Methodological approaches to assessing the genetic predisposition of osteochondrosis of the tarsocrural joint in the Pura Raza Española horses.

Osteochondrosis (OC) is a developmental orthopaedic disease of significant concern in numerous sport horse breeds, with significant international relevance. Using digital radiographs, we assessed the occurrence of hock (tarsocrural joint) OC in 3 048 Pura Raza Española (PRE) horses which took part in a morpho-functional test, in three specific locations in the tarsus limbs: the Distal Intermediate Ridge of the Tibia (DIRT), the lateral trochlear ridges of the talus (LTT), and the medial trochlear ridges of the talus (MTT). An incidence rate of 13.3% was found for hock OC in the analysed sample, with the highest incidence rate observed in DIRT (10.0%) and the lowest in MTT (0.2%). Estimates of genetic predisposition to hock OC were carried out using three genetic approaches: 1a) a binomial threshold model based on the presence or absence of OC, 1b) a multinomial threshold model, on a scale from 0 (absence) to 3 (maximum), and 2) a linear model. The effects considered in the models included sex, genetic origin and stud class. All the analyses were based on the Bayesian inference methodology, using the THRGIBBS3F90 software. The binomial threshold model yielded the most suitable results, with an estimated heritability for Overall hock OC of 0.71 ± 0.055 on the underlying scale (0.53 on the observed scale), ranging in different locations from 0.48 ± 0.087 (LTT) to 0.66 ± 0.063 (DIRT) on the underlying scale (0.10 and 0.38 on the observed scale, respectively). The highest significative genetic correlation was observed between Overall and DIRT (0.97) for approach 1a, and the lowest significant genetic correlation was between Overall and LTT (0.49), for approach 2. This study contributes valuable insights into the genetic predisposition towards, as well as for the potential for selective breeding against, hock OC in PRE horses, and provides a basis for future research and breeding programmes aimed at minimising the occurrence of hock OC and promoting the overall health of this breed.

Ultrasonography of the normal donkey tarsus (equus asinus).

Tarsal joint illness is a frequent source of hind limb lameness due to the complex anatomy of the region and the presence of numerous bony and soft tissue structures. Proper lameness diagnosis aims to discover the structure provoking lameness. Ultrasonography documents valuable information of soft tissues and characterizes soft tissue injuries that have heretofore been difficult to obtain either noninvasively or via radiography. The objectives of the current study were to develop and describe a standardized ultrasonographic protocol for investigation of the tarsal region in donkeys. The donkey tarsal anatomy was investigated in 5 cadavers and the tarsi of 11 healthy lameness free adult donkeys were echographically investigated. The dorsal, plantar, lateral and medial aspects of the tarsal region were substantially evaluated at four anatomical landmarks in both the longitudinal and horizontal planes using a multi-frequency 5-12 MHz linear transducer. Sonoanatomy of the extensor and flexor tarsal tendons, collateral and plantar ligaments, and synovial pouches was delineated and described. Systematic echography of the tarsal region allowed accurate localization and thorough exploration of various soft tissues of clinical interest in the donkey tarsus. Sonograms provided in this study should serve as a reference database for tarsal ultrasonography in clinical circumstances.

Pantarsal arthrodesis stabilized with circular external skeletal fixators in 8 dogs (2010-2022).

OBJECTIVE: To report the surgical technique, complications, and outcomes of 8 dogs that underwent a unilateral pantarsal arthrodesis stabilized using a circular external skeletal fixator (CESF) construct for the treatment of uni- or multilevel tarsal instability. ANIMALS: 8 dogs. CLINICAL PRESENTATION: Medical records from 2010 to 2023 from 2 small animal hospitals were retrospectively reviewed for dogs undergoing pantarsal arthrodeses stabilized with CESF. Data collected for each dog included signalment, injury etiology, construct configuration, radiographic imaging, antimicrobial use, complications, length of time until construct removal, and outcome based on clinical evaluation by the owner and veterinary surgeon. RESULTS: 8 dogs met the requirements of inclusion for the study. Dogs had a mean age of 5.5 years (range, 0.42 to 13 years) and weight of 15.1 kg (range, 2.5 to 26.4 kg). Angulated 3- and 4-ring constructs were used in 5 and 3 dogs, respectively, with or without hybridization. Tarsi were stabilized with a mean angle of extension of 124.8° (range, 111.5° to 136.5°). Fixator removal was performed at a mean time of 11.3 weeks (range, 6 to 16 weeks). Complications developed in 4 dogs, 2 of which had poor clinical outcomes despite additional interventions, including recurrent digit trauma and poor limb use postoperatively. Six dogs had excellent outcomes. CLINICAL RELEVANCE: A CESF may be considered as an alternative to plate stabilization when performing a pantarsal arthrodesis. This fixation requires rigorous postoperative care but obviates the need for supplemental postoperative coaptation.

