Effect of weaning weight, environmental temperature and dietary energy level in newly-weaned piglets

Abstract

This research was developed to evaluate the effect of weaning weight (WW) (4.0 ± 0.7 kg and 6.3 ± 0.6 kg), environmental temperature (ET) (29 ± 1.74 ^oC and 25 ± 1.3 ^oC) and dietary ME level (DME) (3250, 3400, 3550 or 3700 kcal of ME/kg) on performance, digestibility of nutrients, gross energy  metabolizability (GEM) and nitrogen retention (NR) for newly–weaned piglets. In the period, from 1 to14 days after weaning, sixty four hybrid piglets were allotted on metabolic cages (two animals/cage) and in the period from 15 to 28 days after weaning, 32 piglets were kept individually housed in the same cage. In the total period, there was a significant interaction between WW and DME for feed: gain ratio (FGR) with the heavy piglets presenting better FGR in response to increase of DME. Piglets with lower weight had higher feed: gain ratio and weight gain and feed intake reduced. Piglets allotted in  environment with 25 ^oC showed greater WG and FI. There was no effect of DME on performance evaluated. In the total period, apparent digestibility of dry matter, crude protein, gross energy and crude fat, NR and GEM showed linear effect by increased of DME. In all metabolic parameters, the animals kept at 25 ^oC of ET had lower values than the animals kept at 29 ^oC. WW had no influence on metabolism of nutrients.