Factors of domestic behavior variation in farm animals species

Fear response and domestic behavior of sheep, cattle, horses, and pigs were studied using four different variants of experimental stress conditions. As standard aversive stimulus, the factor of human presence during the feeding time was used under the following conditions: animals were starved for 12-14 or 2 h before the exposure and fed individually or in a group. In the animal species studied, these conditions were found to reveal phenotypic and genotypic differences in fear response to humans, which is correlated with feeding behavior by regulatory mechanisms. A comparative qualitative and quantitative study of the discrete variation of the associated passive-defensive responses and feeding behavior (as related to domestic behavior) was conducted with regard to the effect of the breed and individual genotypes and the feeding and zoosocial deprivation. A classification scheme of the individual diversity of this behavior in farm animal species is proposed, in which ontogenetic and evolutionary relationships earlier found in sheep were taken into consideration. It is suggested that the progressive ecological and zootechnical specialization alters adaptive reaction norms of stress response in breeds and leads to the formation of the homologous variation in a set of coadapted traits, i.e., constitutional types of animals genetically marked by their behavior. A conclusion is made that heritable polymorphism of domestic behavior represents a new source of adaptive variation for improving the total fitness, welfare, and productivity of farm animals by breeding.     

Domesticated behavior in sheep. Role of behavioral polymorphism in the regulation of stress reactions in sheep]

The relationship between behavioral polymorphism and the variation for the function of the hypothalamic-pituitary-adrenocortical axis (HPAA) was studied in the meat-and-wool (n = 447) and Altaian fine-fleece (n = 45) sheep breeds under production farm conditions. The behavior studied included negatively associated reactions: feeding reactions and defensive reactions in relation to human. In sheep, the intrapopulation variation for the stress level of corticosteroids depended on the effect of behavior, the type of stimulus, and the interaction between these two factors and correlated with the behavior phenotype (r varied from -0.551 to -0.226). In the stress responses to either 24-h starvation or lamb weaning, hormonal reactions were similar in wild-type sheep that have clearly marked defensive reactions and in the sheep of the domestic phenotype that was contrasted to the wild type. In the stress responses to isolation from the herd, transportation, and competition for food, hormonal reactions were stronger in the wild type than in the domestic phenotype; alternatively, in the stress response to being kept in cages in pairs, hormonal reaction was stronger in the domestic phenotype than in the wild type. In the sheep that were placed in cages, a single playing of tape-recorded anxiety signals caused the motivational or emotional stress that was characterized by an unusually long latent period of the progressive HPAA reaction and its subsequent chronic course (up to 9 days). Animals of contrasted behavioral phenotypes differed in the course of the HPAA reaction. Heritable behavioral polymorphism and interaction between behavior and the type of stimulus are the regulation factors in the expression and variability of stimulus-specific reactions of HPAA. Behavior can serve as the genetic marker for individual features of HPAA functioning in the stress response of sheep.     

Differences in mean retention time of sheep and goats under controlled feeding practices

The objective of this study was to compare the mean retention time (MRT): (a) between sheep and goats when they fed in groups with the same diet, the same amount of food and forage to concentrate (F/C) ratio and (b) between group and individual feeding in each animal specie (the same diet, the same amount of food and F/C ratio). Twelve, 3-4 years old, Friesian crossed dairy ewes and twelve, 3-5 years old, Alpine crossed dairy goats were used for the experiment. The animals were fed with a diet, consisted of alfalfa hay, wheat straw and concentrate, in two treatments. In Treatment A the animals fed on a group basis as it is traditionally used in practise, while in Treatment B the diet was offered individually toin each animal, in order to have fully comparable feeding level among animals and between treatments. Each Treatment (A and B) lasted 3 weeks. The results of this study have shown that: sheep had significantly longer rumen retention time (RRT) (30.03 vs. 14.43) and mean retention time (MRT) (40.80 vs. 27.81), and shorter transit time (TT) (8.86 vs. 11.49) than goats, while the caecum retention time (CRT) did not differ between the two species in Treatment A (group feeding). The comparison between group (Treatment A) and individual feeding (Treatment B) in goats or in sheep has shown that there were no significant differences as RRT, CRT, TT and MRT concerns. In conclusion, animal species (sheep vs. goat) was the main factor which affected the MRT, RRT and TT when the animals were fed in groups with the same diet, amount of food and F/C ratio, while the feeding technique (group vs. individual) had no effect on those parameters in both animal species.     

