The primary objective of this Australian Wool Education Trust funded teaching initiative on inquiry-based learning and research-led teaching approach was to enhance students’ critical thinking and target their learning needs through active participation in hands-on experience with experimental sheep. The secondary objective was to study the effects of sire breed and sex on growth and body conformation traits in crossbred prime lambs at the University of Tasmania Farm, Cambridge. Body weight, average daily gain, body condition score, body length, withers height and chest girth in sixty first cross Merino lambs sired by White Suffolk and Poll Dorset rams were measured fortnightly over a ten-week period. Generalised linear model procedure in SAS was used for statistical analysis and included the fixed effects of sire breed, sex, fortnight and their second order interactions. Duncan’s Multiple Range Test, correlations between growth and conformation traits and Bonferroni probabilities were estimated and used for comparisons.
A fortnightly increase in lamb body weight, average daily gain and body condition score was evident. Wethers were heavier and had higher average daily gains than ewes. White Suffolk sired progeny had higher average daily gains than those sired by Dorset rams, but body weight did not differ between sire breeds. However, a highly significant interaction (P<0.0001) between sire breed and sex on body weight was evident as White Suffolk sired wethers were the heaviest prime lambs. It was concluded that the real world, hands-on research experience with experimental sheep, field trips, data collection, statistical analyses, data interpretation and seminar presentation of results facilitated a deeper student understanding of the scientific concepts of sire genetics and nutrition interactions in sheep growth.