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1.
Six Nubian pack donkeys were used to determine variations in rectal temperature (RT), respiratory rate (RR), and heart rate (HR) during the early rainy season. The donkeys exhibited a diurnal range of RT, RR, and HR of 34.7 to 38.7°C, 15 to 75 breaths/minute, and 36 to 72 beats/minute, respectively, with peak mean values at 2:00 pm and a trough shortly after sunrise (7:00 am). The amplitude of the diurnal rhythm of RT and RR was not correlated with the diurnal range of ambient temperature (AT) and relative humidity (RH). Although mean diurnal RTs were positively correlated with corresponding ATs, mean daily RTs were not significantly correlated with corresponding ATs. Diurnal and daily variations in RT of donkeys, like those of other ungulates, therefore, appear to reflect an endogenous rhythm, which may be largely independent of fluctuations in environmental thermal load. The mean maximum AT and RH, and the corresponding RR and HR values, fell above the normal range for donkeys in the tropics. The season was meteorologically stressful to the donkeys, imposing significant changes in the RT, RR, and HR parameters requiring responses to maintain homeostasis. The values of the amplitude in RT, RR, and HR obtained in individual donkeys were higher than the corresponding values obtained during the hourly recordings, indicating that it is more important to evaluate the individual's vital parameters in reaching conclusion of fitness for work in donkeys. The hourly recordings have shown the hours of the day (11:00 am to 4:00 pm) that are potentially meteorologically stressful for donkeys to be used for packing during the season.  相似文献   

2.
3.
Equine body temperature taken with a non-contact infrared thermometer (NCIT) does not correlate well with the equine body temperature taken with a digital rectal thermometer (DRT), when it comes to absolute temperatures. There is significant variation in body temperature readings depending on the site at which the temperature was taken. NCIT may still may have, in that it does seem to be able to reliably detect when temperatures are more than that which is clinically normal, and does not seem to give falselyelevated readings in clinically normal horses. In horses that resent having their temperatures taken rectally, the NCIT seems to offer the equine clinician a quick and easy way to at least determine whether the horse's temperature is at or more than normal, even if it does not agree with DRT results.  相似文献   

4.
以一家营业近20年的高尔夫球场为研究对象,采用试验法、对比分析法及单因子污染指数法,分析雨季高尔夫球场周围地表水水质特征。研究表明:雨季,球场两个内湖水的总氯、氨氮、总磷均大于农田沟渠水;与国家地表水环境质量Ⅲ类、Ⅱ类水质限值相比,球场内外水体所含的总磷未超标;球场内湖水Hg,Cr超标,球场外围水只有球场出水口处Hg超标。球场内外水体农残未检出。  相似文献   

5.
The objective of this study was to compare the rate of ovulation when deslorelin and/or human chorionic gonadotropin (hCG) was administered in mares in both the transition period and the ovulatory season. A total of 200 Paint Horses, Quarter Horses, and crossbred mares were used during the transition season (July to September) and the ovulatory season (October to February) of the southern hemisphere. The animals were divided into four groups. In the control group (n = 72), mares received 1 mL of saline; in deslorelin group (n = 171), 1.5 mg of deslorelin was administered by intramuscular (IM) injection; in hCG group (n = 57), 1,667 IU of hCG was administered IV; and in hCG + deslorelin group (n = 438), 1.5 mg of deslorelin (IM) and 1,667 IU of hCG (IV) were administered. The drugs were administered after follicles ≥35 mm in diameter were identified and grade III uterine edema was observed. At 48 hours after application, ultrasonography was performed to detect ovulation. During the transition period, the ovulation rates were 4.3% (control), 78.6% (deslorelin), 50% (hCG), and 73.3% (hCG + deslorelin). During ovulatory season, the ovulation rates were 16.4% (control), 68.8% (deslorelin), 60% (hCG), and 73% (hCG + deslorelin). There was no significant difference (P > .05) in the ovulation rate between the groups or the periods, except that the control group was lower than all others. Furthermore, both hCG and deslorelin are viable options for inducing ovulation during the transition period before ovulation season.  相似文献   

6.
针对农村养蚕房屋紧、投入成本高、效益低的实际情况,在春蚕期进行了5龄立体条桑一日两回育研究,结果表明立体条桑育具有节省养蚕用房、生产用具简单、用桑量少、蚕茧产质量高于对照区等优点。  相似文献   

