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1.
This study investigated the effects of pre‐slaughter transport during summer and subsequent water shower spray on broiler meat quality and protein characteristics. Arbor Acres broiler chickens (n = 126, 42 days old, mixed sex, 2.5‐3 kg) were randomly categorized into three treatments: (i) control group without transport (C); (ii) 30 min transport (T); and (iii) 30 min transport followed by 10 min water shower spray and 20 min lairage (T/W). Each treatment consisted of six replicates with seven birds each. Ambient temperature was 32‐35°C during transportation. Results indicated that transport during high ambient temperature denatured myosin and sarcoplasmic proteins, led to decreased protein solubility and resulted in glycogen phosphorylase precipitated to the myofibrillar fraction. Furthermore, meat quality in the transport group showed a pale, soft and exudative (PSE)‐like syndrome. Water shower spray during lairage after transport reduced the degree of protein denaturation and lessened the deterioration of meat quality.  相似文献   

2.
Heat productiorf and the importance of intact feathers for insulation were studied in jackass penguins Spheniscus demersus at various temperatures (5-25°C) by comparing their oxygen consumption in air and water with that of birds whose feather insulation was impaired when they were accidentally covered in partially weathered crude oil. Special attention was given to employing an experimental procedure that could relate oxygen consumption to level of activity. The mean ± SD metabolic rate recorded for normal inactive birds (188 ± 24 kJ kg-1 day-1) was the same in air and water but only 80% of the mass specific rates predicted for non-passerine birds. Wetting a bird increased the inactive rate in air 1,33 times while slow swimming in water above 10°C caused a 1,76-fold increase. At low air temperatures (5°C) postural changes and feather fluffing were associated with a very low rate of 122 ± 29 kJ kg-1 day-1, which we interpret as behavioural control of penguins over energy expenditure. Jackass penguins in sea water at 10°C and above were within their thermal neutral range thus indicating that the water phase of their life cycle is not energetically more expensive than the terrestrial phase. Activity c level of the birds was an important influence on oxygen consumption; we suggest it is the main reason for the variations in metabolic rates within closely related species "? reported in the literature.  相似文献   

3.
Commercial broiler chickens killed in two processing plants, one in the south of England, the other in Scotland, in two seasons (winter and summer) and on two occasions in each season, were used to investigate the effects of killing the birds immediately on arrival or holding them in lairage for one, two, three or four hours. The two most important consequences of holding the birds in lairage were that their body temperature increased and their liver glycogen was depleted. The body temperature increased with the time they were held in lairage, although most of the increase occurred in the first hour and the increase was greater in summer when ambient temperatures were higher. Liver glycogen depletion became apparent after about one to two hours in lairage. No evidence was obtained that the birds were significantly dehydrated or physically stressed by being kept longer in lairage.  相似文献   

4.

I was evaluated the effect of seven different combinations of temperature, air velocity, and relative air humidity on the frequency and duration of eating, drinking, resting, cannibalism, dust bathing, scratching, ground pecking, shivering, and stretching behaviors of turkeys at three different ages. The combinations tested of temperature, relative air humidity, and air velocity were, respectively: 1 (22 °C, 50%, 1 m/s); 2 (26.2 °C, 73.2%, 0.45 m/s); 3 (26.6 °C, 71.2%, 1 m/s); 4 (28.9 °C, 72%, 1.4 m/s); 5 (31.1 °C, 85%, 0.45 m/s); 6 (34.1 °C, 82.1%, 1 m/s); and 7 (34.4 °C, 82.1%, 1.4 m/s) for three ages of birds (61, 96, and 131 days of age). Seven birds were housed per pen, at a density of 3 males/m2, totaling 147 birds in the entire experiment. Each combination was applied for 5 days. The data were analyzed considering the number of times the bird performed the behavior and the time it performed (in seconds). Each pen was considered a repetition. A comparison of the medians was used to compare the treatments by each age. The results showed that young birds were more likely to suffer from the combination of low temperature and high air velocity, reducing their frequency of normal behaviors. Increased humidity at a low temperature raised the frequency of scratching, shivering, and cannibalism behaviors leading to poorer bird welfare. It is recommended that the temperature, relative air humidity, and air velocity combination of 26.6 °C; 71.2%; and 1 m/s, respectively, for young birds, and 22 °C; 50%; and 1 m/s, respectively, for older birds should be used.

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5.
1. An artificial chicken, ‘Gloria’, was constructed to simulate heat exchanges of poultry during transport. Tests of the instrument in a wind tunnel showed it to have insulation properties similar to that of a live bird.

