多產豬種之培育I.梅山豬與杜洛克豬雜交之產仔性狀

張伸彰 黃雅芬 李錦足 涂海南 陳芳男 李世昌 顏念慈 吳明哲 張秀鑾

行政院農業委員會畜產試驗所

母豬生產力為養豬產業經濟效率的一項重要因素，其主要組成性狀為分娩窩仔數和哺育期間仔豬育成率；然因其為遺傳變異率低之性狀，故很難經由選拔達到改進的目的。因此，應用具高繁殖力之中國本土豬種如梅山豬，進行雜交即為另一項選擇。本研究旨在評估多產梅山豬與杜洛克豬正反雜交之產仔性能，期供作選育適合台灣地區環境氣候高繁品系豬種之依據。應用梅山豬(M)公12頭、母53頭與杜洛克豬(D)公24頭、母42頭，於1997至1999年間進行正反雜交試驗，計分娩122窩（初產95胎與二產27胎）；其中M、D、MD（M母豬與配D公豬）與DM（D母豬與配M公豬）分別為18、14、50與40胎。評估性狀包括分娩總仔數（LS）與活仔數（LSA）、三週齡（LS3）與離乳窩仔數（LSW）、分娩活仔豬窩重（LTRWT）、仔豬出生（WT0）、三週齡（WT21）與離乳（WWT）平均體重、仔豬出生存活率（LSA/LS＝SURV1）與三週齡育成率（LSA/LS3＝SURV2）。結果發現：母豬產仔性能具顯著的品種效應，M母豬顯著地較D母豬有較大的LS、LSA、LS3與LSW（P<0.001）；然其仔豬之WT0、WT21與WWT，則顯著地較輕（P<0.001）。同時，正反雜交評估結果顯示LS3、LSW、SURV1、SURV2、LTRWT、WT0與WT21具顯著的雜交優勢，且其估值分別為30.1%、30.0%、17.5%、13.5%、22.4%、7.8%與10.5%（P<0.05）。

關鍵語：梅山豬、杜洛克豬、正反雜交、產仔性能。

DEVELOPMENT OF PROLIFIC LINE IN SWINE I. LITTERING
TRAITS OF MEISHAN CROSSING WITH DUROC

S. C. Chang, Y. F. Huang, F. C. Lee, H. N. Twu, F. N. Chen, S. C. Lee, N. T. Yen, M. C. Wu and H. L. Chang

Taiwan Livestock Research Institute, Council of Agriculture

Sow productivity is a major component of the production efficiency in pig industry. Litter size at birth and pre-weaning survival rate are the major component traits. However, these traits are difficult to improve through selection due to their low heritabilities. Crossbreeding could be another way to increase sow productivity by taking advantage of high prolificacy in some native Chinese breeds such as Meishan. The purpose of this study was to evaluate the littering performances of Meishan(M), Duroc(D) and reciprocal crosses(MD and DM defined as M sows sired by D boars and D sows sired by M boars, respectively) for the reference of the outstanding reproductive breeds selection in Taiwan. A total of 36 boars(including 12 M and 24 D breeds, respectively) and 95 sows(including 53 M and 42 D breeds, respectively) were used to produce 122 litters(95 and 27 litters produced at first and second parities, respectively) during 1997 and 1999. The data included 18, 14, 50 and 40 litters of M, D, MD and DM, respectively. Traits evaluated were litter size at birth(LS), born alive(LSA), at three weeks of age(LS3) and at weaned (LSW), litter weight born alive(LTRWT), average piglet weight at birth(WT0), at three weeks of age(WT3) and at weaned(WWT), piglet survival at birth(SURV1＝LSA/LS) and at three weeks of age(SURV2＝LSA/LS3). Results showed that sow breed effects was significant for littering traits considered and M sows had larger LS, LSA, LS3 and LSW than D females (P<0.001). However, piglets produced by D sows had heavier WT0, WT21 and WWT than those produced by M sows(P<0.001）. Also, the heterosis in LS3, LSW, SURV1, SURV2, LTRWT, WT0 and WT21 for MD and DM were significant (P<0.05）with estimates being 30.1%, 30.0%, 17.5%, 13.5%, 22.4%, 7.8% and 10.5%, respectively。

Key Words: Meishan pigs, Duroc pigs, Reciprocal crosses, Littering performances.