Effect of Condition of Sows on Energy Balances during 7 Days before and 7 Days after Parturition

Energy Metabolism During Late Gestation and Lactation in Muciparous Sows in Relation to Backfat Thickness and the Interval from Weaning to First Oestrus

“…Catabolism during the same period in the L-group was less pronounced. Similarly, it was found that during the first 10 days postpartum, the energy balance of thin sows was less negative than that of sows in normal condition (de Lange et al 1980). As lactation proceeded concentrations of free fatty acids and creatinine decreased, while those of triglycerides stabilized in both groups, indicating that the metabolism was becoming more balanced.…”

“…Initially, this increase might be due to a rise in the cortisol concentration at parturition (Molokwu et al 1973), while suckling-induced releases of oxytocin (Forsting et al 1979), gastrin (Uvniis- Moberg et al 1984) and glucagon (Eriksson et al 1987, Algers et al 1989 might account for the increase as lactation proceeds. Nitrogen retention has been shown to occur during the week before parturition in both poorly fed, thin sows and in adequately fed sows in normal condition (de Lange et al 1980). Nitrogen is mainly deposited as foetal protein during late pregnancy and deposition is much lower in the maternal tissue of pregnant animals than in nonpregnant animals (Close et al 1985).…”

“…The fact that weight loss was initially more pronounced in the H-group suggests that the higher urea concentration in sows in this group was due to their higher rate of maternal protein mobilization. Thin, multiparous sows have been shown to lose less nitrogen during the first week of lactation than normal sows fed the same ration (de Lange et al 1980). Creatinine is the end product of muscle catabolism and increases in connection with the wasting of muscle tissue (Wallach et al l 978).…”

Effect of feeding level on milk production of sows during four weeks of lactation.

“…about 1500 kJ ME/kg 3/4 ) of feed was based on the assump tion that the main part of milk would be produced from feed. This was obtained by supplying maintenance (assumed 420 kJ ME/kg 3/4 ) and, in addition, feed for milk production assuming arbitrarely an efficiency of 60 % for conversion of metabolizable energy from feed into milk energy (de Lange et al, 1980). Since animals will produce more milk at higher intake levels it was decided to aim at an intake of near ly ad libitum (5 kg/day in the period from 7 to 14 days post partum and 5.5 to 6 kg/ day in the period of 18 to 25 days post partum).…”

“…Most studies have been performed with the assumption that change in body weight of the sows can be used as an estimate for changes in energy content of the body (Bowland, 1967;Aherne & Speer, 1974). De Lange et al (1980) have estimated that milk in sows was produced with an efficiency of 48 to 70 % from metabolizable en ergy in feed or from energy stored in the body. Compared with cows, however, esti mates from sows are more difficult to make due to errors associated with milk pro duction determination and with obtaining a correct sample (den Hartog et al, 1984).…”