District-Wide Herd Sanitation and Eradication of Intramammary Staphylococcus aureus Genotype B Infection in Dairy Herds in Ticino, Switzerland

The present study demonstrates successful herd sanitation and eradication of contagious mastitis caused by Staphylococcus aureus genotype B (S. aureus GTB) in an entire Swiss district (Ticino) including 3,364 dairy cows from 168 farms. Herd sanitation included testing of all cows using a highly GTB specific and sensitive qPCR assay, implementation of related on-farm measures, appropriate antibiotic therapy of GTB-positive cows and culling of therapy-resistant animals, respectively. A treatment index was used as an objective criterion to select GTB-positive cows eligible for culling and replacement payment. 62 herds (37%) were initially GTB-positive with a cow prevalence between 10% and 100% and were submitted to sanitation. Twenty mo after the start of the campaign, all these herds were free from S. aureus GTB, whereby 73% of them were sanitized during the first 7 mo. At the cow level, a total of 343 animals were infected. 50 of them were immediately culled and financially compensated based on their treatment index value. The remaining 293 cows were intramammarily treated with antibiotics either during lactation using the combination of cephalexin-kanamycin or penicillin-gentamicin or at dry-off using cloxacillin. Out of these cows, 275 (93.9%) were treated successfully meaning that their milk was twice GTB-negative by qPCR after therapy. For lactational treatment, control samples were taken ≥10 and ≥20 d after treatment, for dry off treatment ≥14 and ≥24 d after parturition. Neither lactation number nor SCC before treatment of the cow nor the type of therapy were associated with therapeutic cure. Using data of 30 GTB-positive and 71 GTB-negative herds (1855 observations), the impact of GTB sanitation on bulk tank milk SCC (BTSCC) was evaluated applying a linear mixed statistical model. In the year before sanitation, BTSCC was always higher in GTB positive than in GTB negative herds. After the start of the campaign, BTSCC declined rapidly in the herds under GTB sanitation and achieved values that no longer differed statistically from those of GTB-free herds after only 2 mo, remaining very similar for the rest of the campaign. The farmers were very satisfied with the outcome of the campaign as all GTB positive herds could be sanitized rapidly, sanitation was sustainable, and milk quality increased.

[Risk factors for chronic perforating skin lesions in the area of the digits in cattle on Swiss alpine pastures]

INTRODUCTION

Diseases of the digits often occur in cattle on larger cattle mountain pastures. In the late spring 2020, at the time of the ascent of 1554 cattle to 11 high altitude alpine pastures in the Lower Engadine region, lesions in the area of the digits were clinically assessed and documented. 254 cattle were of non-cantonal and 1300 of local origin (Lower Engadine; postal code CH-75XX). Skin lesions in the area of the digits, identified as digital dermatitis (DD; Mortellaro's disease), were further classified according to the DD scoring system. Nonspecific skin lesions with clinical evidence of granulation tissue formation were termed chronic penetrating skin lesions (CPSL). At the end of the alpine pasturing season, in the early fall (descent of cattle from the alpine pastures), the procedure was repeated, and biopsies were taken from randomly selected cattle with CPSL. Digital dermatitis lesions were found in 34 of 1551 cattle at ascent, but no case of CPSL was found at that time. At descent, 19 of 1529 cattle had DD lesions and 88 cattle had CPSL. The clinical appearance of the CPSL was consistent with chronic skin lesions caused by penetrating skin lacerations. Histologically, the majority of the CPSL were classified as chronic hyperplastic dermatitis with granulation tissue formation. In all CPSL biopsies examined by PCR, Fusobacterium necrophorum and Porphyromonas levii, but neither Dichelobacter nodosus nor the tested Treponema species were detected. Fluorescence in situ hybridization revealed a negative result for Treponema species in all biopsies. In the regression analysis, cattle in the age group of 365 to 730 days had an increased risk for the presence of CPSL compared to the age group of 160 to 365 days (odds ratio (OR) = 4,95; confidence interval (CI) = 1,97-12,43). Holstein cattle had an increased risk of developing CPSL compared to Brown cattle (OR = 2,92; CI = 1,46-5,86) and cattle of non-cantonal origin showed a massively higher risk compared to local cattle (OR = 10,59; CI = 5,79 - 19,37). The statistically significant associations found in the present study can be taken into account in the selection of animals for summer pasturing on high altitudes in the future in order to reduce the prevalence of CPSL and consequently reduce the antimicrobial use. Spread of DD during the alpine pasturing season within the cattle groups examined was not found.

[Risk factors for infectious foot -disorders on two Swiss cattle -mountain pastures]

INTRODUCTION

In the present study, risk groups for infectious foot disorders were identified on two large Swiss cattle mountain pastures by analyzing animal and treatment data of a total of 3256 animals of the bovine species. Both mountain pastures were part of the Federal Office for Agriculture (FOAG) consultancy project «Healthy animals, attractive herdsmen positions and less medication on large cattle mountain pastures». The project was launched in 2020 following the increased incidence of lameness on these mountain pastures. Bacteriological and histological analyses were to provide information as to whether the most common foot disorder was interdigital phlegmon (IP) or whether digital dermatitis also occurred. Further, the temporal distribution of cases over the mountain pasture season and the influence of mountain pasture and year were investigated and interpreted for the project years 2020 to 2022, and treatment incidences were compared between years. Multiple treatment cycles in the same individual were classified into persistent infections and new infections. Nineteen of 394 first-treated cattle were clinically examined, 12 of them were additionally sampled for bacteriological and histological analyses. All cases examined showed, both clinically and following laboratory analyses, typical characteristics for IP. In contrast, there was no specific evidence for the presence of digital dermatitis. No persistent infections occurred during treatment with benzylpenicillin. Multivariate logistic regression analyses identified > 365-730-day-old cattle (odds ratio OR 8,29), as well as inseminated (OR 5,30) and non-inseminated (OR 7,85) heifers as risk groups for the disease studied (p < 0,05). Association with the oestrus activity of non-inseminated heifers and a generally higher locomotor activity in heifers compared to cows - with a correspondingly increased risk of injury - is conceivable. Meat breeds had a reduced risk compared to dairy breeds (OR 0,29). Breed differences in behavior and/or the effectiveness of the local immune response might have an impact. Knowing about these risk groups can be put to use in the future when selecting animals to be taken to the mountain pastures and/or when planning pasture management in order to reduce the prevalence of infectious foot disorders and thereby the use of antibiotics.

Effects of pediatric intensive care due to congenital heart defects on maternal mental health

AIM

Successful mother-child-bonding is a fundamental step for a healthy development of the child. Different factors like postpartum depression can hinder the bonding process. This study aimed to investigate how intensive care treatment due to congenital heart diseases of the infant alters bonding and how mothers cope with the situation.

METHODS

Validated questionnaires were used to analyze postpartum depression, mother-child bonding, stress factors and coping strategies for mothers at a pediatric intensive care unit (PICU; n=38) and a group of mothers without known psychiatric disorders attending a babywell visit with their child (n=91). Descriptive statistics and interaction models were calculated.

RESULTS

The PICU group showed on average higher total scores on the postpartum bonding questionnaire indicating mother-child bonding impairment and a higher proportion of mothers with severe depression was observed (76% versus 11%). The model showed a significant interaction between effective coping strategies and mother infant bonding (p = 0.04). Ineffective coping had no effect on bonding or depression in the PICU group.

CONCLUSION

Mothers of children treated at an ICU due a congenital heart disease are at increased risk for the development of depression and difficulties in different aspects of postpartum bonding. Our results show that coping mechanisms might significantly influence postpartum bonding. Implementation of tailored support is needed to optimize maternal outcomes.

