科尔沁牛春季的牧食行为

2002年春季在内蒙古科左后旗的天然草场上,采用跟群放牧全日观察法,定量研究了自然放牧状态下成年科尔沁牛牧食行为.结果表明,科尔沁牛的平均采食时间为511.36±222.07min,反刍时间为66.38±14.60min,卧息时间为46.50±42.97min,站立时间为10.75±7.98min,游走时间为58.10±20.13min.平均采食速度为62.00±13.04口/分,平均采食量为10.38千克/头·天.对苔草草甸进行的受控放牧试验表明,主要牧草的选择性采食顺序为香茅＞蒲公英＞马蔺＞芦苇＞苔草.     

科尔沁牛夏季牧食行为的研究

2002年夏季在内蒙古科左后旗的天然草场上,采用跟群放牧全日观察法,定量研究了自然放牧状态下成年科尔沁牛牧食行为.结果表明,科尔沁牛的平均采食时间为410.9±34.8 min,反刍时间为4.2±8.2 min,卧息时间为5.0±17.3 min,站立时间为18.0±16.8 min,游走时间为80.4±12.9 min.平均采食量为8.10 千克/头*天.选择采食性特征最明显的7、8月份进行的调查结果表明,放牧牛采食所涉及的牧草种类共有16种,其中7月份11种,8月份12种.     

科尔沁牛夏季牧食行为的研究

2002年夏季在内蒙古科左后旗的天然草场上,采用跟群放牧全日观察法,定量研究了自然放牧状态下成年科尔沁牛牧食行为。结果表明,科尔沁牛的平均采食时间为410.9±34.8min,反刍时间为4.2±8.2min,卧息时间为5.0±17.3min,站立时间为18.0±16.8min,游走时间为80.4±12.9min。平均采食量为8.10千克/头·天。选择采食性特征最明显的7、8月份进行的调查结果表明,放牧牛采食所涉及的牧草种类共有16种,其中7月份11种,8月份12种。     

科尔沁牛冬季牧食行为

2002年冬季在内蒙古科左后旗的天然草场上,采用跟群放牧全日观察法,定量研究了科尔沁牛牧食行为.结果表明,科尔沁牛的平均采食时间为302.2±26.6 min,反刍时间为13.5±22.4 min,卧息时间为21.6±27.8 min,站立时间为14.1±9.5 min,游走时间为78.2±26.6 min.平均采食速度为47.9±15.7口/分钟,平均采食量为5.31千克/头·天.日反刍周期出现于午休时间,反刍行为主要在夜间进行,夜间的反刍时间、反刍周期数和反刍总食团数均增加.     

科尔沁牛冬季牧食行为

2002年冬季在内蒙古科左后旗的天然草场上,采用跟群放牧全日观察法,定量研究了科尔沁牛牧食行为。结果表明,科尔沁牛的平均采食时间为302．2±26．6 min,反刍时间为13．5±22．4 min,卧息时间为21．6±27．8 min,站立时间为14．1±9．5 min,游走时间为 78．2±26．6 min。平均采食速度为47．9±15．7口/分钟,平均采食量为5．31千克/头·天。日反刍周期出现于午休时间,反刍行为主要在夜间进行,夜间的反刍时间、反刍周期数和反刍总食团数均增加。     

蒙古牛春季牧食习性的观察研究

1997年春季(5月中下旬)在内蒙古锡林郭勒盟多伦县测定了蒙古牛的牧食习性,研究了蒙古牛的采食、站立、游走、卧息、反刍、饮水和排泄行为.研究结果表明,蒙古牛的平均采食时间为508.1±55.5min,共计6.3±2.1个采食周期;反刍时间为386.8±54.6min;卧息时间244.9±61.0min;站立游走时间300.2±79.0.平均采食速度7.6±8.1口/min,平均采食量10.10kg/头·d.蒙古牛春季采食的牧草种类主要为单子叶植物中的禾本科、莎草科、百合科和鸢尾科植物.     

