Training Laboratory Rabbits to Refine Routine Husbandry Procedures

Non-aversive handling and training techniques for laboratory animals are required to facilitate experimental and routine husbandry procedures, improving both animal welfare and scientific quality. Clicker training was utilized to develop training protocols for rabbits to refine stressful routine husbandry procedures usually associated with lifting (i.e., being picked up from the floor)/restraining (i.e., being held in the arms of a human) them. Thirteen female New Zealand White rabbits were trained over three weeks. All rabbits learned the predefined goal behaviors: they followed the target stick, jumped onto the weighing scale, entered a transport box, and reared while placing their front paws onto the trainer's hand. In addition, ten animals jumped from the floor onto the sitting trainer's lap and allowed the trainer to lift their paws off the surface while sitting on the trainer's lap. For some individuals, the protocols had to be adapted by additional interim steps. At the end of the training, the rabbits reliably showed the expected goal behaviors, even after short and long training breaks. With few exceptions, a familiar person other than the trainer could elicit the goal behaviors from the rabbits (generalization), though further sessions were required for generalization. In the voluntary approach test, the rabbits preferred interacting with the trainer in the 1st trial but spent as much time with an unfamiliar person as with the trainer in the 2nd trial. The behavioral observations suggested that picking the rabbits up with the transport box, as described in the protocol, instead of restraining them with the scruff of their neck and lifting them on the arm, was less aversive. All in all, the training protocols were feasible and can serve as a refinement strategy in laboratory animal facilities. In the interest of animal welfare, the training protocols should be applied wherever possible.

Academics meet practitioners: Interactive exchange instead of consuming knowledge on dairy calving management

Consensus on optimal calving management is difficult to achieve among veterinarians. Some of this discordance may stem from asymmetry between the literature written by subject matter experts (SME) and the knowledge, attitude and practice (KAP) of non-SMEs and veterinary practitioners. Hence, the objective of this study was to assess how veterinary practitioners KAPs in calving management compared with the findings in the literature. An online questionnaire survey was conducted prior to a World Buiatrics Congress by delegates (n = 80) who attended a workshop on calving management at which the outcomes of the latter were recorded. The responses from the questionnaire and the consensus from the workshop were compared and these were compared with the literature on calving management, specifically, prediction of calving, assistance at calving and farmer training in calving management. In general, there was good agreement between the aggregated individual responses to the questionnaire and the consensuses from the workshop. The suggested methods of predicting calving were well aligned between practitioners and those researched in the literature but practitioners tended to emphasize more practical aspects of prediction while the literature tends to focus more on the effectiveness of various predictor devices. Practitioners tended to recommend a later time of calving assistance than that recommended in the recent literature though they did also emphasize the importance of calving progress. The majority of practitioners conducted informal (at calving) calving training focusing on time of intervention, welfare-friendly intervention and delivery of a live healthy calf. However, the educational literature recommends a formal training approach as being more effective. These findings indicate that practitioners may benefit from continuing professional education on the scientific merits/demerits of calving prediction devices, current best practice on intervention timing during calving and formal methods of farmer training on calving management.

Why workshops work: Examining the efficacy of training trainers to train goats

Experimental procedures involving farm animals are often associated with stress due to restraining. Stress can be reduced through use of positive reinforcement training, which then serves as refinement according to the 3Rs principles. Trainer skills, however, may influence the feasibility and success of animal training. The potential influence of trainer skills as well as the education of animal trainers are rarely described in literature but are necessary information for the implementation of positive reinforcement training as a refinement measure. To investigate the effect of educational programmes on animal trainers, we compared the training success of two groups of participants in training goats to elicit a behaviour that would allow simulated venipuncture. One group was educated in a two-day workshop while the other was provided with specific literature for self-instructed learning. Training success was evaluated using an assessment protocol developed for this study. A greater training success in the WORKSHOP GROUP, reflected by objective and subjective measures, was clearly supported statistically. In addition, 73 versus only 13% of the participants of the WORKSHOP GROUP and the self-instructed BOOK GROUP, respectively, stated that they could completely implement the knowledge gained in the course of this study. Our results indicate that more intensively educated trainers can train animals more successfully. In conclusion, if animal training is implemented as refinement, animal caretakers should receive instruction for positive reinforcement training.

Residue Concentrations of Cloxacillin in Milk after Intramammary Dry Cow Treatment Considering Dry Period Length

Dry cow treatment with an intramammary antibiotic is recommended to reduce the risk of mastitis at the beginning of the next lactation. The dry period may be shortened unintentionally, affecting antibiotic residue depletion and the time when residues reach concentrations below the maximum residue limit (MRL). The objective of this study was to evaluate residue depletion in milk after dry cow treatment with cloxacillin, considering dry periods of 14 (G14d), 21 (G21d), and 28 d (G28d). Overall, fifteen cows with 60 udder quarters were included in the study. For each cow, three of the udder quarters were treated with 1000 mg cloxacillin benzathine (2:1) on d 252, d 259, and d 266 of gestation; one quarter was left untreated. Milk samples were drawn until 20 DIM and milk composition, somatic cell count and cloxacillin residues were analyzed. The HPLC-MS/MS revealed different excretion kinetics for the compounds cloxacillin and cloxacillin benzathine (1:1). All cows showed a cloxacillin and cloxacillin benzathine (1:1) concentration below the MRL of 30 µg/kg after 5 d. In the udder quarters of G21d and G28d, the cloxacillin concentration was already below the MRL at first milking after calving. The cloxacillin benzathine (1:1) concentration in the milk of G28d, G21d, and G14d fell below 30 µg/kg on the 5th, 3rd, and 5th DIM, respectively. Shortening the dry period affects residue depletion after dry cow treatment with cloxacillin. The risk of exceeding the MRL, however, seems low, even with dry periods shorter than 14 d.