Fast- and slower-growing broilers respond similarly to a reduction in stocking density with regard to gait, hock burn, skin lesions, cleanliness, and performance.

There is an increasing trend toward broiler production systems with higher welfare requirements. Breed and stocking density are considered key factors for broiler welfare that are often specified as criteria for such higher welfare systems. However, it remains unknown how slower-growing broilers respond to a reduction in stocking density with regard to their welfare and performance, and whether this response differs from fast-growing broilers. Therefore, we compared fast- (F) and slower-growing broilers (S) housed at 4 different stocking densities (24, 30, 36, and 42 kg/m2, based on slaughter weight) and measured their welfare scores (i.e., gait, footpad dermatitis, hock burn, skin lesions and cleanliness), litter quality and performance. The experiment had a 2 × 4 factorial design with 4 replicates (pens) per treatment (32 pens in total). Thinning (15%) was done in a 50/50 male/female ratio at 38 (F) and 44 (S) d of age (estimated body weight of 2.2 kg). We hypothesized that breeds would respond differently to a reduction in stocking density. Contrary to our hypothesis, only one interaction between breed and stocking density was found on footpad dermatitis, indicating that fast- and slower-growing broilers generally showed similar responses to a reduction in stocking density. F broilers showed a steeper decline in the prevalence of footpad dermatitis with reducing stocking density compared to S broilers. Broilers housed at lower stocking densities (24 and/or 30 kg/m2) showed improved welfare measures, litter quality and performance compared to those housed at higher stocking densities (36 and/or 42 kg/m2). S broilers had better welfare scores (gait, footpad dermatitis and skin lesions), litter quality and lower performance compared to F broilers. In conclusion, reducing stocking density improved welfare of both F and S broilers, but more for F broilers in case of footpad dermatitis, and using S broilers improved welfare compared to F broilers. Reducing stocking density and using slower-growing broilers benefits broiler welfare, where combining both would further improve broiler welfare.

Effect of silvopasture system on fearfulness and leg health in fast-growing broiler chickens.

A silvopasture system intentionally integrates trees, forages, and livestock, allowing dual land use. These systems can provide high-quality habitat for broiler chickens; however, such systems have not been widely adopted by the broiler industry in the United States. The objective of this study was to examine the effect of silvopasture versus open pasture access on fearfulness and leg health in fast-growing broiler chickens. A total of 886 mixed-sex Ross 708 chicks in Experiment 1 (Exp 1) and 648 chicks in Experiment 2 (Exp 2) were housed in coops and had access to 16 (Exp 1) or 12 (Exp 2) 125m2 silvopasture plots (x̄ = 32% canopy cover) or open pasture plots (no canopy cover) from day 24 of age. Fearfulness was measured using a tonic immobility test (tonic immobility duration), and leg health was assessed by quantifying footpad dermatitis, hock burns, gait, and performing a latency-to-lie test on days 37-39 of age. Birds in the silvopasture treatment were less fearful than birds in the open pasture treatment. Overall, birds in both silvopasture and open pasture systems had excellent leg health. Silvopasture birds had lower footpad dermatitis scores than open pasture birds. Silvopasture birds tended to have worse gait than open pasture birds in Exp 1, but not in Exp 2. Hock burn scores and latency-to-lie did not differ between treatments in Exp 1 or Exp 2. Raising birds in silvopasture reduced fear and improved footpad health compared to birds raised in open pastures, which indicates that silvopasture systems provide some benefits for affective state and leg health in fast-growing broilers.

Validation of an automatic scoring system for the assessment of hock burn in broiler.