雷州山羊春季牧食行为的观测

对雷州山羊春季牧食行为进行 2 4 h的连续观测表明 ,雷州山羊昼夜采食时间为 41 5 .37± 2 6.81 min,放牧平均采食速度 35 .34± 3.5 2口 /min,游走时间 1 5 .65± 7.32 min;每日饮水 3次 ,每次饮水量 0 .83± 0 .31 kg;昼夜反刍时间 375 .7± 2 1 .73min,反刍与采食时间之比为 0 .91∶ 1 ,昼夜反刍周期数 9.0 1± 0 .38,反刍周期持续时间 42 .1 9± 6.74min,每个食团咀嚼时间 5 0 .2 9± 8.42 s,反刍咀嚼速度 1 .35± 0 .1 5次 /s,夜间反刍时间占昼夜总反刍时间的 75 .66% ;昼夜排粪排尿次数分别为 8.67± 1 .37和 6.88± 1 .0 4 ,且白昼显著多于夜间 ( P<0 .0 5 )。     

雷州山羊春季牧食行为的观测

对雷州山羊春季牧食行为进行24 h的连续观测表明,雷州山羊昼夜采食时间为415.37±26.81 min,放牧平均采食速度35.34±3.52 口/min,游走时间15.65±7.32 min;每日饮水3次,每次饮水量0.83±0.31 kg;昼夜反刍时间375.7±21.73 min,反刍与采食时间之比为0.911,昼夜反刍周期数9.01±0.38,反刍周期持续时间42.19±6.74 min,每个食团咀嚼时间50.29±8.42s,反刍咀嚼速度1.35±0.15次/s,夜间反刍时间占昼夜总反刍时间的75.66%;昼夜排粪排尿次数分别为8.67±1.37和6.88±1.04,且白昼显著多于夜间(P＜0.05).     

科尔沁草地不同放牧制度牧食行为研究

2006年7~10月在科尔沁草地研究了不同放牧制度下科尔沁牛的牧食行为。结果表明:科尔沁牛的采食选择性很强,不仅表现在牧草的种类上,还表现在牧草的生长季节上,主要选择那些易消化的植物种类或部位,在两种放牧制度的食谱中狗尾草所占的比例均高于45%。植物种群采食后的平均留茬高度在不同放牧制度和不同月份具有不同的表现,轮牧条件下表现为10月份7月份8月份9月份;自由放牧条件下表现为10月份9月份8月份7月份。不同放牧制度下的采食速率、采食习性、排泄行为不同,轮牧条件下采食时间和采食路线短,采食速率和采食量高,反刍?卧息和站立时间均较长,排粪和排尿次数少。     

荷斯坦牛采食时间的群体特征及其影响因素分析

【目的】探究荷斯坦牛采食时间的群体规律及其影响因素,旨在为日采食时间的遗传分析奠定基础,同时为牧场利用采食时间对牛群进行精准管理提供参考。【方法】收集北京地区某规模化牧场2019年7月至2021年3月的1 166头泌乳期荷斯坦牛的原始采食时间记录(每小时记录1次)及日采食时间数据(每24 h记录1次),利用SAS 9.2线性混合模型分析胎次、测定季节、泌乳阶段、场区和测定年份对日采食时间的影响。【结果】北京地区荷斯坦牛日平均采食时间为(224.43±60.24) min,原始采食时间平均值为(9.41±4.67)min/h。根据原始采食时间统计分析发现,采食高峰均出现在投料时段,并且胎次、季节和泌乳阶段均对采食时间高峰存在一定影响。试验期间荷斯坦牛日采食时间随环境温湿度指数(temperature and humidity index, THI)的升高总体呈下降趋势,在夏季相对较低。胎次、测定季节、泌乳阶段、场区和测定年份均对日采食时间有极显著影响(P<0.01):日采食时间在春季最高,为(201.66±1.91) min,夏季最低,为(158.85±1.92) min;对于不同...     

Phase I evaluation of CCNU (lomustine) in tumor-bearing cats

1-(2-Chloroethyl)3-cyclohexyl-1-nitrosourea (CCNU) is an alkylating agent in the nitrosourea subclass. A prospective evaluation of CCNU was done to determine the maximally tolerated dosage of CCNU in tumor-bearing cats. Response data were obtained when available. Twenty-five cats were treated with CCNU at a dosage of 50-60 mg/m3 body surface area. Complete hematologic data were available for 13 cats. Neutropenia was the acute dose-limiting toxicity. The median neutrophil count at the nadir was 1,000 cells/microL (mean, 2,433 cells/microL; range, 0-9,694 cells/microL). The time of neutrophil nadir was variable, occurring 7-28 days after treatment, and counts sometimes did not return to normal for up to 14 days after the nadir. Based on these findings, a 6-week dosing interval and weekly hematologic monitoring after the 1st treatment with CCNU are recommended. The nadir of the platelet count may occur 14-21 days after treatment. The median platelet count at the nadir was 43,500 cells/microL. No gastrointestinal, renal, or hepatic toxicities were observed after a single CCNU treatment, and additional studies to evaluate the potential for cumulative toxicity should be performed. Five cats with lymphoma and 1 cat with mast cell tumor had measurable responses to CCNU. Phase II studies to evaluate antitumor activity should be completed with a dosing regimen of 50-60 mg/m3 every 6 weeks.     

