Changes in Fecal Carriage of Extended-Spectrum ß-Lactamase Producing Enterobacterales in Dutch Veal Calves by Clonal Spread of Klebsiella pneumoniae.

This study aimed to characterize the changes in fecal carriage of Extended-Spectrum ß-Lactamase (ESBL) producing Enterobacterales (ESBL-PE) in a single Dutch veal calves. During the rearing period at the Dutch veal farm, a decrease in fecal carriage of cefotaxime-resistant Escherichia coli isolates was observed after 2 weeks at the veal farm, while an increase of cefotaxime-resistant Klebsiella pneumoniae isolates was demonstrated. E. coli and K. pneumoniae were isolated from rectal swabs collected from 110 veal calves in week 2, 6, 10, 18, and 24 after their arrival at the farm. ESBL-PE isolates were selectively cultured and identified by MALDI-TOF. ESBL genes were characterized by RT-PCR, PCRs, and amplicon sequencing. A total of 80 E. coli and 174 K. pneumoniae strains were isolated from 104 out of 110 veal calves. The prevalence of ESBL-E. coli decreased from week 2 (61%) to week 6 (7%), while an unexpected increase in ESBL-K. pneumoniae colonization was detected in week 6 (80%). The predominant ESBL genes detected in E. coli isolates were bla CTX-M-15 and the non-ESBL gene bla TEM-1a, while in K. pneumoniae bla CTX-M-14 gene was detected in all isolates. Four cefotaxime-resistant K. pneumoniae isolates were randomly selected and characterized in deep by transformation, PCR-based replicon typing, and whole-genome sequencing (WGS). The clonal relatedness of a subgroup of nine animals carrying K. pneumoniae ESBL genes was investigated by Multi Locus sequence typing (MLST). In four ESBL-K. pneumoniae isolates, bla CTX-M-14 was located on IncFIIK and IncFIINK plasmid replicons and the isolates were multi-drug resistant (MDR). MLST demonstrated a clonal spread of ESBL-K. pneumoniae ST107. To the best of our knowledge, this is the first study to report a change in fecal carriage of ESBL-PE over time in the same veal calf during the rearing period.

A Systematic Review of Automatic Health Monitoring in Calves: Glimpsing the Future From Current Practice.

Infectious diseases, particularly bovine respiratory disease (BRD) and neonatal calf diarrhea (NCD), are prevalent in calves. Efficient health-monitoring tools to identify such diseases on time are lacking. Common practice (i.e., health checks) often identifies sick calves at a late stage of disease or not at all. Sensor technology enables the automatic and continuous monitoring of calf physiology or behavior, potentially offering timely and precise detection of sick calves. A systematic overview of automated disease detection in calves is still lacking. The objectives of this literature review were hence: to investigate previously applied sensor validation methods used in the context of calf health, to identify sensors used on calves, the parameters these sensors monitor, and the statistical tools applied to identify diseases, to explore potential research gaps and to point to future research opportunities. To achieve these objectives, systematic literature searches were conducted. We defined four stages in the development of health-monitoring systems: (1) sensor technique, (2) data interpretation, (3) information integration, and (4) decision support. Fifty-four articles were included (stage one: 26; stage two: 19; stage three: 9; and stage four: 0). Common parameters that assess the performance of these systems are sensitivity, specificity, accuracy, precision, and negative predictive value. Gold standards that typically assess these parameters include manual measurement and manual health-assessment protocols. At stage one, automatic feeding stations, accelerometers, infrared thermography cameras, microphones, and 3-D cameras are accurate in screening behavior and physiology in calves. At stage two, changes in feeding behaviors, lying, activity, or body temperature corresponded to changes in health status, and point to health issues earlier than manual health checks. At stage three, accelerometers, thermometers, and automatic feeding stations have been integrated into one system that was shown to be able to successfully detect diseases in calves, including BRD and NCD. We discuss these findings, look into potentials at stage four, and touch upon the topic of resilience, whereby health-monitoring system might be used to detect low resilience (i.e., prone to disease but clinically healthy calves), promoting further improvements in calf health and welfare.

Effects of pre-transport diet, transport duration and transport condition on immune cell subsets, haptoglobin, cortisol and bilirubin in young veal calves.

