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1.
1. Eleven broiler chicken farms, representing 4 production system types, were visited during the last 5 d of the flock cycle: bird and flock details were recorded. Litter friability was assessed at 9 sites within the house, atmospheric ammonia was measured at three sites and bird cleanliness was assessed on a numerical rating scale. 2. For these flocks, hock burn, foot burn and breast burn were measured at the processing plant by standardised assessors. 3. Significant correlations were identified between the percentage of birds with foot burn and average litter score, average house ammonia concentrations and feather score. 4. No correlation was found between the percentage of birds with hock burn or breast burn and average litter scores, average ammonia concentrations or feather score. 5. No correlation was found between stocking density and foot burn, hock burn or breast burn.6. If confirmed, these findings may have implications for the draft EU Broiler Directive, for which it is proposed that permitted stocking density on farm may be determined by the incidence and severity of contact dermatitis measured on plant.  相似文献   

2.
This study aimed to identify risk factors for the prevalence of hock burn, a common disease of broiler chickens that influences the welfare and profitability of affected flocks, using hierarchical logistic regression analysis of routine flock management data. The study identified an association between hock burn and other diseases detected at slaughter and found that the management of flocks around the slaughter period was of particular importance for the control of hock burn, providing a rational basis for intervention.  相似文献   

3.
Rearing conditions and foot-pad dermatitis in Swedish broiler chickens   总被引:1,自引:0,他引:1  
A method of classification of broiler foot-health status was developed to estimate the prevalence of foot-pad dermatitis in Swedish broilers. Data on foot health were collected from 101 commercial broiler flocks at slaughter. The producers were asked to fill in a questionnaire on rearing conditions and equipment for every flock.

Lesions were commonly observed; only 62% of the birds were classified as being without lesions, 32% had mild lesions only (discoloration, erosions) and 6% had severe lesions (ulcers). Flocks reared in houses equipped with small water cups had significantly (P < 0.05) higher prevalences of foot-pad dermatitis than flocks reared with water nipples. Thick layers of litter, regardless of litter material, also resulted in significantly (P < 0.05) higher prevalences of foot-pad dermatitis than litter layers thinner than 5 cm.  相似文献   


4.
1. Standardised data on husbandry were recorded for a flock of birds in one house on each of 150 broiler farms in the UK during the 4 d prior to slaughter.

2. For each flock, the incidence of birds found dead on arrival (DoAs) and the Meat Hygiene Service carcase rejection records were recorded at the slaughterhouse.

3. The mean percentage of birds in each flock found DoA was 0·12% (range 0–0·64%) and the mean percentage of Total Carcase Rejects (TCRs) for each flock was 1·23% (range 0·07–5·51%).

4. A general linear model was developed to examine factors associated with flock percentage DoAs. Assuming a linear relationship, all other factors remaining the same, a one percentage point (PP) increase in small/emaciated birds will result in a 0·155 PP increase in DoAs and a 1 PP increase in wheat in diet 4 will result in a 0·003 PP decrease. An increase by one in the total number of vaccines administered will cause a 0·029 PP decrease in DoAs, a 1 g increase in live weight at slaughter will be associated with a 0·000043 PP increase and a 1 PP increase in mortality on farm would be associated with a 0·000044 PP increase. A 1 PP increase in Ross birds decreases DoAs by 0·0004 PPS: there is also a seasonal effect.

5. The model developed for flock percentage TCRs found that a 1 PP increase in wheat in diet 3 will result in a 0·052 PP decrease in TCRs and a 1 PP increase in Ross birds will cause a 0·009 PP decrease. A 1 PP increase in birds culled on farm will be associated with a 0·03 PP increase in TCRs and the diagnosis of disease during the flock cycle increases TCRs by 0·397 PPs. A one day increase in age at slaughter will result in a 0·046 PP increase in TCRs.  相似文献   


