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Associations of conformation and locomotive characteristics in growing gilts with osteochondrosis at slaughter
Koning, D.B. de; Grevenhof, E.M. van; Laurenssen, B.F.A. ; Hazeleger, W. ; Kemp, B. - \ 2015
Journal of Animal Science 93 (2015)1. - ISSN 0021-8812 - p. 93 - 106.
linear type traits - leg weakness - exterior traits - genetic correlations - epiphyseal growth - pigs - cartilage - sows - lesions - pathogenesis
Osteochondrosis (OC) and abnormalities in conformation and locomotive characteristics (CLC) have been associated with premature culling in sows. Several CLC have been suggested to be associated with OC and might help as an in vivo indicator for and increased risk of having OC. The aim of this study was to investigate associations of OC with CLC assessed at several ages in growing gilts from 2 separate experiments over the effects of dietary restriction (Exp. 1) and floor type (Exp. 2) on OC prevalence. In Exp. 1, gilts (n = 211) were subjectively assessed for CLC at, on average, 4, 9, 11, 16, and 24 wk of age. In Exp. 2, gilts (n = 212) were subjectively assessed for CLC at, on average, 4, 9, 11, 16, and 22 wk of age. Assessment was done on 10 conformation and 2 locomotive characteristics using a 9-point grading scale by 2 observers. At, on average, 27 wk of age in Exp. 1 and 24 wk of age in Exp. 2, gilts were slaughtered and the knee, elbow, and hock joints were macroscopically assessed for OC. The CLC most frequently associated with OC were O shape or X shape of the hind legs, straight or bowed hind legs, and straight or sickled hock. X-shaped hind legs were associated with OC at slaughter in the knee joint at 4, 9, and 24 wk of age and at the animal level (all joints taken together) at 4, 9, and 16 wk of age. Straight or bowed hind legs were associated with OC at slaughter in the knee joint at 4 and 11 wk of age; in the hock joint at 11 wk of age; and at the animal level at 4, 9, 11, and 22 wk of age. Straight or sickled hock was associated with OC at slaughter in the knee joint at 4 wk of age, in the hock joint at 9 and 22 wk of age, and at the animal level at 9 and 22 wk of age. Results show that several CLC assessed at several ages were associated with OC, but consistent associations of a type of CLC in every assessment could not be found. The associations of CLC with OC are, therefore, difficult to be used as an in vivo indicator of increased risk for OC.
The influence of floor type before and after 10 weeks of age on osteochondrosis in growing gilts
Koning, D.B. de; Grevenhof, E.M. van; Laurenssen, B.F.A. ; Weeren, P.R. van; Hazeleger, W. ; Kemp, B. - \ 2014
Journal of Animal Science 92 (2014)8. - ISSN 0021-8812 - p. 3338 - 3347.
different coping characteristics - leg weakness - finishing pigs - growth-rate - genetic-parameters - epiphyseal growth - production traits - stocking density - claw disorders - behavior
Osteochondrosis (OC) is a degenerative joint condition developing in a short time frame in young growing gilts that may cause lameness at an older age, affecting welfare and leading to premature culling of breeding sows. Causes of OC are multifactorial including both genetic and environmental factors. Floor type has been suggested to affect OC prevalence and effects might be age dependent during the rearing period. The aim of this study was to investigate possible age-dependent effects of floor type, conventional concrete partially slatted versus wood shavings as deep bedding, on OC prevalence in gilts (Dutch Large White × Dutch Landrace) at slaughter (24 wk of age; 106.5 [14.7 SD] kg of BW). At weaning (4 wk of age; 6.9 [1.3 SD] kg of BW), 212 gilts were subjected to 1 of 4 flooring regimens. Gilts were either subjected to a conventional floor from weaning until slaughter (CC), wood shavings as bedding from weaning until slaughter (WW), a conventional floor from weaning until 10 wk of age after which gilts were switched to wood shavings as bedding (CW), or wood shavings as bedding from weaning until 10 wk of age after which gilts were switched to a conventional floor (WC). After slaughter the elbow, hock, and knee joints were macroscopically examined for OC and scored on a 5 point scale where 0 indicates no OC and 4 indicates the severest form of OC. There was no significant difference (P > 0.4) between treatments on the overall OC prevalence for any joint assessed or at the animal level (all joints combined). At the animal level, however, gilts had greater odds to have OC scores 3 and 4 in the CW treatment (odds ratios [OR] = 2.3; P = 0.05), WC treatment (OR = 2.6; P = 0.02), and WW treatment (OR = 3.7; P <0.001) compared with gilts in the CC treatment. The results indicate that there are no age-dependent effects of floor types on overall OC prevalence. However, wood shavings as bedding seems to increase the odds for severe OC and might affect animal welfare in the long term.