2. Gloria accompanied chickens in two types of transport modules, A (enclosed) and B (open). The average temperature difference between inside and outside the loaded vehicles when stationary and in motion were 14.0 and 7.6 for Type A and 8.8 and 6.0 for Type B. Average air movement while vehicles were in motion was 0.5 m/s for Type A and 3.3 m/s for Type B.

3. Measurements of sensible heat loss from Gloria at different temperatures and wind speeds were compared with published estimates of thermoneutral heat production and thermal insulation for well and poorly feathered chickens to estimate the range of thermal stresses likely to be experienced by chickens in transit.

4. The results showed that the combination of circumstances necessary to ensure thermal comfort for birds both at rest and in motion is very rare (e.g. only between 7 and 8°C for well feathered birds in enclosed vehicles). It is, however, possible to ensure thermal comfort over a wide range of ambient air temperatures by appropriate control of air movement within the vehicle whether at rest or in motion.  相似文献   


6.
The objective of this study was to investigate transportation conditions and behavioral and physiological responses of beef steers to long distance commercial transport throughout the year Japan. Japanese Black × Holstein steers (7.9 ± 0.6 months of age; 320.0 ± 19.0 kg) were transported by truck in spring (n = 8), summer (n = 5), autumn (n = 8) and winter (n = 5). Transport distances (time) were 1020.6 km (25 h including lairage periods): 615.4 km (6.4 h) on expressways, 163.2 km (3.7 h) on arterial roads and 242.0 km (10.5 h) by ferry. The space allowance of the truck was about 1.6 m2/head in all seasons. Internal temperatures of the truck were 14.7 ± 4.7°C in spring, 27.9 ± 2.6°C in summer, 24.4 ± 2.8°C in autumn and 9.2 ± 4.3°C in winter. Although internal noise and airflow velocity of the truck were louder and greater while moving on expressways (101.1 ± 8.3 dB and 1.50 ± 1.50 m/s) than on arterial roads (92.0 ± 15.2 dB and 1.32 ± 1.41 m/s) (both P < 0.05), more steers lay down while moving on expressways (P < 0.001). Blood glucose, plasma cortisol, and serum triiodothyronine (T3) concentrations and ALT activity were higher in spring (all P < 0.05). This could be explained by that vibration acceleration (m/s2) of the truck in the longitudinal direction was greater in spring (?0.19 ± 0.43) than in the other seasons (?0.14 ± 0.09 in summer, ?0.15 ± 0.20 in autumn and ?0.15 ± 0.13 in winter) (all P < 0.05). Heart rate, serum concentrations of T3, total cholesterol, total protein, and AST and ALT activities were higher just after transport than 1 week after transport (all P < 0.05). However, transport stress should be not severe, since no difference between before and after transport was shown on concentrations of plasma cortisol, blood lactate and serum NEFA, serum triglyceride and serum pH and liveweight.  相似文献   

7.
Pheasants hung for 9 d at 10 °G were found to be more acceptable than those hung for 4 d at 15 °G or for 18 d at 5 °G. The birds stored at 15 °G were tough by comparison with those held for longer at the lower temperatures and the clostridia, including Clostridium welchii, increased considerably in the intestines during the storage period. Microbial growth in the muscle tissue was generally found to occur only in birds in which the gut had been perforated by shot. There is an indication that 9 d at 10 °C produced a more “ gamey “ bird than 18 d at 5 °G or 4 d at 15 °G, but the most “ gamey “ birds, independent of temperature, were those in which the muscle was damaged by shot.  相似文献   

8.
The objective of this study was to determine the effect of two transport journeys (3 and 16 h) and four lairage times at the abattoir (3, 6, 12 and 24 h) on some stress indicators in steers to validate the current Chilean legislation of a minimum lairage period of 12 h for cattle arriving at abattoirs.The study was carried out twice, 80 steers in the winter and 80 in the summer of 1999. Forty steers were transported for 3 h and 40 for 16 h. At arrival in the slaughterhouse, the 40 transported steers were randomly divided in four lairage groups. Blood samples were collected before loading at arrival at the slaughterhouse and at slaughter during exsanguination.Mixed models were used to determine the associations between the stress indicators and the independent variables while correcting for the repeated observations on animals. Lairage increased plasma cortisol and PCV values independent of the transport duration. Glucose concentrations in steers transported for 16 h further increased after 3 and 6 h of lairage but decreased after 12 and 24 h of lairage. In steers transported for 3 h, glucose concentrations only increased after 24 h of lairage. After 24 h of lairage, the steers transported for 16 h had increased βHB concentrations compared with those transported for 3 h. Plasma CK activity was increased in steers after transport but was not affected by lairage. The study shows that there is no beneficial effect on the welfare of the animals by a long lairage time at the abattoir.  相似文献   