5.
AIM: To compare the effects of four stocking densities (5, 10, 15 or 20 birds per m2) on the performance, carcass characteristics and selected welfare indicators of broiler chickens. METHODS: A total of 756 day-old male broiler chicks were assigned as six replicates of 13, 25, 38 and 50 birds per pen, to stocking densities of 2,000, 1,000, 667 and 500 cm2 floor space per bird, respectively. The birds were housed in floor pens in an environmentally controlled room. Normal commercial diets were fed ad libitum and fresh water was freely available throughout the 5-week study period. Liveweights of birds and feed intake were recorded at weekly intervals. Data on carcass parameters and welfare indicators (moisture, gait scores, feather scores, breast and hip lesions, and foot pad and hock burns) were obtained on Day 35. Adrenal glands were removed at slaughter, weighed and examined histologically to determine the total proportion of cortical and medullary tissues. RESULTS: During the study, the birds at the lowest density grew faster (p<0.001-0.01) and consumed more (p<0.001- 0.01) feed than those at the other three stocking densities. The liveweight gains and feed intake of birds reared at densities of 10, 15 and 20 birds per m2 were similar (p=0.11-0.83 and p=0.17-0.57, respectively). Stocking density had no influence on the feed/weight gain, mortality or carcass characteristics. No breast or hip lesions were observed in carcasses from any of the groups. The weight and structure of the adrenal glands were similar across all groups although the staining of medullary tissue of birds was most intense in the highest stocking density group. As stocking density increased, so did moisture and gait score, hock and foot pad burn scores, and the feather score was adversely affected. CONCLUSIONS: The data showed that the relationship between stocking density and productivity traits was not linear in nature, in accordance with other studies. Under the conditions of the current study, the performance, mortality and carcass characteristics of broilers grown at densities of 10, 15 and 20 birds per m2 were similar. There were some welfare implications at high population densities as indicated by adverse effects on litter quality, gait scores and the incidence of hock and foot pad burns.  相似文献   

6.
This observational study was conducted to identify flock of origin level factors associated with mortality during transport to slaughter of 1 090 733 Manitoba broiler chickens in spring and early summer. The death loss in transit was 0.346% (3778 birds). Death loss on the farm of origin during the growing phase of production and bird body weight at slaughter were associated with increased mortality in-transit. Death loss during production significantly exceeded, while crowding of growing birds was significantly less than, European proposed animal welfare standards.  相似文献   

7.
1.?Severe foot and hock dermatitis in broiler chickens can reduce growth rate and increase susceptibility to bacterial infection, affecting both profitability and welfare. However, little is known about the underlying physiological changes associated with foot and hock lesions.

2.?This study compared global hepatic gene expression in control birds and those with ammonia-induced foot and hock lesions using Agilent 44?K chicken oligonucleotide microarrays (8 birds per group).

3.?In total, 417 genes were differentially expressed of which 174 could be mapped onto the genome. Genes associated with energy metabolism, thyroid hormone activity and cellular control were affected, while there was also evidence of an up-regulation of genes linked to a pro-inflammatory response.

4.?It is conceivable that pain is the underlying cause for the observed changes in energy metabolism genes.

5.?Changes in hepatic gene expression provide new information on how a chicken's physiological mechanisms alter to cope with foot and hock lesions. The findings support other data indicating that birds with increased severity of lesions are likely to be in pain and that growth will be compromised. Reduction of the incidence of dermatitis by improved husbandry should therefore benefit both welfare and commercial performance.  相似文献   

8.
Chicken welfare as indicated by lesions on carcases in supermarkets   总被引:1,自引:1,他引:0  
1. The extent of visible lesions in British broiler carcases was investigated in order to discover the extent of any poor welfare. It is well established that hock burn and some other injuries can occur during housing of broiler chickens, whilst other injuries can occur during handling. 2. Three hundred and eighty-four whole conventionally reared British Farm Standard Grade A chickens were scrutinised in supermarkets to assess the frequency of 15 kinds of lesions. Six lesions were analysed histopathologically and this showed that hock burn would have occurred several days pre-mortem, red alular and wrist bruise were very likely to have occurred pre-mortem, whilst red parson's nose and scratches were likely to have occurred pre-mortem. 3. Many broiler carcases in the supermarkets had dermal lesions: 0.82 had hock burns, 0.45 a red parson's nose, 0.32 a red alular, 0.21 wrist bruises and 0.21 had at least one scratch on a leg. The frequency of the larger hock burns increased with body weight. 'Organic' chickens had half as many hock burns as conventionally reared broilers, perhaps because of differences in litter quality or leg strength. 4. The sample studied indicates that painful lesions which would result in poor welfare are frequent in broilers slaughtered in the UK. The Grade A chickens observed exclude birds with obvious visible defects because these birds would have had the blemishes removed and the carcase would have been portioned. Hence the frequencies of lesions in farmed birds would be higher than those reported here.  相似文献   

