The Impact of Abrupt and Fenceline-Weaning Methods on Cattle Stress Response, Live Weight Gain, and Behaviour.

The impact of abrupt (AB) and fenceline (FL) weaning methods on cattle stress response, live weight gain, and behaviour were determined across 14 days. Thirty-two cow-calf pairs were fitted with ear tag sensors (to continuously record behaviour) and allocated to two weaning treatments. After separation, FL calves were maintained in a pen adjacent to the FL cow paddock. The AB calves were transported to a pen removing all contact with the cows. After 7 d, FL cows were transported away from all calf pens. Body weights and salivary samples were collected for all animals on experimental days 0, 7, and 14. Fenceline-weaned calves had a greater duration of rest and rumination with reduced high activity across the first 3 days after separation as compared to abruptly weaned calves in line with the greater occurrences of pacing observed for AB calves. Fenceline-separated cows had greater levels of rest across the first 7 days but similar levels of rumination compared to abruptly separated cows. Fenceline-separated cow activity levels tended to be greater and eating levels were similar across the first three days. Body weight (BW) and cortisol concentrations were similar for AB and FL cattle, but FL cows had lower overall weight gain than the abrupt cows likely due to reduced eating time on days four to seven. Together, these results suggest that calves be fenceline-weaned for three days followed by total separation.

Alpaca Field Behaviour When Cohabitating with Lambing Ewes.

A common strategy to reduce predator attack on livestock is the deployment of guardian alpacas. However, little research has been conducted on the behaviour of this species while housed with other livestock. This study monitored two male alpacas cohabitating with 180 lambing ewes in order to quantify field behaviour in two phases. Phase one assessed diurnal patterns of alpacas and lambing ewes using Global Navigation Satellite System (GNSS) collars recording data over 41 days, in combination with observational recordings. Phase two developed an alpaca behavioural ethogram through continuous observations from 05:30 to 19:30 h over a 3-day period. The two alpacas shared similar behaviours with commonality of distance travelled, and both species exhibited an increase in activity level based on speed between the times of 05:00 and 17:00 h. The GNSS data indicated that the alpacas flocked with the ewes at night sharing the same resting location, however, would spend time during the day on the outskirts of the paddock. Alpacas were observed to spend the majority of the observation period in two behavioural states: grazing (57%) and resting (27%). As a result of this study we were able to catalogue a range and frequency of field behaviours which alpacas exhibit while cohabitating with lambing ewes. However, further research is needed to determine in more detail how these behaviours correspond with the effectiveness of this species as a livestock guardian.

Automated Monitoring of Panting for Feedlot Cattle: Sensor System Accuracy and Individual Variability.

Heat stress causes significant economic losses by reducing the productivity and welfare of cattle whilst requiring a significant investment in resource for amelioration. Panting score (PS) is considered a robust indicator of cattle heat stress; however, individualised visual monitoring is impractical. Thermal index-based monitoring and mitigation decisions are applied at the herd level, but they have limited application for the individual animal. As such, an automated system to monitor the real-time animal response to heat stress is required for strategic mitigation. Our objectives were to validate an accelerometer-based ear tag sensor to monitor cattle panting and to determine individual variability in heat stress responses with reference to thermal indices. Two experiments were conducted: Experiment 1 validated the sensors, and Experiment 2 determined individual variability comparing sensor data against thermal indices. Ear tag sensors were fitted at feedlot entry to continuously monitor the behaviour of 100 steers of mixed breed in Experiment 1 and 200 steers and heifers of mixed breed in Experiment 2. Sensor-derived 'heavy breathing' was validated against visually observed PS. Sensor-derived behaviour bouts were analysed as 'raw', and single behaviour states were also converted to the preceding bout of ≥2 min, which was referred to as 'fill' data for the validation study. Our results demonstrate the sensors' ability to accurately monitor panting in feedlot cattle. Sensor-recorded 'heavy breathing' duration per animal was highly correlated to observed panting duration for both raw (r = 0.89) and fill (r = 0.90) data; however, the concordance correlation co-efficient was lower for raw (0.45) as compared with fill (0.76). Predicted agreement for raw data were 75%, 45%, and 68% and predicted agreement for fill data were 65%, 54%, and 83% for PS0, PS1, and PS2, respectively. Sensitivity for raw data were 39%, 37%, and 45% and for fill data, they were 59%, 54% and 82% for all PS data, PS1 and PS2, respectively. Specificity and positive predictive values for both raw (77% and 79%, respectively) and fill (65% and 77%, respectively) data show the probability of reporting false positives by sensors to be low. Experiment 2 revealed that the duration of panting increased from 0800 to 1700 h alongside changes in thermal indices with significant differences between and within breed and coat colour categories of cattle, suggesting that grouping and allocating heat amelioration measures by breed and coat colour can be effective in commercial feedlots. However, there was high variability (CV > 80%) in the duration of panting between individuals within the same breed and same coat colour, revealing the potential for strategic management at an individual level, and with the same data, genetic selection for heat resilience.

