Squeeze Chute Research Articles

271 Does social buffering amongst familiar weaned beef calves mitigate castration stressors?

Abstract Co-mingling of beef feeder calves from multiple sources results in biological and behavioral stressors. This study is part of a project exploring social relationships between individual beef cattle and potential benefits of social buffering during stress events. Here, the specific objective was to explore whether feeder calves form preferential relationships which buffer them from surgical castration pain. Within the experiment, two treatment groups were established: Familiar calves were defined as calves who shared a source farm with two other calves in the pen, and Unfamiliar calves were defined as calves who did not share a source with any other pen-mates. It was hypothesized that Familiar calves would exhibit more lying, fewer pain-related behaviors, and fewer agonistic interactions following surgical castration than Unfamiliar pen-mates. Weaned beef bull calves [n = 102, body weight (BW) range ± SD = 112.95 to 370.10 ± 67.8 kg] from 23 source farms were randomly assigned to home pens, each comprised of three Familiar calves and three Unfamiliar calves. Cameras placed above the pens recorded video from which postural (standing and lying), social (agonistic and bunk displacements) and pain-related behaviors (wound checking and hind leg stamping) were quantified. Cattle were handled through a hydraulic squeeze chute once weekly over four consecutive weeks for data collection and standard processing procedures. On d 14 relative to arrival, calves were surgically castrated with multimodal pain mitigation. During all processing events, calves were marked with livestock paint for behavioral observations. Behavior was observed continuously for 15 min at five different time points (0 h, 1 h, 4 h, 24 h, 48 h) relative to when the last calf returned to the home pen after processing, and researchers were blind to treatment allocation. These time periods corresponded to expected periods when pain was absent and present based on duration of local anesthesia and systemic pain relief. Calf was the experimental unit. For the purpose of this abstract, data from the 48 h periods following d 7 and 14 were analyzed using the PROC GLIMMIX procedure of SAS; the model included treatment (Familiar, Unfamiliar) by week interaction. A P-value of ≤ 0.05 was considered significantly different. Regardless of treatment, preliminary analyses identified decreased lying (P < 0.02) and increased wound checking (P < 0.01) 48h following castration (d 14) when compared with the previous week (d 7). There were no observed differences for hindleg stamping (P = 0.2), agonistic behaviors (P > 0.06) or bunk displacement (P = 0.09). Based on preliminary analyses, we did not observe evidence of social buffering effects on castration stress during the immediate post-surgical period.

Predictability in Achieving Target Intervertebral Lordosis Using Personalized Interbody Implants.

Lumbar lordosis distribution has become a pivotal factor in re-establishing the foundational alignment of the lumbar spine. This can directly influence overall sagittal alignment, leading to improved long-term outcomes for patients. Despite the wide availability of hyperlordotic stock cages intended to achieve optimal postoperative alignment, there is a lack of correlation between the lordotic shape of a cage and the resultant intervertebral alignment. Recently, personalized spine surgery has witnessed significant advancements, including 3D-printed personalized interbody implants, which are customized to the surgeon's treatment and alignment goals. This study evaluates the reliability of 3D-printed patient-specific interbody implants to achieve the planned postoperative intervertebral alignment. This is a retrospective study of 217 patients with spinal deformity or degenerative conditions. Patients were included if they received 3D-printed personalized interbody implants. The desired intervertebral lordosis (IVL) angle was prescribed into the device design for each personalized interbody (IVL goal). Standing postoperative radiographs were measured, and the IVL offset was calculated as IVL achieved minus IVL goal. In this patient population, 365 personalized interbodies were implanted, including 145 anterior lumbar interbody fusions (ALIFs), 99 lateral lumbar interbody fusions (LLIFs), and 121 transforaminal lumbar interbody fusions. Among the 365 treated levels, IVL offset was 1.1° ± 4.4° (mean ± SD). IVL was achieved within 5° of the plan in 299 levels (81.9%). IVL offset depended on the approach of the lumbar interbody fusion and was achieved within 5° for 85.9% of LLIF, 82.6% of transforaminal lumbar interbody fusions and 78.6% of ALIFs. Ten levels (2.7%) missed the planned IVL by >10°. ALIF and LLIF levels in which the plan was missed by more than 5° tended to be overcorrected. This study supports the use of 3D-printed personalized interbody implants to achieve planned sagittal intervertebral alignment. Personalized interbody implants can consistently achieve IVL goals and potentially impact foundational lumbar alignment.

Tomographic Assessment of Fusion Rate, Implant-Endplate Contact Area, Subsidence, and Alignment With Lumbar Personalized Interbody Implants at 1-Year Follow-Up.