Group size elicits specific physiological response in herbivores

With increasing group size, individuals commonly spend less time standing head-up (scanning) and more time feeding. In small groups, a higher predation risk is likely to increase stress, which will be reflected by behavioural and endocrine responses. However, without any predator cues, we ask how the predation risk is actually processed by animals as group size decreases. We hypothesize that group size on its own acts as a stressor. We studied undisturbed groups of sheep under controlled pasture conditions, and measured in situ the cortisol and vigilance responses of identified individuals in groups ranging from 2 to 100 sheep. Both vigilance and average cortisol concentration decreased as group size increased. However, the cortisol response varied markedly among individuals in small groups, resulting in a lack of correlation between cortisol and vigilance responses. Further experiments are required to explore the mechanisms that underlie both the decay and the convergence of individual stress in larger groups, and whether these mechanisms promote adaptive anti-predator responses.     

Comparative assessment of human and farm animal faecal microbiota using real-time quantitative PCR

Pollution of the environment by human and animal faecal pollution affects the safety of shellfish, drinking water and recreational beaches. To pinpoint the origin of contaminations, it is essential to define the differences between human microbiota and that of farm animals. A strategy based on real-time quantitative PCR (qPCR) assays was therefore developed and applied to compare the composition of intestinal microbiota of these two groups. Primers were designed to quantify the 16S rRNA gene from dominant and subdominant bacterial groups. TaqMan^® probes were defined for the qPCR technique used for dominant microbiota. Human faecal microbiota was compared with that of farm animals using faecal samples collected from rabbits, goats, horses, pigs, sheep and cows. Three dominant bacterial groups ( Bacteroides/Prevotella, Clostridium coccoides and Bifidobacterium ) of the human microbiota showed differential population levels in animal species. The Clostridium leptum group showed the lowest differences among human and farm animal species. Human subdominant bacterial groups were highly variable in animal species. Partial least squares regression indicated that the human microbiota could be distinguished from all farm animals studied. This culture-independent comparative assessment of the faecal microbiota between humans and farm animals will prove useful in identifying biomarkers of human and animal faecal contaminations that can be applied to microbial source tracking methods.     

Retreat space and human visitor density moderate undesirable behavior in petting zoo animals

This study focused on the relationship between nonhuman animal behavior and environment-specifically, between the undesirable behavior exhibited by domestic petting zoo animals in the presence of humans and the spatial design of the petting zoo environment. A spatial feature of a petting zoo referred to as a retreat space was manipulated so that it affected the animals' opportunity for individual control over interaction with humans. Three conditions were tested: no retreat space, semi-retreat space, and a full-retreat space. The subjects of this study were 5 African pygmy goats (Capra hircus) and 2 Romanov sheep (Ovis aries). Investigators used a focal sampling technique to analyze approximately 27 hr of behavioral data collected. The data were analyzed using multiple linear regression methods. The findings suggest that the full-retreat design beneficially moderated both sheep and goat behavior: Undesirable behaviors were lowest in the full-retreat condition. This study provides information that may improve human-animal interactions in a petting zoo setting and may increase animal well-being through exhibit design and management techniques.     

Invited review: resource allocation mismatch as pathway to disproportionate growth in farm animals – prerequisite for a disturbed health

The availability of resources including energy, nutrients and (developmental) time has a crucial impact on productivity of farm animals. Availability of energy and nutrients depends on voluntary feed intake and intestinal digestive and absorptive capacity at optimal feeding conditions. Availability of time is provided by the management in animal production. According to the resource allocation theory, resources have to be allocated between maintenance, ontogenic growth, production and reproduction during lifetime. Priorities for these processes are mainly determined by the genetic background, the rearing system and the feeding regimen. Aim of this review was to re-discuss the impact of a proper resource allocation for a long and healthy life span in farm animals. Using the barrel model of resource allocation, resource fluxes were explained and were implemented to specific productive life conditions of different farm animal species, dairy cows, sows and poultry. Hypothetically, resource allocation mismatch neglecting maintenance is a central process, which might be associated with morphological constraints of extracellular matrix components; evidence for that was found in the literature. A potential consequence of this limitation is a phenomenon called disproportionate growth, which counteracts the genetically determined scaling rules for body and organ proportions and could have a strong impact on farm animal health and production.     

