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Bone morphology in the mid-diaphysis of the metacarpus in cattle and the effect of puberty and age has been well described. However, there is limited information on how age and not attaining puberty affects bone morphology in the epiphysis of the metacarpus. The metacarpus is comprised of the third and fourth metacarpal bones fused together to create a medial and lateral epiphysis. When a cow is in stance phase there is greater pressure on the medial claw; however, the effect of this difference in loading on bone has not been described. Therefore, the aim of this experiment was to describe bone morphology in the medial and lateral epiphysis of the metacarpus at the age of puberty in steers. The metacarpus was collected from beef cross dairy steers at approximately one and two years of age. The distal epiphysis of the metacarpus was scanned using peripheral quantitative computed tomography (pQCT). Measures were corrected for body weight and demonstrated a lack of bone growth cessation at one year of age. The lack of difference in bone morphology in the medial and lateral condyles of the distal metacarpus reflects the even loading distribution observed in the forelimb of cattle.

Charcot-Marie-Tooth disease (CMT) is a hereditary sensory and motor peripheral neuropathy that is one of the most common inherited neurological diseases of humans and may be caused by mutations in a number of different genes. The subtype Charcot-Marie-Tooth disease type 4H (CMT4H) is caused by homozygous mutations in the FGD4 (FYVE, RhoGEF, and PH domain-containing 4) gene. A previous genome-wide association study involving 130,783 dairy cows found 6 novel variants, one of which was a homozygous splice site mutation in the FGD4 gene. Descendants of carriers were genotyped to identify 9 homozygous Holstein Friesian calves that were raised to maturity, of which 5 were euthanized and sampled for histopathology and electron microscopy at 2 and 2.5 years of age. Three control Holstein Friesian animals were raised with the calves and euthanized at the same time points. No macroscopic lesions consistent with CMT4H were seen at necropsy. Microscopically, peripheral nerves were hypercellular due to hyperplasia of S100-positive Schwann cells, and there was onion bulb formation, axonal degeneration with demyelination, and increased thickness of the endoneurium. On electron microscopy, decreased axonal density, onion bulb formations, myelin outfoldings, and increased numbers of mitochondria were present. These changes are consistent with those described in mouse models and humans with CMT4H, making these cattle a potential large animal model for CMT.

Twelve cases of adult-onset blindness were identified in a flock of 130 polled Wiltshire sheep in New Zealand over a 3-year period. Affected sheep developed night blindness between 2 and 3 years of age, which progressed to complete blindness by 4 to 5 years of age. Fundic examination findings included progressive tapetal hyperreflectivity and attenuation of retinal blood vessels. Histologically, the retinas had a selective loss of rod photoreceptors with initial preservation of cone photoreceptors. Retinal degeneration was not accompanied by any other ocular or central nervous system abnormalities, and pedigree analysis suggested an inherited basis for the disease. Mating an affected Wiltshire ram to 2 affected Wiltshire ewes resulted in 6 progeny that all developed retinal degeneration by 2 years of age, while mating of the same affected ram to 6 unaffected ewes resulted in 8 unaffected progeny, consistent with autosomal recessive inheritance. Homozygosity mapping of 5 affected Wiltshire sheep and 1 unaffected Wiltshire sheep using an OvineSNP50 Genotyping BeadChip revealed an identical-by-descent region on chromosome 5, but none of the genes within this region were considered plausible candidate genes. Whole-genome sequencing of 2 affected sheep did not reveal any significant mutations in any of the genes associated with retinitis pigmentosa in humans or progressive retinal atrophy in dogs. Inherited progressive retinal degeneration affecting rod photoreceptors has not been previously reported in sheep, but this disease has several similarities to inherited retinal dystrophies in other species.

A North Island brown kiwi (Apteryx mantelli) with lameness and weight loss had a telangiectatic osteosarcoma. The left proximal tibiotarsus had bony lysis with multiple blood-filled spaces separated by thick fibrous septa and neoplastic mesenchymal cells producing osteoid (5-bromo-4-chloro-3'-indolyl phosphate/nitro blue tetrazolium positive on cytology). No metastases were noted on necropsy.