7.
藏羊是青海地区特有的牲畜品种,生活在高海拔气候严寒,生长条件恶劣的环境下。但由于青藏高原冬季枯草期漫长,在枯草期内牧草供给缺乏,造成藏羊的体重损失严重,甚至会影响藏羊的正常生长发育,引发藏羊死亡。为进一步验证冬季藏羊补饲的效果,于2018年10月15日至2019年5月30日,从青海省达日县的一个藏羊养殖场选择50头2岁的母羊作为试验对象,按照随机原则将其划分为试验组和对照组,每组25头,试验组羊群在进行传统放牧养殖的基础上每天补充青干草0.4 kg,混合精饲料0.1 kg,对照组藏羊按照常规放牧方式进行管理,并在试验前、试验中期和试验末期各进行称重,测量增重和增重率,研究结果表明,在寒冷季节放牧养殖模式下,通过对羊群进行适量的饲料补充能增加机体的营养供给,试验组羊群在试验中期、试验末期的平均增重量分别为2.78、3.64 kg,增重率分别为13.11%、16.32%,而对照组的平均增重量和增重率呈现负相关,由此得出冬季寒冷季节补充适量的饲料有利于藏羊安全越冬,并维持身体膘情。  相似文献   

8.
海北高寒草甸植被在生长期辐射能量收支探讨   总被引:9,自引:0,他引:9  
李英年 《草地学报》2001,9(1):58-63
在晴天,海北高寒草甸植被辐射的各收支项均有明显的日变化规律,在中午13~14h最大。地表净辐射通量日变化在-158~499W·m-2,8~9h到18h地表面净得到热量,地表处于吸热阶段,18h~翌晨8h区域净损失热量。反射率在早晨与傍晚最高,13h左右最低。植物生长季的4~9月,中午反射率约在0.20~0.22,早晨与傍晚在0.24~0.49,不同季节的3d日平均反射率为0.25,11h~15h平均为0.21。  相似文献   

9.
利用最小二乘法对温带气候条件下874窝杜洛克和659窝大约克母猪的繁殖性状数据进行统计分析。结果表明:胎次、季节对杜洛克和大约克母猪的断奶再发情间隔、产仔数、21日龄窝重等繁殖性状影响显著(P<0.05);哺乳期对杜洛克和大约克母猪的断奶再发情间隔影响显著(P<0.05)。母猪1~7胎繁殖性状呈现先升高后降低的趋势,随着哺乳期的延长母猪断奶再发情间隔先减少后增加,夏季高温高湿对母猪产生热应激,影响其生长性能的发挥。在生产中,加强对初产和六胎以上的母猪饲养管理,及时淘汰老龄母猪,在夏季做好母猪的防暑降温等工作,推荐采用21~28d断奶。  相似文献   

10.
谷氨酰胺对高温下黄羽肉鸡增重及血液生化指标的影响   总被引:2,自引:3,他引:2  
选用42日龄健康“岭南黄”黄羽肉鸡60只,饲养于32±2℃的封闭舍内,随机分成4组,A组为对照组,饲喂基础日粮,B、C和D组为试验组,分别在基础日粮中添加0.2%、0.5%和0.8%的谷氨酰胺,试验期14 d。试验结果表明,高温下在日粮中添加谷氨酰胺能提高黄羽肉鸡的平均日增重,其中添加0.5%谷氨酰胺的效果显著(P<0.05),其显著提高49、56日龄的血清总蛋白含量(P<0.05),添加0.2%谷氨酰胺显著降低56日龄的血清尿素氮含量(P<0.05),添加谷氨酰胺对血清中的葡萄糖含量无影响(P>0.05)。说明谷氨酰胺有缓解肉鸡高温应激的作用。  相似文献   