9.
1. A cross-sectional observational study was carried out to investigate spatial, temporal and management aspects of foot-pad dermatitis in Swedish broilers. The efficacy of a control programme was evaluated. 2. Flock information on producer, breed, foodstuff manufacturer, region, abattoir, date of slaughter, age at slaughter, planned and actual stocking density was recorded. A total of 6988 flocks, representing approximately 110 million broilers, was examined. A total of 175 broiler producers from 15 geographical regions is represented. 3. The total foot-pad score per flock ranged from 0 to 200, with a mean of 34.7 and a standard deviation of 40.9. 4. Simple linear regression analysis showed that the mean total score on a weekly basis decreased (P 0.001) over time, mainly because of a decrease in the prevalence of severe foot-pad lesions. 5. There was an association (P 0.05) between slaughterhouse, foodstuff supplier and geographic region respectively and the mean total foot pad score of the flocks slaughtered.  相似文献   

10.
The effect of hatch location and diet density on the prevalence of footpad dermatitis and growth performance in broiler chickens was studied. Broilers (Ross 308), incubated at 2 different hatch locations but originating from the same parent stock, were subjected to 2 feeding programs differing in energy content (2,750 vs. 2,950, 2,850 vs. 3,050, 2,900 vs. 3,100, and 2,900 vs. 3,100 kcal/kg for starter, grower I, grower II, and finisher diets, respectively) in a 2 × 2 factorial design (6 replicates per treatment combination). Broilers were housed under conditions and managed according to Dutch practice. Hatch location did not affect hatching results nor the prevalence and severity of footpad dermatitis, but did affect BW gain, feed, and water intake. A significant interaction was found between hatch location and feeding program; broilers fed the low-energy (LE) program had a better performance when hatched at Location 2 than at Location 1, whereas performance was similar for the high-energy (HE) broilers hatched at both locations. Broilers fed the LE program had similar BW gain but a higher feed conversion due to a higher feed intake as compared to broilers fed the HE program. In addition, moisture content of the litter in the pens with LE birds was higher than in pens with HE birds. As a result, broilers fed the LE program had more footpad dermatitis and hock burns at d 36 as compared to broilers fed the HE program. It is concluded that the HE feeding program is preferred to prevent footpad dermatitis and hock burn, and with respect to growth performance. The differences in growth performance between the 2 hatch locations merit further study but indicate the importance of the incubation and hatching environment and posthatch handling in relation to the growth performance of broilers on-farm.  相似文献   

11.
Broiler chickens are often intestinal carriers of Campylobacter. During processing, Campylobacter may be spread over the carcass. Thus, undercooked chicken meat, or other foods contaminated by raw chicken can act as a source of infection to humans. This study was conducted to identify risk factors for chicken flocks being colonized with Campylobacter. Eighteen chicken farms with altogether 62 chicken compartments were studied for 1 year with visits during each growing period and sampling of chicken caecal contents at slaughter. Four to six subsequent flocks were raised in each compartment during the study. A detailed questionnaire was used to record farm parameters such as building materials, feed and water equipment, hygiene and management routines. Campylobacter prevalence varied between farms, between growing periods within the farms and also during the year, with lowest prevalence during the spring. Campylobacters were isolated from 27% out of 287 flocks. Only two farms were negative at all samplings. Often the flock following a positive flock in a compartment was negative, indicating that normal cleaning and disinfecting routines are sufficient for eliminating the bacteria from the house. Usually only one serotype was found in each positive flock. Campylobacter occurrence increased with the age of the chickens at slaughter, and also with flock size.