[Implementation of biosecurity measures by hoof trimmers in Switzerland]

INTRODUCTION

Biosecurity in livestock farming includes all measures preventing pathogen introduction onto a farm (external biosecurity) and pathogen transmission on the farm itself (internal biosecurity). An important risk factor for the dissemination of infectious diseases are specialised external persons working on numerous farms, such as professional hoof trimmers in Switzerland. In the present study, 49 hoof trimmers, participating in the Swiss claw health programme and working as professionals, were questioned regarding their biosecurity measures and observed by two veterinarians during hoof trimming in order to assess the implementation of biosecurity measures by hoof trimmers. Data were processed using a scoring system, in which points were allocated to the different working methods taking into account their assumed transmission potential for infectious diseases such as digital dermatitis (DD) and Salmonellosis. The working method, which complied with the ideal biosecurity measure, was always given a whole point, whereas less optimal working methods were only given an intermediate value or no point. The scoring system helped identify precisely the strengths and weaknesses of the hoof trimmers in terms of biosecurity. The level of implementation of biosecurity measures by hoof trimmers was overall quite low (53 %=average of the overall biosecurity scores of the 49 hoof trimmers). Hoof trimmers which attended specialised training courses tended to have a higher level of implementation of biosecurity measures. The answers given by the hoof trimmers and the observations made by the veterinarians were compared, whereby it was found that hoof trimmers generally evaluated themselves better in regard to biosecurity than veterinarians assessed them. In summary and based on the results of this study, the dissemination of pathogens, such as DD associated treponemes and salmonella is possible during hoof trimming performed by external persons working on numerous farms. Thus, future training and continuing education courses should place emphasis on biosecurity.

Eye enucleation and exenteration in -cattle: a retrospective study of 38 cases (2013-2020)

INTRODUCTION

The study aimed to describe clinical indications for eye enucleation and exenteration, the occurrence of complications and long-term outcome in cattle, and examine owners' attitude towards enucleation and exenteration and their satisfaction with the surgical outcome. Medical records from the two veterinary teaching hospitals in Switzerland were reviewed to identify cattle that underwent unilateral enucleation or exenteration between January 2013 and December 2020. Data extracted included medical history, ocular examination, clinical diagnosis, surgical procedure including anesthesia, suture material and pattern used, complications, and treatment thereof. Long-term follow-up was evaluated via national animal database inquiries to determine survival time and via owners' interviews with the use of a standardized questionnaire that included questions regarding the occurrence of complications and reason for culling, production performances and perceived quality of life after surgery, concerns, factors affecting the decision to proceed with surgery, and general satisfaction with the outcome. Descriptive statistics, Fisher's exact tests and unpaired t-test were used to summarize the data and assess association between variables. Association was considered significant if p < 0,05. Thirty-eight cases were identified, with a median age of 5 years. More than half of the cases (55,3 %) were diagnosed with non-neoplastic ocular lesions represented by severe trauma with loss of globe content, globe rupture with history of infectious keratoconjunctivitis or hypopyon, or congenital malformations. The remaining cases were diagnosed with neoplastic lesions, including ocular squamous cell carcinoma (OSCC), melanoma, or sarcoma. Complications following surgery were reported in 29 % of cases and included postoperative infection and recurrence of OSCC. There was no significant association between ocular diagnosis and the occurrence of postoperative complications or survival time. Surgery did not seem to influence the animals' postoperative production performance or the perceived quality of life. Most owners (92 %) were satisfied with the surgical outcome. The occurrence of postoperative complications leading to increased overall costs and culling was the main reason for lower owner satisfaction.

Effects of the anti-sucking device «SuckStop Müller» on calf behavior

INTRODUCTION

When cross-sucking persists beyond calf-hood, it represents an important problem in dairy heifers and cows. It can cause teat injuries and severe mastitis and lead to significant economic losses. The «SuckStop Müller,» a novel anti-sucking device, is designed to give the calf a negative feedback when cross-sucking on a conspecific. The aim of this study was to assess whether wearing a SuckStop would result in behavioral changes other than cross-sucking and thus, impair welfare in the short- and longer-term. Sixteen group-housed calves were observed in groups of four on five days, before and after fitting the SuckStop: day -2, day -1, day 0, day 1, and day 9. Maintenance behaviors (e.g., feeding, drinking, lying) were recorded using instantaneous scan sampling. In addition, the frequency of contact behaviors (e.g., exploring the feeding fence, touching own body) was recorded by means of continuous focal animal observations. Contact behaviors were classified as «impaired» or «normal» depending on whether or not the calf flinched in response to the contact. Finally, the number of visits to the milk and concentrate feeders was extracted from the computer-controlled feeding system. Fitting a SuckStop resulted in a higher proportion of observations spent lying and less exploration behavior on day 0 and day 1 than on day -2, day -1, and day 9. On day 0 and day 1, 6,3 % of exploration behaviors were classified as impaired, compared to 0,4 % (day -2, day -1) before and 0,2 % (day 9) after fitting the SuckStop. On day 9, all calves had superficial ulcerations on the nasal septum. In four calves, these ulcerations were moderately severe, whereas all other calves had slight ulcerations. In summary, the calves habituated quickly to this novel anti-sucking device. Follow-up studies are necessary to assess the long-term relevance of tissue alterations in the nasal septum for calf welfare as well as the effect of the SuckStop on cross-sucking behavior.

[Non-antibiotic treatment of interdigital hyperplasia secondary infected with digital dermatitis treponemes in dairy cows]

INTRODUCTION

Since the spread of classical digital dermatitis (DD) lesions within the cattle population, frequency of infections of interdigital hyperplasia (IH) lesions with DD-associated Treponema spp. (IH+DD) increased. The aim of the present case series is to describe an alternative treatment technique to surgical lesion removal or local treatment of HI+DD lesions with antibiotics. In this report, the effect of repeated local administration of salicylic acid paste, protected by a water repellent bandage was described and assessed for the treatment of four dairy cows with IH+DD lesions. Milker's fat Eutra was applied to the unaffected skin adjacent to the lesion to protect healthy skin from the keratolytic properties of salicylic acid paste. Treatment was repeated at weekly intervals in all four cases until the IH+DD lesions had completely clinically healed. Two cows additionally showed classical DD lesions between the heels. Clinical healing was defined as remission of IH and complete healing of the DD lesions located on IH lesions and between the heels. Complete healing was evident at three weeks of treatment in all four cases. Weekly repeated topical application of salicylic acid paste under bandage may be recommended as an alternative to surgical or antibiotic treatment of IH+DD lesions.

[Prevalence of claw disorders in swiss cattle farms]

INTRODUCTION

The project «Healthy claws - the foundation for the future» aims to establish a Swiss national claw health monitoring based on digital recordings by claw trimmers during claw trimming. To assess claw health on the participating farms, between-herd prevalence, within-herd prevalence and cow prevalence of all claw disorders based on the «ICAR Claw Health Atlas» were calculated during this study. Claw trimmers underwent an intensive training and examination in order to ensure data quality. To guarantee the representativity of the prevalences, only farm claw trimmings were considered, where ≥ 80 % of the cows in a herd were trimmed. The calculations were based on 7108 cows and 403 heifers from 238 farms, during the period from February 2020 to February 2021. At least one claw disorder was present in 99,2 % of the farms, with 49,6 % of the heifers and 77,7 % of the cows having at least one claw disorder. The high prevalence is seen as a result of all ICAR claw disorders being considered, whereas not all of them are painful and consequently not all of them cause lameness. The absence of lameness assessment limits the evaluation of existing herd problems. High between-herd and cow prevalences were observed for the following claw disorders: heel horn erosion (92,9 %/64,7 %), digital dermatitis (55,9 %/20,7 %), white line disease (81,5 %/17,7 %) and sole hemorrhage (66,4 %/11,6 %). Asymmetric claws, corkscrew claws, scissor claws, horn fissure, interdigital phlegmon, swelling of the coronet and/or bulb and toe necrosis had low prevalences. The proportion of cows treated with a hoof block (0,5 %) was comparatively small in regard of the cows suffering from ulcers (5,6 %) and white line abscesses (2,5 %). The median within-herd prevalence of digital dermatitis was 5,6 %, with a maximal within-herd prevalence of 87,5 %. Despite the contagious nature of digital dermatitis, no increase of between-herd and cow prevalence has been observed in the past ten years throughout Switzerland. Based on this data, the Swiss claw health situation can be monitored, compared over time and improved in the future.