The aim of this study was to investigate effects of pre-transport diets, transport durations and transport conditions on immune cell subsets, haptoglobin, cortisol and bilirubin of young calves upon arrival at the veal farm. An experiment was conducted with a 2 × 2 × 2 factorial arrangement with 3 factors: 1) provision of rearing milk or electrolytes at the collection center (CC); 2) transport duration (6 or 18 hours) and 3) transport condition (open truck or conditioned truck). Holstein-Friesian and cross-bred calves were used (N = 368; 18 ± 4 days; 45.3 ± 3.3 kg). Blood samples were collected from calves (N = 128) at the collection center, immediately post-transport (T0) and 4, 24, 48 hours, week 1, 3 and 5 post-transport. Blood was analyzed for cortisol, bilirubin, haptoglobin, IgG and IgM. Moreover, cell counts of neutrophils, lymphocytes, monocytes, basophils and eosinophils were measured in blood samples taken at the collection center and T0. In these same blood samples, different lymphocyte populations were characterized by flow cytometry, including CD14+ cells, NK cells, δγ+ T cells, CD8+ cells, CD4+ cells and CD21+ cells. Calves transported in the conditioned truck had higher amounts of white blood cell count (WBC) (Δ = 1.39 × 109/l; P = 0.01), monocytes (Δ = 0.21 × 109/l; P = 0.04), neutrophils (Δ = 0.93 × 109/l; P = 0.003), than calves transported in the open truck regardless, of pre-transport diet or transport duration. The study showed that transport condition and duration influenced parts of the innate immune system of young veal calves. Cortisol, bilirubin and WBC seemed to be connected by similar underlying mechanisms in relation to transport conditions. However, it is unclear which specific pathways in the immune system of young calves are affected by different transport conditions (e.g. temperature, humidity, draught).

Transport of Young Veal Calves: Effects of Pre-transport Diet, Transport Duration and Type of Vehicle on Health, Behavior, Use of Medicines, and Slaughter Characteristics.

The aim of this study was to investigate effects of different early life transport-related factors on health, behavior, use of medicines and slaughter characteristics of veal calves. An experiment was conducted with a 2 × 2 × 2 factorial arrangement with 3 factors: (1) provision of rearing milk or electrolytes before transport, (2) transport duration (6 or 18 h), and (3) type of vehicle (open truck or conditioned truck). The study included male Holstein-Friesian and cross-bred calves (N = 368; 18 ± 4 days; 45.3 ± 3.3 kg). Data on health status of calves were collected at the collection center and at the veal farm until week 27 post-transport. Behavior of calves was recorded during transport and at the veal farm until week 13 post-transport. Use of herd and individual medical treatments was recorded at the veal farm. The prevalence of loose or liquid manure at the veal farm from day 1 until week 3 post-transport was lower in electrolyte-fed calves transported in the conditioned truck compared to electrolytes-fed calves transported in the open truck or milk-fed calves transported in both the conditioned and open truck (Δ = 11% on average; P = 0.02). In comparison with the open truck, calves transported in the conditioned truck had lower prevalence of navel inflammation in the first 3 weeks post-transport (Δ = 3 %; P = 0.05). More milk-fed calves received individual antibiotic treatments compared to electrolyte-fed calves at the veal farm (P = 0.05). In conclusion, the transport-related factors examined in the present study affected health and behavior of calves in the short-term, but there was no evidence for long-term effects. It remains unknown why no long-term effects were found in this study. Perhaps this absence of transport-related effects was due to multiple use of medical treatments in the first weeks at the veal farm. Alternatively, it might be that the collective effects of the transition from the dairy farm to the veal farm, and of the husbandry conditions during the subsequent rearing period, on the adaptive capacity of calves were so large that effects of individual transport-related factors were overruled.

Evaluating Potential Biomarkers of Health and Performance in Veal Calves.

Veal calves undergo many challenges in the early stages of their life. Such challenges, including mixing procedures and transportation of calves to the veal farm, may have a negative influence on growth rate, feed intake, metabolism, immunity and disease susceptibility of calves. As a consequence, many hematological, physiological, metabolic and immunological parameters of stressed calves might be altered on arrival at the veal farm. Some of these response variables might be useful as biomarkers of performance of calves at the veal farm as they might provide information about an ongoing disease process, or may predict future diseases. Biomarkers might be helpful to group and manage calves in different risk categories after arrival. By adopting treatment decisions and protocols on a risk-group or individual basis, it would be possible to improve animal health and reduce both disease incidence and antibiotic use. Moreover, the use of biomarkers might be an economically feasible approach as some of them do not need invasive techniques and others can be measured in blood already taken during routine checks. Previous literature mainly assessed the physiological responses of calves to transportation. However, information on the link between on-farm arrival data and future health and performance of veal calves is limited. This review, therefore, examined a wide range of papers and aimed to identify potential biomarkers of future health and performance.

