Non-invasive monitoring of adrenocortical function in female domestic pigs using saliva and faeces as sample matrices

Intensive pig management involves in a commercial setting the housing and implementation of certain procedures, such as castration and tail docking, which may be stressful for the animal. Good farming practices include the reduction of stress due to management processes, but assessing the level of stress perceived entirely through behavioural observations can be challenging. The monitoring stress-related physiological markers, like glucocorticoids (GC), can be an accurate alternative that would presumably be more objective. In order to avoid an additional stressor by taking blood, a non-invasive approach is advisable. We used an adrenocorticotropic hormone (ACTH) stimulation test and the effect of transport to examine the suitability of different enzyme immunoassays (EIAs) for monitoring adrenocortical function in domestic pigs using saliva and faeces as sample matrices. An assay measuring faecal glucocorticoid metabolites (fGCMs) with a 3ß,11ß-diol group has proven suited to determine adrenocortical activity, showing an overall increase of 180% in fGCM concentrations related to ACTH administration and of 70% related to transport, respectively. A cortisol EIA was used to detect salivary glucocorticoid (sGC) concentrations, revealing a 1100% increase in sGC concentrations after ACTH administration. The stability of fGCM concentrations post-defecation was determined to assess possible changes in measured fGCM concentrations in unpreserved faecal material over time, with fGCM concentrations being relatively stable (maximal 12% change) under natural conditions for approximately two days after defecation. This implicates that untreated faecal material from pigs can be analysed for up to two days after collection without appreciable level of depreciation in fGCM concentrations. Being able to assess the physiological stress response of domestic pigs non-invasively can help to improve the well-being of commercially reared pigs.The National Research Foundation Incentive funding for Rated Researchershttp://www.plosone.orgam2021Anatomy and PhysiologyMammal Research InstituteProduction Animal Studie

Is being with girls stressful? Social environment influences hormone levels in male giraffes

Giraffes (Giraffa camelopardalis giraffa) live in a fission-fusion social system, characterized by the splitting and reunion of subgroups within a larger social network. Adult bulls show a roaming tactic to search for fertile females, whereas younger bulls are often seen in all male groups. In this study we combined behavioural observations with hormonal data. Therefore, a giraffe population of about 80 individuals (11 adult males, 28 adult females, and 32 juvenile / sub-adult animals) was monitored six days a week from dawn to dusk for a period of 12 months (Nov 2014–Oct 2015). Giraffes were individually identified by their unique pelage pattern and adult bulls assigned to age classes based on their appearance (A, B, and C), with class A bulls being the oldest and tallest. A total of 790 faecal samples were collected and analysed for faecal androgen (fAM) and glucocorticoid metabolite (fGCM) concentrations. Class A bulls show significantly higher fAM levels compared to younger bulls, with lowest fAM levels found for the juvenile / sub-adult group. Longer periods of increased fAM levels in the oldest bulls mainly occur during summer and are associated with an observed birthing peak. Within class A, fAM levels of bulls in all male groups are significantly lower than when associated with females, however, these levels are still significantly higher compared to respective fAM levels from youngest males. No significant differences in overall fGCM levels could be found between the different age classes. However, within class A the bulls show a trend for higher fGCM levels when sexually active compared to when associated with an all-male group. In contrast, juvenile / sub-adult bulls show highest fGM levels when they are in all-male groups, which is possibly linked to intrasexual competition as younger bulls still need to establish their position within the hierarchy.Poster presented at the University of Pretoria, Faculty of Veterinary Science Faculty Day, August 25, 2016, Pretoria, South Africa.ab201

Impact of foot-and-mouth-disease on goat behaviour after experimental infection with serotype SAT1 virus

Infectious diseases and parasitic infestations can cause a set of non-specific clinical signs, such as increased body temperature and resting, and a decrease in food intake. These physiological and behavioural changes have an adaptive function facilitating defences against the pathogen and to support immune functions. These so-called’ sickness behaviours’ can also be used as an early detection tool for disease. Foot-and-mouth disease (FMD) still causes great economic losses in endemic countries, especially to smallholder farmers. The aim of this study was to determine if behavioural changes in goats can be used as an early indicator of FMD virus (FMDV) infection. The efficacy of a Southern African Territories (SAT) FMD vaccine was studied on forty South African indigenous goats. Changes in daily activities (resting, feeding, walking), as well as social behaviours (social resting, social feeding, dominance behaviours) were recorded and then compared over time and between clinically affected and unaffected goats. Pedometers were used to estimate average daily steps and to compare between groups of study animals. Eleven goats developed clinical signs of FMD, as well as non-FMD related sicknesses during the course of the study. Overall walking and resting behaviours were not significantly affected by the presence of FMD related clinical signs (p > 0.05). However, during the time of FMDV infection, social resting increased significantly (p < 0.001). Although goats developed FMD lesions on lips and tongues, percentage of time feeding was not affected (p = 0.762), suggesting that the study goats did not perceive the oral lesions as an important disturbance. Similarly, the number of steps did not consistently decrease in the presence of FMD-associated foot lesions. When affected by non-FMD related sicknesses, animals did not have an overall reduction in the time spent feeding (p = 0.867). However, goats affected with non-FMD conditions reduced the amount of social feeding (p = 0.002), potentially avoiding energetically costly competition at the feeding points. Overall, goats affected with FMD did not show more sickness behaviour, suggesting that FMDV infection in goats might not lead to obvious and therefore, easily detectable behavioural changes. This might have implications for farmers and animal health personnel, as individual goats infected with FMDV might be undetected within a flock due to the absence of obvious sickness behaviours, and the virus can therefore be spread more easily between herds through animal movements.The National Research Foundation (NRF), South Africa and the Peace Parks Foundation.http://www.elsevier.com/locate/prevetmedhj2021Mammal Research InstituteProduction Animal Studie

