Impact of amino acid nutrition during lactation on body nutrient mobilization and milk nutrient output in primiparous sows.

Abstract

The impact of amino acid nutrition during lactation on body nutrient mobilization and milk nutrient output in primiparous sows was evaluated. Thirty-six sows, nursing litters of 13 pigs, were allocated daily 6 kg of a fortified corn-soybean meal diet containing a high (HP, 1.20% lysine) or low (LP, .34% lysine) protein content during a 23-d lactation. Dietary lysine concentration was achieved by altering the ratio of corn and soybean meal in the diet. The LP sows consumed less daily ME (14.2 vs 16.1 Mcal; P < .11) and daily lysine (16 vs 59 g; P < .01) than the HP sows. Daily litter weight gain was less (P < .01) for sows fed the LP vs HP diet, and the differences increased (P < . 01) as lactation progressed. The lower litter weight gain for the LP sows was reflective of the lower (P < .01) estimated milk DM, CP, and GE output of these sows. The LP sows lost more body weight (1.23 vs .21 kg/d; P < .01) during the initial 20 d of lactation. In the LP sows, 59% of the weight loss was protein, water, and ash, and 37% was fat. Weight loss in the HP sows was entirely accounted for by body fat mobilization, because these sows accrued body protein, water, and ash. Muscle myofibrillar breakdown rate was higher in LP sows than in HP sows (4.05 vs 2.80%/d; P < .01). On the basis of these data, dietary amino acid restriction during lactation increases maternal mobilization of proteinaceous tissue and reduces milk nutrient output. Maternal protein mobilization is maintained over the entire lactation even though milk output is decreased as lactation progresses.

Dietary protein restriction during lactation in primiparous sows with different live weights at farrowing: I. Consequences on sow metabolic status and litter growth

“…Energy restriction induces mobilization of both fat and protein reserves but has a limited influence on milk production, 40 H. Quesnel et al except in cases of extreme energy deficit and low or depleted body reserves. Low protein intake during lactation amplifies muscle protein mobilization [3][4][5]. It may compromise milk production in primiparous sows [4,6,7], but this effect of dietary protein restriction during lactation on litter growth is not always observed [8].…”

“…Low protein intake during lactation amplifies muscle protein mobilization [3][4][5]. It may compromise milk production in primiparous sows [4,6,7], but this effect of dietary protein restriction during lactation on litter growth is not always observed [8]. Such discrepancies between experiments could be explained by restriction intensity or by differences in sow body weight.…”

Dietary protein restriction during lactation in primiparous sows with different live weights at farrowing: II. Consequences on reproductive performance and interactions with metabolic status

“…The extent of body reserve mobilization depends on the amplitude and the nature of the nutritional deficit. Low protein supply during lactation amplifies muscle tissue mobilization [5][6][7]. In lactating primiparous sows, a severe deficit in dietary protein has been demonstrated to compromise lactation [6] and subsequent reproduction, especially the weaningto-estrus interval (WOI) [5,8,9].…”

“…Low protein supply during lactation amplifies muscle tissue mobilization [5][6][7]. In lactating primiparous sows, a severe deficit in dietary protein has been demonstrated to compromise lactation [6] and subsequent reproduction, especially the weaningto-estrus interval (WOI) [5,8,9]. However, this detrimental effect on WOI or ovarian function at weaning was not observed in primiparous sows that had large body reserves at farrowing [10,11].…”

Treonina digestível em rações para matrizes suínas em lactação

“…Estudando o impacto sobre a nutrição de aminoácidos durante a lactação, Jones & Stahly (1999) concluíram que a restrição de aminoácidos durante a lactação aumenta a mobilização de tecido protéico de matrizes suínas.…”