Detection of Hypoglycin A and MCPrG Metabolites in the Milk and Urine of Pasture Dairy Cows after Intake of Sycamore Seedlings

Hypoglycin A (HGA), methylenecyclopropylglycine (MCPrG), hypoglycin B (HGB), and γ-glutamyl-α-(methylenecyclopropyl) glycine (γ-glutamyl-MCPrG) are secondary plant metabolites occurring in sycamore maple (Acer pseudoplatanus) as well as several other Sapindaceae (e.g., Blighia sapida). By interfering with energy metabolism, they may cause severe intoxication in humans and other species. However, to date, there is not enough data available concerning the intake, metabolism, or excretion of sycamore maple toxins in dairy cows. In May 2022, five cows were observed over four days, when they had first access to a pasture with two sycamore maples. Grazing of their seedlings that grew numerously in between the pasture plants was monitored by direct observation. Milk samples were drawn both from individual cows and from the bulk tank. Spontaneous urine samples were collected from all cows on day 3 after access to the pasture. Seedlings (100 g) were sampled on the pasture and analyzed, together with milk and urine samples, for sycamore toxins and their metabolites using liquid chromatography-tandem mass spectrometry and liquid chromatography-high-resolution mass spectrometry. Cows ingested sycamore seedlings while grazing. Values of HGA in milk were below the limit of quantification. However, metabolites of HGA and MCPrG were detected in individual milk samples already at the end of the first day of grazing. Urine samples of all five cows showed higher concentrations of conjugated HGA and MCPrG metabolites than in milk. Observations suggest that dairy cows may have a low susceptibility toward sycamore maple toxins. However, whether this could be attributed to foregut fermenting species in general requires further elucidation.

Longitudinal Study for the Detection and Quantification of Campylobacter spp. in Dairy Cows during Milking and in the Dairy Farm Environment

Campylobacteriosis outbreaks have repeatedly been associated with the consumption of raw milk. This study aimed to explore the variation in the prevalence and concentration of Campylobacter spp. in cows' milk and feces, the farm environment and on the teat skin over an entire year at a small German dairy farm. Bi-weekly samples were collected from the environment (boot socks), teats, raw milk, milk filters, milking clusters and feces collected from the recta of dairy cows. Samples were analyzed for Campylobacter spp., E. coli, the total aerobic plate count and for Pseudomonas spp. The prevalence of Campylobacter spp. was found to be the highest in feces (77.1%), completely absent in milking equipment and low in raw milk (0.4%). The mean concentration of Campylobacter spp. was 2.43 log₁₀ colony-forming units (CFU)/g in feces and 1.26 log₁₀ CFU/teat swab. Only a single milk filter at the end of the milk pipeline and one individual cow's raw milk sample were positive on the same day, with a concentration of 2.74 log₁₀ CFU/filter and 2.37 log₁₀ CFU/mL for the raw milk. On the same day, nine teat swab samples tested positive for Campylobacter spp. This study highlights the persistence of Campylobacter spp. for at least one year in the intestine of individual cows and within the general farm environment and demonstrates that fecal cross-contamination of the teats can occur even when the contamination of raw milk is a rare event.

[Body temperature measurement in pigs: Are infrared thermometers a non-invasive alternative?]

OBJECTIVE

Internal body temperature is an essential parameter in evaluation an animal's general health status. The rectal temperature as 'gold standard' requires restraining of the animal which may cause stress especially when not accustomed to handling procedures. Stress on the other hand should whenever possible be avoided as it negatively affects animal welfare and may increase body temperature. The present study evaluated whether measuring the body surface temperature with an infrared thermometer (IRT) may represent a stressless alternative method to rectal body temperature measurements.

MATERIAL AND METHODS

Twelve male fattening pigs were included in the study. Body temperature was measured once a week for 11 weeks. Body surface temperature measurements were performed in the areas of the forehead, caudal base of the ear and anus using two infrared thermometers (IRT1 and IRT2) each.

RESULTS

Throughout the study, all pigs were clinically healthy. Best repeatability was found for the rectal thermometer and IRT1 in the anus region. Homogeneity of variance was not found for the measurements of the three thermometers. Mean values of body temperature were significantly different (p<0,05) between thermometers and measurement points. Thereby, the type of thermometer and measurement point possessed a moderate to strong effect. The Bland-Altman plot shows that differences in the values of the thermometers and measurement points are within the acceptable range of variation (95% interval). However, the range of variation is too substantial for clinical assessment of the body temperature.

CONCLUSION

The repeatability of temperature data measured with IRT on the body surface of pigs is acceptable. For this procedure, restraining the animals is not necessary, therefore reducing the animal's stress level during the clinical examination. However, the correlation to the rectal body temperature is weak to moderate.

CLINICAL RELEVANCE

In order to use IRT for health monitoring in animals, reference values for respective IRT and measurement points need to be established. In the current study no case of hyper- or hypothermia occurred. Further research is warrented to evaluate whether IRT reliably detect fever.

"Do not look at me like that": Is the facial expression score reliable and accurate to evaluate pain in large domestic animals? A systematic review

Introduction

Facial expression scoring has proven to be useful for pain evaluation in humans. In the last decade, equivalent scales have been developed for various animal species, including large domestic animals. The research question of this systematic review was as follows: is facial expression scoring (intervention) a valid method to evaluate pain (the outcome) in large domestic animals (population)?

Method

We searched two databases for relevant articles using the search string: "grimace scale" OR "facial expression" AND animal OR "farm animal" NOT "mouse" NOT "rat" NOT "laboratory animal." The risk of bias was estimated by adapting the Quality Assessment of Diagnostic Accuracy Studies (QUADAS) checklist.

Results

The search strategy extracted 30 articles, with the major share on equids and a considerable number on cows, pigs, and sheep. Most studies evaluated facial action units (FAUs), including the eye region, the orbital region, the cheek or the chewing muscles, the lips, the mouth, and the position of the ears. Interobserver reliability was tested in 21 studies. Overall FAU reliability was substantial, but there were differences for individual FAUs. The position of the ear had almost perfect interobserver reliability (interclass coefficient (ICC): 0.73-0.97). Validity was tested in five studies with the reported accuracy values ranging from 68.2 to 80.0%.

Discussion

This systematic review revealed that facial expression scores provide an easy method for learning and reliable test results to identify whether an animal is in pain or distress. Many studies lack a reference standard and a true control group. Further research is warranted to evaluate the test accuracy of facial expression scoring as a live pen side test.