Furosemide continuous rate infusion in the horse: evaluation of enhanced efficacy and reduced side effects

Continuous rate infusion (CRI) of furosemide in humans is considered superior to intermittent administration (IA). This study examined whether furosemide CRI, compared with IA, would increase diuretic efficacy with decreased fluid and electrolyte fluctuations and activation of the renin-angiotensin-aldosterone system (RAAS) in the horse. Five mares were used in a crossover-design study. During a 24-hour period, each horse received a total of 3 mg/kg furosemide by either CRI (0.12 mg/kg/h preceded by a loading dose of 0.12 mg/kg IV) or IA (1 mg/kg IV q8h). There was not a statistically significant difference in urine volume over 24 hours between methods; however, urine volume was significantly greater after CRI compared with IA during the first 8 hours ([median 25th percentile, 75th percentile]: 9.6 L [8.9, 14.4] for CRI versus 5.9 L [5.3, 6.0] for IA). CRI produced a more uniform urine flow, decreased fluctuations in plasma volume, and suppressed renal concentrating ability throughout the infusion period. Potassium, Ca, and Cl excretion was greater during CRI than IA (1,133 mmol [1.110, 1,229] versus 764 mmol [709, 904], 102.7 mmol [96.0, 117.2] versus 73.3 mmol [65.0, 73.5], and 1,776 mmol [1,657, 2.378] versus 1,596 mmol [1,457, 1,767], respectively). Elimination half-lives of furosemide were 1.35 and 0.47 hours for CRI and IA, respectively. The area under the excretion rate curve was 1,285.7 and 184.2 mL x mg/mL for CRI and IA, respectively. Furosemide CRI (0.12 mg/kg/h) for 8 hours, preceded by a loading dose (0.12 mg/kg), is recommended when profound diuresis is needed acutely in horses.     

Prevalence of gastric lesions in racing Alaskan sled dogs

Human and equine athletes are reported to have a high prevalence of gastric disease, and anecdotal evidence suggests a similar phenomenon applies to racing sled dogs. To investigate the prevalence of gastric disease in racing sled dogs, we conducted 2 gastroscopy studies on dogs competing in the annual Iditarod Sled Dog Race. A pilot study of dogs that were either dropped from the 2000 Iditarod Sled Dog Race because of illness or that finished the race indicated that, approximately 5 days after competing, 10 of 28 dogs (35%) had endoscopic evidence of gastric ulceration, erosion, or hemorrhage. The next year, an endoscopic study of 73 dogs participating in the 2001 Iditarod race was performed in order to evaluate a larger population of dogs. Data from 70 of these dogs could be used; 34 (48.5%) had ulceration, erosion, gastric hemorrhage, or some combination of these findings. When this group of 70 dogs was compared retrospectively to a control group of 87 dogs presented to the Texas A&M University (TAMU) Veterinary Medical Teaching Hospital, the Iditarod sled dogs had a significantly higher prevalence (P = .049) of gastric lesions. These findings suggest that, similar to athletes of other species, elite canine athletes have an increased prevalence of gastric disease compared to the canine population at large.     

The Epidemiology of Gastrointestinal Nematodes of Dairy Cattle in Central Kenya

The epidemiology of H. placei and of other gastrointestinal nematodes in yearling dairy cattle was examined on two farms in Kiambu District, central Kenya during each of 13 one-month periods from April 1993 to April 1994. On each farm, 32 newly weaned dairy calves were given a single dose of albendazole and then placed on experimental pastures. Twelve of the animals were designated for bi-monthly slaughter (n = 2) and analysis of worm population characteristics and 20 were designated for blood and faecal collection and for weighing. Two parasite-free tracer calves were grazed alongside the weaner calves each month throughout the study period and were also slaughtered for analysis of worm populations. Faecal egg counts, haematological and serum pepsinogen determinations, herbage larval counts, and animal live weight changes were recorded monthly. The study revealed that Haemonchus placei, Trichostrongylus axei, Cooperia spp. and Oesophagostomum radiatum were responsible for parasitic gastroenteritis and that H. placei was the predominant nematode present in the young cattle on both farms. Faecal egg counts from resident cattle and necropsy worm counts revealed that pasture larval levels were directly related to the amount of rainfall. The total worm burdens in the animals were highest during the rainy season (March–June and October–December) and lowest during the dry seasons (July–September and January–February). The very low recovery of immature larvae of H. placei from the tracer calves indicated that arrested development is not a feature of the life cycle of this parasite in central Kenya. The maintenance of the parasite population depended on continuous cycling of infection between the host and the pasture. The agroclimatic conditions of the study area were such that, in general, favourable weather conditions for the development and survival of the free-living stages of gastrointestinal nematodes existed all year round.     

