Investigation of the physiological, behavioral, and biochemical responses of cattle to restraint stress

Management of dairy heifers: Can operant conditioning be an effective and feasible tool to decrease stress and ease animals' close contact and handling?

Besides health monitoring, a regular check of dairy heifers' growth rate is desirable, but it is rarely done because procedures that require restraint and handling can be associated with substantial stress for both animals and farmers. Inexperienced heifers, especially if they are highly responsive to humans, may find restraint and handling potentially aversive. This study investigated whether training heifers of different age and responsiveness toward humans (RTH), through operant conditioning, could reduce stress in animals, ease close contact and handling, and be feasible in terms of farmers' effort. We assessed 60 Holstein heifers of 2 age classes (young, n = 29, 291 ± 39 d; old, n = 31, 346 ± 62 d) according to the avoidance distance test and classified them as confident (n = 20), neutral (n = 21), or nonconfident (n = 19). Half of the heifers of each age and RTH class were trained (n = 29), whereas the other half was not (n = 31). The trained heifers were subjected to target training for 8 sessions and positively reinforced with feed to allow being touched on the muzzle, rump, and perineum. If a heifer refused positive reinforcement, the trainer stepped back as negative reinforcement. In the last week of the experiment, the effect of training on the reaction to handling was assessed in all heifers. We measured heart rate, root mean square of successive interbeat interval differences (RMSSD), and fecal cortisol metabolites (FCMet). The presence of behavioral distress signs was recorded as well. The avoidance distance test was performed a second time 24 h after the measuring session. All of the trained heifers, regardless of RTH class, successfully accomplished the target training task in 6 sessions, each spending on average 25.3 s per session. All of the trained heifers allowed touches on the rump and perineum at the end of the fourth session. Training nonconfident heifers required more time compared with the others. Trained heifers showed higher RMSSD than nontrained heifers (14.2 vs. 16.9 ms, respectively), indicating a lower vagal tone, and thus, a slightly lower stress level than nontrained heifers. Training did not lead to differences in HR, FCMet, or presence of stress behavioral signs. Nonconfident heifers had the highest mean baseline FCMet values compared with neutral and confident heifers (38.4 vs. 30.3 vs. 29.1 ng/g, respectively). Nonconfident heifers also showed the lowest value of FCMet 12 h after the measuring session (36.7 vs. 44.6 vs. 49.7 ng/g), likely due to a decreased responsiveness of the adrenal gland to a stressor. The average avoidance distance decreased between the beginning and the end of the experiment, especially for neutral and nonconfident heifers, regardless of whether they were trained or not. These results show how using operant conditioning on some heifers not only decreased their vagal tone, but also reduced the responsiveness to humans of all the animals, trained and not trained; in the latter case, this reduction was through nonassociative learning, such as habituation.

Comparative Assessment of the Stress Response of Cattle to Common Dairy Management Practices

While studies have been conducted examining the stress response of dairy cattle to individual acute and chronic stressors, the results are difficult to compare due to differences in study design and analysis methods. The aim of the present study was to conduct a comparative assessment of the impact of eight common stimuli: artificial insemination (AI), embryo transfer (ET), morning milking (MM), evening milking (EM), veterinary examination (VE), ultrasound examination (US), hoof trimming (HT), and natural breeding (NB) on the hypothalamic-pituitary-adrenal axis and milk production of 24 Holstein-Friesian cattle. After random allocation into control and treatment groups, a total of five blood samples were collected 40 min (Ba1) and 20 min (Ba2) prior to stimulus application, immediately following the stimulus (St), as well as 20 min (Re1) and 40 min (Re2) post-stimulus. A comparison between the overall serum cortisol concentrations in the treatment groups showed a significant difference between HT to AI (p = 0.006), ET (p = 0.010), MM (p = 0.021), VE (p = 0.009), EM (p = 0.007), and US (p = 0.010), except for NB (p = 0.542). There is no significant difference between the control groups (p > 0.05). The stimuli HT (p < 0.001) and NB (p < 0.001) showed significant increases in cortisol following stimulus application, and the levels failed to decrease significantly by sample Re2. No significant differences in daily milk yield (kg) were measured amongst the tested stimuli (p = 0.472) nor amongst the groups 'Control', 'Treatment' and 'no stimulus' (p = 0.350). In conclusion, when factors such as increased physical activity, novel social interaction, sexual arousal, and a more intense restriction of movement are present, the animal's perceived controllability and predictability might decrease, affecting the animal's response to stress. Treatments carried out while animals are restrained in a headlock while remaining within their regular group likely result in a less intense activation of the HPA axis.