Univariable chi-square tests were done of the association between possible risk factors and Campylobacter prevalence. Factors associated with higher Campylobacter prevalence in flocks were lack of or diffuse hygiene barriers, increasing flock size, increasing age at slaughter, short vs. long empty periods, wet litter beds, other poultry nearby or staff handling other poultry, flocks divided before slaughter, staff loading to slaughter at several farms and occurrence of mice. Under Swedish conditions, water does not seem to be a source of infection for chickens. Origin and handling of day-old chickens, feed additives, houses and litter were not associated with higher Campylobacter prevalence.  相似文献   


12.
1. The objective was to compare the effect of two litter types (wheat straw and wood shavings) and two different rearing conditions (Treated and Control) on welfare indicators, broiler performance, carcase injuries, particularly hock and foot pad dermatitis (FPD), litter characteristics and meat quality. 2. Treated conditions were characterised by a low stocking density (11 birds/m(2)), short photoperiod (16 h light: 8 h dark) and a large amount of litter (3 to 4.5 kg/m(2), respectively, for wheat straw or wood shavings). Control conditions were a high stocking density (14 birds/m(2)), long photoperiod (23 h light:1 h dark) and small amount of litter (2.3 to 3 kg/m(2), respectively, for wheat straw or wood shavings). In addition, the effects of two widely used litter materials, wheat straw and wood shavings, were investigated. 3. The combined effects of lower stocking density, greater amount of litter material and a photoperiod similar to the natural one, reduced the occurrence of FPD in Treated groups keeping the FPD score under the European threshold. 4. Improved rearing conditions led to faster growth rate associated with inferior feed efficiency, whereas litter type exerted negligible effects on broiler performance. 5. Litter moisture content, nitrogen and ammonia released by the litter were lower in Treated groups than Control groups. The use of wood shavings resulted in lower moisture and nitrogen concentrations in the litter.  相似文献   

13.
1. An experiment was conducted to determine whether different moisture levels of litter and perches with different hygienic conditions are involved in the manifestation of foot pad dermatitis in White Leghorn layers. 2. Four different treatments were compared: dry litter and dry perches; dry litter and wet perches; wet litter and dry perches; and wet litter and wet perches. Temperature, pH, air humidity and ammonia changes in the pens were monitored. 3. The mean prevalence of foot pad lesions in groups 1, 2, 3 and 4 was 17%, 13%, 49% and 48% respectively. The overall incidence of foot pad lesions in birds reared on dry litter was 38%, and in birds reared on wet litter 92%. 4. When the air temperature was above 20C,an increasing moisture content in the litter was associated with an increasing incidence of foot pad dermatitis. However, when the air temperature was below 20C there were no new cases of dermatitis in any of the 4 treatments. There were no significant differences in litter pH or ammonia between the 4 treatments when compared over the whole experiment. 5. Although the incidence of lesions was not significantly affected by the presence of wet perches, the area of the lesions tended to be in groups with wet patches than in groups with dry perches. 6. It is suggested that moisture and temperature are important contributing factors for the occurrence of foot pad dermatitis in laying hens. Wet perches may contribute to the severity of such lesions.  相似文献   

14.
Foot pad dermatitis (FPD) is a welfare concern in broiler chickens characterized by ulcerated lesions on the pad of the foot, which results from prolonged contact of foot pads with wet litter. During Canadian prairie winters, barn moisture levels tend to increase due to reduced ventilation as a means of conserving heat and minimizing costs. However, there are no published benchmarks regarding the prevalence of foot pad dermatitis in broilers reared in western Canadian provinces such as Alberta, Canada. As such the objectives of the current study were to evaluate practical means of assessing FPD in Alberta broilers as well as on-farm management practices which correlate with higher prevalence of foot pad dermatitis. A management-practices survey and 3 foot pad assessment methods were used to benchmark foot pad dermatitis in 32 broiler flocks throughout the province of Alberta. Four flocks per farm were sampled from a total of 8 commercial broiler farms. Per flock, 200 birds were assessed on-farm, 3 processor-line scores were taken at the processing plant, and 600 foot pad samples were assessed post-processing. The prevalence of foot pad dermatitis by assessment method was benchmarked on a per-flock basis at 28.65% on-farm, 26.17% on the processing line (processor-line), and 31.83% for samples taken off the processing line (processor-sampled). On-farm and processor-sampled assessment results were highly correlated (r = 0.90) compared with processor-line and on-farm (r = 0.77) and processor-line and processor-sampled results (r = 0.72; P < 0.001). Specifically, processor-line assessments were not found to be reliable when repeated (P > 0.10). On farm, wheat straw was used by the majority of Alberta’s producers (62.5%) and was associated with a higher prevalence of foot pad dermatitis per flock (40.6%). In contrast, pine shavings was associated with lower FPD prevalence (6.4%; P < 0.001), but was used by only 21.9% of producers in Alberta. Primary results from this field study support the use of on-farm FPD assessments rather than processor-line-based assessments, and a shift away from wheat straw as a broiler litter substrate.  相似文献   