Retreat Space and Human Visitor Density Moderate Undesirable Behavior in Petting Zoo Animals

This study focused on the relationship between nonhuman animal behavior and environment-specifically, between the undesirable behavior exhibited by domestic petting zoo animals in the presence of humans and the spatial design of the petting zoo environment. A spatial feature of a petting zoo referred to as a retreat space was manipulated so that it affected the animals' opportunity for individual control over interaction with humans. Three conditions were tested: no retreat space, semi-retreat space, and a full-retreat space. The subjects of this study were 5 African pygmy goats (Capra hircus) and 2 Romanov sheep (Ovis aries). Investigators used a focal sampling technique to analyze approximately 27 hr of behavioral data collected. The data were analyzed using multiple linear regression methods. The findings suggest that the full-retreat design beneficially moderated both sheep and goat behavior: Undesirable behaviors were lowest in the full-retreat condition. This study provides information that may improve human-animal interactions in a petting zoo setting and may increase animal well-being through exhibit design and management techniques.     

Climate and weather impact timing of emergence of bats

Interest in forecasting impacts of climate change have heightened attention in recent decades to how animals respond to variation in climate and weather patterns. One difficulty in determining animal response to climate variation is lack of long-term datasets that record animal behaviors over decadal scales. We used radar observations from the national NEXRAD network of Doppler weather radars to measure how group behavior in a colonially-roosting bat species responded to annual variation in climate and daily variation in weather over the past 11 years. Brazilian free-tailed bats (Tadarida brasiliensis) form dense aggregations in cave roosts in Texas. These bats emerge from caves daily to forage at high altitudes, which makes them detectable with Doppler weather radars. Timing of emergence in bats is often viewed as an adaptive trade-off between emerging early and risking predation or increased competition and emerging late which restricts foraging opportunities. We used timing of emergence from five maternity colonies of Brazilian free-tailed bats in south-central Texas during the peak lactation period (15 June-15 July) to determine whether emergence behavior was associated with summer drought conditions and daily temperatures. Bats emerged significantly earlier during years with extreme drought conditions than during moist years. Bats emerged later on days with high surface temperatures in both dry and moist years, but there was no relationship between surface temperatures and timing of emergence in summers with normal moisture levels. We conclude that emergence behavior is a flexible animal response to climate and weather conditions and may be a useful indicator for monitoring animal response to long-term shifts in climate.     

Interspecies differences in the empty body chemical composition of domestic animals

Domestication of animals has resulted in phenotypic changes by means of natural and human-directed selection. Body composition is important for farm animals because it reflects the status of energy reserves. Thus, there is the possibility that farm animals as providers of food have been more affected by human-directed selection for body composition than laboratory animals. In this study, an analysis was conducted to determine what similarities and differences in body composition occur between farm and laboratory animals using literature data obtained from seven comparative slaughter studies (n = 136 observations). Farm animals from four species (cattle, goats, pigs and sheep) were all castrated males, whereas laboratory animals from three species (dogs, mice and rats) comprised males and/or females. All animals were fed ad libitum. The allometric equation, Y = aX^b, was used to determine the influence of species on the accretion rates of chemical components (Y, kg) relative to the growth of the empty body, fat-free empty body or protein weights (X, kg). There were differences between farm and laboratory animals in terms of the allometric growth coefficients for chemical components relative to the empty BW and fat-free empty BW (P < 0.01); farm animals had more rapid accretion rates of fat (P < 0.01) but laboratory animals had more rapid accretion rates of protein, water and ash (P < 0.01). In contrast, there was no difference in terms of the allometric growth coefficients for protein and water within farm animals (P > 0.2). The allometric growth coefficients for ash weight relative to protein weight for six species except sheep were not different from a value of 1 (P > 0.1), whereas that of sheep was smaller than 1 (P < 0.01). When compared at the same fat content of the empty body, the rate of change in water content (%) per unit change in fat content (%) was not different (P > 0.05) across farm animal species and similar ash-to-protein ratios were obtained except for dogs. The fraction of empty body energy gain retained as fat increased in a curvilinear manner, and there was little variation among farm animals at the same fat content of the empty body. These findings may provide the opportunity to develop a general model to predict empty body composition across farm animal species. In contrast, there were considerable differences of chemical body composition between farm and laboratory animals.     

Molecular approaches to aggregation behavior and social attachment

In many animal species individuals aggregate to live in groups. A range of experimental approaches in different animals, including studies of social feeding in nematodes, maternal behavior in rats and sheep, and pair-bonding in voles, are providing insights into the neural bases for these behaviors. These studies are delineating multiple neural circuits and gene networks in the brain that interact in ways that are as yet poorly understood to coordinate social behavior.     

