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1.
Blood samples from sarcoptic mite-infested pigs were evaluated for effects of mite infestation and cold and ambient temperatures on lymphocyte blastogenic responses and for effects of mite infestation on serum cortisol concentrations. In experiment 1, sarcoptic mite-infested and noninfested pigs were housed in cold (5 to 15 C fluctuating) and thermoneural (25 C) environmental chambers for 5 weeks. Differences were not observed (P greater than 0.10) in blastogenic responses to phytohemagglutin or pokeweed mitogen between lymphocytes from infested and noninfested pigs on postinfestation days (PID) 7, 21, 28, and 35 in either environmental chamber. When lymphocytes from noninfested pigs were cultured with sera from infested pigs, alterations of blastogenic responses were not detected. Cortisol values were higher (P less than 0.05) in sera from sarcoptic mite-infested pigs, compared with those from noninfested pigs, at 4 PM on PID 14 and 4 AM and 10 AM on PID 15. Cortisol values were higher (P less than 0.05) in sera obtained at 10 AM on PID 14 and at 10 AM on PID 15 from pigs housed in cold chambers, compared with those from pigs housed in thermoneutral chambers. Interactive effects between sarcoptic mite infestation and cold ambient temperatures were not observed. At 4 AM on PID 15 (experiment 2), cortisol values were higher (P less than 0.05) in sera of infested pigs, compared with those in noninfested pigs. Seemingly, sarcoptic mange in pigs did not alter mitogen-induced lymphocyte blastogenic responses, but did increase serum cortisol concentrations, indicating that sarcoptic mange may be a stressor in pigs.  相似文献   

2.
Commercial layers were inoculated with F strain Mycoplasma gallisepticum (MG) and housed in either conventional chicken houses or the lower-stress environment of biological isolation units. At the end of 2 weeks, all treatment groups were placed in environmental chambers and subjected to 4 hr of heat stress (40 C with a dew point of 21 C). Rectal temperature, an indicator of response to high heat, was monitored. Rectal temperatures of F strain MG-inoculated hens housed in the conventional chicken house environment were significantly higher than those of uninoculated controls, whereas rectal temperatures of hens held in isolation units were comparable to those of their uninoculated controls.  相似文献   

3.
Ten susceptible and ten resistant pigs to malignant hyperthermia were used to observe the effects of exercise and ambient temperature on selected physiological parameters. Pigs were submitted to a ten minute exercise on a treadmill operating at a speed of 1.8 km/h and inclined to 11 degrees. Exercise in the first group was at an ambient temperature of 14 degrees C, and in the second at 29 degrees C. The right carotid artery was previously cannulated for blood pressure measurements and for repeated blood sampling during exercise. Arterial pressure, heart rate, rectal and cutaneous temperatures were recorded. Levels of cortisol, creatine kinase and its isoenzymes were measured. At 14 degrees C, exercise caused some physiological adjustments in susceptible animals; heart rate, skin temperature and cortisol levels increased (P less than 0.05). In resistant pigs, only the heart rate was elevated significantly following exertional stress at 14 degrees C. Exercise at 29 degrees C produced severe stress and marked physiological changes: heart rate, rectal and skin temperatures and cortisol levels increased significantly in both susceptible and resistant swine. At 29 degrees C, susceptible pigs also had higher levels of serum cortisol, total creatine kinase and MM isoenzyme (P less than 0.05) compared to resistant pigs. The results indicate that, following exertional or thermal stress, susceptible pigs undergo more extensive physiological changes than do resistant pigs. Similar levels of stress prior to slaughter may trigger physiological changes which in the susceptible pigs would likely result in pale, soft exudative myopathy.  相似文献   

4.
The effect of supplementary administration of recombinant bovine somatotrophin (rbST) on the renal tubular handling of sodium in crossbred 87.5% Holstein cattle housed in normal shade (NS) or mist-fan cooled (MF) barns was evaluated. The cows were injected with 500 mg rbST at three different stages of lactation. The MF barn housed cows showed a slightly decreased ambient temperature and temperature humidity index, but an increased relative humidity. Rectal temperature and respiration rates were significantly lower in cooled cows. The rbST treated cows, housed in NS or MF barns, showed markedly increased milk yields, total body water, extracellular fluid and plasma volume levels, along with a reduced rate of urine flow and urinary excretion of sodium, potassium and chloride ions and osmolar clearance, in all three stages of lactation. Renal tubular sodium and water reabsorption were increased after rbST administration without any alteration in the renal hemodynamics. Lithium clearance data suggested that the site of response is in the proximal nephron segment, which may be mediated via increases in the plasma levels of aldosterone and IGF-1, but not vasopressin, during rbST administration.  相似文献   