Wet litter not only induces footpad dermatitis but also reduces overall welfare, technical performance, and carcass yield in broiler chickens
Jong, I.C. de; Gunnink, H. ; Harn, J. van - \ 2014
Journal of Applied Poultry Research 23 (2014)1. - ISSN 1056-6171 - p. 51 - 58.
pad dermatitis - leg weakness - prevalence
This study investigated whether a high level of footpad dermatitis (FPD) in broiler chickens induced by increased litter moisture content is accompanied by negative effects on technical performance, carcass yield, and other welfare aspects. Litter moisture content was increased by systematically spraying water over the litter from 6 d of age onward (lesion-induction treatment). Results were compared with a control group kept on relatively good quality litter and having a very low prevalence of footpad lesions. Litter quality significantly decreased from 7 d of age onward in the pens with the lesion-induction treatment compared with the control pens. At 21 and 36 d of age, significantly more FPD was observed in the lesion-induction groups compared with the control groups. Technical performance of the broilers was negatively affected for the lesion-induction groups from 28 d of age onward; lesion-induction groups had significantly lower BW gain, feed intake, and water intake and significantly higher FCR compared with control groups. As a result of the lower BW gain, carcass weight was less for the lesion-induction group and significantly more rejections for commercial parts were found. The lesion-induction groups also had significantly more hock burns and breast irritations at d 21 and 36, and were dirtier but had fewer thigh scratches at d 35 compared with the control groups. In addition, locomotion was negatively affected among the lesion-induction group, as they had a higher gait score at d 36 compared with the control group. We concluded that increased litter moisture content not only caused severe FPD but also reduced broiler performance and carcass yield and had a negative effect on other welfare aspects.
Potential risk factors associated with contact dermatitis, lameness, negative emotional state, and fear of humans in broiler chicken flocks
Bassler, A. ; Arnould, C. ; Butterworth, A. ; Colin, L. ; Jong, I.C. de; Ferrante, V. ; Ferrari, P. ; Haslam, S.A. ; Wemelsfelder, F. ; Blokhuis, H.J. - \ 2013
Poultry Science 92 (2013)11. - ISSN 0032-5791 - p. 2811 - 2826.
qualitative behavioral-assessment - foot-pad dermatitis - environmental enrichment - stocking density - leg weakness - housing conditions - light-intensity - road transport - gallus-gallus - dairy-cattle
The objectives of this study were to 1) identify determinants of poor welfare in commercial broiler chicken flocks by studying the associations between selected resource-based measures (RBM, potential risk factors), such as litter quality and dark period, and animal-based welfare indicators (ABM), such as foot pad dermatitis and lameness, and 2) establish the breadth of effect of a risk factor by determining the range of animal welfare indicators associated with each of the risk factors (i.e., the number of ABM related to a specific RBM). Eighty-nine broiler flocks were inspected in 4 European countries (France, Italy, the United Kingdom, and the Netherlands) in a cross-sectional study. The ABM were contact dermatitis (measured using scores of foot-pad dermatitis and hock burn, respectively), lameness (measured as gait score), fear of humans (measured by the avoidance distance test and the touch test), and negative emotional state (measured using qualitative behavior assessment, QBA). In a first step, risk factors were identified by building a multiple linear regression model for each ABM. Litter quality was identified as a risk factor for contact dermatitis. Length of dark period at 3 wk old (DARK3) was a risk factor for the touch test result. DARK3 and flock age were risk factors for lameness, and the number of different stockmen and DARK3 were risk factors for QBA results. Next, the ABM were grouped according to risk factor and counted. Then, in a second step, associations between the ABM were investigated using common factor analysis. The breadth of a risk factor’s effect was judged by combining the number (count) of ABM related to this factor and the strength of association between these ABM. Flock age and DARK3 appeared to affect several weakly correlated ABM, thus indicating a broad range of effects. Our findings suggest that manipulation of the predominant risk factors identified in this study (DARK3, litter quality, and slaughter age) could generate improvements in the related ABM and thereby enhance the birds’ overall welfare status
The influence of dietary restriction before and after 10 weeks of age on osteochondrosis in growing gilts
Koning, D.B. de; Grevenhof, E.M. van; Laurenssen, B.F.A. ; Weeren, P.R. van; Hazeleger, W. ; Kemp, B. - \ 2013
Journal of Animal Science 91 (2013)11. - ISSN 0021-8812 - p. 5167 - 5176.