15.
A prospective cohort study was conducted in the Brittany region to identify the risk factors related to foot-pad dermatitis (considered an indicator of animal well-being) in chicken and turkey broilers reared under commercial conditions. Factors related to the shed, equipment, litter management and stocking density were recorded; the dependent variable was the prevalence of lesions observed on the slaughterhouse chain. Lesions were scored from 0 (no lesion) to 3 (severe lesion). Our survey lasted from May 1999 to October 2000. Fifty flocks of chicken broilers (15 farms), 27 flocks of female turkey broilers (21 farms) and 41 flocks of male turkey broilers (27 farms) were surveyed. In chicken broilers, 10% of flocks were of high quality (80% of birds with score 0) and this was related to the use of concrete floors with a thin layer of wood shavings. In turkey broilers, 48% of female and 46% of male flocks were of bad quality (>10% of birds with score 3). A poor fan ventilation system (<150 m3/h/kg) was a significant risk factor. Turkey flocks of high quality were not observed. Stocking density had no influence on the prevalence of foot-pad dermatitis. We concluded that it is possible under high commercial stocking densities to have flocks with a low prevalence of foot-pad dermatitis in chicken broilers, whereas it is not in turkey broilers. Hence in chicken broilers, implementing a monitoring system based on the observation of foot-pad dermatitis prevalence at slaughter appears to be more appropriate than to legislate stocking density. In turkey broilers, it would probably be necessary either to reduce the stocking density drastically or to investigate new systems of floor drainage.  相似文献   

16.
1. Experiment 1, comparing wood shavings and ground straw bedding with peat, was performed on 7 broiler farms over two consecutive batches during the winter season. Experiment 2, assessing the effect of elevated (30 cm) platforms, was conducted in three farms replicated with 6 consecutive batches.

2. Footpad lesions were inspected at slaughter following the Welfare Quality® (WQ) assessment and official programme. Hock lesions, plumage cleanliness and litter condition were assessed using the WQ assessment. Litter height, pH, moisture and ammonia were determined.

3. Footpad condition on wood shavings appeared to be worse compared with peat using both methods of assessment and was accompanied by inferior hock skin health. WQ assessment resulted in poorer footpad and hock skin condition on ground straw compared with peat. Farms differed in footpad and hock skin condition. Footpad and hock lesions were not affected by platform treatment. Peat appeared more friable than ground straw. The initial pH of wood shavings was higher and moisture was lower than in peat, but at the end of production period there were no differences. Ground straw exhibited higher initial and lower end pH, and was drier in the beginning than peat. Litter condition and quality were not affected by platform treatment.

4. This study provides new knowledge about the applicability of peat as broiler bedding and shows no negative effects of elevated platforms on litter condition or the occurrence of contact dermatitis in commercial environments. The results suggest a complicated relationship between litter condition, moisture and contact dermatitis. Furthermore, it is concluded that the farmer’s ability to manage litter conditions is important, regardless of the chosen litter material. Peat bedding was beneficial for footpad and hock skin health compared with wood shavings and ground straw.  相似文献   