9.
为了预防和控制鸟撞事件频繁发生,保证飞行安全,作者采用了样线法对咸阳国际机场及周边的鸟类进行了为期1a的调查。结果表明,咸阳及周边地区共有鸟类152种,其中留鸟57种,占总数的37.5%;夏候鸟23种,占总数的15.1%;冬候鸟30种,占总数的19.7%;旅鸟42种,占总数的27.7%。优势种较少,种类包括麻雀、家燕和灰椋鸟,其中燕科鸟类撞机事件的发生率最高。本文就燕科鸟类撞机事件发生规律加以分析并进一步根据具体情况从生态学角度提出了鸟撞灾害生态防治的对策。  相似文献   

10.
Overall mortality among turkeys transported for slaughter in the Czech Republic from 2009 to 2014 was 0.147%. The lowest mortality (0.023%) was found in turkeys transported for distances up to 50 km; longer distances were associated with increasing death rates, with the highest losses (0.543%) recorded for distances from 201 to 300 km. Differences were also found when comparing transport‐related mortality rates according to the season of the year. The highest mortality (0.228%) was associated with transports carried out in summer, whereas the lowest death rates were found in turkeys transported for slaughter in winter (0.105%) and autumn (0.113%). According to the ambient temperatures in which transports associated with the highest death rates among turkeys were carried out (14 to 21°C), it appears that heat stress can be a major factor in the birds’ mortality. However, low ambient temperatures (i.e. below ?2°C) also appear to increase transport‐related mortality, as shown by our results. In addition to shortening the lengths of transport distances, appropriate consideration of prevailing climatic conditions and the sensitivity of turkeys to high and low temperatures during transport may also lead to a reduction in the number of turkeys dying during transport for slaughter.  相似文献   

11.
Hot weather along with high stocking densities can lead to high mortality and decreased performance of broilers, especially during the last week of rearing. Two trials were conducted to test the hypotheses that reduced nighttime and midday temperatures improve broiler live performance and reduce mortality under warm cyclic temperature conditions. In each trial, groups of 306 male broilers were placed in each of 6 environmentally controlled chambers. The warm temperature treatments were control, nighttime cooling, and midday cooling (4 replicates). In the control treatment, diurnal temperatures ranged between 15 and 25°C on d 29 and progressively increased to between 20 and 35°C on d 42. In trial 2, 2 additional chambers housed broilers under thermoneutral conditions. No differences in feed consumption were found within or between trials due to the temperature treatments. The cooling treatments did not improve BW, weight gain, feed conversion, or livability. The birds housed under thermoneutral conditions did not have improved BW. These results suggest that broilers subjected to regular warm cyclic temperature fluctuations for 2 wk prior to shipping are able to acclimatize with no negative impact on BW. Effective environmental temperatures predicted from broiler surface thermal resistance and thermal mass were within 5°C among the treatments.  相似文献   

12.
We report on the first study to track the spatial behaviors of wild giant pandas (Ailuropoda melanoleuca) using high‐resolution global positioning system (GPS) telemetry. Between 2008 and 2009, 4 pandas (2 male and 2 female) were tracked in Foping Reserve, China for an average of 305 days (± 54.8 SE). Panda home ranges were larger than those of previous very high frequency tracking studies, with a bimodal distribution of space‐use and distinct winter and summer centers of activity. Home range sizes were larger in winter than in summer, although there was considerable individual variability. All tracked pandas exhibited individualistic, unoriented and multiphasic movement paths, with a high level of tortuosity within seasonal core habitats and directed, linear, large‐scale movements between habitats. Pandas moved from low elevation winter habitats to high elevation (>2000 m) summer habitats in May, when temperatures averaged 17.5 °C (± 0.3 SE), and these large‐scale movements took <1 month to complete. The peak in panda mean elevation occurred in Jul, after which they began slow, large‐scale movements back to winter habitats that were completed in Nov. An adult female panda made 2 longdistance movements during the mating season. Pandas remain close to rivers and streams during winter, possibly reflecting the elevated water requirements to digest their high‐fiber food. Panda movement path tortuosity and first‐passage‐time as a function of spatial scale indicated a mean peak in habitat search effort and patch use of approximately 700 m. Despite a high degree of spatial overlap between panda home ranges, particularly in winter, we detected neither avoidance nor attraction behavior between conspecifics.  相似文献   