leg weakness - growth-rate - articular chondrocytes - genetic-parameters - epiphyseal growth - production traits - pigs - cartilage - lesions - pathogenesis
Osteochondrosis (OC) is one of the main causes of leg weakness causing premature culling in breeding sows and develops in a short time frame in young growing gilts. Dietary restriction may have different effects on OC prevalence depending on the age of the gilts. The aim of this study is to investigate age dependent effects of dietary restriction, ad libitum versus restricted (80% of ad libitum), on the occurrence of OC in gilts at slaughter (26 wk of age). At weaning (4 wk of age), 211 gilts were subjected to one of 4 treatments of feeding regime. Gilts were administered either ad libitum feeding from weaning until slaughter (AA); restricted feeding from weaning until slaughter (RR); ad libitum feeding from weaning until 10 wk of age, after which gilts were switched to restricted feeding (AR); or restricted feeding from weaning until 10 wk of age, after which gilts were switched to ad libitum feeding (RA). At slaughter, the elbow, hock, and knee joints were harvested. Joints were scored macroscopically for articular surface deformations indicative of OC. Gilts in the RA treatment had significantly higher odds to be affected with OC than gilts in the RR and AR treatments in the hock joint (OR = 3.3, P = 0.04 and OR = 8.5, P = 0.002, respectively), and at animal level (OR = 2.5, P = 0.001 and OR = 1.9, P = 0.01, respectively). Gilts in the AA treatment had higher odds to be affected with OC than gilts in the AR treatment in the hock joint (OR = 5.3, P = 0.01). The results indicate a possible pathway to reduce the prevalence of OC in breeding gilts which will have to last several parities. Switching from restricted feeding to ad libitum feeding after 10 wk of age increases OC prevalence as opposed to restricted feeding after 10 wk of age.
Associations between osteochondrosis and conformation and locomotive characteristics in pigs
Koning, D.B. de; Grevenhof, E.M. van; Laurenssen, B.F.A. ; Ducro, B.J. ; Heuven, H.C.M. ; Groot, P.N. de; Hazeleger, W. ; Kemp, B. - \ 2012
Journal of Animal Science 90 (2012)3. - ISSN 0021-8812 - p. 4752 - 4763.
swine breeding herds - linear type traits - leg weakness - genetic-parameters - exterior traits - danish-landrace - housing systems - finishing pigs - growth rate - sows
Conformation and locomotive characteristics (CLC), i.e., leg conformation and gait movement patterns, may be associated with osteochondrosis (OC) in pigs. Osteochondrosis and CLC increase the risk of premature culling. This study investigated whether CLC have an explanatory value, over the previously modelled effects of sex, feeding, and housing conditions, on the occurrence and severity of OC in several joints and at the animal level. At 154 to 156 d of age, 267 pigs were subjectively scored on 9 conformation and 2 locomotive characteristics. Scoring was performed on a 9-point linear grading scale. For conformation characteristics, score 5 indicated normal conformation and scores 1 and 9 indicated severe deviations from normal. For the locomotive characteristics, score 1 indicated normal locomotion and score 9 indicated severe deviation from normal. At 161 to 176 d of age, pigs were slaughtered and joints were dissected for macroscopic evaluation of OC status. Results showed that swaying hindquarters and a stiffer gait were associated with higher scores for OC in, respectively, the femoropatellar (P = 0.018) and tarsocrural joint (P = 0.005); smaller inner claws as compared to the outer claws of the front legs was associated with lower scores for OC than equally sized claws in the femoropatellar joint (P = 0.021) and on animal level (P = 0.010); steep and weak pasterns of the front legs were associated with higher scores for OC in the elbow joint (P = 0.004) and on animal level (P = 0.018); X-shaped hind legs was associated with higher scores for OC on animal level (P = 0.037); and steep and weak pasterns of the hind legs were associated with lower scores for OC than normal conformation in the tarsocrural joint (P = 0.05). This study found several CLC that were associated with OC in several joints and at an animal level. This study showed that certain CLC might be used as indicators of OC and included in the criteria for selection of replacement animals for the breeding herd.
