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1.
1. ISA Brown laying hens (3000) were housed in a perchery in 10 pens, each with 300 birds. The pens varied in size to produce 4 different stocking densities: 9.9 birds/m2 (n = 3), 13.5/m2 (n = 2), 16.0/m2 (n = 2) and 19.0/m2 (n = 3). Observations began at 20 weeks of age and continued until 69 weeks to establish the spatial distribution of the birds, usage of the different resources and the expression of behaviour. 2. Overall, birds spent most time on the perch frame (47%), litter area (23%), slatted floor (17%) and nestbox area (9%). 3. There was no effect of density on the proportion of birds observed on the slatted floor or on the elevated perches but as density increased the proportion on the littered area decreased. 4. Space usage was determined vertically, horizontally and longitudinally. Individual birds were seen to use about 80% of the pen volume available to them. This value was similar for all densities and showed that individuals did not have separate home ranges. 5. Fewer vertical movements were made within the main perch frame at the upper than at the lower levels but movements between the perches of the main frame and the nestbox rails were relatively frequent. This may help birds move up and down through the main frame. 6. Behaviours which decreased in incidence with crowding included moving, foraging and dust-bathing. Behaviours which increased with crowding included standing. Behaviours which were unaffected included resting, preening, prelaying behaviour, comfort behaviour and the minor behaviours. 7. The proportion of birds engaged in feeding and drinking was unaffected by density, except each time the chain feeders (which operated intermittently) ran more hens were seen feeding at the lower densities. This suggests that food delivery stimulated feeding behaviour; there may have been some restriction at the higher densities on birds feeding when and where they wanted. 8. Stocking density had no effect on the frequency of agonistic interactions: threats, lunges, comb/head pecks, chases and fights. 9. The incidence of damaging pecking was low and not density dependent. 10. Increasing density within the range investigated inhibited the expression of a number of behaviours and limited the use of specific resources: bird welfare at 19 birds/m2 may have been very slightly impaired.  相似文献   

2.
Feather pecking and cannibalism are still major problems in alternative systems for laying hens. Literature and practical experience indicate that unfavourable rearing conditions might be important risk factors for the occurrence of these behavioural disturbances during the laying period.Typical rearing conditions of laying hens from 50 rearing units in Germany and Austria are presented. Obvious risk factors during rearing for feather pecking and cannibalism during the laying period were found. Most flocks were kept under high stocking density (mean: 15 pullets per m' useable area) and some flocks had access to litter only after the second week of life or access to raised perches after the fourth week of life. Plumage condition of pullets and laying hens varied widely in non-beak-trimmed as well as in beak-trimmed flocks.The percentage of pullets with damaged plumage was higher in beak-trimmed than in non-beak-trimmed flocks (medians: 53 % versus 30 %, p = 0,022). In laying hens there was a higher percentage of hens with plumage damage in non-beak-trimmed flocks compared to beak-trimmed flocks (medians: 23 % versus 50 %, p = 0,007). Data analysis will be continued, especially with regard to particular risk factors.  相似文献   

3.
1. Coccidiosis, caused by different Eimeria species, is believed to be a more prominent problem in loose-housed layers kept on litter than in battery cages. In this study, the impact and development of Eimeria infections were investigated in layers kept in litter-based, high stocking density systems for loose-housed hens. 2. Layers from 57 flocks on 26 farms were followed by necropsy of a representative sample of birds that died or had to be culled. Coccidiosis was diagnosed in 11 flocks (19.3%) from 9 (31%) of the farms. The outbreaks occurred when the birds were 19 to 32 weeks old. E. maxima was identified in 6 and E. tenella in 3 of the outbreaks. 3. Sixteen of the flocks were also monitored with faecal and litter samples collected at regular intervals. Oocysts were detected in samples from all these flocks. The pattern of oocyst excretion was similar in most of the flocks, with maximum counts at 4 to 8 weeks after introduction to the laying house. There was no significant correlation between the levels of oocysts in faeces and clinical coccidiosis. 4. Raising pullets without any coccidiostat, to increase their chance to develop immunity against coccidia, was not found to decrease the risk of coccidiosis during the production period when compared to the practice of giving amprolium and ethopabate during the rearing period.  相似文献   

