Graded atmospheric oxygen level effects on performance and ascites incidence in broilers

Abstract

The effects of graded atmospheric O2 concentration (12, 14, 16, 18, and 20.6%) on chick performance and propensity to develop ascites were investigated using commercial male broilers. Chicks were housed in calorimetry chambers for 2 wk with incoming air diluted with N to provide the desired O2 concentration at thermoneutral (TN) ambient temperature. Day 14 body weight, weight gain, feed consumption, and gain-to-feed ratio increased (P < 0.01) as O2 concentration incrementally rose from 12 to 20.6%. Body weight was 138 g for the lowest atmospheric O2 level compared to 371 g for 20.6% O2. The greatest treatment difference occurred between the 12 and 14% O2 concentrations. Growth depression appeared related to feed consumption. Ascites heart ratio (AHR), ascites score (AS), right ventricular mass (RVM), and hematocrit (HCT) all increased (P < 0.01) as O2 concentration decreased. Blood HCT appeared to be a more sensitive indicator of physiological change attributable to atmospheric O2 than AHR, AS, or RVM. The data reported herein suggests that 19.6% atmospheric O2 is the minimal allowable level for housing birds within a relatively stress-free, TN environment to avoid cardiac and HCT changes related to ascites.

Effect of oxygen supplementation in a hatchery at high altitude and growth performance of broilers reared at low altitude

“…Some researchers have suggested that extra O 2 supplementation during high-altitude incubation improves body weight, feed consumption and FCR (Beker et al, 2003;Quintana et al, 2006;Çelen et al, 2009) in 42-day-old broilers reared at low altitude. However, in the present study, at the end of the growing period, feed consumption and FCR were lower in the LA-NOX group than the HA ones.…”

“…Growth increases the need for O 2 consumption (Beker et al, 2003), and rapidly growing broiler chickens need O 2 for their high metabolic requirements (Julian et al, 1989). As the O 2 level decreases with altitude, exposure to chronic hypoxia increases mortality during incubation and decreases growth as a result of adaptation (Julian, 2000;Villamor et al, 2004).…”

“…Oxygen concentration plays a major role in the onset of ascites; reduction in atmospheric O 2 concentration effectively induces ascites. It is therefore important to keep the O 2 concentration above 19.6% to minimize ascites-related anomalies and maximize performance (Beker et al, 2003). Fast-growing chicken breeds are more likely to suffer from ascites because of their rapid growth and high metabolic rate, both of which require more O 2 (Acar et al, 1995).…”

Effects of oxygen supplementation during the last stage of incubation on broiler performance, ascites susceptibility and some physiological traits

“…Growth, particularly which of lean tissue, increases the need for O 2 consumption [4]. Maxwell et al [22] and Witzel [18] concluded that BW at 8 weeks of age was correlated with embryonic O 2 consumption on day 14-19 of incubation.…”

“…Beker et al [3] demonstrated an inverse relationship between oxygen consumption and ascites incidence (R 2 = 0.96). Beker et al [4] found that final BW, BW gain, feed consumption and gain to feed ratio increased quadratically as the partial pressure of O 2 rose from 12% to 20.6%, while ascites heart ratio, ascites score, right ventricular mass and hematocrit increased as partial pressure of O 2 decreased. Additionally, Vander Hel et al [32] compared 1 d old chicks exposed to 15% O 2 with control birds exposed to 20.9% O 2 .…”