Incongruity between irregularly shaped vertebral endplates and the uniform surfaces of stock interbody fusion cages has been identified as contributing to cage subsidence, pseudarthrosis, and unpredictable alignment. Advances in manufacturing techniques have driven the development of personalized interbody cages (PICs) that can match individual endplate morphology and provide the exact shape and size needed to fill the disc space and achieve the planned correction. This study used computed tomography (CT) imaging to evaluate the implant-endplate contact area, fusion, subsidence, and achievement of planned alignment correction in patients receiving PIC devices. This retrospective study included patients treated for adult spinal deformity at a single site and implanted with PIC devices at L4 to L5 or L5 to S1 for segmental stabilization and alignment correction, who received 1-year postoperative CT images as part of their standard of care. An evaluation using 3-dimensional thin-section scans was conducted. Implant-endplate contact and signs of fusion were assessed in each CT slice across both endplates. The degree of subsidence as well as measures of segmental and global lumbar alignment were also assessed. Fifteen patients were included in the study, with a mean age of 68.2 years. Follow-up ranged between 9 and 14 months. Twenty-six total lumbar levels were implanted; 20 with PIC devices via the anterior lumbar interbody fusion approach, 2 with stock cages via the anterior lumbar interbody fusion approach, and 4 with PIC devices via the transforaminal lumbar interbody fusion approach. CT analysis of PIC-implanted levels found an overall implant-endplate contact area ratio of 93.9%, a subsidence rate of 4.5%, a fusion rate of 100%, and satisfactory segmental and global lumbar correction compared with the preoperative plan. PIC implants can provide nearly complete contact with endplate surfaces regardless of the individual endplate morphology. Subsidence, fusion, and alignment assessments in this tomographic study illustrated results consistent with the benefits of a personalized interbody implant.

89 Evaluation of repeatability of anogenital distance measured with either a caliper or photogrammetry

Abstract The objective was to determine the repeatability of anogenital distance (AGD) measurements over time in growing heifers and evaluate the relationship of photogrammetric and caliper AGD measurements. Reproductive success is one of the most important determinants of profitability in the beef industry. However, fertility traits generally have low heritability, and there are few phenotypic traits that correlate to fertility in beef cattle. The AGD is the distance from the center of the rectum to the base of the clitoris. Recently, researchers in dairy cattle have reported a correlation between shorter AGD and improved fertility. In the published dairy research, AGD has been measured with the use of calipers. Photogrammetric measurement could be a quicker and safer way of taking the measurement and easier to implement on farm. Heifers (n = 153), either Angus or Hereford sired by commercial dams, were used in the analysis. Heifers were early weaned at 82 ± 7 d of age. Following weaning, heifers were managed in partially covered, dry lot pens and fed a moderate roughage growing diet. The heifers rotationally grazed predominantly tall fescue pastures beginning in April of 2023. Heifer AGD was evaluated monthly from June to September. Heifers weighed 210 ± 22 kg and 282 ± 6 d of age at the time of the first AGD measurements. Heifer body weight was collected monthly at time of AGD measurements. The heifers were restrained in a squeeze chute and had their tail held in a relaxed upright position and AGD was measured with a caliper. Immediately following caliper measurements, anogenital photographs were taken with an Iphone 14 plus. A white board with a forensic photomacrographic scale attached and the ear tag number recorded on the right corner was held adjacent to the vulva and was included in the photograph. Photographs were converted from HEIC to JPEG. A software program, Digitizer, was used to set the measurement scale using the forensic photomacrographic scale. The AGD was then digitally measured from the center of the rectum to the base of the clitoris. Repeatability of AGD and relationship of caliper and photogrammetric AGD were evaluated using the CORR procedure of SAS 9.4. Caliper AGD measurements were repeatable as all of the time points were moderately correlated (r ≥ 0.47; P ≤ 0.01) throughout the evaluation period. Photogrammetric AGD measurements were also repeatable as all of the time points were correlated (r ≥ 0.21; P ≤ 0.02) throughout the evaluation period. Photogrammetric AGD had a moderate correlation (r ≥ 0.44; P ≤ 0.01) with the caliper AGD measurements. In conclusion, AGD measurements were repeatable in growing heifers regardless of measurement method. Photogrammetric measurements may be a viable option for estimating AGD as they were strongly correlated to caliper measurements of AGD.

