UK survey of broiler ascites and sudden death syndromes in 1993

Abstract

1. The mean incidence of deaths from ascites in the UK in 1993 was 1.4% (0.7% in 1991 and 0.9% in 1992) and 0.8% from sudden death syndrome (SDS). In total, the economic loss to the UK Broiler Industry in 1993 as a result of these 2 conditions was 24 Pounds M. 2. Clear geographical differences emerged in the occurrence of ascites, with, not only the lowest incidences being observed in Northern Ireland, but also the peak of the mortality from ascites occurring much later in the rearing cycle than in other regions on the mainland. 3. In all regions the incidence of SDS was lower than that of ascites but the reason for this disparity remains to be established. 4. Some of the variables associated with the road transportation of day-old chicks from the hatchery to the farm appeared to influence the incidence of ascites. These included distance or time travelled, stocking density, internal lorry temperature and the length of time the lorry was heated before transport as well as the time the shed was heated before chick arrival. Temperature was also an important factor during growth (brooding and finishing). 5. Negative pressure-powered ventilation was preferred in most organisations but more ascites was seen with positive pressure ventilation. However, the lowest incidence of ascites occurred with natural ventilation. There was more ascites relative to shed orientation when the wind direction was from the west compared to the east. 6. This survey identifies the extent of the problem of broiler ascites in the UK and also highlights the importance of good management control of day-old chicks, not only following placement, but even before their arrival on the farm.

Use of geostatistics on broiler production for evaluation of different minimum ventilation systems during brooding phase

“…The ammonia concentration was 57.8 and 35.93 ppm in Dark House and Blue House I, respectively (Figure 6). These values were above the recommended limit of 20 ppm, which can be harmful to the birds' welfare (Manning et al, 2007). This variable distribution was homogeneous in Blue House I, with an average variability for the other houses.…”

“…The air renewal influences the birds behavior positively through the maximum wind speed of 0.59 m s -1 which may provide the maintenance of NH 3 and CO 2 concentrations to lower limits than those recommended by Manning et al (2007). Through Figures 6 and 7 it can be noticed that although the gas concentration was high in some areas, these values only occurred in small areas near the exhaust fans in Blue House I.…”

“…Metabolic syndromes and respiratory diseases are related to low oxygen concentration in the brooding area due to improper air exchanges (Maxwell & Robertson 1998). High gas concentration in broiler houses has been reported by several researchers (Redwine et al, 2002;Miles et al, 2004;Miles et al, 2006;Miles et al, 2008).…”

Protein levels and environmental temperature effects on carcass characteristics, performance, and nitrogen excretion of broiler chickens from 7 to 21 days of age

“…Therefore, higher temperatures than those may induce hyperthermia and dehydration, resulting in lower feed intake and delayed growth (Mickelberry et al, 1966). On the other hand, temperatures much lower than thermoneutral temperatures might result in hypothermia and induce pulmonary hypertension syndrome (ascites) (Maxwell & Robertson, 1998).…”

Cortisol response to stress is associated with myocardial remodeling in salmonid fishes

“…Severe stress is clearly associated with a poor prognosis in individuals with established cardiac pathology and disease, including in humans (Engel, 1971;Meerson, 1994;Maxwell and Robertson, 1998;Brocklebank and Raverty, 2002;Poppe et al, 2007). Still, the mechanism linking stress responsiveness to the development of cardiac disease is poorly understood in fish.…”