Investigations on the Transfer of Quinolizidine Alkaloids from Lupinus angustifolius into the Milk of Dairy Cows

Lupin varieties with a low content of quinolizidine alkaloids (QAs) like blue sweet lupin (BSL) have long been used as a protein source for dairy cows. A health concern for humans may arise from the transfer of acute toxic QAs from feed into cow's milk. This study is the first to quantify the transfer of QAs from BSL into cow's milk with experimental and modeling methods. Four lactating dairy cows were subjected to two 7 day feeding periods with 1 and 2 kg/d BSL, respectively, each followed by a depuration period. BSL contained 1774 mg/kg dry matter total QAs. Individual milk samples were taken twice daily and QA contents in feed and milk determined with liquid chromatography-tandem mass spectrometry. Transfer of QAs into the milk was already seen with the administration of 1 kg/d BSL, with differences in transfer rates (TRs) between individual QAs. A toxicokinetic model was derived to quantify and predict QA feed-to-food transfer. For the four most prominent QAs, our model shows an α-half-life of around 0.27 d. TRs were obtained for six QAs and were between 0.13 (sparteine) and 3.74% (multiflorine). A toxicological assessment of milk containing QAs as measured in this study indicated a potential health concern.

Bored at home?—A systematic review on the effect of environmental enrichment on the welfare of laboratory rats and mice

Boredom is an emotional state that occurs when an individual has nothing to do, is not interested in the surrounding, and feels dreary and in a monotony. While this condition is usually defined for humans, it may very well describe the lives of many laboratory animals housed in small, barren cages. To make the cages less monotonous, environmental enrichment is often proposed. Although housing in a stimulating environment is still used predominantly as a luxury good and for treatment in preclinical research, enrichment is increasingly recognized to improve animal welfare. To gain insight into how stimulating environments influence the welfare of laboratory rodents, we conducted a systematic review of studies that analyzed the effect of enriched environment on behavioral parameters of animal well–being. Remarkably, a considerable number of these parameters can be associated with symptoms of boredom. Our findings show that a stimulating living environment is essential for the development of natural behavior and animal welfare of laboratory rats and mice alike, regardless of age and sex. Conversely, confinement and under-stimulation has potentially detrimental effects on the mental and physical health of laboratory rodents. We show that boredom in experimental animals is measurable and does not have to be accepted as inevitable.

Using an OSCE to Explore the Role of Structured Debriefing and Self-Directed Learning in Simulator-Based Clinical Skill Training in Production Animal Reproductive Medicine

Self-directed learning is associated with several benefits in simulation-based clinical skill training and can be complemented by feedback in the form of post-event debriefing. In this study, final-year veterinary medicine students (n = 111) were allocated into one of three groups and practiced four clinical skills from the domain of production animal reproductive medicine in a clinical skills laboratory. Group 1 completed an instructor-led practice session (I), group 2 completed a self-directed practice session with post-event debriefing (D), and group 3 completed a self-directed practice session without debriefing (control, C). Each practice session included two clinical skills categorized as being directly patient-related (patient) and two clinical skills involving laboratory diagnostics or assembling equipment (technical). Students evaluated the practice session using Likert-type scales. Two days after practice, 93 students took part in an objective structured clinical examination (OSCE). Student performance was analyzed for each learning station individually. The percentage of students who passed the OSCE did not differ significantly between the three groups at any learning station. While the examiner had an effect on absolute OSCE scores (%) at one learning station, the percentage of students who passed the OSCE did not differ between examiners. Patient learning stations were more popular with students than technical learning stations, and the percentage of students who passed the OSCE was significantly larger among students who enjoyed practicing at the respective station (90.9%) than among those who did not (77.8%).

Examining the Role of Structured Debriefing in Simulator-Based Clinical Skills Training for Namibian Veterinary Students: A Pilot Study

Post-event debriefing has been described as an effective tool in improving learning achievements in simulator-based teaching. This article examines the effect of structured post-event debriefing sessions in simulator-based veterinary clinical skills training. Nineteen Namibian veterinary students took part in instructor-led practice, self-directed practice with structured post-event debriefing and self-directed practice without debriefing (control) at three different learning stations in a veterinary clinical skills laboratory. Students evaluated their practice experience using Likert-type scales, and learning achievements were assessed using an objective structured clinical examination (OSCE). The results show that the choice of practice model had no significant effect on learning achievements overall. However, at individual learning stations, different practice models showed significant differences regarding effect on learning achievements. Students generally preferred practice sessions with some form of instructor involvement but the importance of instructor guidance was rated differently at each individual learning station.

Calving Management: A Questionnaire Survey of Veterinary Subject Matter Experts and Non-Experts

Simple Summary

We designed a questionnaire and asked two groups of veterinarians: (1) subject matter experts, who had published on calving management and (2) veterinary practitioners) for their opinion about aspects of calving management. Participants recommended to differentiate between the two stages of parturition and emphasized signs of imminent parturition, such as “restlessness” and “visibility of fetal parts”. There was no consensus on the right time to move the cow to the maternity pen. Almost half of the respondents recommended a 6-h observation interval for prepartum cows in the maternity pen. The two veterinary groups differed little in their knowledge of calving management.

Abstract

Accurate detection of the onset of parturition is a key factor in the prevention of dystocia. In order to establish current best practice recommendations for calving management, we asked subject matter experts (SME) who had published on calving management (by online survey, n = 80) and non-SMEs, veterinary practitioners (by workshop survey, n = 24) for their opinions. For this, we designed a questionnaire on the significance of signs of imminent parturition (SIP), the frequency of calving observation, and influencing factors for the timing of cow movement to a maternity pen. The response rate was 67.5% in the online survey and 100% in the workshop survey. The majority (89.7%) of all respondents agreed that it is beneficial for successful calving management to differentiate between stage I and II of parturition. Of 12 signs of imminent parturition (for stage I and II), “restlessness” and “visibility of fetal parts in vulva” were cited by 56.5% and 73.3% of SME and non-SME respondents, respectively. There was no consensus on the right time to move the cow to the maternity pen; recommendations varied from one to over 21 days. Almost half of the respondents (45.7%) recommended a 6-h observation interval for prepartum cows in the maternity pen. This study identified a strong consensus on the SIP and how and when to observe cows prior to parturition. SMEs and non-SMEs provided broadly similar recommendations, while the SMEs and the non-SMEs differed significantly in the number of publications on calving they authored, they differed little in their knowledge of calving management.