How group size affects vigilance dynamics and time allocation patterns: the key role of imitation and tempo

In the context of social foraging, predator detection has been the subject of numerous studies, which acknowledge the adaptive response of the individual to the trade-off between feeding and vigilance. Typically, animals gain energy by increasing their feeding time and decreasing their vigilance effort with increasing group size, without increasing their risk of predation ('group size effect'). Research on the biological utility of vigilance has prevailed over considerations of the mechanistic rules that link individual decisions to group behavior. With sheep as a model species, we identified how the behaviors of conspecifics affect the individual decisions to switch activity. We highlight a simple mechanism whereby the group size effect on collective vigilance dynamics is shaped by two key features: the magnitude of social amplification and intrinsic differences between foraging and scanning bout durations. Our results highlight a positive correlation between the duration of scanning and foraging bouts at the level of the group. This finding reveals the existence of groups with high and low rates of transition between activities, suggesting individual variations in the transition rate, or 'tempo'. We present a mathematical model based on behavioral rules derived from experiments. Our theoretical predictions show that the system is robust in respect to variations in the propensity to imitate scanning and foraging, yet flexible in respect to differences in the duration of activity bouts. The model shows how individual decisions contribute to collective behavior patterns and how the group, in turn, facilitates individual-level adaptive responses.     

MicroRNAs in farm animals

MicroRNAs (miRNAs) are a class of ∼22 nucleotide-long small noncoding RNAs that target mRNAs for translational repression or degradation. miRNAs target mRNAs by base-pairing with the 3′-untranslated regions (3′-UTRs) of mRNAs. miRNAs are present in various species, from animals to plants. In this review, we summarize the identification, expression, and function of miRNAs in four important farm animal species: cattle, chicken, pig and sheep. In each of these species, hundreds of miRNAs have been identified through homology search, small RNA cloning and next generation sequencing. Real-time RT-PCR and microarray experiments reveal that many miRNAs are expressed in a tissue-specific or spatiotemporal-specific manner in farm animals. Limited functional studies suggest that miRNAs have important roles in muscle development and hypertrophy, adipose tissue growth, oocyte maturation and early embryonic development in farm animals. Increasing evidence suggests that single-nucleotide polymorphisms in miRNA target sites or miRNA gene promoters may contribute to variation in production or health traits in farm animals.     

内蒙古典型草原优化放牧管理模拟研究——以内蒙古太仆寺旗为例

针对太仆寺旗公共草地全年连续放牧的传统放牧方式,通过控制性试验,并结合太仆寺旗多年的草地、家畜、经济和气象等数据,建立中国西部草地生态经济模型,对太仆寺旗典型草原公共放牧系统进行模拟分析。以草原生态恢复和牧民收入增加为目的,对典型草原的最适载畜率、家畜在冬春季节的合理补饲等问题进行探讨,提出了典型草原放牧管理优化模式。研究结果表明,从当年10月到翌年5月份,家畜能量需求与放牧、补饲能量供给严重不平衡,家畜体重下降;随着载畜率的增加,牧民年均净收入先增加后降低,在载畜率为2.275羊单位/hm2时,收入达到最高;太仆寺旗最适载畜率为每公顷1.55-2.275羊单位。降低载畜率、加强补饲、提高草地质量都有利于提高牧民收入。     

Rhodnius prolixus and Rhodnius robustus–like (Hemiptera, Reduviidae) wing asymmetry under controlled conditions of population density and feeding frequency

Habitat change in Rhodnius spp may represent an environmental challenge for the development of the species, particularly when feeding frequency and population density vary in nature. To estimate the effect of these variables in stability on development, the degree of directional asymmetry (DA) and fluctuating asymmetry (FA) in the wing size and shape of R. prolixus and R. robustus–like were measured under laboratory controlled conditions. DA and FA in wing size and shape were significant in both species, but their variation patterns showed both inter-specific and sexual dimorphic differences in FA of wing size and shape induced by nutrition stress. These results suggest different abilities of the genotypes and sexes of two sylvatic and domestic genotypes of Rhodnius to buffer these stress conditions. However, both species showed non-significant differences in the levels of FA between treatments that simulated sylvan vs domestic conditions, indicating that the developmental noise did not explain the variation in wing size and shape found in previous studies. Thus, this result confirm that the variation in wing size and shape in response to treatments constitute a plastic response of these genotypes to population density and feeding frequency.     