Outbreaks of humeral fractures in dairy cows have been reported in New Zealand for several years. Gross, histologic, and histomorphometric findings in the humerus from primiparous cows with spontaneous humeral fracture were compared to age-matched control cows. Affected cows had a complete nonarticular spiral fracture of the humerus. Histologically affected humeri had a thicker growth plate with abnormal architecture, thinner cortex with increased abnormal resorption, increased resorption in the distal humerus, decreased trabecular density, abnormal trabecular architecture, presence of growth arrest lines and woven bone formation. Histomorphometry showed reduction in bone volume, trabecular perimeter, and trabecular width. Cows grazed on fodder beet had thicker growth plates with an abnormal appearance compared with cows grazed on pasture, and cows with low/marginal liver copper concentration had more resorption cavities in the distal humerus and thinner cortical bone compared with cows with adequate liver copper concentration. Decreased trabecular density (OR = 249.5), abnormal cortical resorption (OR = 54.2), presence of woven bone formation in the proximal metaphysis (OR = 37.2), and the number of resorption cavities in the distal humerus were significantly associated with a high probability of fracture. Ribs had enlargement of the costochondral junction with fractures in different stages of healing. Histology of the ribs revealed abnormal growth plate appearance, presence of fracture lines, callus tissue, fibrosis, and microfractures. Cows with humeral fracture have osteoporosis due to decreased bone formation and increased bone resorption, likely associated with inadequate feed quality and perhaps copper deficiency leading to a reduction in bone strength and fracture.

The incidence of spontaneous humeral fractures in first-lactation dairy heifers in New Zealand has emphasised the need to understand the thoracic limb bone growth of dairy heifers. Previous research has indicated that a predisposing factor to spontaneous humeral fracture is nutrition. In addition, it has been hypothesised that liver copper concentration affects bone strength and may be a potential factor associated with humeral fracture risk. The aim of this study was to compare bone morphology in the mid-diaphysis of the metacarpus and humerus of heifers affected and unaffected by spontaneous humeral fractures, and determine the effect of copper status at death on bone morphology. The metacarpus and humerus were collected from heifers affected and unaffected by humeral fractures, and scanned using peripheral quantitative computed tomography (pQCT). The mid-diaphysis of the humerus of the affected group had reduced cortical bone mineral density and a trend for reduced cortical content and total bone content, which contributed to a reduced stress–strain index. The trend for reduced bone length in affected humeri provides additional support for the hypothesis of inhibited humeral growth. Heifers with low copper liver concentrations had reduced humerus lengths and reduced cortical bone mineral densities. These data support the hypothesis that the developmental window for humeral fracture is recent, and possibly associated with periods of inadequate nutrition.

Mammalian species carry ~100 loss-of-function variants per individual1,2, where ~1-5 of these impact essential genes and cause embryonic lethality or severe disease when homozygous3. The functions of the remainder are more difficult to resolve, although the assumption is that these variants impact fitness in less manifest ways. Here we report one of the largest sequence-resolution screens of cattle to date, targeting discovery and validation of non-additive effects in 130,725 animals. We highlight six novel recessive loci with impacts generally exceeding the largest-effect variants identified from additive genome-wide association studies, presenting analogs of human diseases and hitherto-unrecognized disorders. These loci present compelling missense (PLCD4, MTRF1 and DPF2), premature stop (MUS81) and splice-disrupting (GALNT2 and FGD4) mutations, together explaining substantial proportions of inbreeding depression. These results demonstrate that the frequency distribution of deleterious alleles segregating in selected species can afford sufficient power to directly map novel disorders, presenting selection opportunities to minimize the incidence of genetic disease.