Sensitivity and specificity of a tail-activity measuring device for calving prediction in dairy cattle

Efficient calving surveillance is essential for avoiding stillbirth due to unattended dystocia. Calving sensors can help detect the onset of parturition and thus ensure timely calving assistance if necessary. Tail-raising is an indicator of imminent calving. The objective of this study was to evaluate a tail-mounted inclinometer sensor (Moocall Ltd., Dublin, Ireland) and to monitor skin integrity after sensor attachment. Cows (n = 157) and heifers (n = 23) were enrolled at 275 d post insemination, and a sensor was attached to each cow's tail. Investigators checked for signs indicating the onset of stage II of parturition, verified the position of the sensor, and evaluated the skin integrity of the tail above and below the sensor hourly for 24 h/d. We used 5 different intervals (i.e., 1, 2, 4, 12, and 24 h until calving) to calculate sensitivity and specificity. Sensors continuously remained on the tail (i.e., within 3 cm of the initial attachment position) after initial attachment until the onset of calving in only 13.9% of animals (n = 25). Sensors were reattached until a calving event occurred (51.6%) or the animal was excluded for other reasons (34.4%). In 31 animals the sensor was removed because the tail was swollen or painful. Heifers were significantly less likely than cows to lose a sensor but more likely to experience tail swelling or pain. Depending on the interval preceding the onset of parturition, sensitivity varied from 19 to 75% and specificity from 63 to 96%.

[Taking body temperature in cattle - critical evaluation of an established diagnostic test]

Measuring the body temperature is an essential component of the clinical examination of bovines. Next to its value for the diagnosis of diseases, body temperature also is an important value in clinical studies concerning estrus detection, calving time point prediction, or the evaluation of heat stress. This systematic review critically evaluates different methods of measuring bovine body temperature including rectal measurement, vaginal or ruminal temperature loggers, milk temperature, and infrared body surface thermography. Although body temperature measurement is a commonly employed and established diagnostic test, a close look at scientific studies displays multiple factors influencing body temperature data. The variability of results emphasizes the relevance of critically evaluating new measuring methods before introducing them into research or routine practice. Especially in terms of identifying specific cut-off values, i. e. for fever defined as body temperature > 39.5°C, the precision of the method is of importance, as the acquired values possess a high degree of influence on the veterinary decision taking process.

Influence of denaverine hydrochloride on calving ease in Holstein-Friesian heifers

Calving is assumed to be an exhausting and painful event. A drug that eases the calving procedure and alleviates pain would help cows, especially those suffering from dystocia. In a randomized, controlled, and blinded trial, we measured the effect of denaverine hydrochloride on physical and physiological calving parameters. Eighty-three Holstein-Friesian heifers were included in the analysis. Pulling force was measured using a digital force gauge interposed between the calf and a mechanical calf puller. The concentration of cortisol was measured in serum before and after parturition. There was no effect of treatment group on calving modality (i.e., spontaneous vs. assisted calving), duration of calving, and cortisol concentration. The area under the curve of pulling force × time (n = 44), however, was significantly smaller in the treatment group compared with the placebo group. Also, duration of calving assistance was numerically shorter in the treatment group compared with the placebo group. The results provide evidence that calving ease can be influenced by denaverine hydrochloride during calving assistance.

Effect of denaverine hydrochloride application to heifers on the APGAR score and lactate concentration in newborn calves

OBJECTIVE

The aim of this study was to evaluate the influence of Denaverine hydrochloride (DNH) in heifers on calf vitality.

MATERIAL AND METHODS

A total of 83 calvings with 38 female and 45 male calves were included in the study. Thirty minutes after onset of stage 2 of calving, 400 mg DNH or placebo (0.9% NaCl) were administered subcutaneously. If the calving procedure was not completed after 60 minutes, an extraction was conducted and pulling force was measured by using a digital force gauge. Directly after parturition, vitality of calves was evaluated using a modified APGAR score. Additionally, lactate concentration in blood from Vena auricularis was measured with a handheld measuring device (lactate scout).

RESULTS

No effect of treatment was observed on APGAR score and lactate concentration.

CLINICAL RELEVANCE

Denaverine hydrochloride is a regularly used substance in obstetrics in veterinary medicine in many European countries. We could not confirm our hypotheses that treating heifers with DNH has a positive effect on calf vitality evaluated by APGAR score and lactate concentration in blood.

A Proof of Concept: Are Detection Dogs a Useful Tool to Verify Potential Biomarkers for Lung Cancer?

Early and reliable diagnostic test is essential for effective therapy of lung cancer. Volatile organic compounds that are characteristic for cancer could serve as valuable biomarkers in cancer diagnosis. Both trace analytical and detection dog approaches give some evidence for the existence of such biomarkers. In this proof of concept, study dogs and trace analysis were implemented in combination to gain more information concerning cancer biomarkers. Two dogs were trained to distinguish between absorbed breath samples of lung cancer patients and healthy persons and succeeded with correct identification of patients with 9/9 and 8/9 and correct negative indications from of 8/10 and 4/10 samples from healthy individuals. A recent observational study found that breath samples from lung cancer patients showed an increase in 1-butanol, 2-butanone, 2-pentanone, and hexanal. Synthetic air samples were therefore fortified with these compounds and adsorbed to a fleece. Tested against breath samples from healthy probands, on presentation to the dogs these synthetic samples provoked an indication in three out of four samples. We were able to demonstrate that a combination of the natural nose of a dog and a trace analytic technique can be a valuable concept in the search for cancer biomarkers.

Short communication: Is hair cortisol a potential indicator for stress caused by chronic lameness in dairy cows?