13.
Plasma sodium concentrations, packed cell volume, total plasma protein concentration and dermal skinfold thickness were used to assess the state of hydration of 113 transported calves before and after lairage and in 30 control calves on the farm of origin. Skin thickness increased significantly (P less than 0.05) and total protein increased slightly during transport and decreased during lairage. These changes suggest that transport may cause dehydration and lairage may help in recovery. Plasma potassium concentration decreased during transport, but the effect was inversely related to the distance travelled, and the concentration increased during lairage. These changes are consistent with recovery from initially high cortisol levels at loading. The resting behaviour of 150 transported calves was recorded hourly for six hours. More time was spent resting and sleeping by the transported calves than has been reported for non-transported calves and more still by small transported calves, suggesting that transport is exhausting, that lairage helps recovery and that small calves are more adversely affected. During lairage the numbers of calves asleep decreased to values reported for normal calves, suggesting that 10 hours lairage was adequate. However, small calves did not return to their normal rest patterns within the observation period.  相似文献   

14.
Changes in mastitis‐causing pathogens, pH and water content in composted manure solids (CMS) prepared from digested slurry were evaluated during turning at 2‐day intervals for 8 days (C1–C4). The numbers of streptococci, coagulase‐negative staphylococci and coliforms were 2.6 × 101, 1.7 × 102 and 1.0 × 101 colony‐forming units (cfu)/g in CMS (C4) (summer), and these counts were markedly lower (< 0.05) than those in CMS (C0 and C1). The bacterial counts ranged from 101 to 1.7 × 102 cfu/g in CMS (C4) (summer) and were within approved levels, <1 × 106 cfu/g, indicating a minimal mastitis risk. The temperatures in CMS (C1–C4) increased to 63°C–74°C in summer and 67°C–70°C in winter. The mean pH values in CMS (C0–C4) were 9.2 in summer and 8.7 in winter, and water contents ranged from 61.7% to 69.6% in summer and 73.2% to 66.2% in winter. The significant decrease of pathogenic bacteria in CMS appears to be closely related to temperature >63°C for 8 days, pH 8.7–9.2, and water content 62% to 73%. This study demonstrates that prepared CMS has value as a recycled material with the potential to alleviate udder health issues in dairy cows.  相似文献   

15.
The activity of the ant Camponotus detritus was studied in the dunes of the central Namib Desert. Activity was divided into two components: transit activity and honeydew collection. Temperature governed both forms, but light controlled the initiation and termination of transit activity, which was bimodal in warm conditions and unimodal in cool conditions. No transit activity occurred at night. Ants were active over a surface temperature range of 10-55°C. Owing to a steep thermal gradient above the sand surface during the day in summer, the temperatures which the ants bodies experienced at 5 mm above the sand were 10-15°C lower than surface temperatures; well within the ants' physiological limits. Winds of about 16 km h-1 inhibited activity which ceased when wind speeds reached about 25 km h-1. In summer, the number of ants collecting honeydew was negatively correlated with air temperature while in winter it was positively correlated.  相似文献   

16.
The present study was formulated to find out the status of important season related thermal stress biomarkers of pure-bred (Hampshire) and crossbred (50% Hampshire × 50% local) pigs under the agro-climatic condition of Assam State, India. The experiment was also aimed to study the role of different level of energy ration (110, 100, and 90% energy of NRC feeding standard for pig) in variation of physiological and biochemical parameters in two genetic groups of pigs in different seasons. The metabolizable energy value were 3260, 2936.5, and 3585.8 kcal/kg in grower ration and 3260.2, 2936.6, and 3587 kcal/kg in finisher ration for normal energy (NE), low energy (LE) and high energy (HE), respectively. Both the genetic group of animals were housed separately under intensive system of management. Each pen was measuring 10′ × 12′ along with an outer enclosure. Six weaned piglets (almost similar body weight of average 10.55 kg) of each group were kept in a separate pen. However, after attainment of 35 kg body weight, the animals of a group were divided in two pens of three animals each. The present experiment indicated that average ambient temperature during summer months (27.33–29.51 °C) was above the comfort zone for pigs (22 °C). The significantly (P?<?0.01) higher relative humidity (RH) (%) was recorded in outdoor environment (87.26–91.10%) and in the morning time (86.60–91.10%). The temperature humidity index (THI) during the study period was found to be indicative of thermal stress to the experimental animals during summer (79.55–82.56). Physiological parameters viz., respiration rate (RR) and rectal temperature (RT) were significantly (P?<?0.01) higher in summer season (43.75–72.12 breaths/min. and 102.29–103.23 °F) and non-significantly higher values were recorded in Hampshire pigs. It was also found that the significantly (P?<?0.01) lower RR as well as RT was recorded in the pigs fed with high energy (HE) ration during summer season. Serum triiodothyronine (T3) and thyroxine (T4) concentrations were significantly (P?<?0.01) lower during summer, while both the genetic groups showed significantly (P?<?0.01) higher concentration of serum cortisol during summer season. It was also observed that thyroid hormone and cortisol concentrations were maintained in groups of pig fed vegetable oil incorporated HE diet during summer. From the present study, it is found that the increasing the energy level of the ration might be helpful to minimize the effects of thermal stress during summer.  相似文献   

