Feeding strategy during pregnancy for ewes with a large litter size. 2. Effect on blood parameters and energy status.

Abstract

In 6 feeding trials with pregnant ewes, blood glucose concentrations were affected by litter size after day 84 of pregnancy. An increase in litter size decreased blood glucose during the last phase of pregnancy. At day 141 a sharp increase in glucose was seen. Ewes with ketosis had after day 126 of pregnancy a significant lower glucose concentration. beta -Hydroxybutyrate (BHB) and non-esterified fatty acids (NEFA) were also affected by litter size in the last months of pregnancy. With increasing litter size BHB increased more dramatically than NEFA concentrations. Ewes with ketosis had higher BHB and NEFA concentrations in the last month of pregnancy. Ewes on treatments with a higher metabolizable energy (ME) intake (rations with 60% of the energy originating from concentrates) had a higher glucose, a lower BHB and a lower NEFA concentration in the last month of pregnancy than ewes given a diet with 40% of the energy originating from concentrates. A lower incidence of ketosis on treatments with a higher energy intake was expected, but not seen. Probably, energy deficit is not the only factor inducing ketosis. With regression models the energy requirement of pregnant ewes with a body weight of about 85 kg during the last month of pregnancy was estimated. ME requirement in MJ per day for a ewe with a single, twin, triplet, quadruplet and quintuplet was 13.0, 15.9, 17.1, 18.4 and 19.1, respectively. The estimated energetic efficiency of conceptus growth was about 0.16. (Abstract retrieved from CAB Abstracts by CABI’s permission)

Triplet lambs and their dams – a review of current knowledge and management systems

“…They suggested that this reduction in intake with larger litter sizes was potentially explained by; reduce abdomen space due to rapid uterine expansion, greater heat stress from more lambs in the uterus especially in ewes with an intact fleece, higher levels of oestrogen which has been shown to reduce intake, and a ewe in an energy deficit state is driven to energy mobilisation resulting in increased levels of free fatty acids which could result in reduced intake. Everts (1990b) and Fogarty et al (1992) reported that glucose levels were negatively affected by litter size after mid-pregnancy. In addition, triplet-bearing ewes in late pregnancy display higher ketone, Beta-hydroxybutyrate (BHB) and non-esterified fatty acid (NEFA) concentrations than twin-bearing ewes (Barlow et al 1987;Morris and Kenyon 2004;Corner et al 2008;Kenyon et al 2010aKenyon et al , 2010b.…”