Signaling differences in peripheral blood mononuclear cells of high and low vaccine responders prior to, and following, vaccination in piglets

Individual variability in responses to vaccination can result in vaccinated subjects failing to develop a protective immune response. Vaccine non-responders can remain susceptible to infection and may compromise efforts to achieve herd immunity. Biomarkers of vaccine unresponsiveness could aid vaccine research and development as well as strategically improve vaccine administration programs. We previously vaccinated piglets (n = 117) against a commercial Mycoplasma hyopneumoniae vaccine (RespiSure-One) and observed in low vaccine responder piglets, as defined by serum IgG antibody titers, differential phosphorylation of peptides involved in pro-inflammatory cytokine signaling within peripheral blood mononuclear cells (PBMCs) prior to vaccination, elevated plasma interferon-gamma concentrations, and lower birth weight compared to high vaccine responder piglets. In the current study, we use kinome analysis to investigate signaling events within PBMCs collected from the same high and low vaccine responders at 2 and 6 days post-vaccination. Furthermore, we evaluate the use of inflammatory plasma cytokines, birthweight, and signaling events as biomarkers of vaccine unresponsiveness in a validation cohort of high and low vaccine responders. Differential phosphorylation events (FDR < 0.05) within PBMCs are established between high and low responders at the time of vaccination and at six days post-vaccination. A subset of these phosphorylation events were determined to be consistently differentially phosphorylated (p < 0.05) in the validation cohort of high and low vaccine responders. In contrast, there were no differences in birth weight (p > 0.5) and plasma IFNγ concentrations at the time of vaccination (p > 0.6) between high and low responders within the validation cohort. The results in this study suggest, at least within this study population, phosphorylation biomarkers are more robust predictors of vaccine responsiveness than other physiological markers.

Kinome Analysis of Cattle Peripheral Lymph Nodes to Elucidate Differential Response to Salmonella spp

Salmonella spp., contained within the peripheral lymph nodes (PLNs) of cattle, represents a significant source of contamination of ground beef. Herein is the first report where species-specific kinome peptide arrays designed for bovine biology were used to further the understanding of Salmonella spp. within these PLNs. For the purpose of this research, multiple comparisons of sub-iliac lymph nodes were made to include nodes from feedlot cattle that were infected with Salmonella spp. to those that were non-infected; seasonal differences in feedlot cattle harvested in either August or January; cull dairy cows compared to feedlot cattle; and PLNs from cattle experimentally inoculated with Salmonella spp. versus naturally infected animals. The first comparison of Salmonella-positive and -negative PLNs found that considering the kinotypes for these animals, the major distinguishing difference was not the presence or absence of Salmonella spp. in the PLNs but the concentration. Further, the majority of pathways activated were directly related to immune responses including innate immunity, thus Salmonella spp. within the PLNs activates the immune system in that node. Results from the comparison of feedlot cattle and cull dairy cows suggests that a Salmonella spp.-negative animal, regardless of type, has a more consistent kinome profile than that of a Salmonella spp.-positive animal and that the differences between feedlot and cull dairy cattle are only pronounced when the PLNs are Salmonella spp. positive. PLNs collected in the winter showed a much more consistent kinome profile, regardless of Salmonella status, suggesting that in the winter these cattle are similar, and this is not affected by the presence of Salmonella spp., whereas significant variability among kinotypes was observed for PLNs collected in the summer. The most distinct clustering of kinotypes observed in this study was related to how the animal was infected with Salmonella spp. There were significant differences in the phosphorylation state of the immune response peptides between experimentally and naturally infected animals, suggesting that the immune system is activated in a significantly different manner when comparing these routes of infection. Increasing our understanding of Salmonella spp. within cattle, and specifically within the PLNs, will ultimately help design effective pre-harvest intervention strategies as well as appropriate experimentation to validate those technologies.