4.
1. Fifty-one flocks of laying hens in two high-density loose-housing systems were studied on 25 commercial farms in Sweden as part of a government test programme for evaluating new systems for laying hens. Six different hybrids were used in group sizes ranging from 250 to 5 000 birds. Stocking-densities varied from 10.2 to 19.1 birds per m2 floor area. No birds were beak trimmed. 2. The distribution of birds in the system, the frequency and location of aggressive pecks and feather pecks, the dust bathing activity and the birds' fear reaction to the keeper and to a novel object were measured. Direct behaviour observations were carried out twice per flock, at weeks 35 and 55. 3. The proportion of birds at the different locations was relatively constant across the 8-h observation period in the tiered system, but changed over time in the perch system, which may reflect a difference in access to resources between the systems. At night the top perches/tiers were preferred although when stocking-density increased, other sites were also used. 4. Aggression occurred mainly on the litter or in the nest areas. It did not differ between hybrids, but increased with age in the tiered system. Feather pecks occurred mainly on the litter. Brown hybrids feather pecked more than white ones, while white hybrids reacted more both to the keeper and to a novel object than did the brown hybrids. 5. It was concluded that access to nests was insufficient in both systems, as was litter space. Feed space was insufficient in the tiered system if food requirements increased. Design of the top perches, in the perch system, should be improved to allow birds to perch high up in the system without blocking access to feed etc. for others.  相似文献   

5.
1. Potential risk factors for the occurrence of feather pecking in laying hen growers raised under commercial conditions were investigated on Swiss farms with more than 500 rearing places. On-farm interviews were conducted on a sample of 64 flocks which represented 42.6% of all farms concerned. 2. All variables considered were dichotomised and their univariate correlation with the occurrence of feather pecking was tested for significance at P <0.20 using chi2 tests. Logistic regression with backward elimination was then used with the significant variables to identify the potentially most important factors influencing feather pecking. These variables included stocking density, light intensity, intensity of care, access to elevated perches, access to a roofed and littered outdoor area ('bad weather run'), time of access to the feeding facilities of the housing system, stocking density in the restricted area at the beginning of the rearing period, additional open feeding areas in the beginning and air quality. 3. The final model contained stocking density and access to elevated perches as significant factors (P<0.05). Flocks kept in high density (> or = 10 birds per m2) and with no access to elevated perches were 6.4 (95% Confidence interval 1.7 to 24.2) and 4.0 (95% Confidence interval 1.2 to 12.9) times more likely to be affected by feather pecking, respectively. 4. The study identified 2 risk factors for the occurrence of feather pecking in flocks of laying hen growers reared under commercial conditions. It is concluded that in order to reduce feather pecking chicks should be reared at low density and with access to elevated perches.  相似文献   

6.
1. We examined the effect of density (5, 7, 9 and 11 birds/m2) and season (summerand winter; different hens each season) on stress and behaviour in two flocks of 64 broiler breeder females divided among 8 pens. 2. The hens, approximately the same age and body mass in each season, were maintained on hard-packed ground, without litter, in an open-sided chicken house and were offered the same amount of food each season. 3. Mean house max/min temperatures varied between 18 and 33 degrees C in summer and 7 and 17 degrees C in winter. Mean relative humidity in summer varied between 68% at 08:00 h and 42% at 14:00 h and in winter was 64% at 08:00 h and 47% at 14:00 h. 4. No difference was found in heterophil:lymphocyte ratios among densities and between seasons; however, basophil numbers were higher in winter than in summer indicating prolonged stress in winter. 5. Stereotyped pecking increased with an increase in density and was higher in winter than in summer. Pecking on the ground was higher in winter, but was not affected by density. 6. In summer the hens spent more time lying and eating than in winter, whereas in winter the hens spent more time walking, preening and drinking than in summer. They spent the same amount of time standing in both seasons. None of these behaviours was density dependent. 7. We conclude that season had more of an effect than density on stress and behaviour in broiler breeder hens under the conditions of our study.  相似文献   

7.
Light‐weight, hybrid pullets were reared on litter at 0.070, 0.093, 0.139 and 0.186 m2 of floor area per bird. Flock size was constant at 400 birds per pen and other related factors of management were standardised. Results showed that the different densities of stocking had no commercially important effect on growth rate, food consumption or viability, but feathering was poorer in the more densely populated groups.