Prenatal stress,immunity and neonatal health in farm animal species

The high pre-weaning mortality in farm animal species and poor welfare conditions of reproductive females question modern industrial farming acceptability. A growing body of literature has been produced recently, investigating the impact of maternal stress during gestation on maternal and offspring physiology and behavior in farm animals. Until now, the possible impact of prenatal stress on neonatal health, growth and survival could not be consistently demonstrated, probably because experimental studies use small numbers of animals and thus do not allow accurate estimations. However, the data from literature synthesized in the present review show that in ungulates, maternal stress can sometimes alter important maternal parameters of neonatal survival such as colostrum production (ruminants) and maternal care to the newborn (pigs). Furthermore, maternal stress during gestation can affect maternal immune system and impair her health, which can have an impact on the transfer of pathogens from the mother to her fetus or neonate. Finally, prenatal stress can decrease the ability of the neonate to absorb colostral immunoglobulins, and alter its inflammatory response and lymphocyte functions during the first few weeks of life. Cortisol and reproductive hormones in the case of colostrogenesis are pointed out as possible hormonal mediators. Field data and epidemiological studies are needed to quantify the role of maternal welfare problems in neonatal health and survival.     

河南新郑望京楼遗址出土的动物骨骼及其反映的家养动物的差异化

聚落考古研究表明,二里头文化时期（1750~1530 BC）中原腹地出现了都邑和大、中、小型四级聚落系统,东亚地区由此进入了早期广域王权国家时代。二里头文化时期的生业经济研究对于理解中华文明形成与早期发展过程中的关键时期的社会变革与文化演进的骤然提速具有重要意义。家养动物及其副产品的开发和利用、管理和分配是生业经济研究和社会复杂化发展的重要内容。在以往研究中,尽管学界已对二里头文化时期的核心都邑二里头遗址和若干中小型聚落遗址开展了多项动物考古学研究,但是针对大型聚落的系统分析较少。鉴于此,本文以河南省新郑市望京楼遗址发掘出土的动物骨骼为研究对象,通过种属鉴定、数量统计、测量数据分析、死亡年龄推算等方法,尝试探讨居于大型聚落的先民对动物资源的消费和利用。结果显示,该遗址的家养动物有猪、黄牛、绵羊、山羊和狗,家养动物数量占多数。遗址的猪多数为未成年个体,说明肉食消费是遗址先民养猪的主要目的;绵羊多数为成年个体,说明获取羊毛是遗址先民养羊的主要目的。通过与二里头、南洼、煤山和皂角树等其他等级聚落遗址的比较可知,早期国家的都邑和大中型聚落的家养动物的种类更丰富,绵羊的数量比例随聚落等级的降低而减少,绵羊的身体尺寸随聚落等级的降低而变小,以获取羊毛为主要目的养羊业更容易在高等级聚落中出现。这一研究揭示了早期国家大型聚落和国家内部不同等级聚落开发利用动物资源的特点和差异,为从动物考古的角度探讨早期社会复杂化提供了可能性。     

Seasonality of reproduction and production in farm fishes, birds and mammals

A very large majority of farm animals express seasonal variations in their production traits, thus inducing seasonal availability of fresh derived animal products (meat, milk, cheese and eggs). This pattern is in part the consequence of the farmer's objective to market his products in the most economically favourable period. It may also be imposed by the season-dependent access to feed resources, as in ruminants, or by the specific requirements derived from adaptation to environmental conditions such as water temperature in fish. But seasonal variations in animal products are also the consequence of constraints resulting from the occurrence of a more or less marked seasonal reproductive season in most farm animal species including fish, poultry and mammals. Like their wild counterparts, at mid and high latitudes, most farm animals normally give birth at the end of winter-early spring, the most favourable period for the progeny to survive and thus promote the next generation. As a consequence, most species show seasonal variations in their ovulation frequency (mammals and fish: presence or absence of ovulation; birds: variations or suppression of laying rates), spermatogenic activity (from moderate to complete absence of sperm production), gamete quality (variations in fertilisation rates and embryo survival), and also sexual behaviour. Among species of interest for animal production, fishes and birds are generally considered as more directly sensitive to external factors (mainly temperature in fish, photoperiod in birds). In all species, it is therefore advisable that artificial photoperiodic treatments consisting of extra-light during natural short days (in chickens, turkeys, guinea fowl, sheep and goats) or melatonin during long days (in goats, sheep) be extensively used to either adjust the breeding season to animal producer needs and/or to completely overcome seasonal variations of sperm production in artificial insemination centres (mammals) and breeder flock operations (poultry, fish farming). Pure light treatments (without melatonin), especially when applied in open barns, could be considered as non invasive ones which fully respect animal welfare.