[The lying and rumination behavior of healthy dairy cows housed in tie stalls is associated with bedding depth]

INTRODUCTION

The lying and rumination behavior of dairy cows is internationally used as an animal welfare indicator. Dairy cow housing in Switzerland is subordinated to detailed legal requirements. It is particularly described that the lying area for cows must be covered with a sufficient amount of bedding. In the current study, we investigated whether bedding depth influences the lying and rumination behavior and thus, the animal welfare of healthy dairy cows housed in tie stalls. Bedding depth was categorized as ≤ 2 cm and > 2 cm. The lying and rumination behavior of 145 cows from 33 farms was recorded and analyzed considering farm effects; 105 cows were housed on ≤ 2 cm bedding, and 40 cows on > 2 cm bedding. Cows on > 2 cm bedding had on average a one hour longer daily lying time compared with cows on ≤ 2 cm bedding (mixed-effects linear regression: mean difference [cows on > 2 cm bedding - cows on ≤ 2 cm bedding] = 60,7 min/d; standard error = 28,6 min/d; p-value = 0,037). The odds of a cow to lie while ruminating were significantly higher in cows on > 2 cm bedding against cows on ≤ 2 cm bedding (mixed-effects logistic regression: Odds ratio = 1,27; CI95% [1,17-1,38]; p-value  2 cm can make a significant difference in the lying and rumination behavior of healthy dairy cows housed in tie stalls. Consequently, the animal welfare of dairy cows in tie stalls is improved by providing at least 2 cm of bedding.

[Comparative economic analysis of the new concept for veal calf fattening «outdoor veal calf» and the conventional IP-SUISSE label]

INTRODUCTION

The evaluation of new animal husbandry concepts includes, beyond the exploration of chosen parameters, that the question is addressed whether economic benefits for producers and ethical benefits for society result of the new system when compared to traditional systems. In a previous study, a novel management and housing concept for veal production («outdoor veal calf», OVC) was tested from October 2016 to July 2018. The OVC concept was associated with distinctly lower antimicrobial use while average daily weight gain was similar and calf welfare better; furthermore mortality was lower compared to conventional label fattening. The aim of the present study was to compare economics between the OVC concept on intervention farms (IF) and the IP-SUISSE label concept on control farms (CF) by calculating contribution margins (CM). The CM indicates the difference between the performance of a production branch (e. g. slaughter return) and the allocable costs for this production branch (e. g. feed costs). In the present study, two different approaches were used for CM calculation to analyze the available data in detail. No substantial differences in CM between the OVC concept and the IP-SUISSE concept were found in either approach. However, the specific CM varied between the approaches as different calculation criteria for quantities and prices were applied (approach «real» with accurate costs and returns from the OVC study and approach «standardized» with costs and returns based on the CM catalogue). The CM varied slightly for the CM per man-hour (IF «real»: 6.96 CHF/man-hour, «standardized»: 4.49 CHF/man-hour; CF: 7.90 CHF/man-hour and 8.08 CHF/man-hour, respectively) and considerably for the CM per fattening space and year (IF «real»: -380.36 CHF, «standardized»: -559.50 CHF; CF: -244.70 CHF and -318.80 CHF, -respectively). Producing veal with the OVC concept -allowed for achieving comparable CM/man-hour as in conventional label production. Thus, the farmers' economic interests should be warranted when implementing the OVC concept.

[Evaluation of a novel training course for hoof trimmers to participate in a Swiss national cattle claw health monitoring programme]

INTRODUCTION

The main goal of the resources project «Healthy claws - the foundation for the future» is to establish a Swiss national claw health monitoring programme for cattle, similar to what has already been established in other countries (e. g. Finland, Sweden). So far in the course of the project, 30 claw trimmers have been trained to use a digital recording software. An appropriate training concept and information to the work environment of Swiss claw trimmers are necessary to ensure that the recorded claw health data is of good quality. The newly developed training programme for claw trimmers was evaluated using the 30 first trained claw trimmers of the project. The training consisted of group events and individual schooling sessions, during which the claw trimmers were trained to recognise, classify and digitally record foot and claw disorders according to the «ICAR claw health atlas». At the end of the training programme, demographic and work relevant data about the claw trimmers was collected and their abilities when using the recording software, as well as recognising and classifying foot and claw disorders using pictures or live animals, were evaluated. The demographic and work relevant data collected at the end of the training showed an ageing of the profession (43% of the participants were over 50 years old), a lack of full-time claw trimmers (23% of the claw trimmers worked 90% or 100%), a neglect of locomotion scoring during claw trimming (no locomotion scoring standing from 60% and in movement from 33% of the participants) and a broad use of the Swiss claw trimming method (90% of the claw trimmers indicate using this method). An average Cohens kappa value of 0,74, and thus an overall substantial agreement with the first author, respectively the ICAR Atlas, was achieved for the identification and classification of foot and claw disorders. It was also noted, that all the participants were capable of using the recording software in practice after their schooling. The calculation of Cohens kappa values helps to recognise claw trimmers which fall below the limiting value and therefore show an insufficient agreement. These claw trimmers can thus be excluded from the scientific evaluation or undergo further training. It was concluded that the described training concept is suitable to establish a national claw health monitoring programme.

[Establishment of key indicators and limit values for assessment of claw health of cattle in Switzerland]

INTRODUCTION

Herd medicine is a field of buiatrics characterized by regular and systematic visits by the veterinarian to improve the health and performance of the animals, the quality of animal products and finally the satisfaction of the farm staff. Internationally established key indicators, such as age at first calving, heat recognition rate or the percentage of cows with clinical mastitis per month (%),26 have been available for a long time in the areas of fertility and udder health. These key indicators help veterinarians to recognize and define health problems at herd level at an early stage and to work out measures for their improvement. Such key indicators are currently lacking in the field of claw health, hence making standardized identification of problem farms considerably more difficult. Considering the permanent negative influence of claw health problems on fertility, performance and overall animal welfare, it becomes clear how valuable claw health indicators will be in the future. The aim of this study was, therefore, to develop both primary and secondary indicators of claw health and to define corresponding limit values for Switzerland. Based on a literature search, several primary and secondary indicators were developed (1˚K: Herd problem Yes/No, 2˚K: Classification of the problem). These were discussed in an expert panel consisting of practicing veterinarians, staff of the Swiss bovine herd health service and university professors with regard to their possible practical implementation and relevance. Finally, 3 primary and 10 secondary indicators were judged to be suitable to assess a herd with regard to claw health. The primary key indicators were: proportion of cows leaving the herd due to a claw problem, proportion of lame cows of a herd, and proportion of cattle with at least one claw disease. The corresponding provisional limit values (exceeding the value = problem) for Switzerland were worked out by means of surveys among farmers, hoof trimmers, veterinary students and veterinarians. In addition, recommendations from the literature and current prevalence studies were used to adapt the defined limit values to the situation on Swiss farms. In the coming years, the claw health project «Gesunde Klauen - das Fundament für die Zukunft» will collect current prevalence values of claw diseases, and the limit values will then be adjusted and specified accordingly.

Foot health and prevalence of Dichelobacter nodosus in 11 ungulate species at Berne Animal Park

INTRODUCTION

Dichelobacter nodosus (D. nodosus) is the etiological agent of ovine footrot affecting mainly sheep worldwide, but also free-ranging wild ungulates such as Alpine ibex (Capra ibex ibex) and mufflon (Ovis orientalis orientalis). A nationwide ovine footrot eradication program is planned for the years to come, based on polymerase chain reaction (PCR)-testing of interdigital swab samples and regular footbathing. In this cross-sectional study, we clinically evaluated the foot health and analysed presence of D. nodosus in 11 different even-toed ungulate species (mainly European species) during a 13 months (2018-2019) period in Berne Animal Park. The foot lesions were scored for any clinical signs of pathologies as described in cattle and simultaneously for clinical signs of footrot as described for sheep, using a scale from 0 to 5 (while 0 describes clinically healthy feet and 5 loss of the horn capsule). From a total of 53 animals, 4-feet swab samples were taken from the interdigital cleft and subjected to real-time PCR assays to detect D. nodosus at animal level. Foot lesions were detected in five different species. In 3/5 muskoxen (Ovibos moschatus wardi), 7/12 Cretan wild goats (Capra hircus cretica) and 2/3 dwarf goats (Capra hircus aegagrus), they mainly consisted of white line disease, whereas in 9/10 European bison, dermatitis of the interdigital cleft was diagnosed. 1/3 alpaca was diagnosed with chorioptic mange of the heel area. None of the examined animals showed clinical signs of footrot (score 0), and neither benign (aprB2-positive) nor virulent (aprV2-positive) D. nodosus were detected in any of the samples. This study provides additional information to facilitate an efficient ovine footrot control program in Switzerland and suggests that captive wild even-toed ungulates do not pose a risk to the planned footrot control program.