130 Effect of an appeasing substance application on growth, stress, handling quality and reproduction of Bos indicus beef heifers synchronized to fixed-time AI

Abstract This experiment evaluated the effects of an analogue of bovine appeasing substance (BAS) on growth, stress, handling quality, and reproduction of Nellore heifers. Twenty-nine heifers [body condition score (BCS) = 4.84 ± 0.13; body weight (BW) = 371 ± 0.77 kg; 23 ± 2 months of age)] were assigned to 1 of 2 treatments: 1) Saline solution (0.9 NaCl; n = 14) or BAS (Secure Cattle, IRSEA Group, Quartier Salignan, France; n = 15). Both solutions were applied topically in the nuchal skin area (5 mL/heifers) at the beginning (d -9) of the fixed-time artificial insemination protocol (FTAI). Heifers were allocated in two different pastures according to the treatment (one pasture per treatment) for 15 d (time of action of BAS) and then combined in a single group (both treatments in the same pasture). Heifers were inseminated on d 0, and BW and BCS were collected on d -9 and 40. The temperament in the squeeze chute (entry and exit scores; scale 1 – 3; chute score; scale 1 – 5; greater values mean more reactive heifers) and blood samples were collected on d -9, 0, 7, 14 and 30. The percentual of aggression, accident, and dirtiness in the perineal region were evaluated on d 0 along with time to inseminate, estrus expression scores (scale 1 – 3; 1 = no expression, 2 = low expression, 3 = greater expression), and dominant follicle size. The corpus luteum size was measured on d 7 and 14, and the pregnancy and embryo size on d 40. The BAS vs. Saline-treated heifers tended to have greater BW change (23.6 vs. 20.8 ± 1.03 kg; P = 0.09) and had greater BCS change (0.05 vs. -0.21 ± 0.05; P < 0.01). The BAS vs. Saline-treated heifers tended to have lesser entry scores (1.42 vs. 1.67 ± 0.09; P = 0.09) and percentual of dirtiness in the perineal region (48.3 vs. 71.1 ± 8.67 %; P = 0.06), and no effects of treatment were detected (P ≥ 0.39) for chute score, exit score, aggression, accident and time to inseminate. The BAS vs. Saline-treated heifers had greater estrus scores (2.00 vs. 1.27 ± 0.21; P = 0.03), and no effects were detected (P ≥ 0.11) for ovarian variables, pregnancy rate, and conceptus size. Furthermore, no treatment effects were detected (P ≥ 0.25) for serum concentration of cortisol and plasma concentration of haptoglobin, ceruloplasmin, and progesterone. Therefore, BAS application at the beginning of the FTAI protocol could decrease the temperament and dirtiness in the perineal region and increase the growth and estrus expression of beef heifers.

Study on the temperament of cows of the Limousin cattle breed

The temperament of 322 cows of the Limousin cattle breed reared in 10 farms on the territory of Bulgaria was studied. The data used comprise the period from 2017 to 2022. The animals in the study were between the age of 3 and 7 years. The temperament of cows reared under two different technologies was compared, and the influence of the age was also taken into account. The cows reared under one of the technologies were mostly pasture-bred and had no frequent interaction with people. The cows reared under the second technology were mostly kept in the farm and had frequent interaction with their handlers. An analysis of the temperament was performed, through a scoring system from 1 to 5, based on a visual assessment of the behavior during a manipulation in a cattle crush. The temperament of the Limousin cows received an average score of 3,22 ± 0,06. The age group, within the method of rearing, did not have a significant influence on the parameter display. There was a tendency towards a calmer temperament upon walking along a cattle alley and a crush observed with the age increase of the Limousin cows. The temperament of the cows reared in herds which had no interaction with people was evaluated with the average score of 3,43 ± 0,11, and that of the cows reared in an environment in which they had frequent interaction with people was assessed with an average score of 2,91 ± 0,08.

Temperature and humidity index (THI) affects salivary cortisol (HC) and dehydroepiandrosterone (DHEA) concentrations in growing bulls following stress generated by performance test procedures.