The objective of this study was to evaluate hair cortisol concentration as an indicator for stress caused by chronic lameness in dairy cows. Sixty-eight cows were scored for lameness for 4 consecutive weeks. The hair of the tail switch was clipped at the beginning of the study and regrown hair was clipped after 4 wk. Hair samples were analyzed for cortisol concentration. Animals with 2 consecutive locomotion scores ≥3 or with an overall mean score >1.5 were classified as lame. After pair matching lame and nonlame cows, considering days in milk, lactation number, and milk yield, and excluding cows with less than 20 mg hair sample for analysis, 21 lame and 21 nonlame cows were included in the analysis. The mean hair cortisol concentration in this study was 2.32 ± 0.35 pg/mg (mean ± standard deviation). Cortisol concentration from hair regrown in the study period was 2.38 ± 0.95 and 2.26 ± 1.35 pg/mg for lame and nonlame cows (n = 21), respectively; we found no difference in mean cortisol level of primiparous and multiparous cows. Based on these data, hair cortisol concentration was not a useful indicator to differentiate cows with chronic lameness and healthy cows.

Odor Perception by Dogs: Evaluating Two Training Approaches for Odor Learning of Sniffer Dogs

In this study, a standardized experimental set-up with various combinations of herbs as odor sources was designed. Two training approaches for sniffer dogs were compared; first, training with a pure reference odor, and second, training with a variety of odor mixtures with the target odor as a common denominator. The ability of the dogs to identify the target odor in a new context was tested. Six different herbs (basil, St. John's wort, dandelion, marjoram, parsley, ribwort) were chosen to produce reference materials in various mixtures with (positive) and without (negative) chamomile as the target odor source. The dogs were trained to show 1 of 2 different behaviors, 1 for the positive, and 1 for the negative sample as a yes/no task. Tests were double blind with one sample presented at a time. In both training approaches, dogs were able to detect chamomile as the target odor in any presented mixture with an average sensitivity of 72% and a specificity of 84%. Dogs trained with odor mixture containing the target odor had more correct indications in the transfer task.

A survey of drying-off practices on commercial dairy farms in northern Germany and a comparison to science-based recommendations

While dry cow management is important for health, milk production and fertility information on drying-off procedures implemented on commercial dairy farms is lacking. Current drying-off management procedures on commercial dairy farms were evaluated using a questionnaire and results compared with recommendations given in the current literature. Ninety-one participants from a farmer education event completed the survey. On average, cows were dried off seven weeks before calving. Only 9.9 per cent of the farms had a dry period length of five weeks or less. A continuous milking regime without dry period was not established on any farm participating in the survey. Most farmers performed an abrupt drying-off (73.0 per cent). Only 11.8 and 15.0 per cent attempted to lower milk yield prior to drying-off by reducing milking frequencies and adjusting feed rations, respectively. While a blanket antibiotic dry cow treatment was carried out on 79.6 per cent of the farms, selective dry cow treatment was not mentioned by any farmer. Although 77.4 per cent preponed the drying-off date in low-yielding cows, an altered drying-off procedure in high-yielding dairy cows was rare (9.7 per cent). This survey provides an insight into drying-off procedures currently applied on commercial dairy farms in northern Germany.

In vitro cultured lung cancer cells are not suitable for animal-based breath biomarker detection

In vitro cultured lung cancer cell lines were investigated regarding the possible identification of volatile organic compounds as potential biomarkers. Gas samples from the headspace of pure culture medium and from the cultures of human lung adenocarcinoma cell lines A549 and Lu7466 were exposed to polypropylene fleece in order to absorb odour components. Sniffer dogs were trained with loaded fleeces of both cell lines, and honey bees were trained with fleeces exposed to A549. Afterwards, their ability to distinguish between cell-free culture medium odour and lung cancer cell odour was tested. Neither bees nor dogs were able to discriminate between odours from the cancer cell cultures and the pure culture medium. Solid phase micro extraction followed by gas chromatography with mass selective detection produced profiles of volatiles from the headspace offered to the animals. The profiles from the cell lines were largely similar; distinct differences were based on the decrease of volatile culture medium components due to the cells' metabolic activity. In summary, cultured lung cancer cell lines do not produce any biomarkers recognizable by animals or gas chromatographic analysis.

Validation of bovine oestrous-specific synthetic molecules with trained scent dogs; similarities between natural and synthetic oestrous smell

Oestrous detection is crucial for successful dairy cow reproduction. Bulls identify cows in oestrus by oestrous-specific odours especially in urine and vaginal fluid. These have been used to train dogs to detect cows in heat. To improve and simplify the dog training, a spray containing synthetic oestrous molecules was developed. The objective of this study was to test the spray on similarities to the natural substance thus to assess its suitability as a training substance for heat detection dogs. Ten privately owned dogs of various breeds were trained. Dogs should be trained either to differentiate natural vaginal fluid from cows in oestrus and dioestrus (n = 5), or spray with or without synthetic oestrous molecules (n = 5). Dogs trained on natural fluid and on spray could detect the oestrous odour they had been trained on with an overall accuracy of 69.0% and 82.4%, respectively (p = 0.019). To validate the synthetic molecules, dogs trained with synthetic molecules had to detect oestrous odour in natural fluid without further training (accuracy 37.6%). Dogs trained on natural fluid detected the synthetic molecules with an accuracy of 50.0% (50% vs 37.4%, p < 0.05). Dogs can recognize natural vaginal fluid from cows in oestrus after they have been trained with synthetic oestrous molecules, but accuracy needs to be improved.

Behavioural and physiological assessment of stress reactions during vaginal examination in dairy cows

Objectives and aim: The objective of this study was to determine the origin of an arched back in cows during vaginal examination. Moreover, we tested whether the duration of an arched back and avoidance reactions during vaginal examination can be decreased by epidural anaesthesia or analgesic treatment. Material and methods: Behaviour during cleaning of the perivaginal region and during vaginal examination was scored using the avoidance reactivity score (ARS). Heart rate (HR) was recorded in 10 dairy cows considering four experimental phases, i.e. baseline, cleaning the perivaginal region, vaginal examination and post-examination. Each cow was examined three times and received no treatment (CON), an epidural anaesthesia (EPID) or an analgesic treatment (NSAID). The duration of an arched back during and post-examination was measured. Results: The expression of the arched back was shortest in cows of group EPID and longest in cows of group CON. Avoidance reactions did not differ between the cleaning phase and vaginal examination in cows of group EPID. Cows of group CON showed the strongest avoidance reactions during examination, whereas cows of group EPID showed least avoidance reactions. Mean HR increased during cleaning and vaginal examination and decreased post-examination. Mean HR during vaginal examination did not differ between treatment groups. Conclusion: The results show that cows express discomfort during vaginal examination with an increase in avoidance reactions and HR. Although epidural anaesthesia could reduce sensitivity in the perivaginal region, cows still felt the urge to empty the vagina from the examiner’s hand and, thus, were arching their back. Clinical relevance: In practice, routine vaginal examinations in dairy cows have not been considered as invasive examinations. Our results show that vaginal examinations indeed do cause discomfort. We do not suggest the application of any anaesthetic treatment as appropriate before routine vaginal examinations. None theless, the examiner should be aware of the stress potential of vaginal examinations and conduct such examinations most carefully.