The relationship between growth and osteochondrosis in specific joints in pigs
Grevenhof, E.M. van; Heuven, H.C.M. ; Weeren, P.R. van; Bijma, P. - \ 2012
Livestock Science 143 (2012)1. - ISSN 1871-1413 - p. 85 - 90.
leg weakness - arthrosis - landrace - animals - traits - weight
Osteochondrosis (OC) is a disturbance of the process of endochondral ossification during skeletal growth. Osteochondrosis is considered the main reason for leg weakness in pigs, which is the second reason for culling in sows, after fertility problems. Previous studies suggest there is a relationship between OC and growth. However, little is known about this relationship, in particular about the timeframe in which growth influences ossification. The aim of the study was to identify the age at which growth and OC are related, and whether this relationship differs between joints. To understand the relationship between the growth pattern and the onset of OC, repeated body weight (BW) measurements and OC scores of 345 pigs were collected. An average of 17 body weight measurements from birth until slaughter at 6 months of age was used. OC was scored macroscopically after slaughter in 24 locations of five joints. Pigs were divided in three defined groups based on the severity of OC; no OC, minor, or severe OC. Until weaning at day 21 no differences in weight and gain were found between the three defined groups. From weaning onwards, pigs diagnosed with minor or severe OC showed higher BWs than pigs diagnosed without OC. The higher weights were due to increased growth before the age of three months. This period might coincide with the window of susceptibility for OC in pigs. The relationship with growth seems to be joint-dependent. Pigs with OC in the elbow joints or with OC in two joints had high BWs, whereas pigs with OC in the femoropatellar joints had low BWs compared to mean BW. Determination of the window of susceptibility and of the relationship between weight gain and OC may help in developing strategies to reduce OC in pig populations
The effects of housing system and feeding level on the joint-specific prevalence of osteochondrosis in fattening pigs
Grevenhof, E.M. van; Ott, S. ; Hazeleger, W. ; Weeren, P.R. van; Bijma, P. ; Kemp, B. - \ 2011
Livestock Science 135 (2011)1. - ISSN 1871-1413 - p. 53 - 61.
leg weakness - finishing pigs - growth-rate - genetic-parameters - production traits - space allowance - slaughter pigs - protein-levels - arthrosis - swine
Osteochondrosis (OC) is seen as the main cause of leg weakness in pigs, leading to welfare problems and economic losses. Environmental factors in pig husbandry, such as the housing system and feeding strategy are expected to influence the prevalence of OC. Therefore, this study investigated the effects of housing system and feeding strategy on the prevalence and severity of OC. In the experiment 345 pigs were used. At an age of 69 days intact boars and gilts were separated and assigned to groups of five or six individuals. A two by two factorial design of housing system and feeding strategy was applied. The housing system was either a conventional concrete floor partial slatted, or a deep litter floor with extra space allowance. The feeding strategy was either ad libitum or restricted to 80% of ad libitum. Pigs were slaughtered at the age of 161–176 days. In total, five joints of the left front and hind limbs were macroscopically assessed for OC on a five-point scale, ranged from no OC through (semi-)loose cartilage fragments. The prevalence of OC in the experimental population was 41.4%, and 12.4% of the individuals had severe lesions. The tarsocrural joint was most affected (30.2%) by OC. OC scores between the different joints were not correlated. Medial sections of joints were most affected (63–100%). Boars were more affected than gilts in the elbow joint. Conventionally housed pigs were more affected than deep litter housed pigs. Ad libitum fed pigs had more OC than restrictedly fed pigs. OC was most prevalent with 57.5% in the pigs on the conventional floor with ad libitum feeding. OC was least prevalent with 33.7% in pigs kept in deep litter housing with restricted feeding. The sex, housing system and feeding strategy did not affect OC in the femoropatellar, metacarpophalangeal, and metatarsophalangeal joints. Our results demonstrate that the OC prevalence can be reduced by applying deep litter floors with extra space allowance and/or restricted feeding in fattening pigs
Economic, ecological, and social performance of conventional and organic broiler production in the Netherlands.
