The influence of maternal nutrition on muscle fiber number development in the porcine fetus and on subsequent postnatal growth1

Abstract

In the pig, undernutrition in utero causes low birth weight, a decrease in muscle fiber number, and a reduction in postnatal growth rate. The effect on fiber number is mediated via a reduced secondary fiber population. Within a litter of pigs, lighter-weight pigs have probably suffered some deficit in muscle fiber number. In an attempt to improve the number of fibers in the lighter-weight pig fetuses, four maternal feeding regimens were used, one serving as the control. Maternal feed intake was doubled for one of three time periods during pregnancy: 1) d 25 to 50 (HE) immediately before fiber hyperplasia; 2) d 50 to 80 (HL) during fiber hyperplasia; or 3) d 25 to 80 (HT) covering both developmental events. Controls were fed at levels routinely used for pregnant sows on the farm. Sows farrowed normally and pig birth weights were recorded. Estimates were made of total myofiber number, total primary fiber number, and mean secondary:primary fiber number ratio (S:P) for the semitendinosus of each pig at 5 wk postnatal or 80 kg (HT and two control litters only). The progeny of all supplemented sows had a significantly greater mean S:P ratio (P < .05), and the HE pigs tended to have a greater number of muscle fibers than control pigs (403,840 +/- 8,197 vs 370,970 +/- 12,720). Postnatal growth rate to 80 kg was also investigated for the HT group of pigs.(ABSTRACT TRUNCATED AT 250 WORDS)

Effects of supplemental feeding on performance of Kilis goats kept on pasture condition

“…The current results regarding kid growth emphasised the importance of additional feeding before mating and during lactation in extensive goat farming (Martin et al 2004;Scaramuzzi et al 2006;Sultana et al 2012). It has been reported that the nutritional level in maternal feeding during pregnancy affected the number of secondary muscle fibres in striated muscle tissue in foetus which had an effect on birth weight (Dwyer et al 1994;Tygesen & Harrison 2005;Tygesen et al 2007). Also, as given in Table 6, weaning kids from treatment goats were heavier than those of control goats (p<0.05).…”

Key signalling factors and pathways in the molecular determination of skeletal muscle phenotype

“…However, in the context of foetal fibre number, the precise role of maternal nutrition is not entirely clear. Earlier work suggests that doubling food intake during early sow pregnancy increases the number of secondary fibres in the newborn, which would confer greater potential for post-natal growth (Dwyer et al, 1994). More recent work, however, could not reproduce this finding (Nissen et al, 2003).…”

Growth and development of offspring following supplementation of sow diets with oil during mid to late gestation

“…Age and weight prior to slaughter, growth rates between birth and slaughter and eye muscle depth at the P2 position were similar, irrespective of maternal diet. These results are unsurprising, since body weight was the criterion on which pigs were selected for slaughter, the growth rates of pigs were similar throughout the neonatal period, and the programming of lean growth potential is thought to occur during early-mid gestation (Dwyer et al, 1993 and1994). The offspring of C and S sows possessed more fat at the P2 position prior to slaughter; this was surprising because the S group exhibited the slowest rate of fat accretion during the pre-weaning period.…”