Prediction of goat litter size using body measurements

Résumé 0

"Changes in abdominal circumference (total and right half),live weight and vulva-cervix distance were used to predict thenumber of fetuses under range conditions. Total body weightgain during gestation was 5.49 ±2.3 and 6.9 ±2.9kg (mean±standard error) for single and twin-bearing does, respectively.The increment in abdominal circumference was 9.3 ±2.9 and10.6 ±3.3cm for single and twin-bearing does, respectively. Atthe end of pregnancy the vulva cervix distance was 3.0 ±1.6 and3.3 ±1.2cm for single and twin-bearing does, respectively. Discriminantanalyses on records of 97 goats indicated that at 68-90 days of pregnancy, live weight change was the best predictorvariable, with 62% being correctly classified as twin-bearingdoes. At 91-114 days of gestation abdominal circumference onaverage identified two thirds of twin-bearing does. At 115-142days of pregnancy live weight gain was again the best predictorvariable for separation of does according to number of fetuses.In all stages of pregnancy, the vulva-cervix distance was an erraticvariable for discriminating between single-and twin-bearingdoes. Little precision in predicting litter size was gained by combiningpairs of variables. It is concluded that change in abdominalcircumference at around 100 days of gestation is of moderatepractical significance for predicting multiple fetuses in goatsunder field conditions."