Interactions between weaning age, weaning weight, sex, and enzyme supplementation on growth performance of pigs

Abstract

Digestive capacity of early-weaned pigs may be insufficient to fully digest many ingredients currently used in weaner diets. The aim of this experiment was to determine whether an exogenous enzyme preparation with broad carbohydrase activity could benefit pigs that developmentally might be immature at weaning, especially with regard to gastrointestinal development. Eighty Large White × Landrace pigs were used in a 2 × 2 × 2 × 2 factorial experiment with the factors being: weaning age (14 or 24 days), weaning weight (heavy or light), sex (boar or gilt), and dietary Biofeed Plus CT (0 or 500 μg/g) which contained fungal xylanases, pentosanases and β-glucanases. Pigs were housed individually and given a wheat-based (550 g/kg) diet containing 15.0 MJ DE and 15.9 g lysine/kg on an ad libitum basis for 21 days. The diet also contained 50 g/kg of soybean meal and 50 g/kg of lupin (Lupinus�angustifolius) kernels. The liveweights of heavy (H) pigs weaned at 24 or 14 days and light pigs (L) weaned at 24 or 14 days were 7.9 and 5.3 and 5.2 and 3.9 kg, respectively. Pigs weaned at 14 days grew slower (157 v. 345 g/day) than those weaned at 24 days, although there was a suggestion of an interaction between age and weight at weaning (P = 0.081). Thus, H and L pigs weaned at 14 days grew at 148 and 166 g/day, whereas H and L pigs weaned at 24 days grew at 374 and 315 g/day, respectively. Although there was no main effect of enzymes on daily gain (248 v. 254 g/day, P = 0.80), feed intake (278 v. 284 g/day, P = 0.79), or feed conversion ratio (1.19 v. 1.25, P�=�0.35), there were interactions with weaning age on daily gain (P = 0.050) and feed intake (P = 0.060). Pigs weaned at 14 days grew slower (176 v. 138 g/day) and ate less (206 v. 174 g/day), whereas pigs weaned at 24 days grew faster (321 v. 369 g/day) and ate more (351 v. 394 g/day), when supplemented with enzymes. During the third week after weaning there were interactions between dietary enzymes and sex (P = 0.060) and dietary enzymes and age (P = 0.023) on daily gain. Thus, pigs weaned at 24 days and supplemented with Biofeed Plus CT grew more quickly during the third week (559 v. 460 g/day), whereas the converse was true for pigs weaned at 14 days (286 v. 334 g/day). Also, enzyme-supplemented boars grew better over this period (457 v. 371 g/day), whereas the converse was true for gilts (388 v. 423 g/day). In conclusion, these data clearly indicate that the greatest determinant of post-weaning performance under the present conditions was the age of the pigs at weaning. Dietary enzyme supplementation appeared most efficacious in boars weaned at an older age, although benefits did not become apparent until 2 weeks after weaning.

Age, sex, and weight at weaning influence organ weight and gastrointestinal development of weanling pigs

“…In the current study, the activities of trypsin, amylase, colipase, and lipase were expressed per gram of pancreas in order to standardise enzyme measurements, because pancreatic weights were influenced by all factors in the study except gender (Table 3). Increased trypsin activity in pigs weaned at 28 days of age and in heavier pigs might partly explain why these pigs perform better after weaning than pigs weaned at 14 days of age or which are light-for-age (Dunshea et al 2003a). There was no increase in the specific activity of amylase after weaning; however, Cranwell et al (1997) showed an increase in the total activity of amylase in the pancreas with time after weaning.…”

“…at 14 days of age. This most likely reflected the greater level of voluntary feed intake seen in pigs weaned at an older age (Dunshea et al 2002(Dunshea et al , 2003b. Cranwell (1995) summarised data from numerous studies highlighting the rapid growth of gastrointestinal organs after weaning, and concluded that the weaned pig requires a relatively larger digestive system than a sucking pig to satisfactorily digest and absorb the inherently less digestible diets offered after weaning, and maintain a commercially acceptable level of performance.…”

“…However, provision of a dry solid diet on an ad libitum basis, as opposed to a milk liquid diet, fails to mitigate villous atrophy and crypt elongation after weaning, which suggests that a component of the adaptive response of digestive and absorptive function following weaning is independent of nutrient intake (Kelly et al 1991a, 1991b: McCracken et al 1995Pluske et al 1996aPluske et al , 1996b. Nevertheless, it has been reported previously that pigs weaned heavier and at an older age eat more dry feed after weaning than pigs weaned lighter and at an earlier age (Dunshea et al 2002(Dunshea et al , 2003b. This increased intake might cause a reduction in the number of days that the older/heavier pigs take to reach slaughter weight (Dritz et al 1996).…”

Production levels and health status in Iberian piglets at weaning1

“…Growth rates may be different in early weaned piglets compared with those with a more prolonged lactation period (Dunshea et al, 2002;Sharon et al, 2003;Main et al, 2004), and intestinal development in piglets late weaned may be more advanced (Callesen et al, 2007;Wellock et al, 2007). This situation has been described extensively in the literature that compared different weaning ages, and in most of them, late weaning showed better results than early weaning.…”

“…This situation should not pose major problems as long as the growing pig has the ability to digest, absorb, and use the nutrients provided in its new diet. Nevertheless, piglets have a reduction in absorption capacity after weaning, and weaning age can markedly affect the ability of weaned piglets to adapt to the dietary changes associated with weaning (Dunshea et al, 2002;Sharon et al, 2003;Main et al, 2004;Callesen et al, 2007;Wellock et al, 2007).…”