Clark L K, Schinckel A P, Singleton W L, Einstein M E, Teclaw R F
Department of Large Animal Clinics, School of Veterinary Medicine, Purdue University, West Lafayette, IN 47907.
J Am Vet Med Assoc. 1989 Jan 15;194(2):239-43.
The first 100 single-boar services of 140 boars were analyzed to determine whether the farrowing rate resulting from initial services predicted the farrowing rate of subsequent services. The data were analyzed for the influence of parity, number of matings per estrus, season of service, and interaction of these variables on farrowing rate. Sow parity influenced farrowing rate. Sows with parity greater than 8 and gilts had the lowest farrowing rates (P less than 0.01). Sows with parity 2 through 5 had the highest farrowing rates (P less than 0.01). One and 2 matings/estrus resulted in reduced farrowing rates (P less than 0.01), compared with farrowing rates of greater than 2 matings/estrus. Farrowing rate for services during the summer was lower than that for other seasons of the year (P less than 0.01). Evidence of interaction among these variables was not found. Therefore, the results of each service recorded was adjusted to the mean farrowing rate of sows with parity 2 through 5, sows mated greater than or equal to 3 times/service, and sows serviced in the spring. After these adjustments, the farrowing rates for the first 10, 20, 30, 40, and 50 services were analyzed to determine associations with farrowing rates for subsequent services through 100 farrowings. These data also were analyzed to determine whether the associations were strengthened by removal of the first 10 services from the data. The best farrowing rate association indicated that for each 1% increase in farrowing rate subsequent to the first 50 services, the farrowing rate for the second 50 services increased 0.33% (P less than 0.01).(ABSTRACT TRUNCATED AT 250 WORDS)
对140头公猪的前100次单公猪配种服务进行分析，以确定首次配种的产仔率是否能预测后续配种的产仔率。分析了胎次、每次发情期配种次数、配种季节以及这些变量的相互作用对产仔率的影响。母猪胎次影响产仔率。胎次大于8的母猪和后备母猪产仔率最低（P<0.01）。胎次为2至5的母猪产仔率最高（P<0.01）。与每次发情期配种次数大于2次的产仔率相比，每次发情期配种1次和2次会导致产仔率降低（P<0.01）。夏季配种的产仔率低于一年中的其他季节（P<0.01）。未发现这些变量之间存在相互作用的证据。因此，将记录的每次配种服务结果调整为胎次为2至5、每次配种次数大于或等于3次以及在春季配种的母猪的平均产仔率。进行这些调整后，分析前10次、20次、30次、40次和50次配种服务的产仔率，以确定与后续100次产仔的配种服务产仔率之间的关联。还对这些数据进行分析，以确定去除数据中的前10次配种服务后，这种关联是否会增强。最佳的产仔率关联表明，在前50次配种服务之后，产仔率每增加1%，后50次配种服务的产仔率就会增加0.33%（P<0.01）。（摘要截短至250字）
