Hatching broilers in stables rather than in hatcheries increases animal welfare
A new study at Department of Animal Science shows that hatching broilers on-farm rather than in hatcheries results in a number of benefits: The chicks rest more, take up more feed, weigh more and have a lower mortality.
Traditionally, broilers hatch in a hatchery. It happens during a period of 24–48 hours after which the chicks must go through the procedures in the hatchery as well as transport before being housed in the barn. Some of the procedures are sorting, vaccination and packing followed by transport, unloading and placement in a new environment. Based on previous studies, these procedures are considered significant stress factors in the chicks’ early life.
Hatching on-farm is an alternative to the traditional hatching in a hatchery. Here, the brooded eggs are placed in the barn three days before hatching so that the actual phase of hatching takes place in the stable. Hence, more procedures at the hatchery and transport of day-old chicks are avoided. Furthermore, the chicks have access to feed and water immediately after hatching. But does it make any difference to the chicks’ welfare whether they hatch on-farm or in the hatchery?
Researchers at Aarhus University have examined this question more closely. “We have conducted a study with slow-growing organic broilers hatched either on-farm or at the hatchery. During the study, we have had examined different welfare indicators within the chicks’ biological function, affective states and their possibility of a natural life,” says Project manager and Senior researcher Anja Brinch Riber, Department of Animal Science, Aarhus University.
Study of hatching on-farm and at the hatchery
The study included six flocks per treatment, each consisting of approx. 3600 non-sex-sorted Hubbard JA57 ColorYield broilers. Chicks from the two treatments (meaning chicks hatched either on-farm or at the hatchery) were placed in opposite sections in the same barn.
The hatchery chicks arrived to the barn after a one-hour transport as day-old chicks. Hence, the hatchery chicks arrived to the barn between 5 and 25 hours after hatching. The on-farm chicks were delivered as fertilized brooded eggs three days before arrival of the hatchery chicks. The parents and conditions during storage and brooding were identical for the two treatments.
Positive effects of hatching on-farm
In the study, the researchers found positive effects of a number of welfare indicators for the chicks hatched on-farm compared to those hatched in the hatchery. In the chicks’ early age, the researchers found increased resting behaviour, feeding behaviour and body weight as well as reduced fear of human.
“Furthermore, applicable to the entire growth period, we found a lower mortality and a tendency to a lower level of general fear. Finally, the study indicated that hatchery chicks had been exposed to dehydration during the procedures in the hatchery and the following transport as they partly drank more often afterwards and partly lost weight during transport,” explains Anja Brinch Riber.
The results also showed that the hatchery rate in the on-farm chicks was either higher than or the same as the hatchery chicks, depending on the method of calculation. None of the clinical welfare indicators (gait score, footpad lesions) or production parameters collected at slaughter differed between on-farm chicks and hatchery chicks. However, there was a tendency for more breast blisters in the hatchery male chicks than in the on-farm male chicks.
Hatching on-farm is a valid concept
The researchers conclude that hatching broilers on-farm increases animal welfare and is a valid concept. According to Anja Brinch Riber, the positive effects for the on-farm chicks are especially remarkable as they were obtained even though the study partly included handling in terms of vaccination of on-farm chicks (which is not normal procedure for the typical hybrids (faster growing) hatched on-farm). Partly, the period without water and feed in the hatchery chicks’ early life was relatively short (few hours), which in practice under Danish conditions can last up to 48 hours.
“However, we still have only limited knowledge about hatching on-farm, and many factors may play part. For example, a number of different types of systems exist for hatching on-farm. Therefore, we need more knowledge in this area—especially according to the effect on fearfulness and foot pad dermatitis as well as on how the chick quality affects animal welfare,” concludes Anja Brinch Riber.
Facts about the project
The reply has been conducted as part of the “Framework agreement on research-based public sector consultancy between the Ministry of Environment and Food of Denmark and Aarhus University” under ID 19-H2-09-01 in “Service agreement for animal production 2019–2022.”
Department of Animal Science, Aarhus University.
Senior researcher Anja Brinch Riber, Department of Animal Science, Aarhus University