At 18 weeks of age, some of the birds from each treatment were transferred to battery cages and others to deep‐litter laying quarters and records of their performance in terms of egg production and quality, food consumption, mortality and body weight gain were taken over a period of one year. The use of high stocking densities during the preceding rearing stage caused no impairment of the performance of layers kept in batteries, but was possibly responsible for a small decline in productivity of layers housed on deep litter.  相似文献   


8.
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   

9.
1. Medium hybrid hens were housed from 20 to 64 weeks in a deep litter house as flocks of 300, 370 and 370 and at stocking densities of 2–4 to 10–7 birds/m2 in three successive laying cycles. Sister birds were housed in cages in an adjacent building as groups of 3 and 4, at 750 or 560 cm2/bird.

2. Hen housed egg production was lower on litter (208 to 235) than in cages (230 to 253). However, the estimated 52‐week values for litter were comparable to or better than standards published by the National Farmers’ Union.

3. Ambient temperatures were well controlled in both houses, but atmospheric dust and ammonia were a problem in the litter system and ammonia was a problem in the deep pit cage house. Litter condition was good at all stocking densities.

4. There was a trend for production to increase with stocking density on litter, but to decrease in cages.

5. Most egg quality variables were similar in the two systems, although there were more dirty eggs from litter and shell thickness was slightly greater in eggs from cages.

6. Body weight increase was initially faster in birds on litter; caged hens were equally heavy by the end of lay, but a greater proportion of their body mass was lipid.

7. The severity of feather damage and loss was correlated with stocking density for hens both on litter and in cages, being worse at the higher densities. Median cage scores were greater than values from litter at low densities but less than those from high densities. Beak trimming reduced feather damage on litter but had no effect in cages.

8. Mortality was low (1 to 3%) for all flocks, except those in year 3 which had not been beak trimmed and which suffered from cannibalism both in cages and on litter.  相似文献   


10.
Light‐weight, hybrid pullets were reared on litter in flocks of 400, 800 and 1200 birds per pen. Floor space allowance was held constant at 0–093 m2 per bird and other related factors of management were standardised. The different sizes of flock had no significant effect on growth rate or mortality, but individual food consumption was significantly higher in the 400‐bird flocks than in the larger units.

At 18 weeks of age, some of the birds from each treatment were transferred to battery cages and others to deep‐litter laying quarters and records of their performance in terms of egg numbers and size, food consumption, mortality and body weight gain were taken over a period of 1 year. The only consistently significant finding was that birds reared in groups of 1200 tended to produce larger eggs (as shown by market grading) and, when housed on deep litter, to eat more food than birds reared in the smaller flocks.  相似文献   


11.
To evaluate the economic effects of subclinical chicken anemia agent (CAA) infection on broiler performance, clinically normal broiler flocks were grouped into two categories: A) flocks in which none of 10 birds sampled at slaughter had antibody to CAA, and B) flocks in which six or more of 10 similarly sampled birds had CAA antibody. Production and performance parameters of 25 flocks in each category were compared. No statistically significant differences were found between category A and category B flocks in major production parameters such as sex, feed manufacturer, type of litter, stocking density, and age at slaughter. However, category A flocks achieved 13% (P less than 0.05) greater net income per 1000 birds, 2.0% better feed-conversion ratio (P less than 0.05), and 2.5% (P less than 0.05) greater average weight per bird than category B flocks. No significant differences in hockburn bonus per 1000 birds (a bonus payable to growers whose broilers have the lowest prevalence of contact dermatitis lesions on the hocks) and mortality were found between category A and category B flocks. These results show that subclinical CAA infection has a substantial, statistically significant effect on commercial broiler performance and profitability.  相似文献   

