Body condition status at mating affects gestation length, offspring yield and return rate in ewes

Abstract

Abstract. The present study was planned to determine the effect of ewe body condition score (BCS) and parities on fertility, return rate, gestation length, fecundity, litter size and lamb birth weight. Data were collected from 284 heads of ewes with first to fifth parity and raised at a state farm for three consecutive (2002)(2003)(2004) years. Teaser rams were used to monitor estrus twice daily in the morning and in the evening from September to October. BCSs and body weights (BWs) were recorded at mating and postpartum. The ewes, at mating time in breeding season and within first 6 h after the expulsion of fetal membranes, were divided into four groups on the basis of their BCS: thin (BCS = ≤ 2.0; n = 70; 38), medium (BCS = 2.5-3.0; n = 122; 142), fat (BCS = 3.5-4.0; n = 72; 59) and very fat (BCS = ≥ 4.5; n = 20;17). BCSs and BWs of ewes at postpartum were highly correlated with lamb birth weight (R = 0.486, P < 0.01, and R = 0.130, P < 0.05, respectively). BCSs and BWs of ewes at postpartum had positive effects on lamb birth weight (Y = 3.43 ± 0.10 + 0.130 + 0.047 ewe body condition score (EBCS), P < 0.01; Y = 2.92 ± 0.42 + 0.018 ± 0.009 ewe body weight (EBW), P < 0.05 kg of lamb birth weight per BCS and kilogram of ewe live weight, respectively). The fertility rate, litter size and fecundity were higher in the medium and fat groups than thin and very fat groups (χ 2 = 10.607, P < 0.01). The BW and BCS at postpartum affected gestation length positively (P < 0.05). Return rate or number of coitus for conception were higher (P < 0.05) in thin and very fat groups than medium and fat groups. The data revealed that the ewes with medium and fat body condition (BCS = 2.5-4.0) scores were profitable.

Relationship between the animal body condition and reproduction: the biotechnological aspects

“…Comparison of groups Q1 and Q4 revealed a higher proportion of transferable embryos (83.8 % vs. 53.2 %) and a lower proportion (9.6 % vs. 35.2 %) and count (0.6 % vs. 2.7 %) of degenerated embryos in the Q1 group (smallest change). In conclusion, the authors concluded that these results are in compliance with the idea that a lower BCS at the time of the first insemination is associated with fertility decline (Carvalho et al, 2014).…”

“…Relationships between fertility and changes in body weight (BCS) were also the subject of the study by Carvalho et al (2014). The authors divided the cows at the postpartum period into four quartiles (Q) that presented changes (%) in body weight (Q1 indicates the smallest change; Q4 indicates the biggest change).…”

A Case Study of Bear Reintroduction in Pakistan: Art and Politics in Conservation

“…Contrary to this, Mithuna et al (2015) reported that pre-partum concentrate supplementation (2 kg/d) had higher (24.33 vs. 28.00 kg) birth weight of buffalo calves as compared to nonsupplemented group. This contradiction might be due to fact that BCS of buffaloes during gestation and at calving was higher in present study, as the higher BCS at mating and during pregnancy results in higher birth weight and return rate compared to thin (Low BCS) animals (Cam et al 2018). Moreover, birth weight of calves in our study were also higher (ranged 30.3 to 33.5) compared to the study by Mithuna et al (2015) and close to the birth weight reported by Naqvi and Shami (1999) in Nili Ravi buffalo calves.…”

Abstracts from the Proceedings of the 33rd Biennial Conference of the Australian Association of Animal Sciences

“…This critical level can be reached through provision of adequate nutrition to ensure the appropriate LW/BCS at time of joining. Reproductive output of the ewe and progeny growth and survival can also be improved through improving LW/BCS at joining (Cam & Kirikci 2018), during early-mid (Paganoni et al 2014) and late pregnancy (Behrendt et al 2019).…”