This study aimed to develop and validate a camera vision score that could detect macroscopic alterations of the hock, to identify errors and to assess possible factors that could influence the assessment. Two hundred hocks in the first (calibration) phase and 500 hocks in the second (validation) phase were collected at slaughter, visually assessed, placed back into the evisceration line and assessed by a camera system with 2 software systems. The size of the alteration in percent (%) measured by the camera system was evaluated ("camera score", CS). Additionally, temperature, humidity, and light intensities were measured. In the calibration phase, threshold values of camera scores for respective macro scores were defined and performance measures evaluated. In the validation phase, the generated threshold values were validated, occurring errors, as well as possible impacts of climatic factors analyzed. The results showed that the generated thresholds predict the camera score values at which the respective macro score has the highest probability of appearance. Small hock burn lesions ≤0.5 cm have the highest probability at a camera score of ≥0.2 (original CS) or ≥0.1 (updated CS), and lesions >0.5 cm have the highest probability at a camera score of ≥0.7 (original CS) or ≥1.1 (updated CS). Large lesions (>0.5 cm) are more reliably identified by the system than small lesions. The risks of errors in assessing reference areas and lesions showed a correct identification of lesions to be the most probable result even if the reference area is not correctly identified. The probability of a correct identification of lesions by the camera system was slightly higher (not significant) with the updated software (risk = 0.66 [0.62-0.70]) than with the original software (risk = 0.63 [0.58-0.67]). Automatic assessment systems at slaughter could be adjusted to the presented threshold values to classify hock burn lesions. Software adaptations can improve the performance measures of diagnosis and reduce the probability of errors.

Differences and variation in welfare performance of broiler flocks in three production systems.

There is a trend toward broiler production systems with higher welfare requirements, that use slower growing broiler strains, apply a reduced stocking density and provide environmental enrichment. Although these separate factors each contribute to increased broiler welfare, there is little information on their combined effect on broiler welfare under commercial conditions, and on the variation in welfare performance of flocks within production systems. The aim of this study was to compare the welfare performance and the between-flock variation in welfare of 3 Dutch commercial broiler production systems differing in welfare requirements: Conventional (C), Dutch Retail Broiler (DRB) and Better Life one star (BLS). We applied a welfare assessment method based on the Welfare Quality broiler assessment protocol, in which we used 5 animal-based welfare measures collected by slaughterhouses and hatcheries (mortality, footpad dermatitis, hock burn, breast irritation, scratches), and 3 resource- or management-based measures (stocking density, early feeding, environmental enrichment). Data were collected for at least 1889 flocks per production system over a 2-year period. To compare the different measures and to generate an overall flock welfare score, we calculated a score on a scale from 0 to 100 (bad-good) for each measure based on expert opinion. The overall flock score was the sum of the scores of the different welfare measures. The results showed that with increasing welfare requirements, a higher total welfare score was found across production systems (BLS > DRB > C; P < 0.0001). Regarding individual measures, C generally had lower (worse) scores than BLS and DRB (P < 0.05), except for scratches where C had highest (best) score (P < 0.001). Both welfare measure scores and the total welfare score of flocks showed large variation within and overlap between systems, and the latter especially when only the animal-based measures were included in the total flock score. Total flock score ranges including animal-based measures only were: 112.1 to 488.3 for C, 113.0 to 486.9 for DRB, 151.3 to 490.0 for BLS (on a scale from 0 [bad]-500 [good]), with median values of 330.8 for C, 370.9 for DRB, and 396.1 for BLS respectively. This indicates that factors such as farm management and day-old chick quality can have a major effect on the welfare performance of a flock and that there is room for welfare improvement in all production systems.

Effect of rubber and concrete flooring on resting behavior, hock injuries, and milk production of primiparous Friesian crossbred dairy cows housed in a free-stall barn in Mid-Country, Sri Lanka.

The floor surface of the cubicle is a detrimental factor on cow comfort. The effects of two floor types, rubber and concrete, on dairy cow comfort and milk production were compared for a period of 13 weeks. Fourteen Friesian crossbred dairy cows with an average body weight of 425.67 ± 61.12 kg (mean ± SD), nose to tail body length of 2.07 ± 0.15 m, rump height of 1.29 ± 0.02 m, hook bone width of 0.48 ± 0.05 m, and body condition score (BCS) of 4.13 ± 0.44 were used, with seven cows per flooring treatment. The cows produced a mean of 15.93 ± 4.03 l/cow/day and a constant feeding plan was practiced. The swelling and wound severity of hocks diminished (P < 0.05) starting at the third and tenth weeks, respectively. Daily lying time/h (concrete: 9.67 ± 1.24, rubber: 10.60 ± 0.69, P = 0.046) and average duration of lying bouts/min increased (concrete: 58.16 ± 7.74, rubber: 65.66 ± 9.85, P = 0.050) starting from the twelfth week on rubber bedding. Prevalence of mastitis, lameness, and cow cleanliness remained unchanged on floor treatments. A progressive increase in daily milk production/l (concrete: 13.37 ± 1.46, rubber: 16.67 ± 2.24, P = 0.007) of cows in rubber bedding was observed at the fourth week of the experiment. Hence, the current study suggests that the use of softer bedding such as rubber mats could improve cow comfort and daily milk production of cows.

