pilers were three Independent experiments were carried on,ofwhlch nine breeds and two crossbreeds were selected as trial animals.The fat samples from three depots ofsubcutaneous,Intramuscular and kidney fat of*the sheep were t欢en for the study.Fat was exracteu by using the methods of Cold extraction,the 阶tyacldsprofile ofeach depotwas analyzed separately byGC,InåŠdition,the statlstlcalprocedures ofSAS were applied fordata analysis.Four aspects such asFat coè¡€ent,ä¼½yaclds profiles ofeach depot,cholesterol level In sheep meat and adipose cell were Investigated.Statistical analysis ingenetlc variation of fattyaclds profile among the sheep breeds,variation among depots,variation In dl地rentage of*thee sheep,IMFMF variation among the sheep breeds and growth stæ˜es,adipose cell developmentln different growth Stages ofsheep were studied.Therefore,a comprehensive understanding ofthegenetlc variation of Mtyaclds profiles,the relatlonbetween Mty acldsprofile and growth characters of*theters animals as well as the physiological and nutritional characters offatty acids ofnjmlnants,especially the sheepM were obtained. 多ignihcance genetic variation of fatty acids among s0eeP breeds Tilers were significant variations existing amoæ— the sheep breeds and genotypes.Fatty acids profile Is notonly Influenced by factors like sex,growtll St*gC nnd nUtfl*ms**d*nVlrO*i*nt bUt also***etlC nl***ï¼lp Of tile Sll**p 85 breeds. An identity of sheep breed in fatty acids profile is demonstrated for the sheep breeds. Linoleic acid (C 18:2) is the most variable fatty acid of sheep breed with significant breed identity. CLA, conjugated fatty acids being consisted of main part of the Linoleic acid shows significant effect to human health, and th~ special line of sheep with high content of CLA could be selected as it shows genetic variation among the breeds. IMP is also the most variable factors showing among the sheep breeds, the fast growth breed contains lower IMF in their muscles. Therefore, the combination of the crossbreeding has to be considered by commercial sheep industry or sheep farmers in order to maintain a optimum content of IMF and guarantee the better quality of sheep meat. Texel sheep is the most popular meat type sheep, which commonly used in the crossbreeding practice in commercial sheep industry. The Linoleic acid content in this breed is the highest among others involved in this experiment,. it is believed that the higher content of the Linoleic in Texel is due to its breeding history. The Lincoln and Leicester sheep were identified as the common sires in developing the Texel, which were rarely found in the breeding history of other breeds. Texel, Suffolk, Merino and Black face sheep were developed in a different breeding history with different sire and each of them should demonstrate identity of the its own genetic makeup, it also shows in its fatty acids profile. Therefore, this factor has to be considered in a crossbreeding or breeding practice so that the higher heterosis and better quality of meat can be achieved. The number of the adipose cell is determined genetically and deposit of the fat in sheep body is realized through enlarges of the adipose cell. Meat type sheep or meat genotype shows less number of adipose cells than that of other sheep breed. Mountain type s...
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