24 Effects of Spring versus Fall Calving on Fetal Growth, Vigor at Birth, and Neonatal Circulating Metabolites in Beef Calves. (7th May 2021)

• Record Type: Journal Article
• Authors: Wichman, Lindsey G; Redifer, Colby A; Meyer, Allison M
• Is Part Of: Journal of animal science. Volume 99(2021)Supplement 1
• Page Start: 23
• Page End: 24
• Publication Date: 2021-05-07
• Subjects: calving -- metabolites -- neonate; Livestock -- Periodicals; Livestock; Electronic journals; Periodicals; 636.005
• DOI: 10.1093/jas/skab054.041
• Languages: English
• ISSNs: 0021-8812

Abstract

Abstract: To determine the effect of season on perinatal nutrient availability, assessed through fetal growth, calf vigor, and neonatal circulating metabolites, multiparous and primiparous dams (age: 4.7 ± 2.4 yr; BCS: 5.3 ± 0.6) from 4 spring (2014–2017; n = 202) and 4 fall (2015, 2017–2019; n = 177) calving experiments were observed during parturition. Time to stand (spring: 67; fall: 104) was determined as minutes from birth to standing for 5 sec. After birth, calf BW and size (spring: 99; fall: 169; length, heart girth, abdominal girth, and cannon circumference) were recorded. Jugular blood samples were obtained from 63 spring and 89 fall calves at 0 (pre-suckling), 6, 12, 24, and 48 h postnatally. Data were analyzed either with the fixed effect of season (single point) or the fixed effects of season, hour, and their interaction with hour as a repeated effect (over time); calf sex was included when P < 0.25. Experiment was a random effect. Fall-born calves tended to have lighter (P = 0.09) BW and faster (P = 0.05) time to stand than spring-born calves. Season did not affect (P ≥ 0.18) other calf size measures. The season x hour interaction (P ≤ 0.07) affected circulating glucose, non-esterified fatty acids (NEFA), triglycerides, urea nitrogen, globulin, and total protein. Spring-born calves had greater (P ≤ 0.009) 0 h glucose, 0 and 6 h NEFA, and 0, 6, 12, and 48 h triglycerides than fall-born calves. Fall-born calves had greater (P = 0.03) total protein at 24 h and tended to have greater (P ≤ 0.10) total protein and urea nitrogen at 48 h and globulin at 24 h. Season affected albumin, which was greater (P = 0.003) in fall-born calves. These data suggest that calving season influences perinatal nutrient availability, which may impact the transition to postnatal life.