The hypothalamus-pituitary-adrenal axis response to a challenge was proposed for genetic selection of robust and resilient animals. As ACTH (adrenocorticotropic hormone) test and hormone measurements in blood may result impractical, it may be useful to measure salivary hormones in response to natural stressors, after an accurate biological validation, to control factors that could contribute to the response. We evaluated whether animal handling during performance test affects salivary HC and DHEA secretion and could be used for selection. We tested the effects of habituation to repeated handling and THI as putative bias. Bull calves (N = 273) undergoing performance test were sampled at 8-9 and 11-13 months (N = 101), 8-9 months (N = 131), or 11-13 months (N = 41). On each test day (D0), calves were isolated, conducted to a squeeze chute and immobilized for 6 min. Saliva samples were collected in the morning after feed administration (T0), and after 6 min immobilization in the squeeze chute (T1) for HC and DHEA measurement. Environmental temperature and relative humidity were recorded every hour from 1:00 h to 24:00 h during the 6 days before the performance test and on D0. Salivary HC and DHEA concentrations were higher in T1 (p < 0.01), although a clear individual positive response to handling could be observed in less than 10% of subjects. The mixed model revealed: (i) HC and HC/DHEA were higher in Young bulls (p < 0.05). (ii) The time of T0 sample collection significantly affected DHEA (p < 0.01) and HC/DHEA (p < 0.05). (iii) THI affected both steroids (p < 0.001) but not HC/DHEA. Spearman correlations suggested that THI weakly affected salivary HC at T0 only (ρ = 0.150, p < 0.01), while moderate statistically significant correlations were found between DHEA and THI at T0 (ρ = 0.316, p < 0.001), and T1 (ρ = 0.353, p < 0.001). Salivary HC and DHEA in response to handling procedures might identify subpopulations of subjects with sensitive HPA axis. Habituation to repeated handling played a role, as the hormone response was lower in older animals. Chronic exposure to high THI had a minor effect on salivary HC visible at T0. A more intense THI effect was observed on salivary DHEA concentrations at both T0 and T1, which should be worth of further investigations.

Is the temperament of crossbred dairy cows related to milk cortisol and oxytocin concentrations, milk yield, and quality?

Reactive dairy cows are more susceptible to stress, and this may result in negative effects on milk yield and quality. The aims of this study were to investigate the relationships between temperament traits and concentration of milk cortisol and oxytocin, milk yield, milkability, and milk quality in Holstein-Gyr cows. Temperament traits were assessed in 76 Holstein-Gyr cows in the milking parlor (by scoring milking reactivity and recording the numbers of steps and kicks during pre-milking udder preparation and when fitting the milking cluster) and during handling in the corral (by measuring the time to enter in the squeeze chute, ET and flight speed, FS). Milk samples were collected for milk quality (% fat, % protein, % lactose, and somatic cell count, SCC), and milk cortisol and oxytocin. Milk yield, milking time, and average flow were also measured. The calmer cows during milking management (class 'low') produced milk with higher protein (p = 0.028) content and tendencies for lower fat (p = 0.056) and higher lactose (p = 0.055) contents. Regarding the hormones, the most reactive cows (class 'high') in the milking and handling corral produced milk with higher concentrations of cortisol (p<0.001) and oxytocin (p = 0.023). In addition, the temperament of the animals affected some of the productive measures evaluated. Cows with reactive temperament had lower milk flow and longer milking time than the intermediate ones and had higher fat and a tendency for lower protein percentage in milk compared to cows with intermediate temperaments. Calm and intermediate cows in the handling corral produced more milk and presented better milkability parameters, such as a shorter milking time and greater average milk flow. Our results suggest that the cows' behavioral reactivity can be related to the intensity of their response to stress during handling.

Species ex machina: ‘the crush’ of animal data in AI

AbstractA canonical genealogy of artificial intelligence must include technologies and data being built with, for and from animals. Animal identification using forms of electronic monitoring and digital management began in the 1970s. Early data innovations comprised RFID tags and transponders that were followed by digital imaging and computer vision. Initially applied in the 1980s for agribusiness to identify meat products and to classify biosecurity data for animal health, yet computer vision is interlaced in subtler ways with commercial pattern recognition systems to monitor and track people in public spaces. As such this paper explores a set of managerial projects in Australian agriculture connected to computer vision and machine learning tools that contribute to dual-use. Herein, ‘the cattle crush’ is positioned as a pivotal space for animal bodies to be interrogated by AI imaging, digitization and data transformation with forms of computational and statistical analysis. By disentangling the kludge of numbering, imaging and classifying within precision agriculture the paper highlights a computational transference of techniques between species, institutional settings and domains that is relevant to regulatory considerations for AI development. The paper posits how a significant sector of data innovation – concerning uses on animals – may tend to evade some level of regulatory and ethical scrutiny afforded to human spaces and settings, and as such afford optimisation of these systems beyond our recognition.