[Improvement of claw health of cattle in Switzerland]

INTRODUCTION

The modern technique of cattle hoof care was founded by E. Toussaint Raven in 1977. Environmental risk factors on cattle claws altered in the past 43 years. The change from free ranging to indoor housing, the intensified feeding and the breeding towards traits of high performance have significantly increased the mechanical and chemical stress on the claws. In modern free-stalls, dairy cows are required to walk on hard flooring to feed, drink and get milked. Good hoof health is a basic requirement for cattle welfare. Professional and regular hoof trimming is still considered the most effective measure to promote hoof health in dairy cattle. In order to meet today's requirements and to promote claw health, the Swiss Hoof Trimmers Association (SKV), in collaboration with the Vetsuisse faculties, Universities of Berne and Zurich, and the Bovine Health Service (RGD, Bern) developed and described the Swiss technique of functional claw trimming. The aim was to establish a consistent method, which takes into account the size and bodyweight of the modern cow, the anatomical and physiological characteristics of their claws and includes adaptations counteracting very relevant diseases such as digital dermatitis. The result is a workflow described and illustrated with coloured pictures and consisting of five individual steps based on the technique of E. Toussaint Raven, Additionally, the upcoming Swiss national resource project on long-term improvement of claw health is presented in some detail. The key point of this project is the electronic documentation of clinical findings by the trained professional claw trimmers. This data will later (i) be used to assess the foot health of Swiss cows, (ii) allow to determine the prevalence of foot diseases of cattle in Switzerland and (iii) to monitor the effect of the implementation of foot health concepts. The aim of this work is to combine the findings from science and the practical experience of hoof trimmers in one method, to standardize the applied hoof care in Switzerland and to adapt it to today's hoof health requirements.

Short communication: Claw block application improves locomotion and weight-bearing characteristics in cattle with foot diseases

In cattle with foot diseases, application of a block on the healthy partner claw is a common method of pain relief. The aim of this study was to evaluate the effect of wooden claw blocks on locomotion characteristics and weight distribution in healthy (group C; n = 17) versus lame (group L; n = 17) cattle. Group L was further subdivided into group L1 (lameness score ≤3; n = 7) and group L2 (lameness score >3; n = 10). We performed lameness scoring using a numeric rating system and measured locomotion characteristics using 2 accelerometers (400 Hz; kinematic outcome = stance phase duration; kinetic outcomes = foot load and toe-off) and a 4-scale weighing platform (difference of mean weight distribution across the limbs; ∆_weight) before and after application of a claw block. We applied claw blocks to a randomly assigned lateral or medial claw of the fore or hindlimb in group C cows, and on the healthy partner claw in group L cows. Variables were expressed as differences across limbs. We used 1-way ANOVA to determine the differences between groups C and L and between groups L1 and L2 for ∆_weight after application of the claw block. We performed paired t tests to compare variables before and after application of the claw block in groups C and L. Group L scored higher on the numeric rating system than group C (mean ± SD, 3.40 ± 0.62 vs. 1.87 ± 0.28) and showed greater differences in relative stance phase duration (16.34 ± 10.78% vs. 2.13 ± 1.94%), foot load (9.68 ± 8.06 g vs. 3.26 ± 3.69 g), toe-off (3.91 ± 3.14 g vs. 0.78 ± 0.66 g), and ∆_weight (53.62 ± 28.85% vs. 8.52 ± 6.19%). In group C, we observed an increase of 12.17 percentage points in ∆_weight after block application, from 8.52 ± 6.19% to 20.69 ± 17.01%. Compared with the baseline, group L showed a decrease in numeric rating system score (2.88 ± 0.49 vs. 3.40 ± 0.62) and a decrease in differences between the limbs in relative stance phase duration (7.66 ± 9.96% vs. 16.34 ± 10.78%) and foot load (4.26 ± 4.14 g vs. 9.68 ± 8.06 g) after application of a claw block. Group L2 showed smaller ∆_weight after application of a claw block than group L1 (-7.8 ± 8.7% vs. 10.4 ± 7.6%). After block application in group L, we observed smaller differences across the limbs in variables measured to describe gait-cycle characteristics while walking, but no significant improvement while standing. We concluded that application of a claw block must be combined with other methods of pain relief, such as analgesic medication.

Resting state networks of the canine brain under sevoflurane anaesthesia

Resting-state functional Magnetic Resonance Imaging (rs-fMRI) has become an established technique in humans and reliably determines several resting state networks (RSNs) simultaneously. Limited data exist about RSN in dogs. The aim of this study was to investigate the RSNs in 10 healthy beagle dogs using a 3 tesla MRI scanner and subsequently perform group-level independent component analysis (ICA) to identify functionally connected brain networks. Rs-fMRI sequences were performed under steady state sevoflurane inhalation anaesthesia. Anaesthetic depth was titrated to the minimum level needed for immobilisation and mechanical ventilation of the patient. This required a sevoflurane MAC between 0.8 to 1.2. Group-level ICA dimensionality of 20 components revealed distributed sensory, motor and higher-order networks in the dogs’ brain. We identified in total 7 RSNs (default mode, primary and higher order visual, auditory, two putative motor-somatosensory and one putative somatosensory), which are common to other mammals including humans. Identified RSN are remarkably similar to those identified in awake dogs. This study proves the feasibility of rs-fMRI in anesthetized dogs and describes several RSNs, which may set the basis for investigating pathophysiological characteristics of various canine brain diseases.

Effects of the novel concept 'outdoor veal calf' on antimicrobial use, mortality and weight gain in Switzerland

The aim of the intervention study 'outdoor veal calf' was to evaluate a novel concept for calf fattening which aimed at reducing antimicrobial use without compromising animal health. Management practices such as commingling of calves from multiple birth farms, crowding, and suboptimal barn climate are responsible for high antimicrobial use and mortality in the veal calf population. The risk of selecting bacteria resistant to antimicrobials and of economic losses is accordingly elevated. The 'outdoor veal calf' concept, implemented in nineteen intervention farms (IF), is based on three main measures: 1. purchased calves are transported directly from neighboring birth farms to the fattening facility instead of commingling calves in livestock dealer trucks; 2. each calf is vaccinated against pneumonia after arrival and completes a three-week quarantine in an individual hutch; and 3. the calves spend the rest of the fattening period in outdoor hutches in groups not exceeding 10 calves. The covered and bedded paddock and the group hutches provide shelter from cold weather and direct sunshine, constant access to fresh air is warranted. Nineteen conventional calf fattening operations of similar size served as controls (CF). Every farm was visited once a month for a one-year period, and data regarding animal health, treatments, and production parameters were collected. Treatment intensity was assessed by use of the defined daily dose method (TI_DDD in days per animal year), and calf mortality and daily weight gain were recorded in both farm groups. Mean TI_DDD was 5.3-fold lower in IF compared to CF (5.9 ± 6.5 vs. 31.5 ± 27.4 days per animal year; p < 0.001). Mortality was 2.1-fold lower in IF than in CF (3.1% ± 2.3 vs. 6.3 % ± 4.9; p = 0.020). Average daily gain did not differ between groups (1.29 ± 0.17 kg/day in IF vs. 1.35 ± 0.16 kg/day in CF; p = 0.244). A drastic reduction in antimicrobial use and mortality was achieved in the novel 'outdoor veal calf' system without compromising animal health. The principles of risk reduction used in designing the system can be used to improve management and animal health, decrease the need for antimicrobial treatments and thus selection pressure on bacteria in veal operations.

The prevalence of Dichelobacter nodosus in clinically footrot-free sheep flocks: a comparative field study on elimination strategies

Background

Ovine footrot caused by Dichelobacter nodosus (D nodosus) is an infectious disease affecting sheep worldwide. Switzerland plans a nationwide footrot eradication program, based on PCR-testing of interdigital swab samples. The aim of this study was to test for the presence of D nodosus in clinically footrot-free sheep flocks which had been subjected to different treatment strategies, to assess whether they were feasible for the eradication process, especially focussing on antimicrobial flock treatments. Clinical scoring and PCR-results were compared. Ten farms had used hoof bathing and hoof trimming without causing bleeding, ten had used individual treatments and flock vaccines to gain the free status and ten had become free through whole-flock systemic macrolide treatment. For every farm, three risk-based collected pool samples were analysed for the occurrence of virulent and benign D nodosus by PCR detection of aprV2/aprB2.