5.
Three trials using 80 Yorkshire x Hampshire x Duroc crossbred pigs (avg initial wt, 6.9 kg) were conducted to determine the effects of four dietary vitamin E levels (11, 110, 220 and 550 IU/kg of feed) on the humoral and cell-mediated immune response and performance of 4-wk-old weanling pigs housed at two nursery temperatures (19 or 30 degrees C). Interactive effects of temperature and vitamin E were not observed for any measurements. Serum and liver vitamin E levels increased linearly with increasing level of dietary vitamin E, but performance, cortisol, antibody levels and mitogen-induced stimulation indices were not affected by supplemental levels of vitamin E. Average daily gain and feed intake were higher (P less than .01) for pigs housed at 19 degrees C than for pigs housed at 30 degrees C, but feed:gain ratios, mitogen stimulation index of white blood cells, plasma cortisol levels and antibody titers were not altered. Although supplemental vitamin E above the NRC estimated requirement increased serum and liver vitamin E concentrations, no differences were observed in humoral and cell-mediated immune response, cortisol levels or performance for weanling pigs housed at either 19 or 30 degrees C temperatures.  相似文献   

6.
Eight gopher snakes were given amikacin (5 mg/kg of body weight IM) and were housed at ambient temperatures of 25 C or 37 C. Snakes housed at 37 C had a larger volume of distribution, and a more rapid body clearance of amikacin while the apparent half-life was not changed significantly. The minimum inhibitory concentrations of amikacin against isolated snake pathogens were determined at both temperatures. Bacteria were twice as sensitive at 37 C than at 25 C. The data indicated that amikacin should be given IM at a dose schedule of 5 mg/kg (loading dose) followed by 2.5 mg/kg every 72 hours, and that snakes should be housed near the high end of their preferred optimum ambient temperature during treatment.  相似文献   

7.
Housing temperature effects on growth, feed utilization and feed digestion of 12, 7-mo-old Standardbred colts were evaluated for 22 wk beginning in late November. Colts were assigned to one of two treatments: housed in a barn heated at 10 degrees C (warm) or housed in a barn with no external heat supply (cold). All horses were allowed outdoors for 4 h daily. Mean temperatures of the warm and cold barn from November to April were 10.9 +/- .66 and -5.2 +/- 1.72 degrees C, respectively. Hair coat weight of cold-housed colts was 1.4- to twofold (P less than .05) that of warm-housed colts from December through April but declined for both groups from fall to spring. All colts were fed a pelleted diet to meet National Research Council (1989) energy guidelines for moderate gain (.65 kg/d). Warm-housed colts gained weight 29% more rapidly (P less than .01) than cold-housed colts (.67 vs .52 kg/d). Skeletal growth, measured by cannon bone circumference, wither and croup height, was not affected by housing temperature. Nutrient digestion by both groups of colts was compared to that of mature, warm-housed ponies. Ponies had longer (P less than .05) digestive tract retention times and higher digestibilities for every nutrient than the young horses did. Although retention times by all colts were similar, cold-housed colts digested more ADF and less phosphorus (P) than did warm-housed colts (P less than .05). Over time, digestibilities of DM, NDF and P declined (P less than .05) for colts but not for ponies. Maintenance energy needs were estimated at 34.6 kcal/kg BW for cold-housed colts vs 26.3 kcal/kg BW for warm-housed colts. Young horses need 1.3% more maintenance energy per Celsius degree decrease in temperature below 0 degree C. To sustain a constant moderate gain, daily DE intake needs to be increased .7% per Celsius degree decrease in ambient temperature below 0 degree C.  相似文献   

8.
Bovine lactoferrin was administered orally, in feed, to six bottlenosed dolphins (Tursiops truncatus) before they were transported for approximately six hours; their stress responses were compared with those of five untreated dolphins. During the journey the dolphins had an increased plasma concentration of cortisol, and lymphopenia, eosinopenia and mild neutrophilia, indicating a stress response. The administration of lactoferrin did not affect the function of the dolphins' polymorphonuclear leucocytes, but affected their leucogram by maintaining the number of circulating eosinophils.  相似文献   