Effect of a targeted pain management protocol for the treatment of dermatitis interdigitalis contagiosa in Merino meat sheep in a tilt squeeze chute

IntroductionThe effect of a targeted pain management protocol consisting of sedation and local anesthesia on the stress response to treatment of dermatitis interdigitalis contagiosa (DINCO) was assessed in sheep placed in dorsal recumbency.MethodsBlood cortisol concentrations were measured once a day (Day -3 to 2) and additionally on day 0, six times during the claw treatment (stress model). Twelve healthy sheep (control group; HEALTHY) and 36 sheep with DINCO, randomly allocated to one of three treatment groups, underwent the stress model with or without pain control: the XYLA-IVRA sheep were sedated with 2% xylazine hydrochloride (XYLA) and received retrograde intravenous regional anesthesia (IVRA); the IVRA sheep underwent IVRA and received a placebo instead of sedation; the PLACEBO sheep received placebos for sedation and IVRA. The HEALTHY sheep underwent sham claw treatment and received placebos.Results and discussionThe cortisol concentrations were higher in sheep restrained in dorsal recumbency compared with the cortisol concentrations measured four hours later in standing sheep (HEALTHY 37.2 ± 3.3 ng/ml vs. 18.5 ± 3.3 ng/ml; DISEASED 34.0 ± 1.9 ng/ml vs. 17.6 ± 1.9 ng/ml; p &amp;lt; 0.001). The stress response of XYLA-IVRA (area under the curve; AUC = 34.9 ± 2.6 ng/ml) was reduced compared with the stress response of PLACEBO (AUC = 48.0 ± 2.6 ng/ml, p &amp;lt; 0.01) and HEALTHY sheep (AUC = 46.6 ± 2.5 ng/ml; p = 0.01). While cortisol concentration of XYLA-IVRA and HEALTHY sheep did not increase one day after the stress model (Day 1) compared with the day of the stress model (Day 0), both PLACEBO (47.4 ± 3.3 vs. 35.6 ± 3.1 ng/ml, p = 0.02) and IVRA sheep (39.1 ± 2.8 vs. 28.6 ± 3.1 ng/ml, p = 0.01) had higher cortisol concentrations. The results confirm that fixation in dorsal recumbency in a tilt squeeze chute was a major stressor in sheep. The differences in the cortisol concentration of the PLACEBO sheep versus the XYLA-IVRA sheep during and after the stress model illustrate the effect and necessity of pain management protocols in practice.

A Novel Oral Endoscopic Biopsy Procedure to Obtain Rumen Epithelial Samples.

Most in vivo studies related to ruminal development in calves use invasive techniques involving rumen-fistulated or euthanized animals. In consideration of animal welfare, we developed an oral endoscopic biopsy procedure to allow the obtaining of rumen epithelial samples, thus serving as an alternative for measuring the height and width of rumen papillae in calves in a safe, quick, and efficient manner that allows the slaughtering of calves to be avoided. This procedure was tested on 12 Brangus crossbred calves randomly distributed in two groups, with one fed a meal starter and the other an extruded starter feed. Calves underwent a 12-h fasting period, were restrained in a squeeze chute, administered a dose of atropine, and sedated with xylazine before the oral endoscopic biopsy procedure. A 120 cm long Olympus® oral flexible video endoscope and forceps were used to collect cranial–dorsal sac rumen epithelial tissue samples of approximately 0.5 mm. Endoscopy was successful in all 12 calves and the collected tissue samples were placed in formalin (10%) for further processing for obtaining rumen papillae measurements. Consumption of the extruded starter feed resulted in the increased (p = 0.035) width of rumen papillae. The oral endoscopic biopsy procedure implemented in this study was demonstrated to be successful and is thus an alternative technique for studying rumen epithelial development and morphometric alterations in calf rumen tissue.

Study on the temperament of cows of the Aberdeen Angus cattle breed

The present study examined the temperament of 699 cows of the Aberdeen Angus cattle breed, reared in 14 farms in Bulgaria. It was carried out within the period 2017–2020. The animals subject to the study were between two and eight years old. The temperament was visually evaluated following a scoring system from 1 to 5. The assessment method involved the behavioural reaction of the cows upon manipulation, passing through a chute and fixation into a cattle crush. The temperament of cows reared in two different systems – intensive and semi-intensive farming was compared. The temperament of the Aberdeen Angus cows had an average rate of 2.74 ± 0.04. The cows which had frequent contact with people had a calmer temperament. The manner of rearing (P &amp;lt; 0.001) as well as the age group (P &amp;lt; 0.001) had a significant influence on the parameter examined. The young animals were calmer and got accustomed to working in a crush more easily when they were reared together with cows of different ages.

Strategies for oocyte collection and in vitro embryo production in free-roaming bison herds.