17.
为了对东洞庭湖湿地鸟类的继续研究提供数据和理论依据,2005年7月~2006年12月采用样方法和样线法对该湿地水鸟进行了调查,共记录到水鸟89种,并对其季节动态格局进行了研究分析,结果表明,全年水鸟种类和数量均是冬季多,夏季少,特别是数量波动有明显的冬季高峰期和夏季低谷期,季节差异非常显著。  相似文献   

18.

Effects of exposing quail eggs to high temperature on the heat tolerance ability and productivity of birds were investigated. Four groups of 600 fertile eggs were randomly selected; the first group was incubated under 37.5 °C and the hatched chicks were reared under a gradual decrease in temperature from 35 to 24 °C (Control). The second group was exposed to 39.1 °C for 2 h/day during 4–14 days of embryogenesis and the hatched chicks were reared under a gradual decrease in temperature from 35 to 24 °C. The third group was incubated under 37.5 °C and the hatched chicks were exposed to 39?±?1 °C for 2 h/day during 4–14 days of age. The fourth group was exposed to 39?±?1 °C for 2 h during 4–14 days of embryogenesis and the hatched chicks were exposed to 39?±?1 °C for 2 h/day during 4–14 days of age. The temperature applied changed (P?<?0.01) embryo weight and incubation period. Birds exposed to high temperature during brooding had superior growth performance, dressed carcass, body temperature and health traits. Birds subjected to 39?±?1 °C during brooding exhibited decreased feed consumption and body weight gain. Finally, this work suggests that thermal acclimation during embryogenesis might offer a practical method for easing heat stress.

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19.
1. Poultry are usually transported in crates which provide the birds with very limited space. Slaughter transport of male turkeys is often carried out using crates that are 40?cm or less in height where it is not possible for them to stand up. There is little information on how this physical restriction over many hours affects the birds.

2. The aim of the study was to compare the welfare of male turkeys transported in crates 40?cm and 55?cm in height. Observations on the birds’ behaviour during lairage, carcass damage and meat quality were carried out after four commercial slaughter transport journeys.

3. Birds in 40?cm crates panted more and lay down more than birds in 55?cm crates during lairage. A large percentage of the carcasses had some damage. Significantly more birds from the 55?cm crates had scratches on their backs than birds from the 40?cm crates. There was no significant difference in meat quality between birds transported in the two crate heights.

4. Both positive and negative effects of increased crate height were established and there is no evidence from this study that merely increasing crate height improves turkey welfare. Other solutions should therefore be sought in order to improve the welfare of birds during transport.  相似文献   

20.
The thermal environment comprises factors which influence an animal's heat exchange through the channels of evaporation, radiation, convection and conduction. The air temperature is often used by itself as an assessment of the thermal environment, but air temperature by itself is inadequate for this purpose unless conditions are standardized with air and mean radiant temperatures equal to each other, free convection, and an insulated floor. Farming environments are not standardized, but climatic investigations allow an equivalent standardized environmental temperature (ESET) to be calculated for a given situation.Information on energy retention and heat loss in the pig has been derived from experiments under standardized conditions. ESET can be used to transfer the results of these experiments to pig farming conditions, and to determine for different types of housing the air temperatures equivalent to the effective critical temperatures found under standardized conditions.Experimental results can then be used to estimate the production losses which occur when ESET falls below the critical temperature, and the decision can be taken on increasing feed or improving heating or nsulation. For pigs in gorups in the body weight range 20–50 kg, the calculated air temperatures for maximum productivity range from 14°C in an insulated house free from draughts to 22°C in an uninsulated house with draughts in winter. Below these temperatures the animals' heat losses increase by approximately 4 kJ/°C per kg per day. For a feed with 1 g  12 kJ metabolizable energy, the increased heat loss leads to an increased feed requirement of 0.3 g/°C per kg per day for maintaining maximum production.  相似文献   

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