Seasonal changes in social networks of giraffes

Fission‐fusion social societies allow animals to respond in a flexible manner to environmental changes by adapting the size and composition of a group. Although group members change frequently in these systems, associations with preferred partners may be found. In this study, we examined the grouping patterns of a population of 80 individual giraffes in a fenced South African game reserve over a 12‐month period. Using social network analyses as a tool to evaluate observed associations, we subsequently analysed both sex‐ and season‐related grouping patterns within the study population. Mixed sex groups represented 49% of all groups observed, and although overall group composition distribution did not differ significantly between seasons, the number of encountered single females decreased by 50%, whereas the number of multi‐male groups increased by over 50% in winter. Overall average group size did not differ significantly between seasons, but significantly larger multi‐female and multi‐male groups were seen in winter. Within the social network, two distinct clusters were found in summer, with the population more divided in winter, with five distinct clusters emerging. The strongest ties (highest HWIGs) were found between adult females. Our study revealed that giraffes not only live in a highly flexible social fission‐fusion system, but also show seasonal patterns of grouping.The National Research Foundation, South Africa and a postgraduate bursary from the DST-NRF SARChI chair for Mammal behavioural ecology and physiology to (NCB).http://onlinelibrary.wiley.com/journal/10.1111/(ISSN)1469-79982019-06-01hj2018Anatomy and PhysiologyCentre for Veterinary Wildlife StudiesZoology and Entomolog

Improving foot-and-mouth disease control through the evaluation of goat movement patterns within the FMD protection zone of South Africa

Foot-and-mouth disease (FMD) is a transboundary animal disease that has a major impact on livestock production, regional and international trade and livelihoods of smallholder farmers in endemic settings. Many livestock diseases are transmitted through direct contact between animals, and thus between herds and flocks through animal movements. In this study, we described the pattern of goat movements among smallholder farmers within a communal farming area in South Africa. A cross-sectional survey using a semi-structured questionnaire was administered to 116 respondents, and separate 13 focus group discussions employing participatory mapping and semi-structured interviews were conducted among smallholder farmers. Overall, 22% (95% confidence interval [CI]: 16 – 31) of questionnaire respondents indicated moving new animals into their holdings during the previous 12 months while 56% (95% CI: 47 – 65) reported moving animals out of the holdings during the same timeframe. A total of 134 participants attended the focus group discussions with 68% (91/134) being male and 32% (43/134) female. Data from the study reported 37 nodes and 78 ties with an overall network density of 0.059 (SD 0.2) across the study area. Four locations within the (former) FMD-free zone of the country had connections with movement of goats from the study area. Furthermore, 60% (95% CI: 51 – 69) of farmers were ignorant of the need to obtain official veterinary movement permits for goats. These animal movements put the country at risk of future FMD outbreaks within the free zone. We recommend that the relevant authorities implement risk-based control measures to prevent the spread of infectious diseases.http://www.elsevier.com/locate/smallrumres2022-06-05hj2021Mammal Research InstituteProduction Animal Studie

Noninvasive measurements of ovarian activity in Beira antelope (Dorcatragus megalotis)

As the natural habitat of more and more species becomes depleted, captive breeding programmes have become established to bring species back from the brink of extinction. Monitoring the reproductive status of an individual is essential in order to improve breeding success. Traditional methods have involved stressful blood sampling, and thus noninvasive methods have been proven to be reliable alternatives for monitoring reproductive function in both captive and free‐ranging animals. Subsequently, noninvasive methods have become an invaluable tool in longitudinal studies and conservation efforts, as animals can be observed without, or minimal human contact. The Beira antelope is a small antelope endemic to the northern part of the Horn of Africa. Population numbers of the Beira have been declining over the last few decades due to habitat fragmentation. We show here that the reproductive cycle of female Beira antelopes can be monitored noninvasively, by using faecal samples to analyse oestrogen (fEM) as well as progestagen (fPM) metabolites. The profiles of fPM and fEM of both females showed regular cyclic patterns in which the follicular and luteal phases could be distinguished. The overall mean cycle length is 22 days (range: 21–25 days), with a mean length of the follicular phase of 6 days (range: 4–7 days) and a mean length for the luteal phase being 15 days (range: 12–16 days). The suitability of these noninvasive techniques should assist in optimizing breeding efforts of this endemic small antelope in captivity. Being noninvasive, this method could also be a useful tool for monitoring reproductive function in the dwindling wild populations.Al Wabra Wildlife Preservationhttp://wileyonlinelibrary.com/journal/rda2020-02-01hj2018Mammal Research InstituteZoology and Entomolog