The study was conducted to test the feasibility of protocols for field collection of cumulus–oocyte complexes (COC) for in vitro embryo production (IVP) in wild bison. The study was done with captive wood bison during the anovulatory season. In Experiment 1, the efficiency of transvaginal ultrasound-guided COC collection was compared between bison restrained in a squeeze chute without sedation vs in lateral recumbency after chemical immobilization using a dart gun (n = 8/group). In Experiment 2, a 2 × 2 design was used to examine the effects of superstimulation treatment [single dose of equine chorionic gonodotrophin (eCG) vs multiple doses of follicle stimulating hormone (FSH)] and method of drug administration (manual injection vs field darting) on COC collection and IVP. In Experiment 1, no difference was detected between chute-restrained vs chemically immobilized groups in the time required to complete COC collections, the number of follicles aspirated (11.5 ± 1.9 vs 9.3 ± 1.8; P = 0.4) or the COC recovery rate [COC recovered/follicle aspirated; 58/92 (63%) vs 44/69 (64%); P = 0.9]. In Experiment 2, no differences were detected between superstimulation treatments (eCG vs FSH). The total number of follicles available for aspiration did not differ between manual injection and field darting (23.9 ± 2.7 vs 21.6 ± 1.9; P = 0.4). Compared with the random start unstimulated group, the embryo production rate was higher [18/132 (14%) vs 53/189 (28%); P = 0.04] after wave synchronization and superstimulation. Results suggest that COC collection is equally feasible in a recumbent position after chemical immobilization as those bison restrained in a standing position in a hydraulic chute. Ovarian superstimulation with a single-dose eCG protocol is as effective as a multiple-dose FSH protocol, and field darting is as effective as chute-side administration of superstimulation treatments. The strategies in the present study are ready to be incorporated into field collections in free-roaming bison herds.

Are dairy cows with a more reactive temperament less efficient in energetic metabolism and do they produce more enteric methane?

It remains unknown whether dairy cows with more reactive temperament produce more enteric methane (CH4) and are less bioenergetically efficient than the calmer ones. The objectives of this study were (a) to evaluate the relationship between cattle temperament assessed by traditionally used tests with energetic metabolism and enteric CH4 emissions by crossbred dairy cows; (b) to assess how cows’ restlessness in respiration chambers affects energetic metabolism and enteric CH4 emissions. Temperament indicators were evaluated for 28 primiparous F1 Holstein-Gyr cows tested singly in the handling corral (entrance time, crush score, flight speed, and flight distance) and during milking (steps, kicks, defecation, rumination, and kick the milking cluster off). Cows’ behaviors within respiration chambers were also recorded for each individual kept singly. Digestibility and calorimetry trials were performed to obtain energy partitioning and CH4 measures. Cows with more reactive temperament in milking (the ones that kicked the milking cluster off more frequently) spent 25.24% less net energy on lactation (P = 0.04) and emitted 36.77% more enteric CH4/kg of milk (P = 0.03). Furthermore, cows that showed a higher frequency of rumination at milking parlor allocated 57.93% more net energy for milk production (P < 0.01), spent 50.00% more metabolizable energy for milk production (P < 0.01) and 37.10% less CH4/kg of milk (P = 0.04). Regarding the handling temperament, most reactive cows according to flight speed, lost 29.16% less energy as urine (P = 0.05) and tended to have 14.30% more enteric CH4 production (P = 0.08), as well as cows with a lower entrance time (most reactive) that also lost 13.29% more energy as enteric CH4 (P = 0.04). Temperament and restless behavior of Holstein-Gyr cows were related to metabolic efficiency and enteric CH4 emissions. Cows’ reactivity and rumination in the milking parlor, in addition to flight speed and entrance time in the squeeze chute during handling in the corral, could be useful measures to predict animals more prone to metabolic inefficiency, which could negatively affect the sustainability of dairy systems.

Effects of temperament on body parameters, ovarian structures and inflammatory response in grazing Nellore cows following fixed-time artificial insemination

