Variability in vocal and behavioural responses to visual isolation between full-sibling families of beef calves

In order to assess the value of vocal response as an indicator of welfare in cattle, it is necessary to investigate factors which influence vocal behaviour of individuals, that are independent of the specific environmental conditions to which they are exposed. The effect of parental differences, sex, age and weight on vocal responses of calves to visual isolation were examined. The relationship between vocal response and the amount of body movement during isolation were also evaluated.

Seventeen full-sibling families of beef calves (N=130) were created by breeding five sires with 13 superovulated dams. Embryos were transferred into unrelated cows, which reared the calves to weaning age. Vocal response of calves and body movement were measured on four occasions, while they were visually isolated for 1 min on a single animal scale platform. The first two observations were made on the day of weaning (mean age 166 days) and the following day. At the third and fourth observations their average ages were 278 and 350 days, respectively. On the four occasions 33.3, 34.8, 27.8 and 38.6% of calves, respectively, vocalized. Both sire and family had a significant influence on the number of vocalizations and acoustic properties of the sounds. Electronically-measured movement while on the scale was also influenced by sire and family, but there was no relationship between vocal responses and body movement. There was a tendency (P=0.08) for older and therefore heavier calves to produce longer vocalizations. In the final observing session, age and weight were positively correlated with fundamental frequency and the sound pressure level at the frequency of greatest intensity, and negatively correlated with the loudest harmonic. At the last two observations, significantly more heifer calves than bull calves vocalized. There was little difference between the acoustic properties of heifers’ and bulls’ vocalizations.

The considerable individual variability in vocal response within a group of identically-treated calves is partly due to parental genetic influences that are independent of rearing and early experience. Other endogenous characteristics such as sex, age and weight also influence vocal response. But there is no clear relationship between individual temperament (as assessed by the amount of body movement during isolation) and characteristics of vocal response.     

Weaning distress in dairy calves: Effects of alternative weaning procedures

The aims of this study were to describe the behavioural responses to weaning from milk in dairy calves, and to compare responses when calves were either weaned abruptly (removal of the milk-feeding system; n = 8 calves) or by substituting warm water for milk in the milk-feeding apparatus for the first 2 days after weaning (n = 8 calves). Calves provided water through the milk-feeding system after weaning seemed to substitute one liquid for the other; calves consumed approximately the same quantity of warm water after weaning (8 kg/day) as they had consumed milk before weaning (9 kg/day). All calves vocalized at weaning, but abruptly weaned calves vocalized at more than three times the rate of calves provided water through the milk-feeding system. On the third day after weaning, when neither treatment group had access to the milk-feeding system, the call rate was similar in the two treatment groups. The abruptly weaned calves were also more active at weaning, as indicated by an increased number of standing bouts compared to calves with continued access to the milk-feeding apparatus. The reduced response to weaning by the calves with continued access to the feeding routine may be due to the gut fill associated with the water intake or to other rewarding properties of the system (e.g. allowing calves to suck on a teat). In conclusion, dairy calves show a strong behavioural response to weaning, but providing calves continued access to the milk-feeding apparatus for 2 days after weaning reduces this response.     

Body temperature of ostriches (Struthio camelus) kept in an open stable during winter time in Germany

Commercial breeding of ostriches in the northern parts of Europe is still discussed controversially in particular in winter. Here we measured the body temperature of 12 ostriches of two different ages during 12 weeks in winter using temperature loggers implanted subcutaneously and in the abdominal cavity. The mean peritoneal temperature ranged between 37.4 and 38.5 °C in the younger subjects and between 37.2 and 38.1 °C in the older subjects. Climatic conditions significantly affected the body temperature but in comparison with the variations between and within subjects these effects were low. There was no evidence that the young ostriches were not able to adapt towards the climatic conditions prevalent during our study.     

心房颤动模型中实验动物优化的研究进展

房颤动物模型的建立对于研究房颤的机制以及治疗方法有着极其重要的作用。而房颤医学模型需要较长时间才能获得,对实验动物有一定的特殊要求,并且影响较大。这样,实验动物优化,即实验动物福利的改良与发展就显得重要,是促进建模成功的重要保障。我们从伦理与法规支持,饲养管理,替代方法和福利技术四个方面综述心房颤动医学模型中实验动物福利的改良与发展。     

动物存活率与平均寿命的数学关系

根据动物存活率与平均寿命的定义,推导出存活率与平均寿命的数学关系,即：E=-1lnr,其中E表示动物的平均寿命或期望寿命(可以用日、周、月、年等表示),r表示特定时段内(可以用日、周、月、年等表示)动物的平均存活率,其时间单位与E相对应．根据这种关系,可以利用动物的平均存活率估计其平均寿命(或期望寿命),反之,如果已知动物的平均寿命,也可以用来推算动物的平均存活率．     