Vitamin D requirements for most animals are expected to be fulfilled through daily exposure of the skin to solar ultraviolet B radiation. The synthesis of vitamin D

Growth rates associated with different artificial rearing systems have been thoroughly examined in many species. However, the effect of different rearing systems on bone morphology has not been described. The objective of this study was to examine differences in the bone mass and the relationship of peripheral quantitative computed tomography (pQCT) measures of bone with muscle area of ewe-reared lambs and artificially reared lambs. Lambs were opportunistically collected from a concurrent trial examining changes in ewe mammary glands during lactation. Thirteen lambs were artificially reared while the remaining nine were left on their dam. Measures of stature were taken throughout the six-week trial period. At approximately six weeks of age, the lambs were euthanized and the tibia was collected and scanned using peripheral quantitative computed tomography. Artificially reared lambs had reduced live weight gain and an altered pattern of stature growth. There was no effect of treatment on bone morphology (p > 0.05), but ewe reared lambs had a greater cortical bone content to muscle area ratio than artificially reared lambs (0.06 vs. 0.15, respectively). Differences in growth between ewe reared lambs and artificially reared lambs emphasizes the importance of adequate preweaning nutrition for livestock production systems that routinely use artificial rearing systems.

Hypoattenuating ocular lenses on CT have been described with cataract formation in humans, however published studies are currently lacking regarding this finding in veterinary patients. The purpose of this retrospective and prospective study was to describe the varying CT appearances of the ocular lens in vivo, and investigate the causes for CT density variations in a population of cats and dogs. A total of 102 canine and feline patients with CT of the head acquired at the authors' hospital between May 2011 and March 2019 were included. A bilateral hypoattenuating halo surrounding an isoattenuating to mildly hypoattenuating core was described in the ocular lens center of every cat in which a Philips brand proprietary image construction filter was used. A similar but more varied hypoattenuating region was noted in the lenses of 45.8% of dogs where the same filter was applied, as well as 43.8% of dogs with a second, similar filter. Ophthalmic examination of three live cats and one dog with hypoattenuating lenses demonstrated normal lens translucency, excluding the presence of cataract. The effect of different proprietary filters on lens appearance was also described in three fresh cadavers with normal lenses identified on ophthalmic, macroscopic, and microscopic examination. Etiology of the hypoattenuating areas within the ocular lens was not conclusively determined. Recognition that such a variant may be seen in the absence of cataract is important, in order to prevent misdiagnosis.

A neurological disease was investigated in 3 German Shepherd pups from the same litter that failed to grow normally, appeared stiff, were reluctant to move, and were deaf. They developed intermittent seizures and ataxia and had proprioceptive defects. Histopathology showed severe vacuolation of neurons, astrocytes in nervous tissue, renal tubular epithelial cells, and macrophages in nervous tissue, spleen, and liver. Vacuoles appeared empty with no storage material stained by periodic acid–Schiff (PAS) or Sudan black stains, leading to a diagnosis of a lysosomal storage disease and in particular an oligosaccharidosis. Biochemical and genomic studies showed that this was β-mannosidosis, not previously diagnosed in dogs. A c.560T>A transition in exon 4 of the MANBA gene was found, which segregated in these and other family members in a manner consistent with it being the causative mutation of an autosomal recessive disease. This mutation led to substitution of isoleucine to asparagine at position 187 of the 885 amino acid enzyme, a change expected to have functional significance.

Over the last 50 years, there have been major advances in knowledge and technology regarding genetic diseases, and the subsequent ability to control them in a cost-effective manner. This review traces these advances through research into genetic diseases of animals at Massey University (Palmerston North, NZ), and briefly discusses the disorders investigated during that time, with additional detail for disorders of major importance such as bovine α-mannosidosis, ovine ceroid-lipofuscinosis, canine mucopolysaccharidosis IIIA and feline hyperchylomicronaemia. The overall research has made a significant contribution to veterinary medicine, has provided new biological knowledge and advanced our understanding of similar disorders in human patients, including testing various specific therapies prior to human clinical trials.