Core and peripheral site measurement of body temperature in short wool sheep.

Understanding circadian rhythms of body temperature is important for the interpretation of single body temperature measurements and the assessment of the physiological state of an animal. The ability to measure body temperature at peripheral locations may also be important in the development of minimally invasive tools for remote temperature measurement in livestock. This study aimed to investigate how well body temperature measured at peripheral sites reflected a commonly used core measurement (vaginal temperature) and the circadian rhythmicity of the body temperature of sheep with a view to practical application in extensive sheep production systems. Eleven crossbred ewes were implanted with peripheral temperature sensing microchips (LifeChip®) which were positioned transversely in the sternocleidomastoid (neck) muscle and subcutaneously under the tail. iButton® temperature loggers were placed intravaginally to record core body temperature measurements (Tv). The body temperature measurements observed at the peripheral sites in the neck (Tn) and tail (Tt) differed significantly to those measured at the core site, Tv (P < 0.05), with Tn lower than Tv and Tt lower than both Tv and Tn. Similarities in circadian rhythm patterns were observed across the day between Tv, Tn and Tt in repeated measures analysis, with a short period of difference between Tv and Tn (from 1400 to 1600 h) and a long period of difference between Tv and Tt (from 1000 to 2100 h) (P < 0.05). These results suggest that neck muscle temperature measurements may have utility in detecting circadian rhythm patterns in core temperature in sheep, but may not accurately reflect absolute core temperatures. Peripheral measures may require adjustment or correction to more accurately reflect absolute core temperature with respect to determining accurate clinical thresholds relative to the expected normal temperature for the time of day observed. Further investigation into the utility and application of peripheral measurement of body temperature is warranted.

The influence of lameness and individuality on movement patterns in sheep.

We investigated how individuality and lameness altered social organisation by assessing food-directed movement patterns in sheep. One hundred and ninety-six mature Merino ewes were walked in 16 different runs around a 1.1 km track following a food source. Flock position and lameness were measured and temperament was assessed using an Isolation Box Test. The mean value for the correlations of position between a run and the run preceding it was r = 0.55 ±â€¯SEM 0.03. All correlations between runs were positive (r = 0.08-0.76) and all but two were statistically significant (P < 0.05). The weakest and least statistically significant correlations were for run 14: where all 16 runs were conducted approximately 3 times a week, except with an interval of 20 weeks between runs 13 and 14. Additionally, there were differences in overall positions for a lame versus a non-lame individual (all P < 0.05) with lame sheep being further back in position when compared to their non-lame mean positions. These results indicate the movement patterns, as measured by flock position during a food-directed forced movement order are relatively stable provided tests occur frequently, possibly on a bi-weekly basis. However, further work will be required to better account for individual animal variation.

Stakeholder Perceptions of Welfare Issues and Indicators for Extensively Managed Sheep in Australia.

An online survey was designed to form the basis of a framework for the welfare assessment of extensively managed sheep in Australia. The survey focused on welfare compromise and useful welfare indicators. A total of 952 people completed the survey in its entirety, representing four stakeholder groups: Public (53.6%), Producer (27.4%), Scientist (9.9%), and Service provider (9.1%). Animal welfare was considered to be important by all participating groups in this survey (average score of 3.78/4). Respondents felt the welfare of grazing sheep was generally adequate but improvement was desired (2.98/5), with female members of the public rating sheep welfare significantly worse than other respondents (p < 0.05). Environmental issues were considered to pose the greatest risk to welfare (3.87/5), followed by heat stress (3.79), lameness (3.57) and husbandry practices (3.37). Key indicators recognised by all respondents were those associated with pain and fear (3.98/5), nutrition (4.23), mortality/management (4.27), food on offer (4.41) and number of illness/injures in a flock (4.33). There were gender and stakeholder differences in the perceived importance of both welfare issues and indicators with women and the public consistently rating issues (all p < 0.01) and indicators (all p < 0.05) to be of greater significance than other respondents. These results highlight the importance of including all stakeholders and an even balance of genders when developing a welfare framework that can address both practical and societal concerns.