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Current lifestyles are leading to a worldwide increase in metabolic liver diseases that favor the development of liver disease. Changes in hepatocytes are caused by altered lipid concentrations, oxidative stress or toxicity by individual lipids. The complexity of the underlying processes and differences of the pathology to proposed rodent models makes the development of an effective targeted therapy difficult. The lipid mobilization that occurs in dairy cows in the postpartum period could be a natural model for the metabolic stress commonly observed in the development of liver diseases. We therefore used gas chromatography and histopathological staining techniques to analyze lipid patterns in diparous and multiparous cows during the peripartum period. The most striking change in lipid composition is the homogenous increase in palmitoleic acid (C16:1n7) content in all cows around the time of calving, with multiparous cows exhibiting consistently higher C16:1n7 levels by the end of the study. Elevated C16:1n7 levels have a potential key role in the development of non-alcoholic steatohepatitis (NASH) and tumorigenesis in the liver. Changes in C16:1n7, therefore, support the idea that lipid mobilization in dairy cows could serve as model for various liver diseases, such as nonalcoholic fatty liver disease (NAFLD) or NASH development.

A fourth lactation dairy cow that was 35 days in milk was referred to the clinic for treatment after undergoing unsuccessful treatment of a left displaced abomasum (LDA). The physical examination revealed complications after using the “blind-stitch” method for correction of the LDA; the cow had an abnormal general demeanor, decreased gastrointestinal motility, and local inflammation of the abdominal wall at the site of the suture. Systemic antibiotics, anti-inflammatory drugs, and intravenous fluids were administered, and a right flank laparotomy and omentopexy according to Dirksen were performed after cutting the suture and breaking down the adhesions of the localized peritonitis between the abdominal wall and the abomasal puncture site. The cow was monitored clinically and discharged 2 weeks after referral. The cow was milked for another two lactations producing a total of 18,000 kg of milk, with a lifetime production of 59,141 kg. The total cost for the case was 310 € for the first intervention using the “blind-stitch” method and 897 € for the second laparotomic intervention. The costs (excluding tax) of both procedures including physical examination, surgery, medications, diagnostics, and labor were calculated. The lost revenue associated with the withdrawal period and lower milk production was 4,168 €. Percutaneous LDA fixation techniques, such as the “blind-stitch” and “toggle-pin” methods, have gained popularity because they are quick and cost-effective and involve minimal labor. However, many buiatricians are critical of these techniques because of the high risk of complications. The following four factors require careful consideration when choosing a method for LDA correction: (1) Percutaneous methods require precision and adherence to the described inclusion, exclusion, and cancelation criteria; (2) Operator skill is essential, and therefore regularly performing laparotomies increases surgical experience and enables the veterinarian to better manage different and more complex abdominal disorders; (3) By performing a laparotomy, other underlying abdominal disorders such as reticuloperitonitis and abomasal ulcers may be detected; (4) Postoperative husbandry and treatment are important factors affecting the outcome. The cost calculated for this case underlines the potential benefit and necessity of successful animal health management and the importance of a highly skilled veterinarian and farm workforce.

ABSTRACT: Animal experimentation is required to investigate complex physiological relationships and facilitates development of evidence-based knowledge. However, experimental protocols can interfere with the daily routine of the animals, result in stress and pain, and have adverse effects on health and production. The goal of this study was to investigate the effects of an intensive experimental protocol on health traits and production in transition dairy cows. Eighty experimental dairy Holstein cows (EXP group) underwent serial protocol-based clinical and ultrasonographic examinations, puncture of the jugular vein for blood collection or drug application, and liver biopsy samples, 14 d before until 42 d after parturition. Controls (CTR group) included 206 cows from the same herd, which fulfilled the same inclusion criteria and were kept under the same production management but were not handled for the purpose of this study. Procedure-related effects with a potentially negative effect on health and production were recorded. Furthermore, production, fertility and culling traits of the 2 groups (CTR, EXP) were compared. Most procedure-related adverse effects were associated with transcutaneous liver biopsies and included diffuse inflammation of the skin incision in 11.9% (42 of 320), abscessation of the skin or subcutis in 4.6% (11 of 240), and increased liver echogenicity of the biopsy site in 10.4% (27 of 240). The experimental procedures had a negative effect on milk yield at the start [days in milk (DIM) 5–50, difference: 2.3 kg, standard error (SE): 0.8 kg] and end of lactation (DIM 251–300, difference: 2.0 kg, SE: 1.0 kg; DIM 301–350, difference: 2.3 kg, SE: 1.2 kg) resulting in a lower 305-d milk yield in the EXP group than in the CTR group (difference: 472 kg, SE 214 kg). The milk fat % was higher in the EXP group than in the CTR group from 251 DIM onward (DIM 251–300, difference: 0.20%, SE: 0.09%; DIM 301–350, difference: 0.41%, SE: 0.17%). Also, the somatic cell score was higher in the EXP group than in the CTR group, during early (5–50 DIM, difference: 0.43, SE: 0.22) and from mid-lactation onward (DIM 151–200, difference: 0.43, SE: 0.2; DIM 201–250, difference: 0.49, SE: 0.22; DIM 251–300, difference: 0.55, SE: 0.25; DIM 301–350, difference: 0.61, SE: 0.28). Experimental procedures had no effect on first service conception rate and time to pregnancy, but had a positive effect on stillbirth rate with fewer stillbirths in the CTR group (0%) than in the EXP group (3.9%). Furthermore, experimental handling had no effect on time to culling or type of culling, whereby poor production was a more frequent reason noted for culling in the EXP group. Procedure-associated impairment of production in dairy cows is rarely reported and allows the estimation of the effects of such a study protocol on animal health and production. As a limitation for the interpretation of the results, the number of animals included and conduction in one single herd have to be considered.

