51 research outputs found

    Factors affecting mechanical (nociceptive) thresholds in piglets

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    AbstractObjectiveTo evaluate the stability and repeatability of measures of mechanical (nociceptive) thresholds in piglets and to examine potentially confounding factors when using a hand held algometer.Study designDescriptive, prospective cohort.AnimalsForty-four piglets from four litters, weighing 4.6 ± 1.0 kg (mean ± SD) at 2 weeks of age.MethodsMechanical thresholds were measured twice on each of 2 days during the first and second week of life. Data were analyzed using a repeated measures design to test the effects of behavior prior to testing, sex, week, day within week, and repetition within day. The effect of body weight and the interaction between piglet weight and behaviour were also tested. Piglet was entered into the model as a random effect as an additional test of repeatability. The effect of repeated testing was used to test the stability of measures. Pearson correlations between repeated measures were used to test the repeatability of measures. Variance component analysis was used to describe the variability in the data.ResultsVariance component analysis indicated that piglet explained only 17% of the variance in the data. All variables in the model (behaviour prior to testing, sex, week, day within week, repetition within day, body weight, the interaction between body weight and behaviour, piglet identity) except sex had a significant effect (p < 0.04 for all). Correlations between repeated measures increased from the first to the second week.Conclusions and Clinical relevanceRepeatability was acceptable only during the second week of testing and measures changed with repeated testing and increased with increasing piglet weight, indicating that time (age) and animal body weight should be taken into account when measuring mechanical (nociceptive) thresholds in piglets. Mechanical (nociceptive) thresholds can be used both for testing the efficacy of anaesthetics and analgesics, and for assessing hyperalgesia in chronic pain states in research and clinical settings

    The Effect of LPS and Ketoprofen on Cytokines, Brain Monoamines, and Social Behavior in Group-Housed Pigs

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    Poor health is a risk factor for damaging behaviors, but the mechanisms behind this link are unknown. Injection of pigs with lipopolysaccharide (LPS) can be used to model aspects of poor health. Recent studies have shown that LPS-injected pigs perform more tail- and ear-directed behavior compared to saline-injected pigs and suggest that pro-inflammatory cytokines may play a role in these behaviors. The aims of this study were to test the effect of LPS on the social behavior of pigs and the neurotransmitters and modulators in their brains and to test the effect of a nonsteroidal anti-inflammatory drug on the effects of LPS. Fifty-two female pigs (11-12 weeks) were allocated to four treatments comprising two injections: saline-saline (SS), saline-LPS (SL), ketoprofen-saline (KS), and ketoprofen-LPS (KL). Activity was scan-sampled every 5 min for 6 h after the last injection in the pen. Social behavior was observed continuously in 10 x 15-min bouts between 8 a.m. and 5 p.m. 1 day before (baseline) and 1 and 2 days after the injection. Saliva was analyzed for cortisol and plasma for tryptophan and kynurenine. The frontal cortex, hippocampus, hypothalamus, and brain stem were sampled 72 h after the injection and analyzed for cytokines and monoamines. LPS activated the HPA axis and decreased the activity within 6 h after the injection. Ketoprofen lowered the effect of LPS on cortisol release and attenuated the behavioral signs of sickness in challenged pigs. SL pigs manipulated the ears of their pen mates significantly longer than SS pigs 2 days after the injection. LPS had no observed effect on IFN-gamma, TNF-alpha, and IL-18. At 72 h after the injection, plasma tryptophan was depleted in SL pigs, and tryptophan and kynurenine concentrations in the frontal cortex and brain stem of SL pigs were significantly lower compared to those in SS pigs. Dopamine concentrations in the hypothalamus of SL pigs were significantly lower compared to those in SS pigs. Serotonin concentrations in the hypothalamus and noradrenaline concentrations in the hippocampus of SL pigs were significantly lower compared to those in KL pigs. In conclusion, LPS influenced the different neurotransmitters and modulators in the brain that are hypothesized to play an important role in the regulation of mood and behavior.Peer reviewe

    Does Rearing Laying Hens in Aviaries Adversely Affect Long-Term Welfare following Transfer to Furnished Cages?

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    Abstract This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare between aviary and cage reared hens in production, non-beak trimmed white leghorn birds from both rearing backgrounds were filmed at a commercial farm that used furnished cage housing. The videos were taken at 19 and 21 weeks of age, following the birds&apos; transition to the production environment at 16 weeks. Videos were analysed in terms of the performance of aversion-related behaviour in undisturbed birds, comfort behaviour in undisturbed birds, and alert behaviour directed to a novel object in the home cage. A decrease in the performance of the former behaviour and increase in the performance of the latter two behaviours indicates improved welfare. The results showed that aviary reared birds performed more alert behaviour near to the object than did cage reared birds at 19 but not at 21 weeks of age (P = 0.03). Blood glucose concentrations did not differ between the treatments (P.0.10). There was a significant difference in mortality between treatments (P = 0.000), with more death in aviary reared birds (5.52%) compared to cage birds (2.48%). The higher mortality of aviary-reared birds indicates a negative effect of aviary rearing on bird welfare, whereas the higher duration of alert behavior suggests a positive effect of aviary rearing