9.
Dolphins in a captive environment are exposed to various kinds of stresses. Handling and transportation are stressful events for terrestrial mammals, and such stress may affect immune system function and increase susceptibility to infectious diseases. The same phenomenon could occur in dolphins, however, few studies have reported this in dolphins. The objective of this study was to evaluate the relationship between stress and polymorphonuclear (PMN) cell function of dolphins during transportation. Four bottlenose dolphins (Tursiops truncatus) were transported for 6 hr by truck. Serum cortisol levels, leukograms, phagocytosis, and superoxide production of PMN cells were evaluated during handling and transportation compared to resting values. The mean serum cortisol level was significantly increased during handling and transportation (p<0.05) when compared with the resting values. White blood cell (WBC) counts, eosinophil counts, phagocytosis, and superoxide production of PMN cells during handling and transportation stages decreased significantly in comparison with the resting stage (p<0.05). The concentration of serum cortisol was significantly correlated with the results of the WBC counts, eosinophil counts, superoxide production, and phagocytosis (p<0.01, p<0.05, p<0.05, and p<0.001, respectively). The present results indicate that handling and transportation are stressful events for dolphins and could affect their PMN cell functions, thereby leading to the impairment of the immune system.  相似文献   

10.
Three trials using 240 weanling pigs were conducted during winter months to determine the influence of nursery temperature ("comfortable" vs "cold") on the response of weanling pigs to added vitamin C (700 ppm) or E (55 IU/kg) to a corn-soybean meal diet. A "comfortable" temperature schedule (27 C initially with a weekly 2 C drop) was maintained in one nursery, with the temperature schedule in the "cold" nursery about 8 C lower. Plasma concentrations of vitamin C and vitamin E were elevated when the respective vitamins were added to the diet, but were not consistently influenced by nursery temperatures. Daily gain, daily feed intake and feed efficiency were not improved with the added C or E. Daily feed intake was increased and feed-to-gain ratios were larger for pigs housed in the "cold" nursery compared with pigs housed in the "comfortable" nursery; however, daily gains were similar in the two environments. Pigs housed in the "cold" nursery were slightly stressed, as indicated by heavier adrenal glands, but the antibody response and serum glucocorticoid concentrations were not significantly affected by either diet or temperature.  相似文献   

11.
温度是影响种公猪繁殖性能的重要因素.温度过高和过低都会导致种公猪精液品质下降、性欲下降,配种母猪妊娠率、产仔率和仔猪成活率下降等.因而为种公猪提供适宜的环境温度,避免热应激或冷应激是保证种公猪身体健康和繁殖力的重要举措.文章结合温度影响种公猪繁殖力的机理,阐述了环境温度与种公猪繁殖力的关系以及在种公猪饲养管理过程中为保...  相似文献   

12.
本研究旨在评价河北省三大区域（冀北燕山、太行山区和冀中南平原）羊场夏季绵羊的热应激程度,并分析温热环境参数与绵羊个体生理指标的相关性,为改善羊舍环境提供理论依据。选择3个区域12个规模化羊场,自动检测并记录夏季羊舍的环境温度和相对湿度2个月,同时检测各场绵羊的直肠温度和呼吸频率。结果表明,冀北燕山、太行山区和冀中南平原的羊舍日均温度分别达24.3、28.5和28.7℃,温湿指数（THI）分别达72.40、79.91和79.47,冀北燕山区域绵羊正遭受轻度热应激,而太行山区和冀中南平原地区的绵羊遭受中度甚至重度热应激,可见,夏季河北省舍饲绵羊的热应激防控需要引起关注,加强夏季的防暑降温措施刻不容缓。从绵羊个体生理指标看,3个区域绵羊的直肠温度范围为39.1～39.8℃,呼吸频率为42～114次·min-1,直肠温度与环境温度、THI之间均未表现出显著相关关系（P>0.05）,但与相对湿度间表现出显著的线性负相关关系（P<0.05,r=0.60）;呼吸频率与环境温度、THI之间表现出极显著正相关关系（P<0.01,r=0.84;P<0.01,r=0.87）,与相对湿度间未表现出显著相关关系（P>0.05）。因此,通过羊舍温湿参数和THI的测定可以推断绵羊的个体生理状况,对实际生产中舍饲羊热应激的预防及相关疾病的诊断提供依据。  相似文献   

