and ewe lamb were slightly lower than those of Hu sheep,but the difference were not significant(P>0.05).In the relative growth,from the first birth to 15 days old,Dorper-Hu hybrid F1 ram lamb were significantly higher than those of Hu sheep(P<0.01).In the ewe lamb,Dorper-Hu hybrid F1 were significantly higher than those of Hu sheep(P<0.05),From the15 days old to 1 month old and from1 month old to weaning,the relative growth of Dorper-Hu hybrid F1 ram and ewe lamb were slightly lower than those of Hu sheep,but the difference were not significant(P>0.05).In addition,most of the body size indexes of Dorper-Hu hybrid F1 ram and ewe lamb were higher than those of Hu sheep.4.Blood physiological characteristics of Hu sheep and Dorper-Hu hybrid F1sheep: most of the blood physiological indexes of Hu sheep of different birth types and Dorper-Hu hybrid sheep were within the standard reference value.In summary,as the number of lambs increases,the survival rate of Hu sheep gradually decrease.From birth to weaning,according to the measurement results of weight and body size indexes of different birth types,combined with economic benefits,it may be best to produce twins lambs in production practice.If the feeding and management are excellent,it is possible to produce 3 lambs.In addition,most of the growth performance indexes of Dorper-Hu hybrid F1 sheep at weaning are better than Hu sheep.Most of the blood physiological indexes of Hu sheep and Dorper-Hu hybrid sheep are within the standard reference value,indicating that Hu sheep has a good adaptability in Xingtai area of Hebei,and the heterosis with Blackhead Dorper sheep is obvious.