    A Proposed Role for Pro-Inflammatory Cytokines in Damaging Behavior in Pigs

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    Sickness can change our mood for the worse, leaving us sad, lethargic, grumpy and less socially inclined. This mood change is part of a set of behavioral symptoms called sickness behavior and has features in common with core symptoms of depression. Therefore, the physiological changes induced by immune activation, for example following infection, are in the spotlight for explaining mechanisms behind mental health challenges such as depression. While humans may take a day off and isolate themselves until they feel better, farm animals housed in groups have only limited possibilities for social withdrawal. We suggest that immune activation could be a major factor influencing social interactions in pigs, with outbreaks of damaging behavior such as tail biting as a possible result. The hypothesis presented here is that the effects of several known risk factors for tail biting are mediated by pro-inflammatory cytokines, proteins produced by the immune system, and their effect on neurotransmitter systems. We describe the background for and implications of this hypothesis.Peer reviewe

    Classification of pig calls produced from birth to slaughter according to their emotional valence and context of production

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    Vocal expression of emotions has been observed across species and could provide a non-invasive and reliable means to assess animal emotions. We investigated if pig vocal indicators of emotions revealed in previous studies are valid across call types and contexts, and could potentially be used to develop an automated emotion monitoring tool. We performed an analysis of an extensive and unique dataset of low (LF) and high frequency (HF) calls emitted by pigs across numerous commercial contexts from birth to slaughter (7414 calls from 411 pigs). Our results revealed that the valence attributed to the contexts of production (positive versus negative) affected all investigated parameters in both LF and HF. Similarly, the context category affected all parameters. We then tested two different automated methods for call classification; a neural network revealed much higher classification accuracy compared to a permuted discriminant function analysis (pDFA), both for the valence (neural network: 91.5%; pDFA analysis weighted average across LF and HF (cross-classified): 61.7% with a chance level at 50.5%) and context (neural network: 81.5%; pDFA analysis weighted average across LF and HF (cross-classified): 19.4% with a chance level at 14.3%). These results suggest that an automated recognition system can be developed to monitor pig welfare on-farm.publishedVersio

    Does rearing laying hens in aviaries adversely affect long-term welfare following transfer to furnished cages?

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    This study tests the hypothesis that hens that are reared in aviaries but produce in furnished cages experience poorer welfare in production than hens reared in caged systems. This hypothesis is based on the suggestion that the spatial restriction associated with the transfer from aviaries to cages results in frustration or stress for the aviary reared birds. To assess the difference in welfare between aviary and cage reared hens in production, non-beak trimmed white leghorn birds from both rearing backgrounds were filmed at a commercial farm that used furnished cage housing. The videos were taken at 19 and 21 weeks of age, following the birds' transition to the production environment at 16 weeks. Videos were analysed in terms of the performance of aversion-related behaviour in undisturbed birds, comfort behaviour in undisturbed birds, and alert behaviour directed to a novel object in the home cage. A decrease in the performance of the former behaviour and increase in the performance of the latter two behaviours indicates improved welfare. The results showed that aviary reared birds performed more alert behaviour near to the object than did cage reared birds at 19 but not at 21 weeks of age (P = 0.03). Blood glucose concentrations did not differ between the treatments (P>0.10). There was a significant difference in mortality between treatments (P = 0.000), with more death in aviary reared birds (5.52%) compared to cage birds (2.48%). The higher mortality of aviary-reared birds indicates a negative effect of aviary rearing on bird welfare, whereas the higher duration of alert behavior suggests a positive effect of aviary rearing

    The release of common pheasants and grey partridges for pointing dog training- consequences for biodiversity, animal welfare and health. Scientific Opinion of the Panel on Biodiversity of the Norwegian Scientific Committee for Food and Environment

