Spedgrisens miljøkrav og bruk av spedgrishjørnet

Around 15% of all liveborn piglets die during the lactation period, and this poses a major economical and welfare challenge for the pig production. It has been hypothesized that an increased use of the creep area early after birth will reduce piglet mortality as it provides the piglets with heat and protection from crushing. The aim of this thesis was to investigate environmental requirements and preferences in newborn piglets, and to use this information in an attempt to design a more attractive piglet creep area. Furthermore, we wanted to test the hypothesis that a more attractive creep area would increase the use of the creep area, and reduce piglet mortality. The results showed that piglets were increasingly capable of using thermoregulatory behaviours like posture changes and to a lesser extent, degree of huddling, in order to adapt to changes in the thermal environment, but these strategies were not fine tuned at birth. The thermoregulatory behaviors affected the space occupied by a resting litter, and the creep area must be 1.26 m² in order to accommodate 14 piglets at three weeks of age. In the 60 minute preference test, the piglets preferred to rest in 42 ºC, and in a thick layer of sawdust. Piglets in crates spent more time in the creep area compared to piglets in pens. However, the piglets still chose to rest near the sow when a creep area large enough for the whole litter, containing high infrared temperatures and a thick layer of sawdust was presented in the farrowing pen. The findings from this thesis indicate that piglets are able to assess and adjust to their thermal environment and that they have clear preferences for high infrared temperatures. However, our results also show that quality of the creep area does not increase time spent in the creep area when the sow is present, and more importantly; increased time spent in the creep area does not reduce piglet mortality.Rundt 15 % av alle levendefødte gris dør før avvenning, og dette er en stor utfordring for svinenæringen, både etisk og økonomisk. Man tenker seg at dersom spedgrisen bruker det varme spedgrishjørnet i bingen i en større grad tidlig etter fødsel, kan flere overleve grunnet et lavere varmetap og mer beskyttelse fra å bli ligget på av purka. Målet med denne avhandlingen var å undersøke spedgrisens miljøkrav og preferanser, og ved hjelp av denne kunnskapen utvikle et mer attraktivt spedgrishjørne. Vi ønsket også å undersøke om et mer attraktivt spedgrishjørne kan øke bruken av hjørnet tidlig etter fødsel, og om økt bruk kan redusere spedgristapet. Resultatene viste at spedgris er i stand til å tilpasse seg det termiske miljøet ved å endre sin individuelle liggepositur og, i en mindre grad, nærhet til kullsøsken, og at disse strategiene blir bedre utviklet med alder. Siden temperaturen påvirker spedgrisenes liggemønster, påvirket også temperaturen hvor stor plass et kull med spedgris opptok, og et spedgrishjørne med plass til 14 smågris ved tre uker bør være minimum 1.26 m² for at hele kullet skal få ligge samtidig. I preferansetesten foretrakk spedgrisene 42 ºC, og et tykt lag med sagflis fremfor andre temperaturer og liggeunderlag, men når disse to stimuliene ble kombinert i et spedgrishjørne med plass til alle, valgte de fortsatt å ligge hos purka. Spedgris i fikseringsbinger tilbrakte mer tid i hjørnet enn spedgris i løse binger. Resultatene fra denne avhandlingen viser dermed at spedgris er i stand til å vurdere, og tilpasse seg sitt termiske miljø, og at de har en klar preferanse for høye temperaturer og sagflis. Samtidig fant vi at selv om vi tilbyr spedgrisen et tilsynelatende attraktivt hjørne basert på disse preferansene, fortrekker de fortsatt å ligge hos purka de første dagene etter fødsel. Og kanskje ennå viktigere; vi fant at økt tid brukt i spedgrishjørnet ikke hadde noen sammenheng med spedgrisdødeligheten.Norges Forskningsrå

Developing a novel welfare assessment tool for loose-housed laying hens – the Aviary Transect method

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Experimental factors affecting the within- and between-individual variation of plantar foot surface temperatures in turkeys (Meleagris gallopovo) recorded with infrared thermography

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Description of Light Environment in Broiler Breeder Houses with Different Light Sources—And How It Differs from Natural Forest Light

Light is a key factor in poultry production; however, there is still a lack of knowledge as to describing the light quality, how to measure the light environment as perceived by birds, and how artificial light compares with the light in the natural forest habitats of their wild ancestors. The aim of this study was to describe the light environment in broiler breeder houses with three different light sources, using two different methods of light assessment. We also aimed to compare an artificial light environment with the light in a range of relevant natural forest habitats. A total of 9 commercial broiler breeder houses with one of three different light sources—Lumilux 830 CFL (n = 3), Biolux 965 CFL (n = 3) or LED Evolys with UVA (n = 3) were visited. Assessments of the light environment in the breeder houses were conducted using both a spectrometer and the environmental light field (ELF) method. ELF measurements from three forest types in south India (Kerala) were also included. We found that most aspects of the light environment were similar between the nine breeder houses and were not dependent on the type of light sources. The only clear difference related to the light source was the spectral balance, wherein 830 CFL had the most red-dominated light, 965 CFL had the most blue-dominated light and Evolys was intermediate but with more UV than the latter two. Plumage color had minimal effect on the light environment. Both the spectrometer and the ELF method provided valuable information. The spectrometer gave detailed values about certain aspects of the light environment, while the ELF described the light more in line with human and avian visual perception. We also found that the light environment in the investigated broiler breeder houses differs dramatically in all measured aspects from the natural light habitats of wild junglefowl, suggesting improvement possibilities in artificial lighting systems