17.
We investigated the genotype diversity and dynamics of Campylobacter in a commercial broiler flock during rearing and slaughter. In total, 220 Campylobacter jejuni isolates collected on four sampling occasions during rearing and from routine sampling during slaughter were subtyped by SmaI macrorestriction and pulsed-field gel electrophoresis, PFGE. Eight different SmaI types were found. During rearing, a subsequent addition of genotypes occurred, with two SmaI types found at 2 weeks of age and six types on the day before slaughter. All types that were detected in more than one isolate were also found on all succeeding sampling occasions, including the slaughter sampling. Two new types were found in the slaughter samples. In two-thirds of the individual birds sampled the day before slaughter, more than one SmaI type were found, although there was a clear tendency for dominance of one type in individual birds. Our results show that multiple genotypes of C. jejuni may be present in a commercial broiler flock during rearing and even in gastrointestinal tracts of individual birds. Both recurring environmental exposure and genetic changes within the population may explain the genotype diversity. Although the distribution of genotypes varied between different sampling occasions, we found no indication that any subtype excluded another during the rearing of the broiler flock.  相似文献   

18.
Because of the increasing demand for raw cuts and processed products, there is a trend to producing very heavy broilers. Breeds that are used for such kinds of production have been intensively selected for growth rate and breast meat yield, and birds are reared for a longer period than standard broilers. This study was to evaluate the effects of increasing slaughter age on technical and economic factors, including production efficiency and environmental costs, bird welfare, and breast meat quality in a modern heavy broiler line. Five groups of 300 male Ross 708 chickens were reared until slaughter ages of 35, 42, 49, 56, or 63 d. Increasing age at slaughter from 35 to 63 d resulted in a 7.4-fold increase (P < 0.01) in mortality rate (5.21 vs. 0.70%). It also increased (P < 0.001) the slaughter weight and ADFI of birds 2.5- and 1.4-fold, respectively, without affecting their G:F. Under our experimental conditions, economic profit evaluated through the net gain reached a maximum at 42 d. The moisture and ammonium content of litter increased (P < 0.05 and P < 0.01, respectively) rapidly during rearing concomitantly with increased (P < 0.05) occurrence and severity of contact dermatitis and decreased (P < 0.05) walking ability and activity of birds. Thermal comfort also decreased (P < 0.05) greatly as early as 42 d of age. Changes in carcass quality occurred mainly between 35 and 56 d of age, with a progressive increase (P < 0.001) in breast and leg yield, whereas body fatness was barely affected by age. Major changes in breast meat traits were observed between 35 and 49 d of age, with an increase in muscle pH at 15 min (P < 0.01) and 24 h (P < 0.001) postmortem and reduced (P < 0.001) lightness and drip loss. The protein and lipid content of raw breast meat also increased (P < 0.05 and P < 0.01, respectively) with age. Taking into account the main aspects of sustainability, we could recommend slaughtering chickens of heavy line at 42 d of age.  相似文献   

19.
SUMMARY A survey of the weekly causes of mortality was carried out in a flock of 64,000 broiler chickens in Western Australia. Some 6.86% of the flock died or was culled in the period from day-old to slaughter and were examined post mortem. The most important cause of death, acute death syndrome (ADS) (36%), occurred during all weeks of production and 74% of affected birds were male. A comparison of liver biotin content made between 120 ADS-affected birds and 60 clinically normal flockmates established that the biotin status of ADS-affected birds was adequate.  相似文献   

20.
1. Four randomised block experiments were conducted to determine the role of litter moisture, excreta and alternative bedding materials on the development of footpad dermatitis in growing turkeys. 2. Adding water to the litter increased external and histopathological scores independently of the presence of excreta. Fully developed lesions were induced by the application of water to dry litter in 2 to 4 d. 3. Footpad lesions were associated with discomfort during walking in one experiment and body weight was lower in birds on wet compared with dry litter. 4. Footpad lesions had virtually healed 15 d after transfer of the turkeys from wet to dry litter although histopathology assessment showed some residual tissue repair. 5. Long barley straw was associated with high footpad scores on wet and dry treatments. The footpad scores for turkeys on reprocessed cardboard chips were similarly high whereas scores were similar on paper litter and wood shavings whether dry or wet. 6. It was concluded that high litter moisture alone was sufficient to cause footpad dermatitis in young turkeys and that footpad dermatitis should be minimised by the maintenance of dry litter.  相似文献   

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