Quality of Death in Fighting Bulls during Bullfights: Neurobiology and Physiological Responses

During bullfights, bulls undergo physiometabolic responses such as glycolysis, anaerobic reactions, cellular oedema, splenic contraction, and hypovolemic shock. The objective of this review article is to present the current knowledge on the factors that cause stress in fighting bulls during bullfights, including their dying process, by discussing the neurobiology and their physiological responses. The literature shows that biochemical imbalances occur during bullfights, including hypercalcaemia, hypermagnesaemia, hyperphosphataemia, hyperlactataemia, and hyperglycaemia, associated with increased endogenous cortisol and catecholamine levels. Creatine kinase, citrate synthase, and lactate dehydrogenase levels also increase, coupled with decreases in pH, blood bicarbonate levels, excess base, partial oxygen pressure, and oxygen saturation. The intense exercise also causes a marked decrease of glycogen in type I and II muscle fibres that can produce myoglobinuria and muscular necrosis. Other observations suggest the presence of osteochondrosis. The existing information allows us to conclude that during bullfights, bulls face energy and metabolic demands due to the high intensity and duration of the exercise performed, together with muscular injuries, physiological changes, and high enzyme concentrations. In addition, the final stage of the bullfight causes a slow dying process for an animal that is sentient and conscious of its surroundings.

Development of enzyme immunoassay for chromogranin A (CgA) and profiling of plasma CgA concentrations in the cow

The objectives of this study were to establish and characterize a homologous immunoassay for bovine chromogranin A (bCgA) and to profile plasma bCgA concentrations during early pregnancies. We synthesized oligopeptide corresponding to the amino acid sequence 341-355 of bCgA for immunizing rabbits and peptide corresponding to the amino acid sequence 336-365 of bCgA for both a biotinylated tracer and reference standards. Recombinant bCgA protein was also generated in Escherichia coli lysate. Dose-dependent displacement curves were obtained from 1 to 1,000 nM of the reference standards. The displacement curves showed a good relationship between the reference standards of the synthetic peptide and the serially diluted plasma sample or recombinant bCgA protein generated in the present study. The assay sensitivity defined as the value of two standard deviations below the zero standard was calculated as 0.46 nM. The intraassay and interassay coefficients of variation were 6.48% and 13.4%, respectively. Changes in the plasma bCgA concentrations in early pregnancies undulated in nonpregnant animals. The results of the present study suggest that assaying plasma bCgA concentrations could be utilized as measures to evaluate the physiological status of cattle.

Researching Human-Cattle Interaction on Rangelands: Challenges and Potential Solutions

Simple Summary

Research investigating the influence of human-animal interactions on beef cattle production and welfare often occurs during stress-inducing contexts, such as restraint and transport. Given that beef cattle which graze on expansive rangelands do not frequently interact with humans, assessment of animal response to humans may be inaccurate if they are only recorded during such stressful context. Future research aimed at identifying the causes and impacts of individual human–cattle relationships may consider conducting experiments while the cattle are in a low stress context, such as while ruminating, resting, or, grazing. By adapting methods used to research wildlife response to humans, researchers may be able to better understand how animal personality and previous experience can influence cattle production and welfare.

Abstract

Human-animal interaction (HAI) research spans across many scientific fields and animal taxa. For livestock species, HAI research tends to focus on animals that are managed in close proximity with humans such as poultry, dairy cattle, and swine. Given the nature of rangeland cattle production, HAI research with beef cattle often occurs in and around the processing environment. This high arousal context may skew behavioral and physiological responses by the animals due to the potentially negative interaction. The aim of this review is to describe cattle production on rangelands, examine the considerations and limitations of current HAI research used to evaluate interaction quality or traits of rangeland cattle, identify contexts in which rangeland cattle interact with humans, and provide recommendations for improving future HAI research with rangeland cattle. Current research delineating individual differences in response to humans by beef cattle occur during routine husbandry and management on rangelands (pragmatic) and in a research context (experimental). Human-cattle interactions can be distinguished based on the quality and goal of the interaction into four broad categories: human presence, human approach, human contact, and restraint. Limitations of HAI research with rangeland cattle are identified and reconciled by recommendations for HAI research that can take place outside of the processing environment (i.e., while cattle are ruminating, resting or grazing on rangelands).

