Effects of the level and duration of feeding restriction on carcass components of broilers

Abstract

Abstract. The effects of the restriction of the advised daily feed intake (ADFI) during 1 or 2 weeks on broiler body weight (BW) and carcass composition were studied. A total of 150 1-day-old male broilers (Ross-308) were randomly allotted to a control and four experimental treatments with three replicates per treatment. Broilers were subjected to a feeding restriction equal to 75 and 50 % of ADFI, either for a 7-or a 14-day period, between the 7th and 14th and 7th and 21th day of age, respectively. The BW and carcass composition were determined on day 42. From the findings, neither of the two levels of restriction nor the two time intervals had significant effects (P > 0.05) on the BW or breast and leg weight and proportion, liver and most of the body components. However, the feeding treatments show a tendency (P = 0.078) to influence the BW, with birds fed 75 % of ADFI for 14 day being heavier than the control group. For eviscerated carcass weight, an effect (P = 0.002) was observed, with birds fed 75 % of ADFI for 14 day having heavier carcasses (P < 0.05) than those in control group. The abdominal fat, both with regard to weight and proportion, was slightly influenced by dietary treatments (P > 0.05). From our results, it can be concluded that the applied feeding restrictions have a neutral or slightly beneficial effect on broiler growth traits and carcass composition.

Response of slow-growing chickens to feed restriction and effects on growth performance, blood constituents and immune markers

“…Survival rate was similar among the experimental groups, showing that FR had no harmful effect and correlate to the findings of other experiments (1,5,20) . However, published results indicated that FR increased survival rate due to less sudden death, ascites and skeletal disorders (24,25) .…”

“…In accordance with the current results, immune response against NDV and IBD at 30 th d of age was found to be lower in the FR group than the control group (34) . In addition, FR at 75 and 50 % of daily feed intake during 7-14 or 7-21 d of age did not affect absolute and relative weight of spleen and thymus, but groups on FR at 75 and 50 % for 7 d significantly increased Fabricius bursa compared to their counterparts groups (20) . Similarly, nutritional status had a crucial role in immunity and under-nutrition can negatively affect immune function (29,31) .…”

“…The published results indicated that most weight loss during early FR in chickens could be compensated by 20-25 d of the (19) . Moreover, FR at 75 % or 50 % for 7 and 14 d period, respectively did not significantly influence the final body weight of broilers at 42 d of age (20) . These contradictory results about the effect of FR on the growth could be due to the duration and intensity of FR and/or strain of chickens.…”

“…FR significantly increased plasma albumin (nonspecific immune protein) by 5.3 % compared to the control group, but decreased plasma cholesterol by 3.2 %. Serum glucose (P<0.05) and triglyceride (P<0.001) levels decreased at 41 d of age in broilers fed ad libitum compared to those restricted for 4 h per day from 7 to 21 d and fed ad libitum thereafter (20) . FR at 12.5 and 25 % of the predicted requirement did not significantly influence Hgb, PCV, serum glucose, total protein, globulin, albumin/globulin ratio goats (40) , but decreased serum albumin and urea and improved digestibility of DM, OM, CP, EE and ADF and decreased excretion of N and P. Hepatic leakage (AST and ALT enzymes), muscle catabolism (creatinine) and welfare of chickens (cortisone) at 14 d (end of restriction period) and 35 d of age (end of realimentation period) were not affected by FR regimen.…”

Impact of restricting feed and probiotic supplementation on growth performance, mortality and carcass traits of meat‐type quails

“…Feed restriction is used to retard growth performance of fast growing birds, in particular, in alternative systems of production, which require long growth phases (Govaerts et al, 2000;Jahanpour et al, 2015;Nielsen, Litherland, & Noddegaard, 2003;Soltanmoradi et al, 2014). Nutritionists and researchers have reported that in broilers, physical feed restriction for a short time at an early age decreases abdominal fat, improved growth, and feed efficiency; furthermore, the performance of birds in restricted and unrestricted groups is similar at marketing age (Farghly, Abd El-Hack, Alagawany, Saadeldin, & Swelum, 2018a;Farghly Alagawany & Abd El-Hack, 2018b;Naji, Al-Ani, Manati, & Mukhlis, 2003).…”