Huber R.C.,University of Porto |
Huber R.C.,Danish Center for Bioethics and Risk Assessment |
Huber R.C.,Copenhagen University |
Remuge L.,University of Porto |
And 9 more authors.
Transgenic Research | Year: 2012
Since large animal transgenesis has been successfully attempted for the first time about 25 years ago, the technology has been applied in various lines of transgenic pigs. Nevertheless one of the concerns with the technology-animal welfare-has not been approached through systematic assessment and statements regarding the welfare of transgenic pigs have been based on anecdotal observations during early stages of transgenic programs. The main aim of the present study was therefore to perform an extensive welfare assessment comparing heterozygous transgenic animals expressing GFP with wildtype animals along various stages of post natal development. The protocol used covered reproductory performance and behaviour in GFP and wildtype sows and general health and development, social behaviour, exploratory behaviour and emotionality in GFP and wildtype littermates from birth until an age of roughly 4 months. The absence of significant differences between GFP and wildtype animals in the parameters observed suggests that the transgenic animals in question are unlikely to suffer from deleterious effects of transgene expression on their welfare and thus support existing anecdotal observations of pigs expressing GFP as healthy. Although the results are not surprising in the light of previous experience, they give a more solid fundament to the evaluation of GFP expression as being relatively non-invasive in pigs. The present study may furthermore serve as starting point for researchers aiming at a systematic characterization of welfare relevant effects in the line of transgenic pigs they are working with. © 2011 Springer Science+Business Media B.V.
Collins S.,Roslin Institute |
Forkman B.,Copenhagen University |
Kristensen H.H.,Copenhagen University |
Sandoe P.,Danish Center for Bioethics and Risk Assessment |
Hocking P.M.,Roslin Institute
Applied Animal Behaviour Science | Year: 2011
Behaviour in poultry is predominately visually mediated and vision is important to the welfare of poultry. The relationship between vision, behaviour and welfare has primarily been investigated in relation to artificial lighting. Genetically blind chickens provide an alternative experimental paradigm for further investigating the importance of sight. The primary aim of the study was to investigate the importance of vision in the development and maintenance of behaviour in poultry by comparing the behaviour of 20 genetically blind chicks with that of 20 normally sighted chicks. Behaviour was assessed in a social isolation test post hatch and at 28-30 days old, and in the chicks' 8 home pens (4 blind; 4 sighted) at 42 days old. All birds were weighed at 0, 14, 28 and 42 days old. Analysis of home pen behaviour indicated that, compared to normally sighted chicks, blind chicks displayed increased preening and sitting behaviour, but reduced environmental pecking, behavioural synchrony and group aggregation. Blind chicks also exhibited abnormal behaviours - namely air pecking, star gazing, circle walking. Blind chicks weighed less than sighted chicks at 14, 28 and 42 days of age and appeared to be less stressed by social isolation compared to sighted chicks. It was concluded that blind chicks, as expected, have difficulty expressing behaviours that are normally visually mediated, and that their welfare is likely to be compromised as a result. © 2011 Elsevier B.V.