Effect of dietary energy and stocking density on the performance and sensible heat loss of broilers reared under tropical winter conditions

Abstract

The objective of the present study was to evaluate the effects of different dietary energy levels and stocking densities on the thermoregulating parameters, live performance, and carcass traits of broilers reared under tropical winter conditions at different times of the day. In total, 1,312 one-d-old male broilers were used. Birds were allotted to three different stocking densities (10, 14 or 18 birds/ m 2) and two dietary energy levels (2900 or 3200 kcal ME/kg). The following parameters were evaluated:radiant heat load (RHL), rectal temperature (RT), feed intake (FI), weight gain (WG), feed conversion ratio (FCR), livability (L), production of live weight per area (WA), and carcass yield. Stocking density did not affect sensible heat loss (SRL) or rectal temperature (RT); however, as expected, sensible heat loss (SRL) and RT were influenced by time of the day, with higher values in the morning and in the afternoon, respectively. There was no effect of treatment (p>0.05) on carcass or parts yield. Feed intake was reduced in 3%, whereas weight gain and feed conversion ratio improved in 8 and 10%, respectively, as dietary energy level increased. On the other hand, stocking density did not influence live performance or carcass traits. Based on the present results, it is concluded that sensible heat loss depends on dietary energy levels and particularly on time of the day. Therefore, environmental house management is suggested during tropical winters in order to reduce differences between broiler skin and environmental temperatures in the morning and in the afternoon.

Use of emulsifier and lipase in feeds for broiler chickens

“…Considering the integral period evaluated (37 days), similar to the present experiment, Infante-Rodríguez et al (2016) verified an improvement in the FC of birds fed with higher energy rations. In agreement, Nogueira et al (2013) observed an increase in weight gain and an improvement in feed conversion by birds in response to increased feed energy levels. In turn, Ferreira et al (2015) reported a worse feed conversion rate of broiler chickens at 42 days of age in response to reduced feed metabolisable energy.…”

Effects of stocking density, energy and protein content on performance of broiler chickens raised during late wet season

“…As expected, there was an increase in meat production per area (kg/m 2 ) as a function of SD. This was in agreement with the other authors (Tong et al, 2012;Nogueira et al, 2013). The feed cost per live weight was affected (p<0.05) by SD, with the result following the trend of FLW and WG.…”

“…It is commonly agreed that greater performance in chicks can be achieved if essential amino acids (EAA) in low crude protein diet were equivalent to those needed in the recommended protein diet (Ciftci and Ceylon, 2004;Abdel -Maksoud et al, 2010). Increasing dietary metabolizable energy (ME) significantly increases the body weight gain (Zaman et al, 2008), reduces feed intake and improves feed conversion (Nogueira et al, 2013). Kamran et al (2008a) observed that the reduction in dietary crude protein (CP) and metabolizable energy (ME) content leads to a linear increase in feed intake while weight gain and feed conversion ratio (FCR) are adversely affected.…”

Lighting, density, and dietary strategies to improve poultry behavior, health, and production

“…Broiler chickens reared at high SD (more than 15 bird/m 2 ) significantly reduce the carcass quality, especially thigh, breast yield, and lower breast fillet (Abo Ghanima et al 2020). On the other hand, contradictory studies reported that broiler chickens reared at different SD did not exhibit any significant difference in growth parameters and carcass traits (Nogueira et al 2013;Kryeziu et al 2018;Obeidat et al 2019). In agreement, Avian 48 and Ross 308 broilers, when reared at 40 and 30 kg body weight/m 2 , did not show any difference in growth performance (Ligaraba et al 2016;Palizdar et al 2017).…”