12.
1. The effect of the presence of loose feathers (on the floor) on the behaviour and plumage condition of laying hens (Lohmann Silver, LS) was studied during the rearing and laying periods. 2. From one day old, 60 birds in each of 4 straw-bedded pens (n = 240 in total) with 6.5 birds/m(2) were either kept under conventional rearing and management conditions (CT: control group with feathers on the floor; n = 120) or in pens from which the feathers were collected from the floor 4 times/week (FR: feathers removed; n = 120). Fifty birds from each of these 4 groups (n = 200 in total) were randomly selected at the age of 16 weeks and allocated to 4 identical pens in a poultry layer house (PH; with perches and 1/3 slatted floor) with access to an outside area (winter garden, WG) at a stocking density of 6 birds/m(2) in both PH and WG. 3. Observations on feather pecking and other behaviours (feeding, drinking, preening, standing, sitting, foraging, moving and dust bathing) were carried out at 8 ages: 6, 10, 15 (rearing period), 20, 25, 30, 35 and 40 weeks (laying period). Feather scoring was carried out at 15, 32 and 39 weeks of age. 4. There were no differences in feather pecking rates, forms (gentle, severe and aggressive pecks) as well as in the plumage condition between groups at the end of the rearing period. 5. Birds in the FR group exhibited lower rates and less severe feather pecking during the laying period. Accordingly, birds in the control group had worse feather condition at 32 and 39 weeks of age. Feather pecking rates within groups were, in general, greater in the afternoon compared to the morning periods. Birds in the control group were more active in walking. 6. Wings, rump, tail and back were the main targets for feather pecking. The majority of feather pecking occurred on the floor (66%) followed by feeding area (26%), perches (4%) and slats (4%). 7. Our results suggest that loose feathers on the floor may play an important role in the development and severity of feather pecking behaviour in laying hens and support the hypothesis (McKeegan and Savory, 1999) that feather pecking can be viewed as redirected foraging behaviour.  相似文献   

13.
This literature review gives information about important behaviour patterns concerning feeding, reproduction and dust bathing of laying hens kept in aviary systems. The behaviour of hens in aviaries is compared to the behaviour of hens living under "close to natural" conditions. Feeding behaviour can be performed to a great extent in aviaries. The same is true for nesting behaviour, while mating behaviour can only be shown in mixed flocks. Dust bathing behaviour in aviaries should be further investigated. Although a litter area is provided and therefore dust bathing is basically possible, further research is needed, to which amount dust bathing behaviour is performed and how it is influenced by composition and height of the dust bathing substrate. Feather pecking and cannibalism can cause more deaths in housing systems with large groups of birds than in cage systems. Considering these results and the results of a first paper dealing with social and resting behaviour, aviaries provide an environment, where hens can perform a large part of their species typical behaviour repertoire. Therefore, under the aspect of behaviour, for laying hens in aviaries the potential to experience good welfare can be evaluated as fairly high.  相似文献   

14.
Management practices, stocking rate and flock size may affect laying hen welfare but there have been few replicated studies in commercial non-cage systems that investigate this. This study used a broad range of physical and physiological indicators to assess the welfare of hens in 36 commercial flocks. Six laying period treatments were examined with each treatment replicated 6 times. It was not possible to randomly allocate treatments to houses, so treatment and house were largely confounded. Three stocking rates were compared: 7 birds/m(2) (n = 2450), 9 birds/m(2) (n = 3150) and 12 birds/m(2) in either small (n = 2450) or large (n = 4200) flocks. In addition, at 12 birds/m(2), in both small and large flocks, birds were subjected to either standard (SM) or modified (MM) management. MM flocks had nipple drinkers and no nest-box lights. Bone strength, fracture incidence, heterophil:lymphocyte (H:L) ratio, live weight, organ weights, serum creatine, serum osmolality, muscle pH and faecal corticosterone were measured on samples of birds at the end of the rearing period and at the end of lay. During the laying period, mortality, production and integument condition were recorded at regular intervals. Birds housed at 9 birds/m(2) had higher mortality than birds housed at 12 birds/m(2) by the end of lay, but not higher than birds housed at 7 birds/m(2). Birds housed at 7 and 9 birds/m(2) had lower percent liver weight, and worse plumage condition than most of the 12 bird/m(2) treatments. Modified management tended to improve plumage condition. There were no clear effects of flock size on the welfare indicators recorded. At the end of the rearing period fracture incidence was almost negligible and H:L ratio was within a normal range. By the end of lay fracture incidence was 60% and H:L ratio was high, with no treatment effect for either measure. This, together with information on faecal corticosterone, feather loss and mortality, suggests that the welfare of birds in all treatments was relatively poor by the end of lay.  相似文献   