Behavioural and physiological assessment of stress reactions during vaginal examination in dairy cows

OBJECTIVES AND AIM

The objective of this study was to determine the origin of an arched back in cows during vaginal examination. Moreover, we tested whether the duration of an arched back and avoidance reactions during vaginal examination can be decreased by epidural anaesthesia or analgesic treatment.

MATERIAL AND METHODS

Behaviour during cleaning of the perivaginal region and during vaginal examination was scored using the avoidance reactivity score (ARS). Heart rate (HR) was recorded in 10 dairy cows considering four experimental phases, i.e. baseline, cleaning the perivaginal region, vaginal examination and post-examination. Each cow was examined three times and received no treatment (CON), an epidural anaesthesia (EPID) or an analgesic treatment (NSAID). The duration of an arched back during and post-examination was measured.

RESULTS

The expression of the arched back was shortest in cows of group EPID and longest in cows of group CON. Avoidance reactions did not differ between the cleaning phase and vaginal examination in cows of group EPID. Cows of group CON showed the strongest avoidance reactions during examination, whereas cows of group EPID showed least avoidance reactions. Mean HR increased during cleaning and vaginal examination and decreased post-examination. Mean HR during vaginal examination did not differ between treatment groups.

CONCLUSION

The results show that cows express discomfort during vaginal examination with an increase in avoidance reactions and HR. Although epidural anaesthesia could reduce sensitivity in the perivaginal region, cows still felt the urge to empty the vagina from the examiner's hand and, thus, were arching their back.

CLINICAL RELEVANCE

In practice, routine vaginal examinations in dairy cows have not been considered as invasive examina- tions. Our results show that vaginal examinations indeed do cause discomfort. We do not suggest the application of any anaesthetic treatment as appropriate before routine vaginal examinations. Nonetheless, the examiner should be aware of the stress potential of vaginal examinations and conduct such examinations most carefully.

Measurement of fecal glucocorticoid metabolites and evaluation of udder characteristics to estimate stress after sudden dry-off in dairy cows with different milk yields

Sudden dry-off is an established management practice in the dairy industry. But milk yield has been increasing continuously during the last decades. There is no information whether the dry-off procedure, which often results in swollen and firm udders, causes stress, particularly in high-producing dairy cows. Therefore, we evaluated the effect of a sudden dry-off on extramammary udder pressure and the concentration of fecal glucocorticoid metabolites (i.e., 11,17-dioxoandrostane, 11,17-DOA) as an indirect stress parameter. Measurements were carried out within the last week before dry-off and until 9d after dry-off considering 3 groups of milk yield (i.e., low: <15 kg/d, medium: 15-20 kg/d, and high: >20 kg/d). Udder pressure increased in all yield groups after dry-off, peaked at d 2 after dry-off and decreased afterwards. Pressures were highest in high-yielding cows and lowest in low-yielding cows. But only in high-yielding cows was udder pressure after dry-off higher than before dry-off. Baseline 11,17-DOA concentrations depended on milk yield. They were highest in low-yielding (121.7 ± 33.3 ng/g) and lowest in high-yielding cows (71.1 ± 30.0 ng/g). After dry-off, 11,17-DOA increased in all yield groups and peaked at d 3. Whereas in medium- and high-yielding cows 11,17-DOA levels differed significantly from their respective baseline during the whole 9-d measuring period, low-yielding cows showed elevated 11,17-DOA levels only on d 3 after dry-off. However, especially the increase in 11,17-DOA after dry-off between the 3 yield groups was considerably different. Mean 11,17-DOA increase from baseline to d 3 was highest in high-yielding cows (129.1%) and considerably lower in low-yielding cows (40.1%). The highest fecal 11,17-DOA concentrations were measured on d 3 after dry-off, indicating that the stress was most intense on d 2, which is due to an 18-h time lag; at about the same time, udder pressure peaked. Our results showed a negligible effect of a sudden dry-off on low-yielding cows. High-yielding cows, however, faced high extramammary pressures and increased glucocorticoid production. Considering animal welfare aspects, a review of the current dry-off strategies might be warranted.

Short communication: Evaluation of vaginal discharge following treatment with a progesterone insert

Yellowish discharge after application of intravaginal progesterone releasing inserts is frequently observed in cows. The objective of this study was to compare the bacteriological contamination of the vagina and uterus before and after a treatment with a progesterone insert in heifers. Forty-two Holstein heifers received a progesterone releasing insert [Eazi-Breed controlled internal drug release (CIDR) insert; Pfizer Animal Health, Berlin, Germany] for 7d. The protruding tail had been removed from half of the inserts (no tail group: n=21; tail group: n=21). Nine heifers from the tail group lost the insert within the 7-d treatment interval and were excluded. Heifers identified in estrus were artificially inseminated on d 9 or 10. Vaginal discharge was scored on a 4-point scale [vaginal discharge score (VDS) 0 to 3] and vaginal swabs were taken for bacteriological examination on d 0 and 7 and the day of artificial insemination (AI). Furthermore, cytological and bacteriological samples were obtained from the uterus on d 7 and the day of AI. On d 0, coliforms and Streptococcus spp. were found in vaginal swabs of 21 heifers (64%). On d 7, all heifers showed purulent vaginal discharge (VDS 2 to 3). The VDS was higher in the tail group compared with the no tail group. Arcanobacterium pyogenes, coliforms, and Streptococcus spp. were isolated from the vaginal swabs in 32 of 33 (96%) heifers on d 7. On the day of AI, VDS had improved to 0 or 1 in 96% of the heifers. However, A. pyogenes, coliforms, and Streptococcus spp. were still isolated in 17 of 33 (53%) heifers from the vagina and in 32 of 33 (96%) heifers from the endometrium. Endometrial cytology revealed polymorphonuclear neutrophils (PMN) in 11 heifers (6 to 32% PMN). Five samples exceeded the threshold of 5% PMN, and 2 samples exceeded the 10% PMN threshold, indicative of subclinical endometritis. In conclusion, pyogenic bacteria were found in the vagina and uterus on d 7 and the day of AI after intravaginal progesterone treatment. The severity of the discharge was affected by the protruding tail of the insert.

