Effect of feeding regime on the performance and blood parameters of male and female broiler chickens

Abstract

The aim of the present study was to evaluate the effect of feeding regime on changes in growth, mortality, carcass composition, and blood parameters of male and female broiler chickens during feed restriction and the realimentation period. In the experiment, males and females were split into three groups: i) ADL, a group fed ad libitum during the entire experiment; ii) R80, a group that received 80% ad libitum; and iii) R65, a group that received 65% ad libitum. Restriction was applied in both groups from 7 to 14 days old. Daily weight gain (DWG) was reduced significantly in males to 35% in R80 and 39% in R65, and in females to 40% in R80 and 45% in R65. Insignificant compensatory growth occurred in the last week of the growing period. Feed restriction reduced mortality, with a higher mortality reduction in the R65 groups. There was no effect of feed restriction on dressing percentage or thigh yield. However, breast yield was lower and abdominal fat yield was higher in restricted birds. There was a minor effect of feeding regime on blood biochemical and haematological measurements. Males showed significantly higher compensatory growth, feed intake, mortality and thigh yield than females, but dressing percentage and abdominal fat levels were significantly higher in females. Blood total protein and urea concentration were affected by the interaction between sex, group and age.

The effect of feed restriction and housing system on performance, organ proportion and microbiota

“…In addition, pasture access did not have a beneficial effect on the FCR, according to Ponte et al (2008). Feed restriction led to a reduction in mortality, which was only 22% in group 2 and 11% in group 3 in the free-range group compared to that in the AL group; these findings are consistent with those of Mohammadalipour et al (2017), Tumova and Chodova (2018) and Tumova et al (2019). The decreased mortality of restricted chickens is due to a decreased incidence of sudden death syndrome and ascites (Lippens et al 2000;Mohammadalipour et al 2017;Tumova et al 2019) and leg problems (Lippens et al 2000).…”

“…Like those in the gizzard group, the liver proportion in the restricted group increased (P = 0.05), and neither of the restricted groups significantly differed. Tumova et al (2019) observed a greater liver proportion and postulated that this increase is related to greater functional activity and glycogen storage and therefore to increased body fat deposition (Tumova et al 2019).…”

The effect of intermittent feeding and cold water on performance and carcass traits of broilers reared under daily heat stress

“…When the temperature of consumed water is lower than body temperature, which helps to keep the metabolic temperature and increases appetite for water and feed [14]. Cold water intake increases the slaughter weight and average weekly gain [12][13][14][15][16][17][18][19][20][21]. However, in our study, no significant difference was found between slaughtering weights of broilers consumed normal and cold water.…”

“…Actual deaths were within acceptable limits (between 0-1.7%) and evaluated as normal. It was found that intermittent feed and cold water applications did not affect the mortality rate [12][13][14][15][16][17][18][19][20][21][22][23][24].…”

“…Sudden temperature changes may occur in summer months, especially in non-environmentally controlled houses. During these periods, also depending on the relative humidity, it is not possible to cool by using air velocity, and high mortality rates may occur and decrease the overall performance [ 15 ]. The adverse effects of temperature increase on broiler chickens are more pronounced in the second half of the production period (4 to 6 wk), when growth rate and live weight gain are high.…”