Bokkers, E.A.M. ; Boer, I.J.M. de - \ 2009
British Poultry Science 50 (2009)5. - ISSN 0007-1668 - p. 546 - 557.
egg-production systems - foot-pad dermatitis - leg weakness - sustainability indicators - environmental-impact - respiratory symptoms - livestock buildings - sensory attributes - animal production - walking ability
. In this study, we compared a conventional broiler production system keeping fast growing broilers with an organic broiler production system keeping slow growing broilers in the Netherlands, both managed by one person working a full time year (Full Time Equivalent, FTE). This comparison was based on a quantification of economic, ecological and social indicators. Indicators were quantified using scientific literature and national data sets. 2. The organic system performed better for the economic indicator net farm income per FTE than the conventional system. 3. Regarding ecological indicators, calculations showed a higher on-farm emission of ammonia per kg live weight for the organic system. Moreover, an organic system includes a higher risk for eutrophication per ha due to outdoor access. Emission of green house gasses, use of fossil fuels and use of land required for the production of one kg of live weight is higher for an organic than for a conventional system. This is mainly due to a lower feed conversion in organic production and use of organic feed. 4. The organic system performed better than the conventional system for the social indicators related to animal welfare time spent on walking, footpad lesions, mortality, and sound legs. Regarding the social indicator food safety was found that meat from an organic system contained less antibiotic residues and Salmonella contaminations but more Campylobacter contaminations than meat from a conventional system. 5. Changing from a conventional to an organic broiler production system, therefore, not only affects animal welfare, but also affects economic, ecological and other social issues. In this study, we ran into the situation that some information needed was lacking in literature and quantifications had to be based upon several sources. Therefore, an integrated on-farm assessment is needed, which can be used to develop a broiler production system that is economically profitable, ecologically sound, and acceptable for society.
Vierde proef : lichtschema en lichtsterkte hebben geen effect. Tibiale dyschondroplasie bij kalkoenen
Veldkamp, T. ; Voorst, S. van - \ 2003
De Pluimveehouderij 33 (2003)29/30. - ISSN 0166-8250 - p. 18 - 19.
kalkoenen - pluimvee - diergeneeskunde - pluimveehouderij - dyschondroplasie - botziekten - leg weakness - bewegingsstoornissen - onderzoeksinstituten - organisatie van onderzoek - internationale samenwerking - proefstations - turkeys - poultry - veterinary science - poultry farming - dyschondroplasia - bone diseases - movement disorders - research institutes - organization of research - international cooperation - experimental stations
Onderzoek in EU-verband naar bewegingsstoornissen bij kalkoenen, tibiale dyschodroplasie staat hierbij centraal. Het effect op TD van kalkoenenlijn, temperauur, sekse, leeftijd, lichtschema en lichtsterkte, voersturing en vitamine D werden door het Praktijkonderzoek Veehouderij in zes projecten onderzocht. De bevindingen van de vierde proef
Behaviour of fast- and slow growing broilers to 12 weeks of age and the physical consequences
Bokkers, E.A.M. ; Koene, P. - \ 2003
Applied Animal Behaviour Science 81 (2003)1. - ISSN 0168-1591 - p. 59 - 72.