Polydatin Prevents Calcium Pyrophosphate Crystal-Induced Arthritis in Mice.

BACKGROUND: Polydatin is a stilbenoid with important antioxidant, anti-inflammatory, and immunomodulating properties. The aim of this study was to assess the anti-inflammatory preventive effect of polydatin in the mouse model of acute arthritis induced by calcium pyrophosphate (CPP) crystals. METHODS: Acute arthritis was induced by the injection of a suspension of sterile CPP crystals into the ankle joint of Balb/c mice. Animals were randomized to receive polydatin or colchicine (the control drug) according to a prophylactic and a therapeutic protocol. The primary outcome was the variation of ankle swelling obtained after crystal injection and treatment, while histological parameters such as leukocyte infiltration, IL-1ß and CXCL1 levels and tissue expression were considered as secondary outcomes. RESULTS: Prophylactic treatment with PD significantly diminished ankle swelling after 48 h from crystal injection. Secondary outcomes such as leukocyte infiltration, necrosis, edema, and synovitis were also decreased. PD caused a reduction in circulating levels of IL-1ß and CXCL1, as well as their tissue expression. By contrast, the therapeutic administration of PD did not have any beneficial effect. CONCLUSIONS: PD can effectively prevent acute inflammatory response to crystals in the mouse model of CPP crystal-induced arthritis. These results suggest that this bioactive compound might be used in the prevention of crystal-induced acute attacks in humans.

Welfare of broiler chickens reared in two different industrial house types during the winter season in Southern Brazil.

1. The following trial compared broiler chicken welfare in closed-sided (CS) versus open-sided (OS) industrial house types during the winter season in the South of Brazil.2. Ten flocks in each house type were evaluated as follows: a) bird health: contact dermatitis on the breast and abdominal areas (CDE), bird soiling (BSO), footpad dermatitis (FPD), hock burn (HBU), lameness (LAM), fractures (FRA), bruising (BRU), scratches (SCR), dead on arrival (DOA), and diseases (DIS); b) house environmental measurements: relative humidity (RHU), temperature (TEM), air velocity (AVE), illuminance (ILL), ammonia concentration (NH3), and carbon dioxide concentration (CO2), and c) bird behaviour and affective states: bird behaviour (BBE), touch test (TTE), and qualitative behaviour assessment (QBA).3. Statistical analyses were based on regression models for CDE, BSO, FPD, HBU, LAM and generalised linear models for DOA, FRA, BRU, SCR, and DIS. The Mann-Whitney test was used for RHU, TEM, AVE, ILL, NH3, CO2, and the t-test for TTE and LMO, with a specific regression model for BBE data and Principal Component Analysis for QBA.4. According to odds ratio for worse scores for CS relative to OS, birds were less likely to have severe scores for CDE (P = 0.040 and P = 0.007), BSO (P = 0.031, P = 0.016, and P = 0.038), and HBU (P = 0.017), and had higher median values for AVE (2.3, 0.0-7.8 m s-1 vs. 0.0, 0.0-4.3 m s-1), lower NH3 concentration (9.0, 0.0-64.0 ppm vs. 12.0, 0.0-60.0 ppm) and TTE scores (98, 96-100 vs. 67, 25-100). Worse results were observed in CS houses for higher stocking density (13.8 ± 0.2 birds/m2 vs. 12.0 ± 0.2 birds/m2), RHU (74.5, 50.7-99.9% vs 72.3, 47.4-99.9%), and TEM (23.9, 14.6-29.2°C vs. 21.7, 12.9-30.1°C), lower ILL (16.0, 1.0-60.0 lx vs. 161.0, 8.0-2380.0 lx), less drinking (P = 0.007), more inactive behaviour (P < 0.001) and lower positive emotions, according to QBA (P = 0.028).5. In the studied region and season, CS houses seemed to offer fewer welfare problems in terms of the health indicators; however, OS houses showed fewer behavioural restrictions and higher positive emotional states.