11.
A total of 607 calving intervals on 99 Ayrshire cows with parities from 1 to 10 and belonging to one dairy herd at Iringa in the southern highlands of Tanzania were analysed to study the effect of parity and season or month of calving on the subsequent calving interval. In addition, 22 calving intervals incorporating a superovulatory cycle were compared with those of 52 controls that had calved around the same period.The average (mean±SEM) age at first calving was 985±16 days. The effect of parity on calving interval was highly significant (p<0.001). Cows that calved in December, at the beginning of the rainy season, exhibited the shortest calving interval (404±13), while those that calved in September/October, in the dry season, exhibited the longest average calving interval (466±20 days), although this difference was not significant. Prior treatment with follicle-stimulating hormone to induce superovulation, significantly lengthened the average calving interval (579±28 vs 457±15 days; p<0.001).It was concluded that both parity and FSH treatment affected the calving interval. However, season (rainy vs dry) or month of calving did not influence this interval.  相似文献   

12.
Sixteen estrous cycles from 10 cyclic mares were randomly assigned to a control or sulpiride group (n = 8 each). All mares received 1,500 IU of human chorionic gonadotropin (hCG) (hour 0) during estrus with a follicular diameter ≥32 mm. Mares were scanned every 12 hours until ovulation. In the treatment group, beginning at hour 0, each mare received 1.5 mg/kg of sulpiride every 12 hours intra-muscularly until ovulation or formation of a luteinized unruptured follicle (LUF). Concentrations of luteinizing hormone (LH) and prolactin (PRL) were measured by radioimmunoassay. In each group, there were 10 preovulatory follicles for the eight cycles. The ovulation rate (9/10, 90%) was similar in the control and sulpiride groups. Two mares formed an LUF, which was first detected at hours 48 and 72 for the sulpiride and control mares, respectively. The interval from hCG to ovulation was 49.5 ± 11.1 and 43.5 ± 5.8 hours, for the control and sulpiride groups, respectively (P > .5). LH followed the typical preovulatory surge pattern, with no difference between groups (P > .5). Sulpiride administration increased PRL concentration in treated mares at 24 (P < .1), 36, and 48 hours (P < .05) after treatment. In conclusion, sulpiride administration every 12 hours increased PRL concentration in treated mares after 24 hours of the beginning of treatment. However, at this time window and concentration, PRL did not have any effect on ovulation. The control mare that developed an LUF had a PRL concentration similar to other ovulatory control mares (always ≤10 ng/mL).  相似文献   

13.
The responses were monitored of young crossbred calves vaccinated against tropical theileriosis during the winter against a field tick challenge in the disease season. Thirty-eight calves below 2 months of age, born after the end of the disease season, were selected at an organized farm. Twenty-five animals were vaccinated with Theileria annulata (Hisar) cell culture vaccine (developed at CCS HAU Hisar laboratory) after the end of the disease season and 13 calves were kept as non-vaccinated controls. These calves were observed for their susceptibility to theileriosis in the new disease season. There was an increase in antibody titre in 18 of the 25 vaccinated animals one month after vaccination. The antibody titre then declined gradually, but remained higher than those of the non-vaccinated animals at month 0. No fever or other clinical signs of tropical theileriosis were observed in any of the vaccinated animals. Nine out of 25 (36%) vaccinated calves showed occasional piroplasms (<;0.5%) in blood smears. All the vaccinated animals withstood the field tick challenge. On the other hand, 9 of the 13 (69%) unvaccinated calves exhibited occasional piroplasms, and included three clinical cases of tropical theileriosis. These observations suggest that young crossbred calves vaccinated with the T. annulata (Hisar) cell culture vaccine at the end of the disease season were relatively resistant during the next disease season.  相似文献   

14.
The effect of 1% moxidectin/cydectin at 0.2 mg/kg live weight on gastrointestinal nematodes and on the growth of calves, weaners and cows was investigated in five communal areas on the highveld of Zimbabwe. Three field experiments were carried out between March 1996 and June 1997. In experiment 1, treatment was administered in all five areas at the end of the rainy season in March 1996, followed by a further treatment at the beginning of the dry season in May/June 1996. In experiment 2, the treatment was administered in three areas at the end of the rainy season in March 1997. In experiment 3, treatment was administered in one area at the beginning of the dry season in April 1997. Large numbers of eggs were present in the faeces of calves and weaners at the start of experiments 1 and 2. Epg values were lower in cows and in all age categories in experiment 3. There was a statistically significant reduction in epg values in calves, weaners and cows following treatment with a reduction of 90–99% in all cases except in cows in experiment 3, where no meaningful assessment was possible owing to the low egg counts in both the treated and control cows. The dominating larval types in faecal cultures were Cooperia and Haemonchus. Trichostrongylus, Oesophagostomum and Bunostomum were also found. Following treatment, Haemonchus was suppressed far more than Cooperia. This may be related to a longer residual effect against abomasal parasites like Haemonchus in comparison to small intestinal worms like Cooperia. Anthelmintic treatment conferred significant weight gain advantages (p<0.05) on treated calves, weaners and cows. The weight gains are discussed in relation to disease and nutrition.  相似文献   

