The effect of pregnancy, energy intake and mating weight on protein deposition and energy retention of female pigs

Abstract

1. In a comparative slaughter experiment, 12 female pigs (six at 80 kg and six at 100 kg) were allocated at first oestrus to each of five treatments: Treatment 1 initial slaughter, or Treatments 2, 3 and 4 mated and given 19-5, 25-8 or 32-1 MJ ME/day for the last 100 days of pregnancy, or Treatment 5 not mated (virgin) and given 25-8 MJ ME/day over a similar period. Pigs on Treatments 2, 3,4 and 5 were given the same amount of protein and were killed about 123 days after first oestrus. Piglets were removed at birth. 2. Total protein deposition (carcass+viscera+piglets) was increased from a total (±SE) of 5-50 to 8-47 (±0-43) kg as ME intake was increased from 19-5 to 32-1 MJ ME/day. About 75 % of the increase in protein deposition was in the carcass component. The average response to ME was 2-2 + 0-58 g total protein deposition per MJ increment in ME. 3. The once-mated pigs deposited similar amounts of total protein to the virgin pigs but significantly less (P<0-05) carcass protein, when this was corrected to the same amount of carcass fat deposition. 4. Increasing energy intake from 19-5 to 32-1 MJ ME/day increased total fat deposition from 2-8 to 16-0 kg. The average response to ME was 13-5 + 1-53 g fat deposited per MJ increment in ME. 5. There were no significant differences between the once-mated and virgin pigs in their calculated maintenance requirement, nor in the efficiency with which ME surplus to requirement for maintenance was utilized for energy retention. The average maintenance requirement for all pigs was 530 (95 % limits 303-882) kJ/kgoss. day. The average efficiency of utilization of ME for energy retention was 58-5 ±6-2%. 6. There was no evidence of any pregnancy anabolism other than that involving the conceptus, the needs of the dam specific to pregnancy and preparation for lactation.

Effets d'une réduction de l'apport protéique durant la gestation sur le métabolisme maternel et l'évolution de la composition corporelle au cours du cycle de reproduction chez la truie

“…On sait, en effet, que la croissance prépubertaire peut affecter les potentialités de dépôt protéique au cours de la gestation (D UEE , T REIL & C AMOUS , 1980). Par ailleurs, les observations de H OVELL et al (1977), réalisées 9 jours après le part peuvent masquer l'effet propre de La gestation sur la composition corporelle des animaux. Quoique l'analyse chimique n'ait pas été réalisée, on peut penser que le dépôt accru de muscles implique un dépôt protéique supplémentaire (reflété par le bilan azoté à 80 jours).…”

Influence de l'alimentation des truies gravides sur l'évolution des réserves corporelles maternelles et le développement de la portée

“…However (Rombauts, 1962). Aussi, pour ces animaux, l'améliora-tion de la rétention azotée avec l'avancement de la gestation n'apparaît pas nettement (Etienne et Henry, 1973 (Kotarbinska et Kielanowski,1973;Brooks et al, 1975 ;Hovell et al, 1977 (Holden et al,1968 ;Baker et al1970 ;Mahan et Mangan, 1975).…”