Results

Six flocks from any treatment group tested positive for aprB2 in all pools. Clinical signs were absent at the time of sampling, but some flocks had experienced non-progressive interdigital inflammation previously. Two flocks tested aprV2-positive in the high-risk pool. One of them underwent a progressive footrot outbreak shortly after sampling. Individual retesting indicated, that virulent D nodosus most likely was reintroduced by a recently purchased ram. In the second flock, a ram was tested positive and treated before clinical signs occurred.

Conclusions

All treatment strategies eliminated the causative agent and were found to be suitable for implementation in the PCR-based eradication process. PCR-testing proved to be more sensitive than visual scoring, as it also detected clinically healthy carriers. It will be of benefit as a diagnostic tool in elimination and surveillance programs.

Early Infection Dynamics of Dichelobacter nodosus During an Ovine Experimental Footrot In Contact Infection

INTRODUCTION

Ovine footrot caused by Dichelobacter nodosus is a highly contagious and painful disease representing an economic as well as an animal welfare problem. In order to get more information on the infection dynamics, 26 lambs and 4 ewes enrolled in an in-contact infection trial were monitored over two weeks for the presence of D. nodosus-specific DNA. Two D. nodosus-positive ewes were housed together with 13 confirmed negative lambs. The control group consisted of another 13 lamb siblings and two confirmed D. nodosus-negative ewes. Every foot of all sheep was sampled seven times over the two weeks experiment period and subsequently analyzed for the presence of D. nodosus by quantitative real-time PCR. The control group was negative at the beginning and the end of the experiment and showed no clinical symptoms of footrot. The two positive ewes showed a high, but hundred fold differing level of virulent D. nodosus that remained constant over time with one of the ewes being also weakly positive for benign D. nodosus. All lambs of the infection group were positive for virulent D. nodosus at 14 days post infection (dpi). The first positive animals were observed on 3 dpi. The D. nodosus load remained at a low level and only increased in a few lambs at the end of the trial. Five of the contact lambs showed suspicious clincal signs (score 1-2) at 14 dpi corroborating the PCR results and indicating that the disease starts as early as two weeks after contact with positive sheep.

[Objective assessment of udder filling degree in diary cattle during shows]

INTRODUCTION

Overbagged udders are commonly seen at dairy cow shows in Switzerland and abroad due to prolonged milking intervals. In recent years various studies documented the negative effects of prolonged milking intervals and examined the objectivity of an ultrasound-based assessment scheme for determining udder filling. In addition, risk factors were calculated which lead to udder edema outside the puerperal phase. For example, the effects of a sudden increased 24-hour milking interval were altered behavior (reduced feeding time, increased rumination time) and a significantly increased cell count in experimental cows. Edema formation was observed sonographically in the subcutaneous udder tissue at the sites of predilection known from previous studies. No evidence of edema was observed in cows milked at 12 hour intervals. Based on these results, a new scoring system was defined using ultrasound images of show cows (grade 0 = no edema, grade 1 = slight, grade 2 = moderate, grade 3 = severe edema). Results documented that experienced clinicians were able to score ultrasound images reliable (interobserver reliability κ = 0.815, three different clinicians; intraobserver reliability κ = 0.90 and κ = 0.85, two clinicians) and little variability existed between the clinicians. A prolonged milking interval was identified as the main risk factor. Modified Swiss Dairy Show Regulations were implemented by January 1st, 2018 and ultrasonographic examinations proofed to be reliable in practice. Since January 1st, 2019 visual scoring of the udder filling is evaluated as part of a pre-show inspection. The sonographic evaluation can be used as a reliable diagnostic addition.

[Footbath as treatment of footrot in sheep. Current -situation on Swiss sheep farms]

INTRODUCTION

Footrot in sheep should be eradicated in Switzerland in the future. Based on scientific findings, this can be achieved with disinfectant footbaths. It is unknown how many sheep farmers are already using this means and how it is used. The current study evaluated the farm operation, the design of the footbath, the use of disinfectants and footbath with a written survey of a representative sample of all sheep farmers. The sample population was selected randomly, however stratified by language region and herdsize to control for differences between these groups. 45.3% (n=1134) of the distributed questionnaires were received for evaluation. On average 32.8% of the respondents used a footbath. Even on large farms (> 50 animals), which were more frequently affected by footrot, a footbath was available only in 52.6% of the farms in the French-speaking part and 67.7% in the German/Italian speaking part of Switzerland. The footbaths were correctly applied in most respects (e.g., pre-claw cleaning, liquid level and concentration of disinfectants, time in the footbath, post-bath drying phase) in the current study. Most commonly mobile plastic baths were in use. The disinfectants used were mainly formalin, copper and zinc sulfate. The incorrect disposal of the heavy-metal containing copper and zinc sulfate solutions was identified as an important problem: In 59% of the sheep farms the remaining footbath solutions were disposed in the slurry pit or manure storage. In summary the current study recommends (i) to motivate sheep farmers to use a footbath for the treatment and prevention of footrot, and (ii) to replace the currently used disinfectants with substances that are non-toxic to humans, animals and the environment.

Evaluation of arterial digital blood flow in dairy cows with claw horn disruption lesions using Doppler ultrasonography

Vascular changes play an important role in the pathogenesis of claw horn disruption lesions in cattle. The aim of the study was to measure arterial blood flow in the hind limbs of German Holstein cows with claw horn disruption lesions. A 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the dorsal pastern region in the hind limbs of 11 non-lame and 33 lame German Holstein cows in which lameness was scored clinically. Qualitative and quantitative blood flow parameters were compared in affected limbs and unaffected contralateral hind limbs in lame cows and in the hind limbs of lame cows and non-lame cows. A pulsed-wave Doppler signal suitable for analysis was obtained in 78 of 88 limbs (33 affected and contralateral limbs, 22 limbs of control cows). Blood flow curve types 1 and 2 were predominant in the hind limbs of lame cows. Vessel diameter, end-diastolic velocity, and blood flow rate were significantly greater in lame cows than in non-lame cows and were numerically greater in moderately lame cows than in mildly lame cows. The differences in the qualitative and quantitative parameters between lame and non-lame cows were most likely caused by inflammation of the pododerm. The role of weight distribution between the paired hind limbs and the existence of claw horn disruption appeared to have an effect on the differences in local circulation in the affected and unaffected contralateral hind limbs in lame cows.

Evaluation of arterial digital blood flow in dairy cows with claw horn disruption lesions using Doppler ultrasonography

Vascular changes play an important role in the pathogenesis of claw horn disruption lesions in cattle. The aim of the study was to measure arterial blood flow in the hind limbs of German Holstein cows with claw horn disruption lesions. A 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the dorsal pastern region in the hind limbs of 11 non-lame and 33 lame German Holstein cows in which lameness was scored clinically. Qualitative and quantitative blood flow parameters were compared in affected limbs and unaffected contralateral hind limbs in lame cows and in the hind limbs of lame cows and non-lame cows. A pulsed-wave Doppler signal suitable for analysis was obtained in 78 of 88 limbs (33 affected and contralateral limbs, 22 limbs of control cows). Blood flow curve types 1 and 2 were predominant in the hind limbs of lame cows. Vessel diameter, end-diastolic velocity, and blood flow rate were significantly greater in lame cows than in non-lame cows and were numerically greater in moderately lame cows than in mildly lame cows. The differences in the qualitative and quantitative parameters between lame and non-lame cows were most likely caused by inflammation of the pododerm. The role of weight distribution between the paired hind limbs and the existence of claw horn disruption appeared to have an effect on the differences in local circulation in the affected and unaffected contralateral hind limbs in lame cows.