Diversity of Ectoparasites in Sheep Flocks in Sa~o Paulo,Brazil

The occurrence of ectoparasites in sheep flocks is frequently reported but seldom quantified. Sheep production used to be a predominantly family activity in the state of Sa~o Paulo (Brazil), but it began to become a commercial activity in the past decade. Thus, information about the ectoparasites existing in sheep flocks has become necessary. The present data were obtained by means of questionnaires sent to all sheep breeders belonging to the `Associaça~o Paulista de Criadores de Ovinos' (ASPACO; Sa~o Paulo State Association of Sheep Breeders). Response reliability was tested by means of random visits paid to 10.6% of the respondents. Most of the properties (89.5%) reported the presence of one or more ectoparasites. Screw-worm (Cochliomyia hominivorax) was the most frequent ectoparasite (72.5%), followed by bot fly larvae (Dermatobia hominis, 45.0%), ticks (Amblyomma cajennense) and Boophilus microplus, 31.3%) and finally lice (Damalinia ovis, 13.8%). Combined infestations also occurred, the most common one being screw-worm with bot fly larvae (36.0%) followed by bot fly larvae with ticks (13.9%), screw-worm with ticks (9.3%), bot fly larvae with lice (6.9%), and ticks with lice (5.0%). The most common triple combination was screw-worm, bot fly larvae and ticks (12.8%). Breeds raised for meat or wool were attacked by bot fly larvae and ticks more often than other breeds. Lice were only absent from animals of indigenous breeds. The relationships among these ectoparasites are discussed in terms of sheep breeds, flock size, seasonality and the ectoparasitic combinations on the host.     

Evaluation of biohydrogenation rate of canola vs. soya bean seeds as unsaturated fatty acids sources for ruminants in situ

An experiment was conducted to study disappearance of C14 to C18 fatty acids, lag times and biohydrogenation (BH) rates of C18 fatty acids of ground soya bean and canola seeds in situ. Three ruminally fistulated Dallagh sheep were used to determine ruminal BH of unsaturated fatty acids (UFAs). Differences in the disappearance of fatty acids through the bags and lag times were observed between the oilseeds. We saw that the longer the incubation time of the oilseeds in the rumen, the lower the content of C18:2 and C18:3. Significantly higher lag times for both C18:2 and C18:3 were observed in ground canola compared to ground soya bean. BH rates of C18:2 and C18:3 fatty acids in soya bean were three times higher than those of canola. These results suggest that the fatty acid profile of fat source can affect the BH of UFAs by rumen micro‐organisms. So that UFAs of canola had higher ability to escape from ruminal BH. It seems that fatty acid profile of ruminant products is more affected by canola seed compared to soya bean seed.     

Serum biochemical values and mineral element contents of tissues in yaks

Serum biochemical values and the wet weight to dry weight ratios of tissues were determined in yaks in Shandan county of Gansu province. The liver, kidney, heart and muscle contents of seven elements in yaks were also analysed. Most serum biochemical values were similar to those of cattle, camels and sheep, but the calcium concentration was considerably above the normal range for other ruminants. The liver contained the highest concentrations of copper, manganese and cobalt and the kidney of selenium, iron and calcium.Abbreviations Alb albumin - ALT alanine aminotransferase - AST aspartate aminotransferase - BUN blood urea nitrogen - Chol cholesterol - Glob globulin - -GT -glutamyl transpeptidase - IP inorganic phosphorus - TP total protein     

Avian brood parasitism — a growing research area in behavioral ecology (part Ⅱ)

正We are pleased to publish the second special issue on avian brood parasitism and to be responsible guest editors for the two special issues of Chinese Birds (Vol. 3, No. 4, 2012 and Vol. 4, No. 1, 2013), entitled "Avian Brood Parasitism - A Growing Research Area in Behavioral Ecology". The first issue was published in December 2012. The goal of the two special issues is to publish accumulated knowledge and some of the recent developments in     

Internal Parasites and Haematological Values in Cattle Slaughtered in Buea Subdivision of Cameroon

Tropical Animal Health and Production -