13.
Although livestock experience many stressors throughout their life, one of the most commonly experienced, and most difficult to control, is stress caused by fluctuations in environmental temperatures that extend beyond the thermoneutral (TN) zone for an animal. In swine, cold stress has long been recognized as a main cause of neonatal morbidity and mortality. A possible explanation for this increased morbidity and mortality may be related to their inability to generate a febrile response. Previously, we reported that the acute phase immune response, including the generation of fever, after exposure to lipopolysaccharide (LPS; Escherichia coli O111: B4; Sigma-Aldrich, St Louis, MO, USA) is substantially altered in neonatal pigs maintained in a cold environment (ie, 18°C). Neonatal pigs that were maintained in a cold environment and administered LPS experienced a period of hypothermia coupled with altered endocrine and proinflammatory cytokine responses that could prove detrimental. In cattle, we previously reported differences in the acute phase immune response of two diverse breeds of Bos taurus cattle (Angus and Romosinuano) when maintained under TN conditions and exposed to LPS. More recently we have reported that differences in the stress and immune responses of Angus and Romosinuano heifers varies, depending on whether the cattle were housed at either TN or heat stress air temperatures. Our data clearly show that even intermittent periods of heat stress similar to that experienced in production environments can have significant effects on the stress and innate immune responses of cattle. Understanding the effect of thermal stress on livestock is critical to developing and implementing alternative management practices to improve their overall health and well-being.  相似文献   

14.
冷热应激对蛋鸡生理生化指标的影响   总被引：10，自引：0，他引：10  
１８周龄的伊莎蛋鸡在１３～１８℃、６０％～７０％ＲＨ的环境条件下，饲养至２３周龄（产蛋率为７０％）时，随机分为８组，（每组８只），用于模拟蛋鸡在南京地区自然急性冷热应激条件下的部分生理生化指标变化。试鸡分别在３０℃－７０％ＲＨ、３５℃－７０％ＲＨ、３５℃－９０％ＲＨ和２℃－５５％～７２％ＲＨ条件下进行试验，每种处理均设有一组适宜温度组为对照，试验期均为７天。结果表明，急性热应激时，蛋鸡血液的ＰＣＶ、ＰＣＯ２、ＬＤＨ的活性、血糖、血清钙、Ｔ４、Ｔ３和Ｅ－１７β的含量均与对照组有显著（Ｐ＜００５）或极显著（Ｐ＜００１）降低；直肠温度较对照组有极显著升高（Ｐ＜００１）。急性冷应激时，蛋鸡直肠温度较为恒定，血液ｐＨ、ＰＣＯ２、Ｈｂ、ＰＣＶ、血糖、Ｃｏｒ含量和ＬＤＨ活性略有升高，但除血糖外差异均不显著（Ｐ＞００５），血清钙、Ｔ４、Ｔ３和Ｅ－１７β的含量降低，且Ｔ４和Ｅ－１７β的含量与对照组差异极显著（Ｐ＜００１）。  相似文献   

15.
Four prepubertal pigs were prepared with venous catheters and housed in metabolism cages. Plasma and saliva samples were taken at 15-min intervals over a 105-min period and analysed by radioimmunoassay for total (i.e. free and bound) cortisol content. Adrenocorticotrophic hormone (ACTH) was given i.v. at three different doses (0.5, 1.0 and 2.0 mg) after the second sample and the cortisol responses were compared with pretreatment values and levels observed after saline vehicle administration. Basal levels of salivary cortisol were approximately 10% of those in plasma. ACTH induced significant increases in plasma and salivary cortisol but in no case was a dose/response relationship detected. Plasma cortisol showed a maximum increase of approximately 230% whereas salivary cortisol increased only by about 130%, indicating that salivary cortisol is a less sensitive indicator of adrenal activity than plasma cortisol in this species. Estimation of salivary cortisol concentrations may offer practical advantages for the assessment of stress responses in intensively housed pigs.  相似文献   

16.
低温高能饲粮对笼养产蛋鸭生产性能及生化指标的影响   总被引：10，自引：0，他引：10  
本文研究了低温高能饲粮对笼养产蛋鸭生产性能和生化指标的影响。结果表明 :(1)低温使日采食量、料蛋比显著升高 (P<0.01) ,使日产蛋量、产蛋率显著降低 (P<0.05) ;高能饲粮则使日采食量显著降低 (P<0.05) ,使日产蛋量、产蛋率有升高的趋势 ;在低温下提高饲粮代谢能水平使日采食量、料蛋比显著降低 (P<0.05) ,使日产蛋量、产蛋率有升高的趋势。(2)低温使血清中T3 水平显著升高 (P<0.05) ,而T4 水平略有降低 ;高能饲粮使T3 水平略有降低 ,T4水平略有升高。在适温下和低温下提高饲粮代谢能水平使T3 水平有升高趋势 ,而T4 水平有降低趋势。 (3)低温显著升高血清中游离脂肪酸和尿酸水平 (P<0.01) ,显著降低血清中葡萄糖水平 (P<0.05) ;高能饲粮显著升高血清中游离脂肪酸和葡萄糖水平 (P<0.05) ,使血清中尿酸水平有降低的趋势。在适温下和低温下提高饲粮代谢能水平有使血清中游离脂肪酸、葡萄糖升高的趋势 ,使血清中尿酸有降低趋势  相似文献   