Effects of positive reinforcement training for heifers on responses to a subcutaneous injection

Cattle are subjected to routine procedures that require restraint and close contact to humans, which are both potentially aversive to the animal. Positive reinforcement training techniques may affect how animals perceive and respond to these procedures. The objectives of the current study were to describe a positive reinforcement regimen used to train cattle to stand still for a sham injection, and to assess the effects of this training on the responses to an actual injection. Eight "agency" heifers were trained, over an average of 85 ± 4.6 sessions, with positive reinforcement (i.e., animals received a grain reinforcer for desired behaviors) to enter a headlock, and they were habituated with counterconditioning and desensitization to a sham injection (i.e., animals were gradually exposed to the sensation of the sham injection, paired with access to grain). The headlock remained open at all times to allow heifers to leave. Eight "habituation" heifers were exposed to the treatment area and headlock for an equal number of sessions and duration as agency heifers, and 7 "naïve" heifers were provided no exposure to the treatment area. Once agency heifers tolerated the sham injection, all animals received a 1-mL subcutaneous injection of 0.9% NaCl while in the head lock (habituation and naïve heifers were locked in but agency heifers were free to withdraw). Immediate responses to the injection, starting with tenting of the skin, were video recorded and summarized as a reactivity score, which included the number of steps, head tosses, and backing-up movements; we also recorded the latency to approach the treatment area and headlock for 3 d after the injection. Of the agency heifers, 5 remained standing for the actual injection, whereas 3 heifers moved out of the headlock for a brief period (1, 3, and 5 s, respectively). Habituation heifers had a higher reactivity score [17.5 (10.5-28); median (IQR)] than agency [6 (2-13.5)] and naïve heifers [6 (5-7)]. Averaged over the 3 d after injection, agency heifers showed lower latencies to come to the treatment area [8.7 (7.2-24.2) s] than did habituation [50.5 (28-60) s] and naïve [53.7 (18-60) s] heifers. Agency heifers voluntarily entered the headlock within 1.3 (1-1.5) s but, with one exception, none of the other heifers did so within the allowed 15 s. These results indicate that dairy heifers can be trained with positive reinforcement and counterconditioning to voluntarily accept a painful procedure, and that training can reduce avoidance behaviors during and after the procedure.

MicroRNAs as Biomarkers for Animal Health and Welfare in Livestock

MicroRNAs (miRNAs) are small and highly conserved non-coding RNA molecules that orchestrate a wide range of biological processes through the post-transcriptional regulation of gene expression. An intriguing aspect in identifying these molecules as biomarkers is derived from their role in cell-to-cell communication, their active secretion from cells into the extracellular environment, their high stability in body fluids, and their ease of collection. All these features confer on miRNAs the potential to become a non-invasive tool to score animal welfare. There is growing interest in the importance of miRNAs as biomarkers for assessing the welfare of livestock during metabolic, environmental, and management stress, particularly in ruminants, pigs, and poultry. This review provides an overview of the current knowledge regarding the potential use of tissue and/or circulating miRNAs as biomarkers for the assessment of the health and welfare status in these livestock species.

PARAMETERS FOR IDENTIFYING FAILURE OF PASSIVE TRANSFER IN SITATUNGA (TRAGELAPHUS SPEKII)

Failure of passive transfer of immunity (FPT) leads to increased calf morbidity and mortality and requires intensive, time-sensitive, and often expensive management for nondomestic ruminants. Without species-specific information with which to make informed decisions, neonatal data from domestic ruminants are often extrapolated to nondomestic zoo-housed species. To date, there have been no studies evaluating FPT in sitatunga (Tragelaphus spekii). The goal of the present study was to establish parameters to characterize adequate passive transfer in sitatunga calves and compare them to published reference intervals in other species. Medical records of 22 sitatunga calves (12 female, 10 male) were reviewed. Seventeen of these calves were defined as "healthy," having survived at least 60 days without colostrum administration or a plasma transfusion. Calf weight, serum glucose, serum gamma-glutamyl transferase (GGT), total protein (TP), globulin concentrations, and results of a zinc sulfate turbidity test (ZSTT) were noted where possible. Mean birth weight of healthy calves at 24 hr was 4.5 kg (range: 3.76.5 kg, n = 12). The mean blood glucose in healthy calves was 152 mg/dl (range: 80-182, n = 16), mean serum TP concentration was 5.9 g/dl (range: 4.9-7.5, n = 16), mean serum globulin concentration was 3.3 g/dl (range: 1.7-4.7, n = 17), and mean serum GGT concentration was 466 U/L (range: 91-1901, n = 16). A ZSTT was performed for 10 healthy calves, resulting in four negative ZSTT results despite having no clinical signs of FPT and the calves having been observed nursing before testing. Sitatunga appear to have lower values for normal FPT parameters than those developed for domestic cattle. This study illustrates the difficulty of cross-species comparisons, as even closely related species can vary greatly in biologic parameters.