Detection of specific Treponema species and Dichelobacter nodosus from digital dermatitis (Mortellaro's disease) lesions in Swiss cattle

INTRODUCTION

The aim of this study was to determine the prevalence of the three Treponema species as well as D. nodosus in Digital dermatitis (DD) and slurry of Swiss cattle using PCR. A total of 86 specimens from 24 farms were enrolled in the study. Slurry samples from 21 DD-affected and one unaffected farm were collected to assess the potential of environmental transmission. Nested and real-time PCR were performed from the specimens to detect Treponema species and D. nodosus, respectively. The DD-stages were positive for at least one or more of the DD-associated Treponema species in 50 of 61 cases (82.0%) and in 9 of 25 cases (36.0%) in unaffected animals. Infected animals with small focal active lesions showed a significantly lower prevalence (14.8%) compared to the other DD stages (67.2%; P=0.011). Most prevalent was T. phagedenis (65.1%). D. nodosus was detected in 51.8% of clinical DD lesions and 24.1% in unaffected cases, but its presence was not significantly associated with the various DD-stages. All samples positive for D. nodosus contained the acid protease gene aprB2 but were negative for aprV2, the latter associated with virulence in sheep foot rot. Control farms were negative for all DD-associated Treponema species while positive for aprB2 and negative for aprV2. The presence of aprB2 suggests it is ubiquitous in the animal environment. With respect to the slurry samples, three out of 21 specimens (14.3%) were positive for one or more of the DD-associated Treponema species and eleven out of 21 specimens (52.4%) were positive for aprB2 and negative for aprV2 of D. nodosus. In conclusion, an association was found between the presence of clinical DD and specific Treponema species, while for D. nodosus no such link with DD lesions could be observed.

Short communication: Risk factors for sonographically detectable udder edema in overbagged cows at dairy shows

At dairy cow shows, the appearance of the udder is very important. To show cows at their best, udders are often presented in an overbagged state by extending milking intervals before the show. This practice represents an animal welfare issue because it is associated with behavior changes (e.g., excessive abduction and decreased eating time) and may affect the health of the animal. The aim of the current study was to determine the association between various parameters (e.g., milk yield, days in milk, milking procedures, or administration of nonsteroidal anti-inflammatory drugs, steroids, or diuretics) and the sonographically detectable udder edema score. Data were collected from the show catalogs, by interviewing the exhibitors, by analyzing official veterinary treatment protocols and official milking data, via laboratory analysis of blood samples, and by sonographic examinations of the udders at the show. For sonographically detectable udder edema scoring, 3 scans were taken, 1 on each fore quarter and 1 incorporating both rear quarters at the level of the median suspensory ligament. For grading the scans, a scoring system of 4 grades (score 0 = no edema, 1 = slight edema, 2 = moderate edema, 3 = severe edema) was used. Data from 321 cows of different breeds were collected at 4 highly competitive Swiss dairy shows (shows A-D) between January and September 2017. To determine risk factors for sonographically detectable udder edema, data were analyzed with 2 different logistic regression models. In model 1, the odds ratios were 3.33 (milking intervals of ≥16 h vs. <14 h), 3.84 (show A vs. show C), and 7.39 (dairy breeds vs. dual-purpose breeds). Milking intervals of dairy breeds were significantly higher than those of dual-purpose breeds. In model 2, milking interval was the only significant risk factor with an odds ratio of 9.00 for milking intervals of ≥16 h. Only the milking intervals represented a relevant risk factor in both models; therefore, we concluded that the previously described sonographic udder edema scoring is a useful technique for detecting overbagged udders at dairy shows. Its routine implementation may improve cow welfare at dairy shows.

Tail walking in a bottlenose dolphin community: the rise and fall of an arbitrary cultural 'fad'

Social learning of adaptive behaviour is widespread in animal populations, but the spread of arbitrary behaviours is less common. In this paper, we describe the rise and fall of a behaviour called tail walking, where a dolphin forces the majority of its body vertically out of the water and maintains the position by vigourously pumping its tail, in a community of Indo-Pacific bottlenose dolphins (Tursiops aduncus). The behaviour was introduced into the wild following the rehabilitation of a wild female individual, Billie, who was temporarily co-housed with trained dolphins in a dolphinarium. This individual was sighted performing the behaviour seven years after her 1988 release, as was one other female dolphin named Wave. Initial production of the behaviour was rare, but following Billie's death two decades after her release, Wave began producing the behaviour at much higher rates, and several other dolphins in the community were subsequently sighted performing the behaviour. Social learning is the most likely mechanism for the introduction and spread of this unusual behaviour, which has no known adaptive function. These observations demonstrate the potential strength of the capacity for spontaneous imitation in bottlenose dolphins, and help explain the origin and spread of foraging specializations observed in multiple populations of this genus.

[The significance of cryptosporidiosis for the health of calves in Switzerland]

INTRODUCTION

Diarrhea in calves is one of the most important cattle diseases in Switzerland. The diagnosis and treatment of calf diarrhea represent a major challenge. Single-celled Cryptosporidium parasites are the most prevalent causative agents of calf diarrhea besides rotavirus in the first weeks of life, and are responsible for about 50% of diarrheal cases. Cryptosporidium parvum has been described as a cause of diarrhea in one to three weeks old calves since the 1970s. Oral ingestion of persistent environmental oocysts results in severe diarrhea lasting four to six days and shedding of large numbers of infectious oocysts. A tiny amount of 10 oocysts is already sufficient to cause disease. Detailed knowledge about the epidemiology and virulence of the different C. parvum strains is still lacking. In addition, current diagnostic tests cannot reliably distinguish between non-pathogenic (e.g. C. bovis) and pathogenic Cryptosporidium species. Until now, no effective therapeutic drug or vaccine against calf cryptosporidiosis has been found. Water-borne epidemics and the zoonotic potential of Cryptosporidium in immunodeficient patients are of great medical importance. The increasing number of cryptosporidiosis cases associated with high infant mortality in less industrialized and impoverished regions (including South-East Asia and sub-Saharan Africa) has intensified the research in recent years. The recent discoveries of new therapeutics against C. parvum may benefit calf medicine in the near future. This review article reports on these new developments, highlights calf cryptosporidiosis in Switzerland and draws attention to a new research project.

[AntibioticScout.ch: Decision support for the prudent use of antimicrobials: Application in cattle]

INTRODUCTION

The administration of antibiotics in livestock has been criticized for many years, in particular because of an inappropriate use and the appearance of antibiotic residues in the environment, which can promote the emergence and spread of resistant bacteria. However, antibiotics are essential for the successful and sustainable control of bacterial pathogens. With the aim of optimizing the use of antibiotics in food animals and minimizing the prevalence of resistant bacteria, AntibioticScout. ch provides a decision aid for the prudent use of antimicrobial drugs. This approach emphasizes the importance of supportive therapy and the hallmarks of preventive concepts. Procedures to improve animal health and animal welfare in accordance with the principles of good veterinary practice are primary and effective tools to reduce the use of antimicrobial drugs. The necessary reduction in the use of antibiotics must, therefore, be accompanied by appropriate management strategies in animal husbandry. In particular, hygiene, animal welfare and biosecurity measures are crucial to ensure an optimal health status in farm animals.

Modeling of live-birth rates and cost-effectiveness of oocyte cryopreservation for cancer patients prior to high- and low-risk gonadotoxic chemotherapy

STUDY QUESTION

What is the live-birth rate (LBR) and cost-effectiveness of fertility preservation with oocyte cryopreservation (FP-OC) compared to expectant management in cancer patients age 25-40 based on estimated gonadotoxicity of treatments 5 years after cancer diagnosis?

SUMMARY ANSWER

Oocyte cryopreservation prior to cancer treatment is more costly, yet more effective (producing more live births), than not undergoing oocyte cryopreservation but it is most beneficial for patients undergoing high-risk chemotherapy (HRC).

WHAT IS KNOWN ALREADY

The decision to undergo FP prior to treatment is multifactorial and can be costly and delay treatment. Not all treatments carry the same gonadotoxicity and patients may choose to undergo FP-OC based on the probability of premature ovarian insufficiency, predicted outcomes and cost. A comprehensive model that incorporates age at diagnosis and toxicity of treatment to help guide patients in the decision to undergo FP-OC does not yet exist.

STUDY DESIGN, SIZE DURATION

This study used a Decision Analysis Model to estimate effectiveness and cost of FP for cancer patients.

PARTICIPANTS/MATERIALS, SETTING, METHODS

Age-based estimates of LBR and cost per live birth were calculated for ages 25-40 years based on gonadotoxicity of treatment. A decision analysis model was constructed using Treeage Pro 2015 with case base probabilities derived from national registries, practice guidelines and medical records from a national network of infertility practices (IntegraMed).

