Effect of dietary probiotic and high stocking density on the performance, carcass yield, gut microflora, and stress indicators of broilers

Abstract

A study was carried out to evaluate the effect of dietary probiotic supplementation and stocking density on the performance, relative carcass yield, gut microflora, and stress markers of broilers. One-day-old Ross 308 male broiler chickens (n = 480) were allocated to 4 experimental groups for 42 d. Each treatment had 8 replicates of 15 chicks each. Two groups were subjected to a high stocking density (HSD) of 20 birds/m² and the other 2 groups were kept at low stocking density (LSD) of 10 birds/m². A basal diet supplemented with probiotic 1 and 0.5 g/kg of diet (in starter and finisher diets, respectively) was fed to 2 treatments, one with HSD and the other with LSD, thereby making a 2 × 2 factorial arrangement. There was no interaction between stocking density (LSD and HSD) and dietary probiotic (supplemented and unsupplemented) for all the variables. Feed intake and weight gain were significantly low and feed conversion ratio was poor in broilers at HSD. Dietary probiotic significantly enhanced the feed intake and weight gain in starter phase only. Dietary probiotic supplementation had no effect (P > 0.05) on total aerobs, Salmonella sp., and Lactobacilli populations in the intestines of broilers. However, HSD reduced the Lactobacilli population only (P < 0.05). Relative breast yields were significantly higher in broilers reared at LSD than HSD. Thigh meat yield was higher in broilers in HSD group compared to LSD. Dietary probiotic did not affect the relative carcass yield and weight of lymphoid organs. Serum malondialdehyde, corticosterone, nitric oxide, and plasma heterophil:lymphocyte ratio were not affected either by stocking density or dietary probiotic supplementation. In conclusion, HSD negatively affected the performance and intestinal Lactobacilli population of broilers only, whereas probiotic supplementation enhanced the performance of broilers during the starter phase only. Total aerobes, Salmonella, Lactobacilli carcass yield, and stress indicators of broilers were not affected by the dietary supplementation of probiotic under the conditions of the present study.

Effect of dietary l‐carnitine supplementation and energy level on oxidant/antioxidant balance in laying hens subjected to high stocking density

“…Consistent with our results, Thaxton et al (2006) and Chegini, Kiani, and Rokni (2018) observed that NO concentration was increased by the high stocking densities. In contrast with our findings, Cengiz et al (2015) found that the blood NO of broilers was not affected by the stocking density. In contrast with our findings, Cengiz et al (2015) found that the blood NO of broilers was not affected by the stocking density.…”

“…Furthermore, it was reported that environmental stress, including high temperature, causes oxidative stress with increased production of MDA (Halliwell & Gutteridge, 1984). On the contrary, Cengiz et al (2015) reported that the blood MDA of broilers was not affected by the stocking density. These different outcomes could be due to the various stress condition of birds such as severity of stressful condition and type of stress.…”

Response of broiler chickens reared at high density to dietary supplementation with licorice extract and probiotic

“…In this regards, Mountzouris et al () reported that dietary probiotics improved BWG and FCR in broilers by secretion of different digestive enzymes (amylolytic, proteolytic and lipolytic) in the intestines. However, Cengiz et al () showed that there was no interaction between dietary probiotic and stocking density in broilers. Vargas‐Rodr´iguez et al () reported that FI, BWG or FCR were not affected by supplementation of broiler diet with probiotic throughout the growing period.…”

Antioxidant Defence Systems and Oxidative Stress in Poultry Biology: An Update

“…Chick placement [1,[17][18][19][20][21][22] Increased stocking density [23][24][25][26][27][28][29][30][31] Weighing, grading, group formation, catching, transferring to breeder houses [1,18,19] Prolonged egg storage, egg transportation, inadequate egg storage conditions, incorrect incubation regimes [1,18,19] Environmental stressors…”