15.
The effect of heat stress on changes in milk production, rectal temperature, respiratory rate and blood chemistry was evaluated in three groups of six mature Holstein, Jersey and Australian Milking Zebu (AMZ) dairy cows. These animals were subjected to a cool environment when the mean temperature-humidity index (THI) was 72+/-1.4 (dry bulb temperature of 22.2-24.4 degrees C and relative humidity of 100-60%) during the month of December. This experiment was repeated during the hotter month of July of the following year, when the mean THI was 93+/-3.1 (dry bulb temperature of 35.6-43.9 degrees C and relative humidity 95-35%). Holstein cows produced more (p <0.01) milk than AMZ and Jersey cows during the cooler months of the year and all the cows were dry during the hotter months from June until September. Heat stress increased (p<0.01) rectal temperature and respiratory rate in all three breeds. Heat stress had no effect on blood pH in Holstein and AMZ cows but lowered (p <0.01) blood pH from 7.42 to 7.34 in Jersey cows. In addition, heat stress lowered (p <0.01) blood pCO2 (kPa), bicarbonate (HCO3, mmol/L), base excess (BE, mmol/L) and plasma chloride (Cl-, mmol/L) in all three breeds. The total haemoglobin (THb, g/dl) was elevated (p <0.01) in all three breeds when they were subjected to heat stress. Heat stress increased (p<0.01) oxygen saturation (O2SAT, %) in Jersey and AMZ cows but lowered it (p <0.01) in Holstein cows. On the other hand, heat stress increased (p <0.01)pO2 (kPa) in Holstein and Jersey cows but lowered it (p <0.01) in AMZ cows. Heat stress increased (p <0.01) plasma potassium (K, mmol/L) and calcium (Ca, mmol/L) only in Holstein and Jersey cows but lowered them (p<0.01) in AMZ cows. The plasma glucose (GLU, mmol/L) increased (p<0.01) with heat stress in Holstein and AMZ cows but decreased (p <0.01) in Jersey cows. Heat stress increased (p<0.01) plasma creatinine (CR, (mol/L) but lowered (p<0.01) plasma creatinine phosphokinase (CPK, IU/L), aspartate aminotransferase (AST, IU/L) and blood urea nitrogen (BUN, mmol/L) in all three breeds. These results indicate that heat-stressed Holstein and AMZ cows were able to maintain their acid-base balance with a marginal change in their pH of 0.02 when their rectal temperatures increased by 0.47 and 0.38 degrees C, respectively. When heat stress increased the rectal temperature in Jersey cows by 0.70 degrees C, the pH decreased (p<0.01) from 7.42 to 7.34. However, even with this decrease 0.08 the pH is still within the lower physiological limit of 7.31.  相似文献   

16.
非生长季土壤呼吸是生态系统碳循环的重要组成部分,显著地影响着碳收支。本研究利用Li-8100开路式碳通量测定系统,研究了青海湖北岸高寒草甸草原非生长季土壤呼吸对短期围栏封育(自由放牧,3年围栏封育和5年围栏封育样地)的响应,并讨论了温度和湿度对非生长季土壤呼吸的影响。结果表明,1)自由放牧、3年围栏封育和5年围栏封育样地非生长季土壤呼吸平均速率分别是全年土壤呼吸平均速率的0.21,0.22和0.19倍;2)自由放牧、3年围栏封育和5年围栏封育样地非生长季土壤呼吸所排放的碳量分别为117.2,109.2和100.7 g C/m2,占全年土壤呼吸所排放的碳量的21.2%,22.3%和23.2%;3)相比于生长季和全年土壤呼吸的温度敏感性,非生长季具有更低的土壤呼吸温度敏感性;4)非生长季土壤温度和土壤湿度对土壤呼吸的解释率相当,一定的土壤湿度是保证土壤呼吸对温度响应的必要条件。因此,当考虑到碳收支和生态系统碳循环时不能忽略掉非生长季土壤呼吸的作用,而且水分在调节非生长季土壤呼吸中起着重要的作用。  相似文献   

