Desempenho zootécnico de suínos nas fases de crescimento e terminação submetidos a diferentes programas de iluminação em ambientes climatizados

Abstract

The experiment was conducted in the Swine Sector of UFRPE / UAST. Twenty-seven piglets, castrated male and female, from Pietrain-Duroc matrices, with initial weight of 38.1 ± 4.2 kg were used. The experimental design was completely randomized, in a 3 x 3 factorial arrangement, with 27 animals randomly distributed in nine bays with three air conditioning systems and three light supplementation programs, considering three replications per treatment. Feed and water were provided at will and the diets for each evaluation period were formulated with corn and soybean meal in order to meet the nutritional requirements of the animals (growth and finishing stages). The animals were weighed and housed in stalls with a ceramic tile roof, providing 6.0 m² of floor space, containing a semiautomatic type feeder and a pacifier-type waterer at a height of 40 cm from the ground in each bay. The pigs were weighed weekly and rations and leftovers were weighed daily (morning and afternoon) to evaluate performance parameters: weekly weight gain, total weight gain, daily feed intake and mean feed conversion. The performance parameters were analyzed using the SAS® GLM procedure and the comparison of the means, when necessary, were performed by the Tukey test at 5% probability. In the 30 to 50 kg (CRES I), 51 to 70 kg (CRES II) and 71 to 90 kg (TERM) phases, no interaction was observed between the light hours provided and the air conditioning systems (P> 0, 05) for daily ration consumption, daily weight gain and feed conversion. In the CRES I phasesthere was no significant difference (P> 0.05) in the light hours provided nor in the air conditioning systems on the analyzed variables. In the CRES II phase there was a significant difference (P <0.05) for daily ration consumption in both light hours and in air conditioning systems. In the baits with forced ventilation (BV) the consumption was greater with the supply of 12 and 18 hours of light. In the bays with evaporative adiabatic cooling (BR), the feed intake was lower (P <0.05) as the light hours provided increased. In the bays with natural light (12 hours) feed consumption was higher in BV, followed by BR, being worse in the unventilated bay (BS) and there was no significant impact on weight gain and feed conversion. When evaluating feed conversion, a significant difference (P <0.05) was observed for light hours and for air conditioning systems. Regardless of the air conditioning systems, feed conversion of the animals worsened as the supply of artificial light increased. Taking into account the systems of climatization it was observed that only in the BR there was worsening in the feed conversion when 12 and 18 hours of light were provided. In the TERM phase the light hours did not influence any of the studied variables. The air conditioning systems did not influence (P> 0.05) the feed conversion rate of finishing pigs. However, the climatization systems influenced (P <0.05) the varying feed intake and daily weight gain. In the bays without air conditioning the feed consumption was lower. In BR the feed intake was higher than that observed in the bays with BV and BS. It was concluded that the climatic systems adopted and the light programs provided did not improve the performance of semen-reared pigs.