Evaluation of three-ram cohort serving capacity tests as a substitute for individual serving capacity tests.

摘要: Alternatives to time-consuming, labori- ous individual serving capacity tests (ISCT) are need- ed classify ram sexual behavior. The objective of study 1 was evaluate the relationship between first 3-ram cohort test (COSCT) scores and mean 5 ISCT scores. 2 de- termine whether or additional COSCT improved ability predict For 1, rams (n = 69) were assigned either a given be- fore after 9 ISCT. 2, 127) 3 before 6 repeated COSCT, initially grouped at random subsequently rerandomized so that each with least different for test. both studies, number ejaculations from compared across second through sixth A threshold tween high- low-performing defined in analysis as sexually ac- tive rams. Rams greater than classified having high activity, whereas below low activity. no inactive. Data studies used multiple fit various models determine wheth- er COSCT. best model piecewise linear regression model. correctly identified all inactive studies. however, also 56% active 18% had 71% probability activity if they We conclude single is reliable, albeit more conservative, efficient alternative series characterizing Multi- ple can provide some protection against culling (i.e., approximately 50% less COSCT) still retain most efficiency It important use high-performance breeding because will double ewes bred lambs sired low-performance large need be serviced daily.