Magnetic resonance imaging of the normal dromedary camel tarsus.

BACKGROUND: Magnetic resonance imaging (MRI) is the most versatile and informative imaging modality for the diagnosis of locomotor injuries in many animal species; however, veterinary literature describing the MRI of the dromedary camel tarsus is lacking. Our purpose was to describe and compare the MRI images of twelve cadaveric tarsi, examined in a 1.5 Tesla MRI scanner, with their corresponding anatomical gross sections. Turbo spin-echo (TSE) T1-weighted (T1), T2-weighted (T2), proton density-weighted (PD), and short tau inversion recovery (STIR) sequences were obtained in 3 planes. Tarsi were sectioned in sagittal, dorsal, and transverse planes. MRI images from different sequences and planes were described and compared with the anatomical sections. RESULTS: The soft and osseous tissues of the dromedary camel tarsus could be clearly defined on MRI images and corresponded extensively with the gross anatomic sections. The obtained MRI images enabled comprehensive assessment of the anatomic relationships among the osseous and soft tissues of the camel tarsus. Several structure were evaluated that cannot be imaged using radiography or ultrasonography, including the transverse inter-tarsal ligaments, the talocalcaneal ligament, the short dorsal ligament, branches of the short medial and lateral collateral ligaments and the tarsometatarsal ligaments. Specific anatomical features regarding the dromedary camel tarsus were identified, including the fused second and third tarsal bone, an additional bundle of the short medial collateral ligament connecting the talus and metatarsus and the medial and lateral limbs of the long plantar ligament. CONCLUSIONS: MRI images provided a thorough evaluation of the normal dromedary camel tarsus. Information provided in the current study is expected to serve as a basis for interpretation in clinical situations.

Treatment of Rheumatoid Arthritis by Serum Albumin Nanoparticles Coated with Mannose to Target Neutrophils.

Rheumatoid arthritis (RA) is an angiogenic and chronic inflammatory disease. One of the most extensively used first-line drugs against RA is methotrexate (MTX), but it shows poor solubility, short in vivo circulation, and off-target binding, leading to strong toxicity. To overcome these shortcomings, the present study loaded MTX into nanoparticles of human serum albumin modified with mannose (MTX-M-NPs) to target the drug to neutrophils. MTX-M-NPs were prepared, and their uptake by neutrophils was studied using laser confocal microscopy and flow cytometry. A chick chorioallantoic membrane assay was used to assess their ability to inhibit angiogenesis. The pharmacokinetics and tissue distribution of MTX-M-NPs were investigated using fluorescence microscopy and high-performance liquid chromatography. Their pharmacodynamics was evaluated in a rat model with arthritis induced by collagen. Neutrophils took up MTX-M-NPs significantly better than the same nanoparticles (NPs) without mannose. MTX-M-NPs markedly suppressed angiogenesis in chick embryos, and the MTX circulation was significantly longer when it was delivered as MTX-M-NPs than as a free drug. MTX-M-NPs accumulated mainly in arthritic joints. The retention of NPs was promoted by mannose-derived coating in arthritic joints. Serum levels of inflammatory cytokines, joint swelling, and bone erosion were significantly decreased by MTX-M-NPs. In conclusion, these NPs can prolong the in vivo circulation of MTX and target it to the sites of inflammation in RA, reducing drug toxicity. MTX-M-NPs allow the drug to exert its intrinsic anti-inflammatory, antiangiogenic, and analgesic properties, making it a useful drug delivery system in RA.

Making tiestalls more comfortable: IV. Increasing stall bed length and decreasing manger wall height to heal injuries and increase lying time in dairy cows housed in deep-bedded tiestalls.