[Efficacy of vaginal progesterone inserts (CIDR) to reduce early embryonic losses in dairy cows]

The OBJECTIVE of this study was to test the efficacy of a progesterone releasing device (CIDR®, Pfizer, Germany) inserted on day (d) 20 post insemination (p.i.) to reduce embryonic losses between d 27 and 39 p.i. Furthermore, we hypothesized that CIDR® increases blood progesterone levels during the application period, but does not affect the maintenance of pregnancy after removal.

MATERIAL AND METHODS

The study was conducted on a commercial dairy farm, randomly allocating 74 Holstein Friesian cows to one of two groups. These cows were non-pregnant after previous artificial insemination and treated with an Ovsynch protocol. Group 1 (n=36) received a CIDR® on d 20 p.i. (CIDR® group) while group 2 (n=38) remained untreated (control group). CIDR® was removed on d 39 p.i. Blood samples were drawn from all cows on d 20, 27, 39 and 55 p.i. for analysis of progesterone (P4) concentrations by immunoassay (ADVIA Centaur®, Siemens, Germany). Pregnancy diagnosis was conducted on d 27 p.i. with ultrasonography, and on d 39 and 55 p.i. by transrectal palpation.

RESULTS

The overall prevalence rate of early embryonic losses between d 27 and 39 p.i. was 37.1% (CIDR® group 35.3%, control group 38.9%; p=0.83). On d 39 p.i. 30.5% of all cows were pregnant and the percentage of pregnant cows did not differ between the study groups (p=0.83). Progesterone levels on d 20 p.i. did not differ among cows which were pregnant on d 39 p.i. (p=0.57). On d 27 p.i. progesterone levels in pregnant cows were higher in the CIDR® group (16.2 ± 9.9 ng/ml) compared to the control group (11.2 ± 3.4 ng/ml; p=0.04). Progesterone concentrations were lower on d 39 p.i., but still differed between study groups (p=0.05). After removal of CIDR®, blood progesterone levels did not differ between pregnant cows of both study groups on d 55 p.i. (p=0.36).

CONCLUSION

The application of a progesterone releasing device led to increased blood progesterone levels during the application period, but did not affect maintenance of pregnancy after its removal.

CLINICAL RELEVANCE

Supplementation with progesterone at d 20 p.i. does not decrease early embryonic losses between d 27 and 39 p.i. or increase the number of cows pregnant on d 39 p.i.

Wirksamkeit einer vaginalen Progesteronspange zur Verringerung embryonaler Verluste in der Frühträchtigkeit bei Milchkühen

Ziel der Studie war, den Einfluss einer intravaginalen Progesteronspange (CIDR®, Pfizer) auf embryonale Verluste zwischen Tag 27 und 39 post inseminationem (p. i.) zu testen. Geprüft wurden ferner die Hypothesen, dass die Progesteronspange die Serum-Progesteronkonzentration während der Anwendung beeinflusst und sich nach ihrer Entfernung keine negativen Auswirkungen auf das Fortbestehen der Trächtigkeit ergeben. Material und Methoden: Bei 74 Kühen eines Milchviehbetriebs in Brandenburg erfolgte eine zufällige Zuordnung zu zwei Gruppen. Diese Tiere waren nach Besamung als nichttragend diagnostiziert worden und wurden daraufhin hormonell in einem Ovsynch-Programm behandelt und terminiert besamt. Kühe der CIDR®-Gruppe (n = 36) erhielten an Tag 20 p. i. eine Progesteronspange, die an Tag 39 p. i. entfernt wurde. Kühe der Kontrollgruppe (n = 38) blieben unbehandelt. Blutproben zur Messung der Progesteronkonzentration mittels Immunoassay wurden an den Tagen 20, 27, 39 und 55 p. i. entnommen. Trächtigkeitsuntersuchungen fanden an Tag 27 p. i. mittels Ultraschall und an den Tagen 39 und 55 p. i. mittels rektaler Palpation statt. Ergebnisse: Die embryonalen Verluste zwischen Tag 27 und 39 p. i. betrugen insgesamt 37,1% (CIDR®-Gruppe: 35,3%; Kontrollgruppe: 38,9%; p = 0,83). Die Progesteronkonzentrationen unterschieden sich an Tag 20 p. i. zwischen den an Tag 39 p. i. trächtigen Tieren beider Gruppen nicht. An Tag 27 p. i. lag die Konzentration in der CIDR®-Gruppe mit 16,2 ± 9,9 ng/ ml höher als in der Kontrollgruppe mit 11,2 ± 3,4 ng/ml (p = 0,04). Nach Präparatentfernung zeigten Kühe der CIDR®-Gruppe an Tag 55 p. i. keine höheren Progesteronwerte als Kontrolltiere. Schlussfolgerung: Die Progesteronspange steigerte die Progesteron konzentration während der Anwendung und ihre Entfernung hatte keinen negativen Einfluss auf das Fortbestehen der Trächtigkeit . Klinische Relevanz: Die Supplementierung mit Progesteron an Tag 20 p. i. kann die embryonalen Verluste zwischen Tag 27 und 39 p. i. nicht verringern oder den Anteil tragender Tiere erhöhen.

[Inappropriate lactation syndrome in goats--case collection and experiences with mastectomy]

OBJECTIVE

Hobby keeping of goats and sheep confronts veterinarians with new challenges that rarely have to be faced in livestock husbandry. During the last five years five goats were presented to the Clinic for Animal Reproduction, Faculty of Veterinary Medicine, Freie Universität Berlin, Germany, with inappropriate lactation syndrome. Four of these animals had been previously treated with cabergoline without enduring success. According to the request of the owners (informed consent) and the clinical severity of the cases, a mastectomy was performed in all five animals.

