Location: Livestock Bio-SystemsTitle: The relationship between milk score near parturition and udder score near weaning and their effects on Polypay, Rambouillet, and Targhee ewe productivity
Submitted to: Translational Animal Science
Publication Type: Proceedings
Publication Acceptance Date: 9/23/2021
Publication Date: 11/30/2021
Citation: Murphy Jr, T.W., Taylor, J.B. 2021. The relationship between milk score near parturition and udder score near weaning and their effects on Polypay, Rambouillet, and Targhee ewe productivity. Translational Animal Science. 5(Supplement S1): S134-S138. Article txab176. https://doi.org/10.1093/tas/txab176.
Technical Abstract: Ewe milk production explains a substantial amount of variation in lamb growth but improving it likely has diminishing economic returns in nutrient limited, forage-based sheep systems. Furthermore, unfavorable relationships between milk production and udder conformation have been reported in dairy sheep but have not been extensively evaluated in range type ewes. Historical records of subjective milk score near lambing, udder score near weaning, and total litter weaning weight (LWW) were evaluated for Polyay (n = 8107), Rambouillet (n = 7046), and Targhee ewes (n = 8553). Across breeds and ages, LWW was greatest for high (56.7 to 65.3 kg), intermediate for average (53.3 to 61.7 kg), and least for low milk score ewes (47.2 to 55.7 kg; P < 0.001). Interestingly, LWW was greater for ewes with pendulous udders (58.4 to 64.8 kg) than normally shaped udders with active (52.4 to 60.7 kg) or inactive mammary tissue (47.5 to 56.9 kg; P < 0.001). However, ewes displaying pendulous udders should be culled to avoid complications in subsequent lactations. Moreover, the risk of recording pendulous, asymmetric, or damaged udders at weaning was 1.8 to 2.2 and 1.5 to 1.8 times greater for ewes with high than low or average milk scores at parturition, respectively. Results suggest milk production is an important component of ewe productivity but should be jointly considered with indicators of udder conformation and health.