Poor stall configuration can negatively affect cow welfare by impairing lying behavior and leading to injuries in dairy cows. The comfort of the stall bed in tiestalls is affected by the material components of the stall bed (stall base and bedding), but also by the amount of space provided. The amount of space cows are able to access lengthwise in a tiestall is determined by the stall bed length and the height of the manger wall (the front limit of the stall bed), which can limit access into the space available at the front of the stall. This project aimed to maximize cow comfort in deep-bedded tiestalls by investigating the combined effect of increased bed length and decreased manger wall height in a crossover experiment (2 periods with 1 wk habituation + 6 wk data collection). Two rows of 12 tiestalls were modified (n = 24 cows). Each row was a different length, short (178 cm; length commonly found in Quebec) or long (188 cm), and cows remained on the same row (same stall bed length) for the entire experiment. In each row, there were 6 stalls of each manger wall height treatment: high (20 cm, upper limit recommended) or low (5 cm). During period 2, cows switched manger wall height treatments. A 7.6-cm-deep straw bedding layer was added to all stalls by adding a bedding keeper to the ends of stalls. All initially injured locations healed over the 14-wk study, and 2 patterns of healing emerged. Improvement in hock injury (lateral tarsal and calcanei) was observed from wk 1 to 6 for all treatments. A plateau in injury severity score reduction was observed in period 2 for the hock (lateral, dorsal, and medial calcanei), anatomical knee, carpal joints (front knees), and proximal and medial neck, which was likely the result of the insensitivity of the injury scoring scheme rather than healing not occurring. Cows in long stalls were found to spend more time lying (14.1 vs. 13.3 h/d) and had longer lying bouts than cows in short stalls (74.1 vs. 52.9 min/bout). Manger wall height did not affect injury or lying time, but may affect how cows position themselves while lying. Higher lying times in our study were comparable to those reported in deep-bedded loose pens, indicating that cows with more bedding, especially those in long stalls, were more comfortable. Our results suggest that deep-bedded straw stalls with bedding keepers have the potential to be beneficial to cow comfort on tiestall farms.

Incidence of udder cleft dermatitis (UCD) in dairy cows and risk factors for transitions to UCD.

Udder cleft dermatitis (UCD) is a common skin condition in Swedish dairy cows, affecting the anterior parts of the udder. The main objective of this study was to investigate incidence rate and duration of UCD in a 1-yr longitudinal study. Other objectives were to investigate risk factors for transitions from being healthy to having mild or severe UCD, and from having mild UCD to having severe UCD, and associations between UCD and clinical mastitis, somatic cell count (SCC) and hock lesions. Seven herds were included in the study and visited 9 times each at 6-wk intervals. At the visits, mild and severe UCD lesions, hock lesions, udder conformation traits, and hygiene scores were registered for each cow milked in the milking parlor. Information on breed, parity, days in milk (DIM), results from test milkings (milk production, SCC, and urea level), and veterinary treatments was also obtained. A UCD case was defined as one or several consecutive observations of UCD. The incidence and duration of UCD were described. Mixed-effect logistic regression models were used to analyze associations between potential risk factors and transitions to any type of UCD. Separate risk factor analyses were performed for transitions to mild and severe UCD. Associations with SCC, mastitis, and hock lesions were also analyzed with mixed-effect logistic regression models. The mean overall incidence of new UCD cases for all visits and herds was 0.5 cases per cow-year at risk. Risk factors associated with a higher risk of a transition to any type of UCD and mild UCD were breed (Swedish Red vs. Swedish Holstein), an indentation or fold at the fore udder attachment, and increasing DIM. In addition, a low milk urea level was associated with a lower risk of transition to any type of and mild UCD. Cows with previous mild UCD and high-yielding cows had increased risk for a transition to severe UCD. Cows that had an observed transition to severe UCD had an increased risk of veterinary-treated clinical mastitis within 6 wk after the UCD observation. No associations were found between UCD and SCC or hock lesions. The median observed duration of a UCD case was 12 wk, but most cases did not have an observed start or end during the study period. The observed duration of cases including severe UCD was longer than for cases involving only mild UCD. The high incidence and often long duration of UCD emphasize the need for preventive measures and treatment strategies.

Short communication: Accuracy of estimation of lameness, injury, and cleanliness prevalence by dairy farmers and veterinarians.