Rewarding memories? Behaviour of broiler chickens towards peat in flocks with and without previous exposure to peat

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Association between animal-based measures at 11 weeks and slaughter data at 20 weeks in turkey toms (Meleagris gallopavo)

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Nest building and posture changes and activity budget of gilts housed in pens and crates

AbstractThe aim of the present work was to study nest building, posture changes and the overall activity budget of gilts in pens vs. crates. Twenty-three HB gilts (high piglet survival day 5) and 21 LB gilts (low piglet survival day 5) were video recorded from day 110 in pregnancy to four days after farrowing in either a farrowing pen or farrowing crate. The gilts were provided with 2kg of chopped straw daily from day 113 of pregnancy until farrowing in both environments. Nest building and other activity measures of the sows were analysed using continuous sampling the last 12h before the first piglet was born until 8h after the birth of the first piglet. There was no significant effect of the sows breeding value on any of the sow behaviours. Sows housed in pens spent significantly more time nest building than crated sows from 4 to 12h prepartum (P<0.05). Crated sows spent more time sitting (P<0.01), chewed more frequently on pen fittings (P<0.001) and showed a higher frequency of quick flops when entering a resting position after farrowing (P<0.05), but had a lower number of posture changes (P<0.05) after farrowing.In conclusion, provision of a similar amount of straw does not compensate for the lack of space in the crate compared to the pens. Sows in pens spent more time nest building from 4 to 12h post partum compared to crated sows, and crated sows showed more behaviours related to frustration and restlessness

Associations between on-farm welfare measures and slaughterhouse data in commercial flocks of turkey hens (Meleagris gallopavo)

There is a growing demand for documentation of animal welfare in meat production industry. Research on turkey welfare has mainly focused on toms at the end of production cycle, and information on the relationship between on-farm welfare and slaughterhouse recordings for turkey hens is currently lacking. The aim of this study was to investigate the relationship between routinely collected slaughterhouse data from turkey hens and their on-farm welfare measured by transect walks, to identify potential retrospective welfare indicators. The study was conducted between November 2017 and March 2018 in 20 commercial turkey flocks in Norway. On-farm welfare was evaluated using the transect walk method when the turkey hens were 11 wk old, recording the number of birds that were immobile, lame, small, featherless, dirty, sick, terminal, or dead and had visible head, tail, or wing wounds. Slaughterhouse data was provided for each flock. Univariate and multivariate linear regression models were used to investigate the associations between the variables. The results showed significant associations between several measures on farm and at slaughter. Flocks with more lameness on farm had more birds rejected at the slaughterhouse owing to leg and joint issues (P = 0.03, r = 1.01). Featherlessness and dirtiness on farm were positively associated with airsacculitis (P = 0.005; r = 0.42 and P = 0.0008; r = 0.57, respectively). The results suggest that slaughterhouse registrations may provide both practical and feasible retrospective information on the welfare of turkey hens that potentially could be implemented in future welfare assessment schemes. Further studies are needed to investigate the causal factors behind the identified relationships

On-farm broiler chicken welfare assessment using transect sampling reflects environmental inputs and production outcomes

To evaluate the utility of transect sampling for assessing animal welfare in large chicken flocks, we quantified relationships between environmental inputs, welfare problems detected using transect sampling, and production outcomes. We hypothesised that environmental inputs including environmental complexity (i.e. number of environmental enrichment types provided), space allowance, underfloor heating (presence or absence), and photoperiod regimen (18 h continuous vs 16 h intermittent) would correspond to variations in welfare assessment findings, which would predict production outcomes. We conducted on-farm welfare assessment of Norwegian broiler flocks at approximately 28 days of age. We sampled four transects (rows between feeder and drinker lines) per flock to determine litter quality and the proportions of chickens with compromised welfare as indicated by visual signs of walking difficulties, illness, skin wounds and small bird size. Production outcome measures included mortality, reasons for carcass rejection at slaughter, footpad dermatitis, growth rate, feed conversion and an integrated production index. Greater environmental complexity was associated with a reduction in skin wounds and total welfare problems on the farm, lower mortality, fewer rejections due to wounds and underweight birds, and fewer rejections overall. Higher space allowances within levels of environmental complexity were associated with fewer walking difficulties and welfare problems overall, a reduction in rejections due to wounds, and a higher growth rate and production index. Underfloor heating was associated with a reduction in rejections due to leg deformity, and intermittent light was associated with lower illness and skin wound rates on the farm, and lower mortality. Furthermore, fewer welfare problems and better litter quality on the farm were associated with fewer carcass rejections at slaughter. Thus, data from transect sampling varied with environmental inputs and production outcomes, supporting the validity of transect sampling for practical, animal-based on-farm welfare assessment.publishedVersio