Age,sex, and antemortem loss of teeth in prehistoric Eskimo samples from point hope and Kodiak Island,Alaska

The incidence of teeth lost antemortem was investigated in 244 archeologically derived dried skeletal specimens from the Ipiutak and Tigara burials at Point Hope, Alaska, and 83 Koniag Eskimo specimens excavated at Jones Point, Uyak Bay, Kodiak Island, Alaska. Ipiutak skeletal remains date from approximately 1500 years B.P. and the Tigara remains from 300–400 years B.P. The Kodiak Island sample is undated. Specimens were sexed and aged in five-year groupings using standard techniques. Teeth lost antermortem were identified as having occupied tooth sockets which showed healing of alveolar bone following exfoliation. Numbers of lost teeth were calculated as percentages of total number of tooth sites of each tooth classification for each age, sex, and site subgrouping. Tooth loss was very low in the Kodiak Island sample, with little difference between sexes and no identifiable age trends. The Tigara ramains displayed moderate tooth loss, with strong correlations to increasing age and little differentiation between the sexes. The Ipiutak specimens lost the most teeth antemortem, with notable between-sex differences and strong correlations with increasing age. In all groups loss of anterior teeth was probably due to accident or heavy wear, while loss of posterior teeth was due to heavy wear, periodontal disease, or agenesis.     

药物安全性评价中的实验动物福利

开展实验动物福利工作不论对于实验动物自身,还是科学研究都具有重要意义。本文对实践中如何开展实验动物福利工作,以及其中存在的问题进行了初步探讨。     

动物福利在研究生实验动物学教学中的应用初探

在医学研究中,实验动物具有不可替代的地位和作用,越来越多的人开始关心动物福利。各医学院校是培养未来科研工作者的机构,实验动物在医学院校的使用量非常大,因此,在课堂教学中,培养医学生树立保护动物福利的观念具有重要意义。本文从课堂教育、实验动物处理、3R原则的实施等方面探讨了如何在教学过程中开展动物福利教育。     

ABA诱导基因及其与逆境胁迫的关系(综述)

本文介绍 ABA 诱导基因的类型、结构、功能,并对其表达与逆境胁迫的关系进行综述。     

安徽省家畜分布与土地利用类型关系的研究

本文采用灰色系统理论与方法,研究了安徽省及其各畜牧区的家畜(禽)分布随土地利用类型及人口密度的变化规律,建立了家畜(禽)分布密度的灰色静动态模型。结果表明,安徽省由北向南旱地面积从54％下降到2％;林地则由5.5％上升到62％;水田和水面主要分布在江淮丘陵和沿江平原区。人口密度对各类畜禽的分布密度有较大的影响,关联度为0.65—0.83;旱地比率是影响草食动物分布密度的最主要因素,并联度高达0.9以上;水面的比重对家禽密度的影响高于其它因子。用土地利用类型因子及人口密度所建立的模型,对家畜的实际分布密度及其变化规律的拟合误差在2％左右。     

A review of pain assessment techniques and pharmacological approaches to pain relief after bovine castration: Practical implications for cattle production within the United States

Castration of male calves destined for beef production is a common livestock management practice in the United States amounting to approximately 7 million procedures per year. Recently there has been renewed interest in identifying methods to reduce pain associated with dehorning and castration. Although several studies have reported that analgesic drug administration prior to castration attenuates plasma cortisol response, there are currently no compounds specifically approved for pain relief in livestock in the U.S. Validated pain assessment tools are needed to support regulatory approval of analgesic compounds. This may include use of accelerometers, videography, heart rate variability determination, electroencephalography, thermography and plasma neuropeptide measurement to assess behavioral, physiological and neuroendocrine changes associated with a pain response. Extra-label drug use (ELDU) for pain relief is regulated under the Animal Medicinal Drug Use Clarification Act (AMDUCA) and requires that drugs be administered by or under the supervision of a veterinarian. Agents that may provide preemptive analgesia include local anesthetics, nonsteroidal anti-inflammatory drugs (NSAIDs), opioids, α2-agonists, and N-methyl d-aspartate (NMDA) receptor antagonists. A review of the published literature suggests that a significant decrease in plasma cortisol concentration after castration was associated with preemptive administration of a NSAID and local anesthesia. Local anesthesia alone tended to decrease peak plasma cortisol concentrations more than NSAIDs. However NSAIDs alone tended to decrease the area under the plasma cortisol-time curve more than local anesthesia alone. These findings suggest that multimodal analgesic regimens that extend into the post-operative period are more effective at mitigating pain and distress associated with castration than a single drug modality. Regulatory approval of safe and cost effective analgesic compounds with convenient routes of administration is needed for routine use of pain relieving drugs to be considered as standard practice at the time of castration.     