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

Surveillance of antimicrobial administration in livestock production is an important factor in global policies to reduce spreading of antimicrobial resistance. In recent years, many studies have been carried out concerning the usage of antimicrobials in animal production and in some countries recording of antimicrobial quantities dispensed to famers is mandatory. On cattle farms, antimicrobial treatments are recorded for fattening calves under 8 months of age and for fattening cattle older than 8 months in Germany and treatment frequencies are then calculated. However, with the entry into force of Regulation (EU) 2019/6 on 01/28/2022, antimicrobial monitoring will gradually be extended to all animal species and age groups. Therefore, an effective, fast and accurate transfer of data on the use of antimicrobials, especially in the field of livestock farming, into corresponding databases is required to determine the treatment frequencies for the individual animal species or types of use. For this purpose, an electronic interface was programmed to transfer the data on antimicrobial use in dairy cattle farms from a herd management software program directly into a database. To test the practicability and effectiveness of this interface, 10 dairy cattle farms from Saxony were initially selected. Based on an in-depth analysis of the treatment frequencies of antimicrobial administration of 7 different age groups of animals after a two-year observation period, the functionality of the electronic interface could be established. The greatest potential for reduction of antimicrobials is in newborn calves, as they represent the age group with the highest treatment frequency.

We studied the prevalence of extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae in dairy calves as part of a routine health check protocol. In addition, data regarding antimicrobial use (AMU), farm hygiene, and farm management were collected in order to identify possible risks for ESBL occurrence. Ten farms participated in the study with a median of 781 milking cows (319-1701). All calves investigated were younger than two weeks with an average age of 6.8 (±3.9) days. The farms were visited and samples were collected twice at an interval of 7-11 months. Faecal samples diluted 1:10, were plated onto BrillianceTM ESBL agar in duplicates. After 24 hours at 37°C, colonies were counted and total colony forming units (cfu)/ml calculated. Bacteria species were identified biochemically. ESBL-production was phenotypically confirmed using the MICRONAUT-S β-Lactamases system. Additionally, antimicrobial susceptibility was tested using VITEK® 2 technology. Phylotyping of E. coli isolates and screening for bla genes was performed by PCR. ESBL-producing enterobacteria were detected on all farms and 96.5% of calves investigated shed ESBL-positive bacteria. Of all ESBL-producing isolates, the majority were E. coli (92.9%), followed by Enterobacter cloacae (5.1%) and Klebsiella pneumoniae subsp. pneumoniae (2.0%). The majority of E. coli isolates was clearly assigned to phylogroup C (25.0%), followed by phylogroups A (15.2%) and E (14.1%). CTX-M group 1 was most frequently detected (80.4%). E. cloacae contained blaCTX-M and blaTEM or blaSHV. K. pneumoniae harboured blaSHV only. Besides resistance to penicillins and cephalosporins, the majority of isolates was also resistant to one or more antibiotic classes, with a high proportion being resistant against fluoroqinolones. 52.5% of isolates were further characterised as threefold multidrug resistant gram-negative bacteria (3MDR-GNB) according to the German Commission for Hospital Hygiene and Infection Prevention. None of the isolates were 4MDR-GNB, i.e. none revealed carbapenem-resistance. Penicillins were the most frequently administered antibiotics to calves on most farms and were the predominant substance class at herd level on all farms. Overall, the number of calves treated prior to sampling was rather low (11.7%). Analyses of data regarding the farm management identified weaknesses in biosecurity and cleaning and disinfection. Besides beta-lactam antibiotics being the most commonly used antibiotics no other risk factors could be identified. In summary, the prevalence of ESBL-carriers in dairy calves was exceptionally high and should be motivation to develop strategies for the reduction of multidrug-resistant bacteria in farm animals.