The influence of gestation feeding strategy on body composition of gilts at farrowing and response to dietary protein in a modified lactation.

Abstract

Previous experiments have indicated that reproductive function in lean, modern genotypes may be more dependent on body protein mass than, as previously believed, on body lipid reserves. This was investigated in a 3 x 2 factorial arrangement of treatments, involving 60 first-parity sows, comparing three pregnancy feeding strategies and two lactation diets. During pregnancy, sows were fed either a basal diet (5 g lysine/kg, 13 MJ of DE/kg [C]) or the same quantity of basal diet + energy source [E], or additional basal diet supplying both protein and energy [A]. The level of supplement for E and A was adjusted weekly to achieve a backfat thickness measurement (P2 position) of 28 mm at farrowing. Isoenergetic lactation diets were fed to appetite and provided either high (180 g CP/kg, 9 g lysine/kg [H]) or low lysine (120 g CP/kg, 6 g lysine/kg [L]). From d 21 of lactation, sows were separated from their litters and housed next to a boar for 8 h each day; final weaning occurred on d 31. Pregnancy treatment differences in backfat and weight were achieved, with C sows having less backfat on d 1 of lactation than E and A sows (E = 28.1, A = 28.0, C = 22.7 kg, P < 0.001). Sows fed additional basal diet were heavier than E sows, which were heavier than C sows (E = 190, A = 201, C = 178 kg, P < 0.001). Average feed intake over lactation showed a pregnancy feeding effect, with E sows eating less than A or C sows (E = 4.9, A = 5.2, C = 5.4 kg/d, P < 0.005). Total lactation weight loss was affected by pregnancy feeding (E = 18.0, A = 19.0, C = 8.4 kg, P < 0.05) and by lactation diet (L = 19.0, H = 11.3 kg, P < 0.05), whereas total lactation backfat loss was affected only by pregnancy treatment (E = 6.9, A = 6.5, C = 4.6 mm, P < 0.05). No pregnancy treatment or lactation diet effects were observed for litter performance. Lactation diet affected weaning-to-estrus interval, with more sows on the H diet coming into estrus within 6 d of partial weaning (P < 0.05), but there was no pregnancy treatment effect. Therefore, voluntary feed intake during lactation was suppressed by increased fat reserves at a limited body protein mass but not when body protein mass was also increased. Partial weaning-to-estrus interval was increased by reduced dietary protein.

Metanálise da relação entre espessura de toicinho e variáveis corporais e reprodutivas de porcas gestantes e lactantes

“…Foram utilizados 14 artigos distribuídos nos continentes europeu e americano, publicados de 2000 a 2006 em revistas indexadas internacionais (PRUNIER et al, 2001, SINCLAIR et al, 2001COOPER et al, 2001a, CLOWES et al, 2003MAES et al, 2004;RAMANAU et al, 2004;VAN DER PEET-SCHWERING et al, 2004;YOUNG et al, 2004;RENSIS et al, 2005;YOUNG et al, 2005b;LANDBLOM et al, 2006) e nacionais (GUEDES & NOGUEIRA, 2000;HASHIMOTO et al, 2004;LIMA et al, 2006). As informações relevantes das seções de material e métodos e resultados de cada artigo foram inseridas numa base de dados elaborada em planilha Excel.…”

Metanálise da relação entre espessura de toicinho e variáveis nutricionais de porcas gestantes e lactantes

“…O conteúdo de gordura e proteína no leite é influenciado pela dieta lactacional; logo, níveis elevados de proteína na dieta resultam em maior percentagem de gordura e proteína no leite (SINCLAIR et al, 2001).…”

“…Foram utilizados 14 artigos publicados de 2000 a 2006, em revistas indexadas internacionais (PRUNIER et al, 2001;SINCLAIR et al, 2001;COOPER et al, 2001;CLOWES et al, 2003a;MAES et al, 2004;RAMANAU et al, 2004; VAN DER PEET-SCHWERING et al, 2004;YOUNG et al, 2004;RENSIS et al, 2005;YOUNG et al, 2005b;LANDBLOM et al, 2006) e nacionais (GUEDES & NOGUEIRA, 2000;HASHIMOTO et al, 2004;LIMA et al, 2006). As tabelas do NRC (1998) e de ROSTAGNO et al (2000) foram avaliadas juntamente com os resultados da metanálise.…”

Gestational and lactational feeding strategies for gilts: Growth, carcass characteristics and meat quality of the progeny

“…However, long-term effects on the progeny, i.e., whether the differences at weaning were still evident at market weight and/or whether they affected carcass and pork quality, were not investigated in their study. Sinclair et al (2001), on the other hand, showed no significant effect of energy or protein intake during pregnancy on piglet growth. This difference between experiments may be due to the lower nutritional drain in lactation of the sows in the experiment of Sinclair et al (2001), so any effects of the gestational feeding strategy were masked.…”

“…Sinclair et al (2001), on the other hand, showed no significant effect of energy or protein intake during pregnancy on piglet growth. This difference between experiments may be due to the lower nutritional drain in lactation of the sows in the experiment of Sinclair et al (2001), so any effects of the gestational feeding strategy were masked. In the experiment of Sinclair et al (2001), gilts were fed more total lysine (31 or 47 g d -1 vs. 6 to 30 g d -1 ) in lactation, but their litters grew more slowly (about 1.6 vs. 2.0 kg d -1 ) than those in the experiment of Kusina et al (1999).…”