MATERIAL AND METHODS

Surgery was performed under general anaesthesia using ketamine and xylazine, and with the patients in a recumbent position.

RESULTS

Mastectomy in small ruminants requires knowledge of the anatomy of the udder and the possible positions of the supplying blood vessels. Our patients displayed a variety of dispositions of the Vena epigastrica caudalis superficialis. Special attention should be paid to a careful and blunt dissection of the mammary gland, and immediate control of haemorrhage, to maintain a clear view on the anatomic structures. Furthermore, dissection of the glandular tissue should be strictly avoided to prevent milk contamination of the surgical area. A sufficient skin flap has to be left to cover the surgical area after removal of the udder.

CONCLUSION AND CLINICAL RELEVANCE

Even though udder amputation appears to be a radical and high-risk procedure, all five goats survived the surgery. The wound healing occurred in a reasonable time without any severe complications. In goats that are kept as "hobby animals" and in which an inappropriate lactation syndrome cannot be treated conservatively, mastectomy is a reasonable and promising therapy.

Lactatio falsa bei der Ziege – Fallsammlung und Erfahrungen mit der Amputation des Gesäuges

Gegenstand: Die Haltung von Schafen und Ziegen als Hobbytiere konfrontiert Tierärzte mitunter mit Problemen, die bei einer reinen Nutztierhaltung eher selten vorkommen. In den letzten 5 Jahren wurden der Tierklinik für Fortpflanzung der FU Berlin fünf Ziegen aus Hobbyhaltungen mit rezidivierender Lactatio falsa vorgestellt. Vier Tiere waren in der Vergangenheit bereits mit Cabergolin mit ausbleibendem oder nur kurzfristigem Erfolg behandelt worden. Aufgrund der Größe des Euters wurde auf Wunsch der Besitzer bei allen fünf Ziegen eine Euteramputation vorgenommen. Material und Methoden: Der operative Eingriff erfolgte unter Allgemeinanästhesie mit Ketamin und Xylazin in Rückenlage der Patienten. Ergebnisse: Die durchgeführte Anästhesie erwies sich für den Eingriff als geeignet. Die Mastektomie bei Ziegen erfordert spezielle Kenntnisse hinsichtlich der Anatomie der Milchdrüse und ihrer versorgenden Gefäße. Bei den fünf Patienten war eine teils unterschiedliche Anlage der Vena epigastrica caudalis superficialis festzustellen. Bei der Operation zu beachten sind insbesondere das vorsichtige und stumpfe Präparieren und eine schnelle Blutstillung, um ein übersicht - liches Operationsfeld zu erhalten. Die Eröffnung von Zisternen oder Drüsengewebe sollte vermieden werden, damit keine Milch austritt, da daraus Wundheilungsstörungen entstehen könnten. Ein ausreichender Hautlappen für den späteren Wundverschluss muss belassen werden. Schlussfolgerung und klinische Relevanz: Alle fünf Ziegen überstanden die Operation ohne Komplikationen. Die Wunden heilten schnell und nahezu ohne Probleme. Für als Hobbytiere gehaltene Ziegen mit Lactatio falsa, die konservativ nicht therapiert werden können, stellt die Mastektomie eine sinnvolle, erfolgversprechende Behand - lung dar.

Efficacy of a treatment with hCG 4 days after AI to reduce pregnancy losses in lactating dairy cows after synchronized ovulation

Content The objective of the study was to investigate whether a treatment with hCG 4 days after AI could reduce pregnancy losses in lactating dairy cows. Cows of a dairy herd presented to the veterinarian in a fixed reproductive management protocol were treated with an Ovsynch protocol if no corpus luteum (CL) could be palpated per rectum (Group OV). Cows with a CL received cloprostenol (0.15 mg). After 2 days, these cows were treated with buserelin (0.01 mg) and received timed AI 16-20 h later (Group PG). In both treatment protocols, cows were assigned to two groups to receive 2500 IU of hCG i.v. 4 days after AI or to serve as untreated controls (Groups OV-hCG, OV-Control, PG-hCG and PG-Control). Pregnancy diagnosis was carried out 27 days after AI via ultrasonography and 39 days after AI by rectal palpation. Pregnancy losses were defined as cows being pregnant on day 27 but not pregnant on day 39 after AI. Pregnancy rate (PR) by day 27 did not differ among the four groups (35.4, 35.0, 37.0 and 38.0% for Groups OV-hCG, OV-Control, PG-hCG and PG-Control, respectively). Pregnancy losses between day 27 and day 39 after AI were smaller in hCG treated animals in summer but not in autumn and spring. Pregnancy rate by day 39 after AI was higher in PG than in OV groups, but independent of hCG-treatment. In conclusion, treatment with hCG 4 days after AI did not significantly increase PR on 39 days after AI. A positive effect of hCG on pregnancy losses during the summer months warrants further investigation.

Serosurvey for selected infectious disease agents in free-ranging black and white rhinoceros in Africa

Two hundred and eighty one serum samples collected from free-ranging black (Diceros bicornis) and white (Ceratotherium simum) rhinoceros, in the Republic of South Africa (RSA), Namibia, and Kenya from 1987-97, were examined for antibody to 16 different infectious agents. Positive antibody titers were detected against Akabane (59.8%), bluetongue (55%), African horse sickness (27.9%), epizootic haemorrhagic disease of deer (19.4%), parainfluenza type 3 (25.3%), bovine herpes virus 1 (3.1%), equine herpes virus 1 (8.8%) and bovine viral diarrhea (1.2%) viruses, and four serovars of Leptospira interrogans, (ranging 1.2 to 8.8%). No antibody was detected against Rift Valley fever virus, encephalomyocarditis virus, Brucella abortus, and Trypanosoma equiperdum. Interspecies differences were detected for African horse sickness, epizootic haemorrhagic disease of deer and parainfluenza type 3 viruses. There appeared to be some geographic variation in the prevalence of antibody for African horse sickness, bluetongue, epizootic haemorrhagic disease of deer, parainfluenza type 3, equine herpes virus 1 and Leptospira interrogans serovar bratislava.