Individual variation in coping with stress: a multidimensional approach of ultimate and proximate mechanisms.

Ecological studies on feral populations of mice, fish and birds elucidate the functional significance of phenotypes that differ individually in their behavioral and neuroendocrine response to environmental challenge. Within a species, the capacity to cope with environmental challenges largely determines individual survival in the natural habitat. Recent studies indicate that individual variation within a species may buffer the species for strong fluctuations in the natural habitat. A conceptual framework will be presented that is based on the view that individual variation in aggressive behavior can be considered more generally as a variation in actively coping with environmental challenges. Highly aggressive individuals adopt a proactive coping style whereas low levels of aggression indicate a more passive or reactive style of coping. Coping styles have now been identified in a range of species and can be considered as trait characteristics that are stable over time and across situations. The dimension of coping style seems to be independent of an emotionality dimension. Hence, in the analysis of the proximate mechanisms of stress and adaptation, one has to consider the possibility that the mechanisms which determine the type of stress response might be independent from those underlying the magnitude of the response. The two coping styles differ in a number of important neurobiological and neuroendocrine systems. For example, proactive males differ significantly from reactive males in the homeostatic control of serotonergic activity resulting in completely opposite dose response relationships of various serotonergic drugs. The results so far show that proactive coping is characterized by a strong inhibitory control of the 5-HT neuron via its somatodendritic 5-HT(1A) autoreceptor. It is hypothesized that the regulation of serotonin release is causally related to coping style rather than emotionality. Understanding the functional individual variation as it occurs in nature and the underlying neurobiology and neuroendocrinology is fundamental in understanding individual vulnerability to stress related disease.

Response to LPS in female offspring from sows treated with cortisol during pregnancy.

Prenatal stress has been shown to program responsiveness of the hypothalamus-pituitary-adrenal axis (HPA-axis) and behavior in offspring. In pig husbandry, sows are exposed to stressful conditions during gestation. Previously, cortisol treatment of pregnant sows has been shown to alter stress responsiveness and immunological parameters in their piglets. In the present study, we explored whether cortisol treatment of pregnant sows affects the offspring's response to an inflammatory stimulus. Sows were treated orally with cortisol either during the first, second, or third period of gestation, or received a placebo during this period. At 8 weeks of age, female offspring were injected intravenously with lipopolysaccharide (LPS). Offspring of sows that received cortisol during the first and third period of gestation showed a higher fever response to LPS. Cortisol treatment of sows during gestation did not affect offspring's response to LPS with regard to their cortisol response. LPS-induced sickness behavior, which was measured as the latency time in a human approach test, appeared to recover more quickly in offspring from sows that received cortisol during the second period of gestation. These results suggest that prenatal cortisol exposure programs responsiveness to inflammatory stimuli in female piglets.

Evaluation of oral administration of cortisol as a model for prenatal stress in pregnant sows.

OBJECTIVE: To design a treatment that increases plasma corticosteroid concentrations to mimic prenatal stress in pregnant sows. ANIMALS: 24 pregnant sows. PROCEDURE: Sows were assigned to 1 of 4 treatment groups; treatment consisted of twice-daily oral administration of a placebo or 20, 60, or 180 mg of hydrocortisone acetate (HCA)/sow from 7 to 11 weeks of gestation. Blood and saliva samples for determination of cortisol concentrations were obtained hourly on treatment days 3 and 25 and twice weekly for the remainder of the treatment period. The WBC, neutrophil, and lymphocyte counts and concentrations of interleukin (IL)-2 and IL-4 were determined on 4 days during treatment. Litter characteristics were recorded. RESULTS: Plasma and salivary cortisol concentrations were significantly increased in sows that received 60 or 180 mg of HCA (0.30 to 0.37 mg/kg and 0.95 to 1.15 mg/kg, respectively), compared with control sows. Except for the second day of treatment, the number of WBCs and the IL-2:IL-4 ratio did not differ among treatment groups. The neutrophil-to-lymphocyte ratio was significantly higher in sows that received 180 mg of HCA. Gestation duration was significantly shorter in sows that received 180 mg of HCA. CONCLUSIONS AND CLINICAL RELEVANCE: Oral administration of 60 mg of HCA is suitable to increase plasma and salivary cortisol concentrations in pregnant sows in a controlled manner to concentrations comparable to concentrations detected after psychologic stressors. This model seems to be suitable to study the effects of increased maternal corticosteroid concentrations on young pig behavior, physiologic variables, and development.