This study evaluated the associations of temperament with body weight (BW) and body condition score (BCS) change, ovarian structures, and inflammatory response in grazing Nellore cows assigned to a fixed-time artificial insemination protocol. Forty multiparous cows were kept on pasture and offered free-choice access to mineral/vitamin supplementation and fixed-time artificial insemination on d 0. Individual temperament scores (1-5) were assessed in the squeeze chute on d -30, where 1 are animals extremely calm and 5 extremely excitable. Cows with a chute score ≤ 3 were classified as ``calm'', and > 3 as ``excitable''. The BW and BCS were evaluated on days -30, 0 and 30, ovarian structures on days 0 and 14, and blood samples collected on days -30, -11, 0, 7, 14, 21 and 30. Excitable animals tended to have less (P = 0.09) BCS and lose more (P = 0.09) BCS from d -30 to 0. Temperament did not affect (P ≥ 0.12) BW and BW change. Excitable animals tended (P ≤ 0.10) to have smaller dominant follicles, corpus luteum (CL) diameters and CL volumes. Temperament did not affect (P ≥ 0.14) plasma concentrations of haptoglobin and ceruloplasmin, but excitable animals had less (P = 0.04) plasma concentrations of progesterone on days 7 and 14. Thus, excitable cows had less plasma progesterone concentrations and tended to have a greater decrease in BCS and had smaller dominant follicles and CL size.

Habituation of common eland (Taurotragus oryx) to intensive routine handling, and the effect of immunocastration thereon

The temperament of captive common eland (Taurotragus oryx) during handling is crucial for their management, as they have been identified as an ideal antelope for game meat farming, and are well-represented in captive antelope populations world-wide. Generally speaking, common eland are considered undomesticated, and thus maintain their natural prey instincts, making it necessary to habituate them to routine handling. Immunocastration can be implemented as part of the herd management strategy in mixed or single-sex eland groups, and might reduce aggressive behaviour of males by blocking the production of testosterone, thereby improving docility for ease of handling. Within this study, data was collected to determine the influence of routine handling and immunocastration on the temperament of common eland during handling. Twenty-nine common eland were divided into two groups: sub-adults (n = 15; ca. 2 years old; 182.9 ± 59.37 kg) and juveniles (n = 14; ca. 6 months old; 94.18 ± 24.76 kg), and they were routinely handled every two weeks over a four-month period (10 handling events). Within each age group, females, males, and immunocastrated males were present. Immunocastration treatment was administered during the second and fourth handling events (2 mL Improvac®/ animal). During handling, animals were individually driven through the raceway and finally restrained in a squeeze chute, where routine biological samples and measurements were collected. Faecal androgen metabolite (fAM) concentrations were measured for each event, for males only. Each animal was focally sampled for specific behaviours during the handling. A temperament score was obtained by observing the general state of the animal from the point of entering the raceway, until its exit from the squeeze chute. Generalized linear mixed models tested the influence of immunocastration, week, group, fAM concentration, and body weight on the temperament score. Immunocastration did not affect the temperament score, the general state in the squeeze chute, the order of entering the handling system, and the chute exit. However, the temperament score and the state in the squeeze chute improved overtime (with animals being less nervous). Moreover, animals with low temperament scores (calmer) entered the system earlier, and exited the system calmly over the repeated handling period. The results show that routine handling through a raceway and squeeze chute system leads to habituation, and improves the ease of handling in common eland. However, immunocastration did not affect the temperament of the male common eland during handling.

Repeatability Of Temperament Scores In Bunaji And Frieslan-bunaji Crosses

Repeatabilities of temperament scores were estimated by breed, sex, age, weight and body condition in an enclosed weighbridge (method 1) and in a cattle crush (method 2). The model used included animal, scorer, animal x scorer and replicate within scorer effects. The within and between animal variation accounted for 44 and 54%, respectively, for method 1 and 67 and 32%, respectively, of total variation for method 2. Animal x scorer interaction was not significant. For both methods, repeatabilities for temperament scores were 0.56 and 0.54, for method 1 and 0.33 and 0.32, for method 2. Scoring animals in seclusion seems to enhance expression of temperament and hence is more repeatable and reproducible.

Cattle stress and pregnancy responses when imposing different restraint methods for conducting fixed time artificial insemination

Physiological stress responses have been associated with lesser pregnancy rates in beef cattle. Alternative cattle restraint methods have been developed to reduce this negative effect. The objective was to determine if there was a difference in pregnancy rate as a result of fixed-time artificial insemination (FTAI) in Bos taurus females when using a breeding box compared with a squeeze chute for restraining cows when conducting FTAI. There were FTAI treatment regimens imposed on cows and heifers at two separate locations (Virginia Tech University, VT; and R.A. Brown Ranch, RAB) with the FTAI being conducted while animals were restrained in a squeeze chute (n = 169) or a breeding box (n = 162). There was imposing of a 7-day Co-Sync + CIDR pre-breeding treatment regimen. Females were randomly assigned to treatments just prior to breeding. Immediately following breeding, blood was collected using coccygeal venipuncture procedures for assessment of plasma cortisol concentration. Chute and exit scores (1–5) were determined at the time of FTAI. Pregnancy rate, cortisol, chute score, and exit score were analyzed. There was no difference in pregnancy rate between treatments (57 ± 26% and 69 ± 26 %, respectively P = 0.59).There were differences in chute (1.52 ± 0.05 and 1.27 ± 0.05, respectively P < 0.05) and exit (1.26 ± 0.04 and 1.08 ± 0.04, respectively P < 0.05) scores between the two treatment groups. Results from the present study are not conclusive in ascertaining effects of the two types of restraint during FTAI on reproductive efficiency.