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    Source at https://vkm.no/.Bakgrunn Siden sent på 1800-tallet har det blitt satt ut et ukjent antall tamme fasaner og rapphøns i norsk natur. Disse fuglene brukes til jakttrening av stående fuglehunder. Import, hold og utsetting av fasaner og rapphøns har i liten grad vært regulert og det er heller ikke utredet hvilke konsekvenser som import, hold og utsetting og jakttrening vil kunne ha for biologisk mangfold, dyrehelse og dyrevelferd. Miljødirektoratet og Mattilsynet har i felleskap bedt VKM om å utarbeide en vitenskapelig vurdering av mulige konsekvenser av utsetting av fasan og rapphøns på biologisk mangfold, dyrehelse og dyrevelferd. VKM ble også bedt om å foreslå eventuelle risikoreduserende tiltak for biologisk mangfold og dyrevelferd. Metoder VKM opprettet en prosjektgruppe med ekspertise innenfor blant annet fugleøkologi, landskapsøkologi, populasjonsbiologi, viltmedisin og dyrevelferd. Gruppen utførte systematiske litteratursøk, undersøkte resultatene fra søkene og supplerte med andre relevante studier der det var nødvendig. I mangel av studier fra norske forhold brukte VKM studier fra andre land som setter ut fasaner og rapphøns (og i noen tilfeller andre arter av fuglevilt) som referanse. VKM undersøkte observasjonsdata for fasaner og rapphøns i Norge for perioden 2000 til 2022. I vurderingen av de ulike aspektene som vil kunne påvirkes av utsettingen, la VKM til grunn en årlig utsetting av noen få tusen fugler i Norge. Høyere antall og tetthet av fugler vil øke sannsynligheten for negative effekter og alvorlighetsgraden av konsekvensene. VKM vurderte effekten som utsatte fasaner og rapphøns har på konkurranse med norske fugler,, krysning med beslektede arter, sykdomsoverføring, effekter på flora (herbivori), og fauna (predasjon). I tillegg ble indirekte effekter gjennom interaksjon med andre arter vurtdert. VKM vurderte også effekt på biologisk mangfold i et 50-års perspektiv. I tillegg diskuterte VKM hvordan fuglenes velferd vil kunne påvirkes av hold, transport, utsetting, og eksponering for jakthunder. VKM lister også opp relevante sykdommer og vurderer den potensielle effekten av disse på dyrehelse under hold, transport og utsetting. For vurdering av aspekter relatert til import og dyrehelse, la VKM til grunn at fuglene importeres fra Sverige. Resultater og konklusjoner VKMs vurderinger viste at utsetting av fasaner og rapphøns i norsk natur medfører risiko for biologisk mangfold, dyrehelse og dyrevelferd. Risiko for økt konkurranse om mat vinterstid med fugler som har lignende økologisk nisje som fasaner og rapphøns, er lav på nasjonal skala og moderat på lokal skala. Det gjelder spesielt gulspurv, Emberiza citronella. Denne arten er klassifisert som sårbar på den nasjonale rødlisten grunnet økende nedgang i bestanden, som igjen er forårsaket av redusert tilgjengelighet av mat om vinteren. Det er videre moderat risiko for predasjon på invertebrater (virvelløse dyr) og negative effekter på flora.The release of common pheasants and grey partridges for pointing dog training- consequences for biodiversity, animal welfare and health. Scientific Opinion of the Panel on Biodiversity of the Norwegian Scientific Committee for Food and EnvironmentpublishedVersio

    Transmission of Stress-Induced Learning Impairment and Associated Brain Gene Expression from Parents to Offspring in Chickens

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    BACKGROUND: Stress influences many aspects of animal behaviour and is a major factor driving populations to adapt to changing living conditions, such as during domestication. Stress can affect offspring through non-genetic mechanisms, but recent research indicates that inherited epigenetic modifications of the genome could possibly also be involved. METHODOLOGY/PRINCIPAL FINDINGS: Red junglefowl (RJF, ancestors of modern chickens) and domesticated White Leghorn (WL) chickens were raised in a stressful environment (unpredictable light-dark rhythm) and control animals in similar pens, but on a 12/12 h light-dark rhythm. WL in both treatments had poorer spatial learning ability than RJF, and in both populations, stress caused a reduced ability to solve a spatial learning task. Offspring of stressed WL, but not RJF, raised without parental contact, had a reduced spatial learning ability compared to offspring of non-stressed animals in a similar test as that used for their parents. Offspring of stressed WL were also more competitive and grew faster than offspring of non-stressed parents. Using a whole-genome cDNA microarray, we found that in WL, the same changes in hypothalamic gene expression profile caused by stress in the parents were also found in the offspring. In offspring of stressed WL, at least 31 genes were up- or down-regulated in the hypothalamus and pituitary compared to offspring of non-stressed parents. CONCLUSIONS/SIGNIFICANCE: Our results suggest that, in WL the gene expression response to stress, as well as some behavioural stress responses, were transmitted across generations. The ability to transmit epigenetic information and behaviour modifications between generations may therefore have been favoured by domestication. The mechanisms involved remain to be investigated; epigenetic modifications could either have been inherited or acquired de novo in the specific egg environment. In both cases, this would offer a novel explanation to rapid evolutionary adaptation of a population

    Early life in a barren environment adversely affects spatialcognition in laying hens (Gallus gallus domesticus)

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    Spatial cognition in vertebrates is adversely affected by a lack of environmental complexity during early life. However, to our knowledge, no previous studies have tested the effect of early exposure to varying degrees of environmental complexity on specific components of spatial cognition in chickens.There are two main rearing systems for laying hens in the EU: aviaries and cages.These two systems differ from one another in environmental complexity. The aim of the present study was to test the hypothesis that rearing in a barren cage environment relative to a complex aviary environment causes long-lasting deficits in the ability to perform spatial tasks. For this purpose, 24 white Dekalb laying hens, half of which had been reared in an aviary system and the other half in a conventional cage system, were tested in a holeboard task. Birds from both treatment groups learnt the task; however, the cage-reared hens required more time to locate rewards and had poorer levels of working memory. The latter finding supports the hypothesis that rearing in a barren environment causes long-term impairment of short-term memory in chickens
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