15.
1. Limited information is available on how changes in horizontal and vertical space within enriched or furnished layer cages (as defined by Directive 1999/74/EC) influence hen behaviour. This study evaluated the effects of varying minimum cage heights and space allowances on the behaviour of laying hens housed in furnished cages. It was conducted on two flocks of medium brown hybrid hens housed in furnished cages with access to perches and nest boxes on a semi-commercial scale at ADAS Gleadthorpe. 2. Flock 1 consisted of two layer strains (ISA Brown and Babcock 380), housed at two minimum cage heights (38 and 45 cm) and 5 stocking densities between 609 and 870 cm2/bird, with 12 replicates of each of the 20 strain/cage height/stocking density treatment combinations. Stocking density was varied by varying the number of birds per cage from 10 to 7 in standard full-width cages or housing 7 hens in a narrower cage. As a consequence stocking density, group size and trough width per bird co-varied for 4 out of 5 stocking density treatments. 3. Behaviour of flock 1 was sampled at 33 to 36, 46 and 68 weeks of age. At each age one top-tier, one middle-tier and one bottom-tier cage was sampled for each treatment. 4. Few behavioural differences due to cage treatments were detected. Hens at 870 cm2 had shorter feeding bouts than hens at 609 and 762 cm2. Yawning was more common in the cages with greater cage height. 5. Video recordings of flock 1 examined cage height effects on hens' use of vertical space and provided additional data on stretching and self-maintenance activities. No differences in behaviour between 38 and 45 cm cages were found except that scratching head was more common in cages with greater cage height. 6. Flock 2 consisted of two layer strains (Shaver Brown and Hy-Line Brown), housed at 38 and 45 cm and 609, 762 and 1016 cm2/bird, with 18 replicates of each of the 12 strain/cage height/stocking density treatment combinations. Stocking density was varied by housing 10, 8 or 6 hens in standard full-width cages. Behaviour of flock 2 was sampled at 30, 48, 60 and 67 weeks from video recordings. Three cages per treatment from middle-tiers only were sampled at each age. 7. Hens housed at 609 cm2/hen had the longest mean feeding bout, greater than for hens at 762 cm2/hen but not hens at 1016 cm2/hen. More unsuccessful attempts to reach the feeder and sideways and backwards displacements from the feeder occurred at 762 and 609 cm2/hen than at 1016 cm2/hen. A maximum of 8 hens were observed feeding synchronously. 8. These results suggest that changes in horizontal and vertical space over the ranges we studied had little effect on behaviour other than feeding behaviour. Specifying a minimum useable trough space per hen, rather than calculating feeder space from total length of feeder per cage, irrespective of accessibility, might help avoid crowding at the feeder and associated disturbance of feeding bouts.  相似文献   