domestic-fowl - feeding-behavior - stocking density - skeletal disorders - perching behavior - leg weakness - chickens - growth - diets - environments
Behaviour of broilers up to 6 weeks of age has been studied extensively, but little is known what happens after 6 weeks. Insight in the behavioural abilities after 6 weeks may also yield insight in the period before 6 weeks as the disbalance between motivation and physical abilities is more clearly elucidated with increasing weight. The purpose of this experiment was to investigate behaviour in fast- and slow growing broilers to 12 weeks of age and the physical consequences of the prolonged rearing period. Ninety-six 1-day-old female broiler chicks, 48 of a slow growing and 48 of a fast growing line were allocated to 16 floor pens (1.5 m(2) per pen): eight pens of six birds per line. Each pen contained perches and the floor was covered with wood shavings. One day per week, each bird was observed five times, distributed regularly over the day. Behaviour, posture (sitting or standing) and position (floor or perch) of each individual were recorded. After 12 weeks, the birds were killed and post-mortem examination was done to detect physical abnormalities. Fast- and slow growing broilers performed the same behavioural elements, but time budgets of fast- and slow growing broilers were different. Slow growing broilers perched, walked and scratched more than fast growing broilers. Fast growing broilers performed more sitting on the floor, eating and drinking than slow growing broilers. No differences were found for resting, preening, stretching, ground pecking or dust bathing. Time spent on several behaviours changed with increasing age or the posture during behaviour changed with age. Although several physical abnormalities were found in both lines, no correlation was found between physical abnormalities and behaviour. Physical abnormalities seemed not to be so severe to have hampered behavioural activity. The experimental conditions, such as only females, good quality of bedding, low stocking density, and perches seemed to be crucial to prevent serious physical abnormalities and to keep these birds to 12 weeks of age. This study showed that fast- and slow growing broilers are motivated to perform all kinds of behaviour in an environment where that is possible also after 6 weeks of age, but that the ability of performing some behaviours are more and more hampered with increasing age most probably due to their weight. (C) 2002 Elsevier Science B.V. All rights reserved.
Enteropathogenicity of Dutch and German avian reoviruses in SPF white leghorn chickens and broilers.
Songserm, T. ; Roozelaar, D. van; Kant-Eenbergen, H.C.M. ; Pol, J. ; Pijpers, A. ; Huurne, A.A.H.M. ter - \ 2003
Veterinary Research 34 (2003)3. - ISSN 0928-4249 - p. 285 - 295.
bursal disease virus - malabsorption-syndrome - viral-arthritis - stunting syndrome - leg weakness - infection - tenosynovitis - pathogenicity - replication - pathogenesis
The enteropathogenicity of avian reoviruses (ARVs), isolated from chickens affected with malabsorption syndrome (MAS) from The Netherlands and Germany was studied. In the first trial seven different ARVs isolated from MAS cases were inoculated in 1-day-old specific pathogenic free (SPF) white leghorns. The pathogenicity was compared with 2 ARVs isolated from cases of tenosynovitis, namely reference strain S1133 and a Dutch strain. Although a difference in the severity of the clinical disease was observed, all reoviruses could induce vacuolar degeneration and sloughing of the epithelium of the small intestine at day 2 post inoculation (PI) till day 7 PI. Two Dutch and one German ARV derived from MAS causing the most severe intestinal lesions at day 2 PI, were further studied in the second trial using SPF broilers. These reoviruses did not cause weight gain depression in the broilers although lesions in the small intestine were present from day 1 up to day 4 PI and were more severe than in the white leghorn chickens. In one of the inoculated groups apical denuded villi were already present at day 1 PI. At day 7 PI the small intestine of the infected broilers appeared to be normal. Reovirus antigen was detected in the cytoplasm of the enterocytes at the tip and middle section of the affected villi both in layers and in broilers. To study the role of intestinal CD4 + and CD8 + T-cells and macrophages/monocytes in the pathogenesis of ARV, the numbers of these cells of the jejunal villi of one infected and the control broiler groups were compared. CD4 + T-cells were detected in low numbers and only in the infected broiler group at day 14 PI. The numbers of CD8 + T-cells and macrophages/monocytes were significantly higher in the infected broiler group than in the control broiler group at day 7 and 14 PI and at day 7 PI respectively. Our study indicates that the reovirus alone cannot induce intestinal lesions as found in MAS chickens. Moreover, CD8 + T-cells may play a major role in the pathogenesis and or reovirus clearance in the small intestine.
|Impact of floor surface on behaviour, locomotion and foot lesions in cattle
Stefanowska, J. ; Smits, M.C.J. ; Braam, C.R. - \ 1998
Wageningen : IMAG-DLO - ISBN 9789054061717 - 68
rundvee - huisvesting van koeien - vloeren - vloertypen - oppervlakten - diergedrag - voortbeweging - laesies - impact - mankheid - bewegingsstoornissen - leg weakness - cattle - cow housing - floors - floor type - surfaces - animal behaviour - locomotion - lesions - lameness - movement disorders