PSV-15 Influence of the temperament of water buffaloes on the serum lipid levels

Abstract This study evaluated the effect of the temperament of 75 water buffaloes of three genetic groups (GG: Jafarabadi, Mediterranean, and Murrah; n = 25 for each GG) on serum lipid levels. The animals were classified for temperament through the temperament score (TSc) obtained by the mean of the sum of the scores of the entry time into the squeeze chute (1 to 5: 1=greater time spent for entry, and 5=less time spent for entry) and the exit velocity score (1 to 5: 1=lower speed, and 5=higher speed) calculated after the period of adaptation to the feedlot (d0). The animals were categorized into adequate (ADQ; TSc≤3) or excitable (EXC; TSc &amp;gt;3) temperaments. Blood samples were collected from the jugular vein on days -28, 0, and 84, and evaluated for serum levels of total cholesterol, triglycerides, high-density lipoprotein (HDL), low-density lipoprotein (LDL), and very low-density lipoprotein (VLDL) using colorimetric enzymatic analyses performed by commercial kits. Data were analyzed using MIXED procedure in SAS, considering the GG, temperament, day, and the resulting interactions as fixed effects. The term day was used for repeated measures in time. Correlations were estimated using the CORR procedure in SAS. There were no interactions for the variables evaluated (P ≥ 0.11). ADQ animals showed lower levels of total cholesterol (65.95 vs 70.96mg/dL for ADQ and EXC, respectively; SEM=2.33; P = 0.04) and LDL (26.74 vs 30.40mg/dL for ADQ and EXC, respectively; SEM=1.57; P = 0.02) than EXC animals. There was no effect of temperament for the triglycerides (P = 0.41), HDL (P = 0.47), and VLDL (P = 0.46). Positive correlations were verified between both the TSc and triglycerides (r=0.32; P &amp;lt; 0.01), and TSc and VLDL (r=0.33; P &amp;lt; 0.01). Tendency for a positive correlation was detected between TSc and LDL (r=0.20; P = 0.09). In conclusion, there are differences in serum lipid levels between water buffalo temperaments which deserves further investigation. Supported by FAPESP (#2018/25939-1; #2014/05473-7).

PSV-24 Use of the entry time and exit velocity as tools for the assessment of water buffalo temperament

Abstract The use of the entry time, chute score, and exit velocity as tools for the assessment water buffaloes (WB) temperament were used. Seventy-five non-castrated WB (390±32 days of age; 310±61.27 kg of initial body weight) of 3 genetic groups (GG:Jafarabadi, Mediterranean, and Murrah; n = 25 for each GG) were used. The WB arrived at research center (-28d) and were submitted to 28 days of adaptation period to the feedlot facilities, diet, and handling. On day 0, the temperament variables were collected, namely: entry time into squeeze chute (by chronometer); chute score (5-point scale:1=calm animals; 5=very reactive animals); and, exit velocity (by infrared sensors). Subsequently, blood samples were collected from the jugular vein and analyzed for serum levels of cortisol using radioimmunoassay technique; and, rectal temperature was recorded. The individual temperament score (TSc) was calculated averaging entry time score (5-point scale:1=greater time spent, and 5=less time spent), chute score, and exit velocity score (5-point scale:1=lower speed; 5=higher speed). Data were subjected to a stepwise discriminant analysis (SDA) using the STEPDISC procedure in SAS. The value of P &amp;lt; 0.01 was stipulated to consider and include the variable in the model. The respective data of the selected variables were submitted to multivariate analysis of variance using the GLM procedure in SAS. The GG were added to the model to test the possible effect. Correlation analysis was performed using CORR procedure in SAS. The SDA used three steps and selected only the entry time and exit velocity scores (Table 1). Positive correlations were verified between the TSc and cortisol (r=0.37; P = 0.02), and TSc and rectal temperature (r=0.36; P &amp;lt; 0.01). In conclusion, the entry time and exit velocity may be tools for the assessment of water buffalo temperament and their use should be tested in animals of different categories. Supported by FAPESP (#2018/25939-1; #2014/05473-7).