From Beef to Bees: High-Throughput Kinome Analysis to Understand Host Responses of Livestock Species to Infectious Diseases and Industry-Associated Stress

Within human health research, the remarkable utility of kinase inhibitors as therapeutics has motivated efforts to understand biology at the level of global cellular kinase activity (the kinome). In contrast, the diminished potential for using kinase inhibitors in food animals has dampened efforts to translate this research approach to livestock species. This, in our opinion, was a lost opportunity for livestock researchers given the unique potential of kinome analysis to offer insight into complex biology. To remedy this situation, our lab developed user-friendly, cost-effective approaches for kinome analysis that can be readily incorporated into most research programs but with a specific priority to enable the technology to livestock researchers. These contributions include the development of custom software programs for the creation of species-specific kinome arrays as well as comprehensive deconvolution and analysis of kinome array data. Presented in this review are examples of the application of kinome analysis to highlight the utility of the technology to further our understanding of two key complex biological events of priority to the livestock industry: host immune responses to infectious diseases and animal stress responses. These advances and examples of application aim to provide both mechanisms and motivation for researchers, particularly livestock researchers, to incorporate kinome analysis into their research programs.

Kinome Analysis of Honeybee (Apis mellifera L.) Dark-Eyed Pupae Identifies Biomarkers and Mechanisms of Tolerance to Varroa Mite Infestation

The mite Varroa destructor is a serious threat to honeybee populations. Selective breeding for Varroa mite tolerance could be accelerated by biomarkers within individual bees that could be applied to evaluate a colony phenotype. Previously, we demonstrated differences in kinase-mediated signaling between bees from colonies of extreme phenotypes of mite susceptibility. We expand these findings by defining a panel of 19 phosphorylation events that differ significantly between individual pupae from multiple colonies with distinct Varroa mite tolerant phenotypes. The predictive capacity of these biomarkers was evaluated by analyzing uninfested pupae from eight colonies representing a spectrum of mite tolerance. The pool of biomarkers effectively discriminated individual pupae on the basis of colony susceptibility to mite infestation. Kinome analysis of uninfested pupae from mite tolerant colonies highlighted an increased innate immune response capacity. The implication that differences in innate immunity contribute to mite susceptibility is supported by the observation that induction of innate immune signaling responses to infestation is compromised in pupae of the susceptible colonies. Collectively, biomarkers within individual pupae that are predictive of the susceptibility of colonies to mite infestation could provide a molecular tool for selective breeding of tolerant colonies.

Effects of auditory and visual stimuli on glucose metabolism in Holstein dairy cattle

Background

Standardization of the intravenous glucose tolerance test (ivGTT) in cattle has received little attention despite its widespread use to monitor glucose metabolism. The impact of management practices including several sensorial stimuli on test responses has not yet been described in young cattle. The objective of this study was to analyze the effects of noise exposure, and visual food stimuli in combination with physical restraint on ivGTT and insulin traits in Holstein cattle. A total of 108 ivGTT (6 tests per animal) were performed in bulls (n = 6), steers (n = 6), and heifers (n = 6) aged 312 to 344 days. The main parameters analyzed for glucose and insulin included: basal concentration (G0, Ins0), maximum concentration (GMAX, InsMAX), and final concentration at 63 min (G63, Ins63), glucose and insulin area under the curve (GAUC, InsAUC), and glucose half-life time (GHLT). Noise stimuli were induced by playing rock music at approximately 90 dB either before (NI) or immediately after glucose injection (NII). Visual food stimuli were induced by feeding the neighboring animals while the tested animal was restrained in a headlock.