17.
Normal, scaleless, and artificially depilated chicks were exposed for 30 min to an ambient temperature of 11° C when 3 to 14 d old and their cloacal temperatures recorded every 15 min. The three groups of chicks demonstrated a greater resistance to cooling as a function of increased age, but both depilated and scaleless chicks develop this ability at a significantly slower rate than normal birds. Scaleless chicks are no more resistant to acute cold stress as they mature than comparable chicks without their normal body insulation.  相似文献   

18.
Lambs were used to evaluate the effect of acute heat stress (HS) or restraint and isolation stress (RIS) on endocrinological and immunological functions. In Exp. 1, lambs were exposed to HS (35 degrees C) and control lambs (CN) were exposed to 21 degrees C for 24 h in two replicates (n = 8 lambs total per treatment). Samples of serum were obtained at frequent intervals for evaluation of cortisol; whole blood was obtained for total and differential leukocyte numbers and lymphocyte blastogenic function. The time-trends for cortisol between HS and CN lambs were different following treatment (P less than .005), but neither leukocyte numbers nor lymphocyte blastogenesis in response to mitogens were affected by acute exposure to the elevated ambient temperature. In Exp. 2, lambs (n = 6 per treatment) were given a 6-h RIS treatment and control lambs remained in their home stanchions (CON). Plasma and serum were obtained frequently during treatment and continued until 24 h after the onset of treatment. Plasma was evaluated for adrenocorticotropic hormone (ACTH) and serum was assayed for cortisol. Samples of whole blood also were obtained before and at 6, 12 and 24 h after the onset of treatment for determination of total and differential leukocyte numbers and lymphocyte blastogenic responses to mitogens. Both ACTH and cortisol were elevated in response to RIS; the profiles of these hormones over the 24-h bleeding period differed for RIS and CON lambs (P less than .001).(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
The type of equipment used to transport circus tigers, environmental factors experienced during transport, and resultant body temperatures of tigers transported were surveyed during hot and cold weather conditions with six different circus tiger acts. Dataloggers recorded interior and exterior temperatures, relative humidity, and radiant heat at 5-min intervals during each trip. Microdataloggers fed to the tigers recorded body temperature and were recovered from eight Bengal (Panthera tigris tigris), Siberian (P. t. altaica), or Bengal-Sumatran (P. t. tigris-P. t. sumatrae) cross tigers from four different circuses. Three basic types of systems were used by circus acts to transport tigers: freestanding cages mounted on wheels that were winched or pushed into a semitrailer for transport, cages built into the trailer itself, and weather-resistant units transported on flatbed railcars or flatbed truck trailers. The highest temperature encountered inside a trailer was 37.3 degrees C in hot weather conditions, but overall, temperatures were usually between 21.1-26.7 degrees C. Temperature inside the trailers did not appear to be affected by movement and did not generally exceed ambient temperatures, indicating adequate insulation and passive ventilation. During cold weather trips, the lowest temperature inside the trailers was -1.1 degrees C, occurring during an overnight stop. Interior temperatures during cold weather transport stayed 2-6 degrees C warmer than ambient temperatures. The body temperatures of the tigers were unaffected by extreme temperatures. The only changes observed in body temperature were increases of 1-2 degrees C caused by activity and excitement associated with loading in several groups of tigers, regardless of whether it was hot or cold weather. Whenever measured, carbon monoxide and ammonia were below the detectable concentrations of 10 and 1 ppm. respectively. Overall, transport did not appear to have any adverse effects on the tigers' ability to thermoregulate.  相似文献   

20.
Cats need a minimum amount of space even in animal shelters. In this study the effects of single caging and cage size on the behavior and stress level of domestic cats were investigated. Six neutered cats (2–15 years old) that had been housed in a group for at least 7 months were moved to three kinds of single cages (small, medium and large) by rotation on a Latin square design. They experienced each cage size for 6 days. Cats could use vertical dimensions when housed in a group room and the large cage. Behavioral observation was conducted for 3 h in the evening, and stress levels were assessed by urine cortisol‐to‐creatinine ratios. The amounts (estimated proportions) of time spent in locomotion and social/solitary play were lower even in large cages than in group housing (both P < 0.05). Conversely, the amount of time spent resting tended to increase when housed singly (P = 0.104). The urine cortisol‐to‐creatinine ratios of singly housed cats tended to be higher than that of group‐housed cats (P = 0.086). The results indicate that cats become less active when they are housed singly in cages regardless of the cage size. Cats seem to feel no undue stress even in small cages if the stay is short.  相似文献   

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