17.
用高温与常温两种温度进行一日两回育试验。调查蚕儿生长发育及饲料效率的差异。结果,高温区蚕儿生长快,叶丝转化率高;常温区生长发育较高温区慢,与四回育相同,但蚕茧质量优。  相似文献   

18.
We used an Atlantic grassland system on the Iberian Peninsula to ascertain whether monthly climate variability explains variation in monthly aboveground net primary production (ANPP) and to test whether climate-ANPP relationships depend on grazing regime. In 2005, large herbivores (beef cattle, dairy sheep, and horses) were excluded through fencing three 2 500-m2 plots, each located in a different location; adjacent grazed plots of equal size were established. ANPP was measured monthly during the next three growing periods (2006 ? 2008), and locally measured climate data were obtained from a public database. Because between-site variation in annual ANPP was not significant, we used data averaged across sites to test for the effect of monthly climate variability on monthly ANPP by means of dynamic regression. Enhanced ANPP was found after grazing abandonment, probably due to the sudden dominance of productive graminoids. Variation in monthly rainfall did not contribute to explain monthly ANPP under grazing or grazing exclusion. Simultaneous mean monthly air temperature explained monthly ANPP under grazing. By contrast, the effect of temperature on ANPP under grazing exclusion was delayed by 1 mo. We suggest that this delay can be explained by the development of a thick organic layer (litter) that insulated the soil in the grazing exclusion plots. However, changes in floristic composition and, consequently, in phenology might also have contributed to the differential response.  相似文献   

19.
乳中C18脂肪酸的同分异构体众多且含量差异较大,导致其测定分析时分离难度较大,影响后续的鉴定和定量。为了实现乳样中C18脂肪酸的良好分离,试验比较研究了3种温度程序(175℃和150℃升温程序、170℃等温程序)和3种样品浓度(提取原液、2倍稀释液、5倍稀释液)对乳样中C18脂肪酸分离效果的影响。结果表明:(1)色谱柱温度程序影响乳中C18:1脂肪酸的分离效果:就C18:1t6~C18:1t11的分离效果而言,150℃升温程序最好,175℃升温程序最差,且150℃升温程序可以分离出C18:1c15,170℃等温程序可以很好地分离开C18:1t12/13/14和C18:1t15,而175℃升温程序仅可分离出C18:1t12/13/14;(2)3种温度程序下C18:2 c9t12、C18:2t11c15与C19:0的出峰顺序不同:170℃等温程序中,C18:2c9t12和C18:2t11c15在C19:0之后出峰,而150℃升温程序时则在C19:0之前,175℃升温程序时C19:0在两种C18:2脂肪酸之间出峰;(3)样品浓度影响乳中C18脂肪酸的分离效果:在3种温度程序下2倍稀释浓度和5倍稀释浓度均可以提高C18:1t6至C18:1t11的分离效果,且150℃升温程序下5倍稀释还可以分离出C18:1t12/13/14,但5倍稀释会造成C18:1t5、C18:2t11c15浓度过低,峰高接近基线或无法检测。综上所述,色谱柱的温度程序不仅影响乳样中C18脂肪酸的分离效果,也影响脂肪酸的出峰顺序,而样品浓度主要影响C18脂肪酸的分离效果。实际分析中,采用该研究所示提取法的2倍稀释样品、并根据试验目的采用多种温度程序相结合的方法,可实现C18脂肪酸的理想分离。  相似文献   

20.
全球降水格局的改变势必会影响陆地生态系统的各项功能,而草地碳汇功能对水分的变化极为敏感.为探究不同降水梯度对生态系统碳交换产生的影响,于内蒙古四子王旗荒漠草原设置模拟降水试验(减水50%、自然降水、增水50%和增水100%),在2017年5月至9月,每隔15?d采用Li-6400便携式光合仪和密闭式箱法测定生态系统净碳...  相似文献   

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