Physiological measure of animal welfare in relation to semi-captive African Elephant (Loxodonta africana) interaction programs

Elephant interaction programs, specifically ones that provide elephant back riding, have come under public scrutiny, and little information exists to show whether these activities affect animal welfare. This study examined the impact of human interactions and ride-based activities on physiological stress-related indicators in African elephants. Fifteen trained semi-captive elephants, as well as free-ranging elephants roaming under the same ecological conditions, were monitored. Faecal samples were collected over a nine-month period from both groups and these were analysed using an enzyme immunoassay detecting faecal glucocorticoid metabolites (fGCMs) with a 5β-α-ol-11-one structure. Elephants that participated in elephant-back-safari (EBS) activities showed significant decreases in fGCM concentrations when EBS were discontinued. Similarly, fGCM concentrations of the trained semi-captive individuals that did not participate in EBS showed decreased steroid concentrations over the same time. Overall, fGCM concentrations of the trained semi-captive herd and the free-ranging herd did not differ significantly. The collected data will help to better understand the physiological and behavioural requirements of semi-captive elephants with frequent exposure to humans. The findings will also help to optimise management strategies for wild elephant populations and elephants living in controlled environments on reserves exposed to wildlife tourism.https://www.tandfonline.com/loi/tafz20hj2021Anatomy and PhysiologyMammal Research InstituteZoology and Entomolog

The impact of age-class and social context on fecal glucocorticoid metabolite levels in free-ranging male giraffes

One of the primary sources of perceived stress is the social environment of an animal and the interactions with conspecifics. An essential component of the response to a stressor is the activation of the hypothalamic–pituitary–adrenocortical axis, which results amongst others in a temporal increase in circulating glucocorticoid (GC) levels. Giraffes occur in a highly flexible fission-fusion social system and group compositions can change on a daily basis, with bulls establishing an age-related dominance hierarchy and showing a roaming strategy in the search for fertile females. The aim of this study was to non-invasively monitor the influence of different group compositions (mixed sex groups vs. all-male groups) on GC concentrations in free ranging giraffe bulls of different age classes. We collected fecal samples from free-ranging giraffe bulls for 12 months in a South African Private Game Reserve to examine age- and social context-related patterns of fecal GC metabolite (fGCM) concentrations. We found that fGCM levels in giraffe bulls are age-class dependent, as well as associated with changes in the social environment. Independently of the social setting, bulls of the youngest age class exhibited the highest fGCM levels compared to bulls of the other two older age-classes, with differences most pronounced when the bulls are associated in all-male groups. In contrast, an almost reversed picture appears when looking at the fGCM levels of sexually active individuals in mixed sex groups, where highest levels were found for the bulls in the oldest age-class, and the lowest for the bulls in the youngest age-class. The study stresses the importance to taking factors such as age-related status and social settings into account, when interpreting fGCM levels in free ranging giraffes.The National Research Foundation, South Africa; a postgraduate bursary from the DST-NRF SARChI chair for Mammal behavioural ecology and physiology to (NCB); Novartis/South African Veterinary Foundation Wildlife Research Fund.http://www.elsevier.com/locate/ygcen2019-01-01hj2017Anatomy and PhysiologyCentre for Wildlife ManagementMammal Research InstituteZoology and Entomolog

The relationship between physical injury, body condition and stress-related hormone concentrations in free-ranging giraffes

A physiological stress response can be triggered by a variety of intrinsic and extrinsic stimuli, but minimal information is available about the physiological stress response related to pain in wildlife. Recently established techniques now allow the non-invasive measurement of faecal glucocorticoid metabolite (fGCM) concentrations to monitor the physiological stress response in giraffe. We examined the consequences of injury of various severities and loss of body condition in relation to glucocorticoid output in free-ranging giraffes. Body condition (BC) was visually estimated based on the amount of fat and muscle covering the bones, using a species-specific scoring system (one – emaciated to eight – obese). An adapted animal trauma triage scoring system was also applied to evaluate the severity of injuries observed. Individual fGCM concentrations were determined to assess stress-related glucocorticoid output using an enzyme immunoassay technique, and compared with assigned BC and injury scoring. Significantly elevated fGCM levels were found in injured individuals that showed wounds with deep tissue involvement and/or poor BC, but not in individuals that showed superficial wounds. Responsible for the observed changes in fGCM levels may be a combination of differences in the severity of the injuries and the subsequent degree of pain associated with it, the influence of the stress response on the energetic condition, and the duration of the injuries. The results of this study are somewhat limited due to the small sample size, and therefore the effect of food intake on the body conditions cannot be controlled for. However, euthanasia is a common management tool used to prevent unnecessary suffering, nevertheless, especially in wild animals the severity of an injury and the associated pain perceived may be difficult to assess. Combining an assessment of BC and analysis of individual stress-hormone levels can help improve health assessments in free-ranging giraffes and thus assist management decisions.All Out Africa provided support for this research.http://www.wildlifebiology.orgam2019Zoology and Entomolog