Study On The Meat Performance Of New Breed Selection Population Of Gansu Modern Meat Sheep

Comparing ten-crossbred lambs of 5 months ages Poll Dorset×Mongolia sheep(DMF₃) and Poll Dorset×Small Tailed Han sheep(DHF₃) that were selected from Gansu modern meat sheep new breed selection population with a group of DHF₃ lamb under the same conditions for the control group.The comparison involveed fattening,slaughter and mutton lamb quality analytical test.the results as follows:1,60d short-term fattening experiment was carried out under the "grazing plus supplemental feeding" condition,the average daily gain of DMF₃ ram lamb was 304.50g/d,and ewe lamb was 292.83g/d,feed conversion ratio(FCR) was 2.98:1,and economic returns was 169 yuan per head.The result was higher than the lamb of DHF₃;absolute growth of ram and ewe lamb of DMF₃ were18.27 kg and 17.57 kg which were also higher than DHF₃.The average daily gain of ram and ewe lamb of DMF₃ and DHF₃ were all significantly higher than control group(P＜0.01).After calculations, fattening lambs have got significant economic benefits.2,Carcass of DM F₃ and DHF₃ were plump and have good quality,all the index were significantly higher than the comparison group(P＜0.01).The ram lamb of DMF₃ got the highest living weight,carcass weight and slaughter percentage,which were 35.50 kg,17.97 kg and 50.62%.And the eye muscle area was 11.10cm²,which was higher than the ewe lamb of DMF₃ and the crossed combination of DHF₃.Mutton production performance of DHF₃ was outweigh than the control group.The slaughter percentage of ram and ewe lamb were 3.77%and 3.42%higher than the comparison group.Area of longissimus doris and GR value were all significantly higher than the control group(P＜0.01).It proved that the economic traits of identical hybridized combination lamb were outstanding.3,Marbled strait of DMF₃ and DHF₃ crossbred combination lamb was all over 3 score.The mutton color was all between 3～4 scores.The cooked meat percentage (71.59%and 70.26%) and dehydration rate(10.81%and 10.40%) of ewe lamb were higher than the ram lamb,but shearing force ram lamb(4.41 kg and 4.36kg) was higher than the ewe lamb(3.98kg and 4.08kg).By analyzing crossed combination lamb nutritional ingredient of DMF₃ and DHF₃,it showed that:protein level was all above 20%,intermuscular fat content was 4%～5%,goodly succulency,muscle fiber diameter was 27.38μm and 26.89μm,have high meat tenderness,the category of fatty acid and mineral matter were abundant, stearic acid in fatty acid was as high as 47.12%and 48.23%which was the highest, octadecadienoic acid that was necessary for human body were 4.15%and 4.12%, Ca,Cu,Te,K and Na in mineral matter were plentiful,and have many kind of essential amino acids(EAA) at the same time.Two crossed combination lamb nutritional ingredient were closer,fatty acid content of DMF₃ was higher than DHF₃,but amino acid content of DHF₃ was higher than DMF₃.Lamb of DMF₃ and DHF₃ were all nutritional animal foodstuff which was the raw material for producing and processing high-quailty mutten,have great exploring worth.