16.
1. A leg band containing a transponder was fitted to 80 birds in a perchery containing 1,000 birds. 2. The transponder emitted a unique identification number when a bird walked on one of 8 flat antennae on the floor. The recording apparatus was used to measure the amount of time that each of the tagged birds spent on the slatted and littered areas in a 6-week period. 3. Some birds spent long periods of time on the slats, possibly as a means of avoiding repeated attacks. Duration on the slats was greatest in birds with the worst (as opposed to better) feather scores of the head, back and tail regions. 4. Birds that spent long periods on the slats were lighter than other birds at both 39 weeks of age and 72 weeks of age and had greater back, head and tail feather damage, consistent with these birds being victims of pecking. 5. Tagged birds received a social avoidance test outside the perchery at 39 weeks of age, which suggested that birds retreated to the slats in response to pecks rather than just to close proximity to other birds. 6. The failure to find that duration on the slats was related to anatomical indicators of stress (liver, spleen and bursa of Fabricius) suggests that retreating to the slats following pecking attenuates physiological stress responses. 7. We conclude that the provision of areas where birds in a large group can avoid pecking may improve the welfare of a minority of victimised birds.  相似文献   

17.
1. Effects of rearing conditions on behavioural problems were investigated in a cohort study of commercial flocks of laying hens housed in 2 different loose housing systems. The sample population was 120 385 laying hens from 59 flocks of various hybrids at 21 different farms. 2. Logistic regression modelling was used to test the effects of selected factors on floor eggs, cloacal cannibalism and feather pecking. In addition to early access to perches or litter, models included hybrid, stocking density, group size, housing system, age at delivery, identical housing system at the rearing farm and at the production farm and, in models for floor eggs and cloacal cannibalism, nest area per hen. Odds ratios were calculated from the results of the models to allow risk assessment. 3. No significant correlations were found between the prevalence of floor eggs, cloacal cannibalism and feather pecking. 4. Access to perches from not later than the 4th week of age decreased the prevalence of floor eggs during the period from start-of-lay until 35 weeks of age, odds ratio 0-30 (P<0-001). Furthermore, early access to perches decreased the prevalence of cloacal cannibalism during the production period, odds ratio 0-46 (P=0.03). 5. No other factor had a significant effect in these models. Although it was not significant, early access to litter had a non-significant tendency to reduce the prevalence of feather pecking.  相似文献   

18.
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   

19.
1. Faecal samples from 19 commercial, 65 week old free-range egg laying flocks were examined to assess the prevalence and number of parasitic nematode eggs. Data were collected to characterise the housing, husbandry, behaviour and welfare of the flocks to examine possible relationships with the egg counts.

2. Eggs of at least one genus of nematode were present in the faeces of all 19 flocks. Heterakis eggs were detected in 17 (89%) flocks, Ascaridia in 16 (84%), Trichostrongylus in 9 (47%), and Syngamus in 6 (32%). Faecal egg counts (FEC) were greatest for Ascaridia and Heterakis.

3. For each nematode genus, there was no significant difference in FEC between organic (N?=?9) and non-organic (N?=?10) flocks, or between static (N?=?8) and mobile (N?=?11) flocks.

4. FEC were correlated with a range of housing, husbandry and management practices which varied between the nematode genus and included depth of the litter, percentage of hens using the range, and number of dead hens. Statistical analysis indicated relationships with FEC that included light intensity above the feeder, indoor and outdoor stocking density, fearfulness in the shed and on the range, distance to the nearest shelter, and swollen toes.

5. None of the FEC for any of the genera was correlated with weekly egg production or cumulative mortality.

6. Although nematode FEC were highly prevalent among the flocks, the overall lack of relation to other welfare and production measures suggests that these infections were not severe.  相似文献   

20.
1. The present study investigated the effects on Pekin duck health and production of three open water resources in a commercial setting. The three resources were: narrow troughs (15?cm wide and 8?cm deep), intermediate troughs (20?cm wide and 12?cm deep) and wide troughs (50?cm wide and 8?cm deep). A total of 23 flocks of ducks were investigated, with an average size of 4540?±?680 individuals and a final stocking density always under 17?kg/m2.

2. The health of the birds was considered to be of a good standard overall. The only health difference among the resources was that the foot condition of ducks provided with wide troughs was worse than those with intermediate troughs, whilst the foot condition of birds with narrow troughs was intermediate. The open water resources did not differ in their effects on the production measures assessed.

3. Properly managed open water did not have any major negative effects on the health or production of commercial Pekin ducks. Wide, intermediate and narrow troughs did not differ substantially in measures of health or productivity.  相似文献   

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