張秀鑾(1) 黃憲榮(2) 張伸彰(2) 許晉賓(2) 李世昌(1) 涂海南(2) 吳明哲(3)
DEVELOPMENT OF PROLIFIC LINE IN SWINE: VI.
LITTERING PERFORMANCES IN
F2 OF MEISHAN AND DUROC CROSSES
H. L. Chang(1), H. J. Huang(2), S. C. Chang(2), C. B. Hsu(2), S. C. Lee(1), H. N. Twu(2), M. C. Wu(3)
(1)Breeding and Genetics Division (2)
Kaohsiung Animal Propagation Station
(3) Hsinchu Branch, Livestock Research Institute, Council of Agriculture, Executive Yuan
The objective of this study was to evaluate the littering performances in F2 of Meishan (M) and Duroc (D) crosses for the reference of potential new breed/strain exploration in Taiwan. Parental stocks of tested animals were originated from MD (progeny of M sow sired by D boar) sows mated with MD or DM (progeny of D sow sired by M boar) boars, i.e., MDMD or MDDM genetic combination group in the F2 generation. Thus, all animals evaluated could be classified as one of the four genetic groups, which were from MDMD and MDDM crosses. A total of 37 boars and 119 sows were used to produce 202 litters. Littering traits evaluated were liter size at birth, born alive, at three weeks of age, and at weaned, litter weight and individual weight at birth, at three weeks of age and at weaned, and piglet survivability at birth and at three weeks of age. Results indicated that no significant genetic group effects on traits analyzed in this study except for piglet birth weight after records being pre-adjusted for farrowing season and sow’s parity. However, F2 sows produced larger litters in cool season than those in hot season (P<0.001), which was not the case in sows from previous generations. Parous sows produced more piglets than primarous ones (P<0.01) as expected.
Key words: Pig, Breed, Littering performances.