MAIN RESULTS AND THE ROLE OF CHANCE

Compared to no FP-OC, FP-OC improved LBRs for women of all ages undergoing either low-risk chemotherapy (LRC) or HRC; however, it was most cost effective for women undergoing LRC at older ages or HRC at younger ages. Although FP-OC results in higher LBRs, it was always more costly. Using donor oocyte IVF can be a successful alternative to autologous FP-OC.

LIMITATIONS REASONS FOR CAUTION

Decision tree results reflect probabilities of certain events and are compiled from multiple reputable sources but are not directly derived from a recruited cohort of patients. Outcomes are based on United States estimates and should be interpreted in the broader context of individual patient diagnoses, treatment care plans and country of origin.

WIDER IMPLICATIONS OF THE FINDINGS

The development of this analytic model will help guide practitioners in their counseling of women from age 25 to 40 years, who are considering FP-OC at the time of cancer diagnosis. It provides a realistic pathway from diagnosis to LB and accounts for the majority of costs and outcome possibilities.

STUDY FUNDING/COMPETING INTEREST(s)

This study was partially funded by a grant from National Institute of Health (NIH)/National Institute of Child Health and Human Development (NICHD) (R01 HD67683) to A.Z.S. There are no conflicts of interest to declare.

TRIAL REGISTRATION NUMBER

N/A.

Wairakite, the calcium analogue of analcime, a new zeolite mineral

During the study of hydrothermal alteration of cores recovered Dfrom holes drilled at Wairakei during the exploration for geothermal steam, an unusual zeolite mineral was found. Optical, chemical, and X-ray data indicate that this zeolite is a new mineral, the calcium analogue of analcime. The name wairakite is given to the new mineral after the locality Wairakei in New Zealand. Wairakei is situated in the central part of the North Island, approximately 4 miles north-north-east from Lake Taupo, in an active volcanic region. The material was submitted to Dr. D. S. Coombs, Department of Geology, University of Otago, Dunedin, for an investigation of its X-ray crystallography.

Performance of a composite flow moulded carbon fibre reinforced osteosynthesis plate

Non-metallic implants have the advantage over metallic implants of reduction in artefact with CT and MR diagnostic imaging. In-vivo performance of a carbon fibre reinforced polyetheretherketone radiolucent plate (Snake Plate [SP]) with high stiffness, and fixed angle converging screws was compared with a seven-hole titanium Locking Compression Plate (LCP), using a sheep tibial osteotomy model (gap 0.6 mm). The sheep were divided into two groups, and the osteotomies were stabilized with a SP (n=6) or a LCP (n=6). The callus dimensions were measured radiographically at zero, two, four, six and eight weeks. The animals were euthanatized after eight weeks. Osteotomised and contralateral tibiae were tested in pairs torsion, to determine strength and stiffness. In the radii of six separate sheep, initial vascular disturbance after plate implantation was evaluated. All of the sheep of the SP and LCP groups showed maximal callus areas at six weeks. The differences between the groups, in callus dimension, were not significant at any time point. The median values for relative reduction (100 x [operated – contralateral] / contralateral) in strength of osteotomized tibiae was ™13.93% for the SP group and ™7.49% for the LCP group (p = 0.5228), and for stiffness it was ™24.44 % for the SP group and ™27.08% for the LCP group (p = 0.6481). Neither the SP nor LCP caused any notable disturbance in periosteal circulation. The SP appears to represent a valuable alternative to metallic implants for shaft fracture repair. The main advantages of the SP are radiolucency, high deformation resistance, internal fixator concept and converging screw configuration for optimal loading conditions in the bone-implant construct.

Collateral Ligament Prosthesis for Stabilization of Transverse Subchondral Fracture of Metatarsus III/IV in a Calf

The successful use of a collateral ligament prosthesis for stabilization of a transverse subchondral fracture of metatarsus III/IV in a newborn calf is reported. The proximal metaphysis of the right metatarsus III/IV was displaced medially with the medial collateral ligaments ruptured. On the medial side the periosteum was intact, whereas it was detached on the lateral side. The fracture was reduced and the collateral ligaments and the periosteum were reattached on the lateral side of the proximal metatarsus III/IV using titanium alloy staples. On the medial side a braided polypropylene yarn prosthesis, including the ruptured collateral ligaments was attached to the os tarsale II/III and the proximal metatarsus III/IV, using titanium alloy staples. The minimal internal stabilization was reinforced by a full limb fibreglass cast.

Seven months after the operation clinical and radiographic follow-up examination revealed complete healing of the fracture without signs of ankylosis of the tarsometatarsal joint. The calf did not show any signs of lameness and axial alignment of the fractured bone in the frontal and sagittal plane was excellent.

Subchondral fractures in calves have rarely been described. The case reported here deals with treatment of a subchondral fracture of metatarsus III/IV in a newborn calf. Open fracture reduction was followed by minimal internal stabilization, using a collateral ligament prosthesis, which was reinforced by external coaptation. Follow-up examination revealed complete healing of the fracture in good alignment.

Treatment of Delayed Union and Septic Osteomyelitis of Metacarpus III/IV in a Calf Using Gentamicin-impregnated Collagen Sponges and Minimal External Coaptation

A newborn calf was admitted for evaluation of a primarily closed comminuted metaphyseal fracture of metacarpus III/IV. Closed reduction and application of transfixation pins and a fibreglass cast were performed. Ten days after pin removal, radiographs revealed that the initially healed fracture had collapsed, and osteomyelitis was diagnosed. Bacteriological culture from the deep draining tract yielded Actinomyces pyogenes and Staphylococcus aureus. Standard treatment of delayed union or nonunion caused by septic osteomyelitis consists of surgical debridement, rigid fixation, and long-time administration of antibiotics. In this case, we used surgical debridement, administration of a new long-acting local antibiotic (gentamicin- impregnated collagen sponges), and minimal external stabilization. At day 27 after initiation of this treatment, the skin defect had healed, and the fracture was stable on manual palpation.

Standard treatment of delayed union or nonunion caused by septic osteomyelitis consists of surgical debridement, rigid fixation and prolonged administration of antibiotics. In the case described, we used surgical debridement, administration of a long-acting local antibiotic (gentamicin-impregnated collagen sponges), and minimal external stabilization. The promising outcome of this case and the good results in human surgery warrant further investigation in the use of gentamicin-impregnated collagen sponges in veterinary orthopaedics.

Shaft Fractures of the Metacarpus and Metatarsus in Cattle

This study describes the history, signalment, fracture configuration, methods of treatment and outcome of 58 cattle suffering from a shaft fracture of the metacarpus or metatarsus. For the purpose of describing the accuracy of fracture reduction and progress of healing, as defined by radiographs, a grading system was developed and is described.

Of the 58 animals, 17 (29.3%) were treated by means of a full-limb cast, seven (12.1%) by a walking-cast, 13 (22.4%) by a modified walking-cast, and 11 (19.0%) by open reduction and internal fixation (ORIF). Ten animals (17.2%) were slaughtered, because of economic reasons, immediately after the diagnosis had been confirmed. The (modified) walking-cast techniques were more frequently used for treatment of complex fractures; full-limb cast and ORIF were more frequently used for the other fracture types. Radiographic long-term followup data revealed that ORIF provided significantly better long-term results than external coaptation. An angular limb deformity in the saggital plane (plantar bowing) occurred in three of four metatarsal, but not in metacarpal fractures treated by external coaptation. A significant correlation existed between the quality of fracture reduction and the long-term result. However, a correlation was not found between the age and body weight of the animals and the outcome, and between the time from trauma to treatment and the outcome.

Fifty-eight shaft fractures of the metacarpus and metatarsus in cattle were evaluated retrospectively using a new radiographic scoring system. Open reduction and internal fixation provided significantly better long-term results than external coaptation. A significant correlation was found between the quality of the fracture reduction and the long-term result; a correlation was not found between age and body weight of the animal and the outcome, nor between the time that elapsed from trauma to treatment and the outcome.

Physeal Fractures of the Metacarpus and Metatarsus in Cattle

This study describes the history, signalment, fracture configuration (classified according to Salter and Harris = SH), methods of treatment and outcome of 16 cattle suffering from a physeal fracture of the metacarpus or metatarsus. For the purpose of describing the accuracy of fracture reduction and progress of healing, as defined by radiographs, a grading system was developed and is described.