Results

Almost all glucose and insulin traits were affected by gender (P< 0.05) whereas the factor with least impact on ivGTT was NI. InsMAX and InsAUC were affected (P < 0.002) by all factors analyzed. GHLT and G63 were affected by gender and noise with higher values in bulls when compared to steers and heifers. Furthermore, InsAUC and InsMAX values derived from NII significantly differed in bulls when compared to steers and heifers. Significantly higher values for G0 (P < 0.001), InsMAX (P < 0.001) and InsAUC (P = 0.001) were observed when exposed to the visual food stimulus whereas GMAX (P = 0.02) and GAUC (P = 0.04) decreased. Higher Ins63 values were observed in bulls exposed to the visual food stimulus when compared to heifers.

Conclusions

Short-term exposure to noise and visual food stimuli might lead to variations in glucose metabolism and insulin secretion which emphasizes the necessity to avoid practices involving auditory or visual stimuli prior to or during the conduction of an ivGTT.

Branding Practices on Four Dairies in Kantale, Sri Lanka

Simple Summary

Branding cattle with hot irons is a painful procedure, inflicting severe burns that take weeks to heal. Although Sri Lanka prohibits hot-iron branding, the practice is still common in some areas of the country but has not been described. We observed branding practices on four smallholder farms and identified welfare concerns and challenges impeding adoption of alternative methods of identification, such as ear tags. Farmers used multiple irons to mark their initials and, in some cases, their address, with the largest brands extending across the ribs and hip. Farmers did not consider ear tags a viable alternative to hot-iron branding because of issues with security and tag retention. Hot-iron branding raises serious animal welfare concerns and efforts to introduce more welfare-friendly alternatives are needed.

Abstract

Hot-iron branding is illegal in Sri Lanka, but is still commonly used to identify dairy herds in extensive farming systems, which are primarily located in the country’s Dry Zone. Despite the negative welfare implications of this practice, there is no written documentation of branding in this region. We observed branding on four smallholder farms in Kantale, Eastern Province to understand the welfare implications associated with the procedure and challenges limiting the uptake of more welfare-friendly alternatives, such as ear tagging. Areas of welfare concern included the duration of restraint, the size and location of the brand, and the absence of pain relief. Animals were restrained with rope for an average duration of 12 min (range 8–17 min). Farmers used multiple running irons to mark their initials and, in some cases, their address, with the largest brands extending across the ribs and hip. Three farmers applied coconut or neem oil topically to the brand after performing the procedure. No analgesics were given before or after branding. Farmers reported that poor ear tag retention in extensive systems and theft were the main factors impeding the uptake of alternative forms of identification. Branding is also practiced as part of traditional medicine in some cases. Given the clear evidence that hot-iron branding impairs animal welfare and there is no evidence that this can be improved, alternative identification methods are needed, both in Sri Lanka, as well as in other countries engaging in this practice.

A new tool for studying waterfowl immune and metabolic responses: Molecular level analysis using kinome profiling

Here, we describe the design of an Anas-specific kinome peptide array that can be used to study the immunometabolic responses of mallard and American black duck to pathogens, contaminants, and environmental stress. The peptide arrays contain 2,642 unique phosphorylate-able peptide sequences representing 1,900 proteins. These proteins cover a wide array of metabolic and immunological processes, and 758 Gene Ontology Biological processes are statistically significantly represented on the duck peptide array of those 164 contain the term "metabolic" and 25 "immune." In addition, we conducted a comparison of mallard to American black duck at a genetic and proteomic level. Our results show a significant genomic and proteomic overlap between these two duck species, so that we have designed a cross-reactive peptide array capable of studying both species. This is the first reported development of a wildlife species-specific kinome peptide array.

Technological advances for interrogating the human kinome

There is increasing appreciation among researchers and clinicians of the value of investigating biology and pathobiology at the level of cellular kinase (kinome) activity. Kinome analysis provides valuable opportunity to gain insights into complex biology (including disease pathology), identify biomarkers of critical phenotypes (including disease prognosis and evaluation of therapeutic efficacy), and identify targets for therapeutic intervention through kinase inhibitors. The growing interest in kinome analysis has fueled efforts to develop and optimize technologies that enable characterization of phosphorylation-mediated signaling events in a cost-effective, high-throughput manner. In this review, we highlight recent advances to the central technologies currently available for kinome profiling and offer our perspectives on the key challenges remaining to be addressed.