Lameness, injuries, and cleanliness are considered important indicators of dairy cow welfare, milk production, and milk quality. Previous research has identified that farmers globally underestimate the prevalence of these cow-based measurements, but no information on the perceptions of veterinarians is available. Because veterinarians are often perceived as the main providers of health advice on farms, the objective of the present study was to evaluate the relationship between the true prevalence of lameness, injury (hock, knee, neck), and cleanliness (udder, legs, flanks), and the estimated prevalence of these issues by farmers and their herd veterinarians. A cross-sectional study was conducted between February 2016 and July 2017. First, the farm owner and the herd veterinarian were asked to estimate the prevalence of lameness, of neck, knee and hock injuries, and of udder, leg, and flank cleanliness on the farm. The research team then visited the farm and scored all lactating cows in the herd for each measurement. Linear regression models were used to assess the relationship between the prevalence estimated by the veterinarians and the farmers, of each cow-based measurement, and the true prevalence on the farm. The 93 herds enrolled had a median of 55 milking cows and were housed in tiestall (90%) and freestall (10%) barns. Ten herd veterinarians participated and were involved with 2 to 22 enrolled farms each. A wide variation was detected in the true prevalence of the different cow-based measurements among herds (lameness: range = 19-72%, median = 36%; neck injuries: range = 0-65%, median = 14%; knee injuries: range = 0-44%, median = 12%; hock injuries: range = 0-57%, median = 25%; dirty udder: range = 0-55%, median 13%; dirty legs: range = 0-91%, median = 18%; and dirty flanks: range = 0-82%, median = 20%). For both veterinarians and farmers, the perception of each cow-based measurement prevalence increased incrementally as the herd's true prevalence increased. Overall, farmers and veterinarians underestimated cow-based measurements. Farmers and veterinarians more accurately estimated lameness prevalence in herds with higher prevalence than in herds with low prevalence, suggesting a better awareness of the issue on farms with lameness problems. Injuries were less accurately estimated in herds with higher injury prevalence compared with herds with lower prevalence, suggesting an opportunity for better knowledge transfer in this area.

Development syndromes in New World temperate and tropical songbirds.

We studied avian development in 49 to 153 species of temperate and tropical New World passerine birds to determine how growth rates, and incubation and nestling periods, varied in relation to other life-history traits. We collected growth data and generated unbiased mass and tarsus growth rate estimates (mass n = 92 species, tarsus n = 49 species), and measured incubation period (n = 151) and nestling period (n = 153), which we analyzed with respect to region, egg mass, adult mass, clutch size, parental care type, nest type, daily nest predation rate (DMR), and nest height. We investigated covariation of life-history and natural-history attributes with the four development traits after controlling for phylogeny. Species in our lowland tropical sample grew 20% (incubation period), 25% (mass growth rate), and 26% (tarsus growth rate) more slowly than in our temperate sample. Nestling period did not vary with respect to latitude, which suggests that tropical songbirds fledge in a less well-developed state than temperate species. Suboscine species typically exhibited slower embryonic and post-embryonic growth than oscine passerines regardless of their breeding region. This pattern of slow development in tropical species could reflect phylogenetic effects based on unknown physiological attributes. Time-dependent nest mortality was unrelated to nestling mass growth rate, tarsus growth rate, and incubation period, but was significantly associated with nestling period. This suggests that nest predation, the predominant cause of nest loss in songbirds, does not exert strong selection on physiologically constrained traits, such as embryonic and post-embryonic growth, among our samples of temperate and lowland tropical songbird species. Nestling period, which is evolutionarily more labile than growth rate, was significantly shorter in birds exposed to higher rates of nest loss and nesting at lower heights, among other traits. Differences in life-history variation across latitudes provide insight into how unique ecological characteristics of each region influence physiological processes of passerines, and thus, how they can shape the evolution of life histories. While development traits clearly vary with respect to latitude, trait distributions overlap broadly. Life-history and natural history associations differ for each development trait, which suggests that unique selective pressures or constraints influence the evolution of each trait.

Radiographic Recognition of Tarsal Malformation in 8- to 9-Week-Old Bernese Mountain Dogs.

INTRODUCTION: Tarsal malformation is a skeletal malformation of unknown aetiology associated with a variety of morphologic changes to the tarsal and metatarsal bones of the dog. OBJECTIVE: The aim of this study was to determine if early diagnosis and prevalence of tarsal malformation could be obtained at approximately 8 to 9 weeks of age in multiple litters of Bernese Mountain dogs. METHODS: A prospective study of 51 Bernese Mountain dog puppies were evaluated from 12 litters in northern Italy. Dorsoplantar radiographic views of the tarsus were obtained at 60 ± 5 days of age. Tarsal malformation was defined as an abnormal extension of the central tarsal bone on its medial side, or the presence of ectopic bone located medially to the central tarsal bone, talus and second metatarsal bones (proximomedial, distomedial and metatarsal ossification sites respectively). RESULTS: All puppies were found to be clinically normal. Thirty-nine of the 51 puppies showed ossification sites medial to the tarsus as defined. A metatarsal ossification was present in all dogs with either a proximo- or distomedial ossification site. No central tarsal bone extensions were observed. The remainder of the tarsometatarsal joints were normal. CLINICAL SIGNIFICANCE: Tarsal malformation can be identified in the 8- to 9-week-old Bernese Mountain dog. The clinical significance of tarsal malformation remains to be determined, either as an incidental finding or a precursor to the development of other clinically relevant and related issues in the tarsus.