Positive Reinforcement Training for Blood Collection in Grizzly Bears (Ursus arctos horribilis) Results in Undetectable Elevations in Serum Cortisol Levels: A Preliminary Investigation

Training nonhuman animals in captivity for participation in routine husbandry procedures is believed to produce a lower stress environment compared with undergoing a general anesthetic event for the same procedure. This hypothesis rests largely on anecdotal evidence that the captive subjects appear more relaxed with the trained event. Blood markers of physiological stress responses were evaluated in 4 captive grizzly bears (Ursus arctos horribilis) who were clicker-trained for blood collection versus 4 bears who were chemically immobilized for blood collection. Serum cortisol and immunoglobulin A (IgA) and plasma β-endorphin were measured as indicators of responses to stress. Plasma β-endorphin was not different between the groups. Serum IgA was undetectable in all bears. Serum cortisol was undetectable in all trained bears, whereas chemically immobilized bears had marked cortisol elevations (p < .05). The highest cortisol elevations were found in 2 bears with extensive recent immobilization experience. These findings support the use of positive reinforcement training for routine health procedures to minimize anxiety.     

Relationship between sex ratio and time of insemination according to both time of ovulation and maturational state of oocyte

The aim of this study was to explore how some reproductive methodologies may affect the sex ratio. We first confirmed the association between the maturation stage of bovine oocytes at the time of in vitro fertilisation (IVF) and the sex ratio of in vitro-derived embryos. Secondly, we studied whether the time of insemination, prior to or after ovulation, could alter the sex ratio in sheep. In the first experiment, bovine oocytes were matured in vitro for 16 h; then oocytes were either fertilised in vitro immediately after extrusion of the first polar body or IVF was delayed for 8 h. The proportion of cleaving embryos and their development to the 8-cell stage was enhanced with delayed insemination. Moreover, delaying IVF produced a male-to-female sex ratio of 1.67:1.00, which was significantly different from the expected 1:1 ratio (p < 0.05), whereas more female embryos were produced when oocytes were fertilised in vitro immediately after polar body extrusion (sex ratio of 1.00:0.67; p < 0.05). In the second experiment, 380 ewes were inseminated at different times before or after ovulation, producing 537 lambs. Significant differences in the sex ratio were obtained when we compared the sex of the offspring of ewes inseminated during the 5 h preceding ovulation (more females) with those inseminated during the 5 h after ovulation (more males). Our results suggest that the differential ability of X- or Y-bearing spermatozoa to fertilise oocytes depending either on time of insemination or oocyte maturation state, may be due, at least partially, to 'intrinsic' differences in the physiological activity of X- or Y-bearing spermatozoa before fertilisation.     

Livestock production system management responses to thermal challenges

The adaptive capabilities of animals and livestock production systems have been emphasized in this report. Biometeorology has a key role in rational management to meet the challenges of thermal environments. While the focus is primarily on cattle in warm or hot climates, the importance of dynamic animal responses to environmental challenges applies to all species and climates. Methods used to mitigate environmental challenges focus on heat loss/heat production balance. Under cold stress, reduction of heat loss is the key. Under heat stress, reduction of heat load or increasing heat loss are the primary management tools, although heat-tolerant animals are also available. In general, livestock with health problems and the most productive animals (e.g., highest growth rate or milk production) are at greatest risk of heat stress, thereby requiring the most attention. Risk management, by considering perceived thermal challenges, then assessing the potential consequences and acting accordingly, will reduce the impact of such challenges. Appropriate actions include: shade, sprinkling, air movement, or active cooling. Summarizing, the most important element of proactive environmental management to reduce risk is preparation: be informed, develop a strategic plan, observe and recognize animals in distress, and take appropriate tactical action.     

Social order and energy consumption in matrifocal households

The positive association between energy used and social complexity proposed by Leslie White and his students is examined at the microsociological level of the household. The hypothesis is tested within matrifocal households supported either by welfare or by the mother's earnings. White's macrosociological proposition is found to be conditional on other cultural, social organizational factors. Household energy consumption rises to the extent that the family establishes ties with outside social organizations, with an increase in the tempo of household activity, and, pari passu,with the expressiveness of the personality of the female household head. Energy consumption is a way of coping with the effects of reduced social organizational and personality order. These social factors interact with demographic and technological factors in determining a social organization's level of energy consumption. By considering the institutional, organizational, and motivational measures suggested in this paper, the unreliability of energy use predictions may be reduced.This is part of a larger study of Paternal Authority and the Outcome of Work Training and Income Maintenance Programs supported by the Grant 51-42-73-05/21-42-74-31 by the Employment and Training Administration of the U.S. Department of Labor to the Center for Research on the Acts of Man, Philadelphia. The author, not the Department, is responsible for the assertions herein. For assistance in the preparation of these materials the author is indebted to Albert J. Kostelny, Jr., Joseph R. Piasecki, the Institute for Survey Research at Temple University, and the Energy Center of the University of Pennsylvania.     