Thirteen animals (five SH I and eight SH II) were treated by means of a full-limb cast, one by a modified walking-cast (SH III) and two by open reduction and internal fixation (ORIF) (one open SH II and one SH III). Long-term follow-up evaluation revealed limb angulation, or shortening of the affected bone in seven animals (44%). Two or more signs of a fracture disease were found in 11 out of 13 cases (85%) treated by means of a full-limb cast. The long-term result of the SH III fracture treated by means of a modified walking-cast was satisfactory. A significant negative correlation was found between the body weight of the animals and the time that elapsed from trauma to treatment respectively, and the long-term result. However, correlation was not found between the quality of fracture reduction and the long-term result.

Sixteen physeal fractures of the metacarpus and metatarsus in cattle were evaluated retrospectively using a new radiographic scoring system. A significant negative correlation was found between the body weight of the animals and the time that elapsed from trauma to treatment respectively, and the longterm result. A correlation was not found between the quality of the fracture reduction and the long-term result.

Arthroscopic Lavage and Implantation of Gentamicin-impregnated Collagen Sponges for Treatment of Chronic Septic Arthritis in Cattle

The object of this retrospective clinical study was to evaluate the efficacy of arthroscopic lavage and debridement, followed by intra-articular implantation of resorbable gentamicin-impregnated collagen sponges (GICS) for treatment of chronic (≥ seven days) septic arthritis in cattle. Fourteen cattle suffering from chronic septic monarthritis refractory to previous treatment were included in this study. Age ranged from one month to 7 years (mean = 34 months) and bodyweight from 58 to 640 kg (mean = 422 kg). The degree of lameness and characteristics of synovial fluid were evaluated before and at days #10 and 20 after the initial operation. The standard surgical procedure consisted of arthroscopic “through-and-through” lavage of the affected joint with a physiological Ringer’s solution, partial synovectomy, and curettage of the articular cartilage when considered necessary, followed by the intra-articular administration of GICS. The aftercare included administration of procaine penicillin, phenylbutazone, and stall confinement. The progress of the cases was monitored at three to 24 months after the initial operation.

The tarsocrural joint was affected in six cases, the antebrachiocarpal joint in five and the metacarpophalangeal joint in three cases. The degree of lameness, total nucleated cell count and total protein of synovial fluid significantly (P <.05) decreased within 10 days after the operation. Treatment was successful in 12 of 14 animals (86%). It was therefore concluded that the implantation of GICS after routine “throughand- through” lavage is a valuable alternative technique for the treatment of chronic septic arthritis in cattle. A subsequent second operation for implant removal was not necessary, as GICS are fully absorbable. The tarsocrural joint is associated with the least favourable prognosis of the joints treated in this study.

The efficacy of arthroscopic “through-and-through” lavage and debridement, followed by intra-articular implantation of absorbable gentamicin-impreg-nated collagen sponges (GICS) for treatment of chronic (≥ seven days) septic arthritis in cattle was evaluated. Treatment was successful in 12 of 14 cattle (86%). This suggests that the described technique is a valuable alternative to established treatment regimens for prolonged intra-articular administration of gentamicin. When compared to gentamicin-impregnated polymethylmethacrylate beads, GICS have the advantage that a second operation for implant removal is not necessary.

Internal Fixation of Long Bone Fractures in Farm Animals

This study demonstrates that long bone fracture treatment in food and fibre producing animals is in most cases successful. The greatest disadvantage of such treatment are the costs of the surgery and implants.

A genome-wide significant association on chromosome 2 for footrot resistance/susceptibility in Swiss White Alpine sheep

Footrot is one of the most important causes of lameness in global sheep populations and is characterized by a bacterial infection of the interdigital skin. As a multifactorial disease, its clinical representation depends not only on pathogen factors and environmental components but also on the individual resistance/susceptibility of the host. A genetic component has been shown in previous studies; however, so far no causative genetic variant influencing the risk of developing footrot has been identified. In this study, we genotyped 373 Swiss White Alpine sheep, using the ovine high-density 600k SNP chip, in order to run a DNA-based comparison of individuals with known clinical footrot status. We performed a case-control genome-wide association study, which revealed a genome-wide significant association for SNP rs418747104 on ovine chromosome 2 at 81.2 Mb. The three best associated SNP markers were located at the MPDZ gene, which codes for the multiple PDZ domain crumbs cell polarity complex component protein, also known as multi-PDZ domain protein 1 (MUPP1). This protein is possibly involved in maintaining the barrier function and integrity of tight junctions. Therefore, we speculate that individuals carrying MPDZ variants may differ in their footrot resistance/susceptibility due to modified horn and interdigital skin integrity. In conclusion, our study reveals that MPDZ might represent a functional candidate gene, and further research is needed to explore its role in footrot affected sheep.

[Open digit amputation in cattle: Surgery, wound healing and follow-up]

INTRODUCTION

The aim of this retrospective study was to document secondary wound healing and outcome in 20 cattle that had undergone digit amputation at the level of the distal metaphysis of the first phalanx between April 2009 and June 2015. The surgical technique for amputation was simple and fast, and granulation tissue covered the stump of the first phalanx 9 to 30 days postoperatively. Complications associated with wound healing were seen in 7 animals and in 3, a second surgery was required; all 20 cattle were discharged from the clinic. Epithelial closure was complete after a mean of 3 months (range, 2 to 7 months). The mean postoperative survival time was 15 months (range, 1 to 34 months), and 6 animals were still alive at the time of follow-up inquiry. Wound healing and long-term outcome did not differ between cattle that had undergone a more intensive aftercare regime than those with a less intensive postoperative treatment.

Evaluation of arterial digital blood flow using Doppler ultrasonography in healthy dairy cows

BACKGROUND

Local circulatory disturbances have been implicated in the development of foot disorders in cattle. The goals of this study were to evaluate the suitability of the interdigital artery in the pastern region in both hind limbs using pulsed-wave (PW) Doppler ultrasonography and to investigate quantitative arterial blood flow variables at that site in dairy cows. An Esaote MyLabOne ultrasound machine with a 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the pastern region in both hind limbs of 22 healthy German Holstein cows. The cows originated from three commercial farms and were restrained in a standing hoof trimming chute without sedation.

RESULTS

A PW Doppler signal suitable for analysis was obtained in 17 of 22 cows. The blood flow profiles were categorised into four curve types, and the following quantitative variables were measured in three uniform cardiac cycles: vessel diameter, pulse rate, maximum systolic velocity, maximum diastolic velocity, end-diastolic velocity, reverse velocity, maximum time-averaged mean velocity, blood flow rate, resistance index and persistence index. The measurements did not differ among cows from the three farms. Maximum systolic velocity, vessel diameter and pulse rate did not differ but other variables differed significantly among blood flow profiles.

CONCLUSIONS

Differences in weight-bearing are thought to be responsible for the normal variability of blood flow profiles in healthy cows. The scanning technique used in this report for evaluation of blood flow in the interdigital artery appears suitable for further investigations in healthy and in lame cows.

Evaluation of arterial digital blood flow using Doppler ultrasonography in healthy dairy cows

BACKGROUND

Local circulatory disturbances have been implicated in the development of foot disorders in cattle. The goals of this study were to evaluate the suitability of the interdigital artery in the pastern region in both hind limbs using pulsed-wave (PW) Doppler ultrasonography and to investigate quantitative arterial blood flow variables at that site in dairy cows. An Esaote MyLabOne ultrasound machine with a 10-MHz linear transducer was used to assess blood flow in the interdigital artery in the pastern region in both hind limbs of 22 healthy German Holstein cows. The cows originated from three commercial farms and were restrained in a standing hoof trimming chute without sedation.

RESULTS

A PW Doppler signal suitable for analysis was obtained in 17 of 22 cows. The blood flow profiles were categorised into four curve types, and the following quantitative variables were measured in three uniform cardiac cycles: vessel diameter, pulse rate, maximum systolic velocity, maximum diastolic velocity, end-diastolic velocity, reverse velocity, maximum time-averaged mean velocity, blood flow rate, resistance index and persistence index. The measurements did not differ among cows from the three farms. Maximum systolic velocity, vessel diameter and pulse rate did not differ but other variables differed significantly among blood flow profiles.

CONCLUSIONS

Differences in weight-bearing are thought to be responsible for the normal variability of blood flow profiles in healthy cows. The scanning technique used in this report for evaluation of blood flow in the interdigital artery appears suitable for further investigations in healthy and in lame cows.