Treatment of a large osseous defect in a feline tarsus using a stem cell-seeded custom implant.

The aim of this study is to describe the treatment of an infected segmental bone defect in a cat using a novel, custom-designed titanium implant seeded with adipose-derived stem cells (AdMSCs) to facilitate osseous ingrowth and preserve limb function. Large bone defects occur secondary to trauma, infection, or neoplasia and often result in amputation. We established a novel autologous AdMSC-impregnated trabecular metal spacer made using 3D printing, to bridge the distal tibia and metatarsal bones in the left pelvic limb of a cat that had previously undergone right pelvic limb amputation. Six months postoperatively, there was radiographic evidence of bone growth and implant integration. A titanium spacer seeded with AdMSCs successfully encouraged bone ingrowth in a large defect site and successfully preserved limb function. However, further studies are needed to justify the use of differentiated stem cell impregnated mesh as a framework to bridge large bone defects.

Hind limb conformation has limited influence on claw load distribution in dairy cows.

The high prevalence of claw lesions in dairy cows necessitates the investigation and hopefully elimination of factors involved in the etiology and pathogenesis of these disorders. Indirect genetic selection for specific conformation traits in feet and legs has been evaluated as a means of improving claw health but to date has not been successful. Claw disorders are commonly discussed in context with unequal claw load, and thus this study was designed to investigate the relationship between hind limb conformation and the load exerted on the respective claws. A total of 36 cows were divided into 3 groups of 12 based on the presence of parallel, straight, and cow-hocked hind limb conformation. The vertical ground reaction forces, claw prints, and mean and maximum pressures under the claws were measured in these cows before and after claw trimming. The principal characteristic of all 3 conformation traits was a significantly higher load on the lateral claws compared with the medial claws, which was least severe in cow-hocked cows. After functional foot trimming, the claws of the cows with straight conformation tended to have the most pronounced disproportion between the loads of the paired claws. Considering that a significantly higher load on the lateral claws occurred with all 3 conformations, the potential for improvement of claw health by means of indirect genetic selection for specific hind limb traits appears limited.

An overview of dropped hock syndrome cases in New Zealand cattle.

Case history: Data were collected from 47 outbreaks of dropped hock syndrome (DHS) that were reported by veterinarians in New Zealand to the Ministry for Primary Industries between October 2012 and August 2017. There were 181 affected dairy cows from 44 farms. Of those with records, all 86 were aged between 2-3 years-old, and 4/94 (4%) were Friesian, 56/94 (60%) were Jersey and 33/94 (35%) were Jersey/Friesian cross. Of the 47 outbreaks, 45 (96%) occurred during winter and 37 (79%) in the South Island.Clinical findings: Of 151 cases with records, hindlimb weakness (117 cows), shortened gait (112 cows) and dropped hocks (106 cows) were most commonly reported, with 110 cases being bilaterally affected. The level of diagnostic work-up and the data recorded by veterinarians for each outbreak were highly variable. Creatine kinase and aspartate aminotransferase activities were reported for 22 cases and were within normal ranges for cows with mild disease but increased in cows with severe disease. Concentrations of Cu in serum and liver were below normal for 13/22 and 9/10 cows, respectively, from six outbreaks. Of 41 cows with records for clinical outcomes, 12 had complete resolution, 18 had partial resolution, and 11 had no resolution.Pathological findings: Post-mortem data were available from 26 cases. Muscle necrosis and haemorrhage of the origin of the gastrocnemius muscle were the key gross findings. In 14 cows with records for muscle histopathology, myodegeneration and recent haemorrhage were observed, and connective tissue pathology was reported to predate muscular pathology in seven cases.Diagnosis: DHS appeared to be a degenerative rather than inflammatory condition primarily affecting the connective tissue of the hind limb, especially at the dense collagen interfaces of the gastrocnemius. Although no evidence of neuropathy was found, this cannot definitively be ruled out as a potential cause.Clinical relevance: A more standardised and systematic approach to investigating cases and recording case data is required to make robust inferences about the aetiology, risk factors, and treatment interventions for DHS.