Cortisol and behavioral responses to enrichment in military working dogs

Our objective was to compare the effects of two schedules of enrichment exposure, a distributed (high frequency) and regular regime versus a mass (low frequency) and irregular regime, on the cortisol and behavioral responses of 14 kennelled military working dogs. The enrichment experiences were exercise coupled with human contact. Both groups of dogs were exposed to approximately the same total amount of enrichment per week for a total of 7 weeks. The distributed and regular regime (DRR) furnished enrichment for 20-min intervals three to four times a day every weekday; the mass and irregular regime (MIR) randomly furnished enrichment for 16 or 24 continuous hours 1 day out of 5. Our data show that: (1) cortisol concentrations of DRR dogs significantly decreased between the first and the last week of observations; this was not the case in MIR dogs; (2) at the 7th week DRR dogs had lower cortisol concentrations than did MIR dogs; (3) all dogs in each group exhibited stereotypies. Our results suggest that MIR dogs underwent a decline in welfare throughout the experiment, whereas DRR dogs appeared to undergo a period of acute stress at the beginning of their training that resolved over 7 weeks. This study suggests that the welfare of kennelled dogs, particularly military working dogs, is affected among other factors by schedules of exercise and contact with people.     

Relationship between push phase and final race time in skeleton performance

The aim of this study was to examine the relationship between push-time and final race time in skeleton participants during a series of major international competitions to determine the importance of the push phase in skeleton performance. Correlations were computed from the first and second heat split data measured during 24 men and 24 women skeleton competitions. Body mass, height, age, and years of experience of the first 30 men and women athletes of the skeleton, bobsleigh and luge 2003-2004 World Cup ranking were used for the comparison between sliding sports. Moderate but significant correlations (p < 0.05) were found between push-time and final race time in men (r(mean) = 0.48) and women (r(mean) = 0.63). No correlations were found between changes in the individual push-time between the first and second heat with the corresponding changes in final race time. The bobsleigh sliders are heavier than the athletes of the other sliding disciplines. Luge athletes have more experience and are younger than bobsleigh and skeleton sliders. The results of this study suggest that a fast push phase is a prerequisite to success in competition and confirms that the selection of skeleton athletes based on the ability to accelerate to a maximum speed quickly could be valid. However, a good or improved push-time does not ensure a placement in the top finishing positions. On the basis of these results, we suggest that strength and power training is necessary to maintain a short push-time but additional physical training aimed to enhance the push phase might not reflect performance improvements. The recruitment of younger athletes and an increase of youthful competitive activity may be another effective way to reach international competitive results.     

Improved tenderness of beef from bulls supplemented with active dry yeast is related to matrix metalloproteinases and reduced oxidative stress

Supplementing diets with active dry yeast (ADY, Saccharomyces cerevisiae) improves the carcass quality grade of beef cattle and the tenderness of beef. The relevant mechanisms have not been fully elucidated, but may be related to the effect of ADY on oxidative stress and the activity of matrix metalloproteinases (MMPs). To provide further insight into these mechanisms, this study evaluated the influence of ADY supplementation on growth performance, carcass traits, meat quality, concentrations of MMPs in serum (MMP-2, MMP-9 and MMP-13), oxidative stress indices and antioxidant capacity indices in beef cattle. Forty-six crossbred Simmental × Yanbian bulls (～18 months of age, BW 436 ± 35 kg) participated in a 145-day finishing trial. ADY supplementation significantly improved marbling deposition, intramuscular fat content, and beef tenderness (P < 0.05); altered individual fatty acid proportions in the beef and increased saturated fatty acids while decreasing polyunsaturated fatty acids (P < 0.05); significantly decreased the abundance of reactive oxygen species in serum and meat; significantly increased the level of superoxide dismutase in meat (P < 0.05); tended to increase the level of catalase (P = 0.075) in serum and glutathione reductase (P = 0.066) in meat; and increased the secretion of MMPs. The improvement of beef tenderness following ADY supplementation of finishing bulls is related to the effects of ADY on the secretion of MMPs and the lowering of oxidative stress.