The skeletal system is a common site for neoplasia in dogs and cats, and primary bone tumors may develop from any of the mesenchymal tissues present in bone. Imaging and histopathology are routinely used in the diagnosis of bone tumors, and the 2 techniques are highly complementary. While imaging may be highly suggestive of a specific diagnosis and treatment may be instituted based on this, definitive diagnosis requires histopathology of either incisional or excisional biopsies or an amputation specimen. However, there are a number of diagnostic dilemmas when the pathologist interprets bone biopsy samples, such as distinguishing reactive bone and tumor bone, fracture callus and tumor bone, different benign fibro-osseous lesions, and different types of bone sarcoma. This review outlines the characteristic radiographic and histologic changes associated with these diagnostic problems to aid in resolving them. When a holistic approach is taken to evaluation of the signalment, history, and clinical, radiologic, and microscopic features, a diagnosis may be possible. The pathologist is greatly assisted in the interpretation of bone samples by having access to imaging and should routinely request either the images or the imaging reports if they are not received from submitting veterinarians.

Simple Summary Bone strength in long bones is dependent on the strain it is exposed to via the forces from locomotion and bodyweight. The two strategies to increase bone strength (and reduce strain) are increasing either bone size or bone density. However, puberty initiates growth plate closure and, after puberty, most bone growth ceases. In many species, sex and age affect the relationship between bone strength and liveweight. The aim of this study was to examine how bone strength in two different limb bones was affected by age and sex in beef-cross-dairy cattle. The metacarpus and humerus was collected at time of slaughter and scanned using a peripheral quantitative computed tomography (pQCT) scanner to obtain measures of bone size and morphology from three cohorts of beef-cross-dairy cattle. Age, sex and live weight were also recorded. Live weight was the main predictor of bone size and strength, but age and sex influenced this relationship. This was reflected in heifers having a metacarpus that was shorter with less cross-sectional area and bone content than steers of the same liveweight and limited differences between steers and bulls of the same liveweight. At the same bone size older animals were heavier demonstrating an effect of age on bone maturity. Abstract In cattle, limited data have been reported about the relationship between live weight, bone size, and strength and how this relationship can be altered by factors such as sex and age. The aim of this study was to describe the relationship of peripheral quantitative computed tomography (pQCT)-derived parameters of bone strength and morphology with live weight, age and sex in beef-cross-dairy cattle. All animals were weighed the day before slaughter. The metacarpus and humerus were collected at slaughter and scanned at the mid-diaphysis using pQCT. Live weight was the primary explanatory variable for bone size and strength in all cohorts. However, the effect of age was significant, such that magnitude of response to liveweight was less in the 24-month-old cohort. Sex was significant within cohorts in that bulls had a shorter metacarpus than steers and heifers had a shorter metacarpus than steers at age of slaughter.

Simple Summary Traditionally, it has been thought that control of body phosphorus was secondary to the tighter control of calcium. However, over the last 20 years, an extensive system for control of body phosphorus by proteins called phosphatonins has been shown to exist. Most research on phosphatonins has been done in rat or mouse models. This paper looks at whether important proteins and phosphorus channels in the phosphatonin pathways are present in the kidneys of dogs, horses and sheep. The results showed that all of the components of the phosphatonin system are present in these species, but that there are species differences in which protein or channel is most common, and in the relationships between the proteins and channels. This research is important because the phosphatonin system is involved in the progression of chronic kidney disease in humans and animals, and differences in the systems between animal species may affect treatment of chronic kidney disease. Abstract The aim of this preliminary study was to determine the relative expression of phosphatonin pathway-related genes in normal dog, sheep and horse kidneys and to explore the relationships between the different genes. Kidneys were collected post-mortem from 10 sheep, 10 horses and 8 dogs. RNA was extracted, followed by reverse transcriptase quantitative polymerase chain reaction for fibroblast growth factor receptor 1 IIIc (FGFR1IIIC), sodium-phosphate co-transporter (NPT) 1 (SLC17A1), NPT2a (SLC34A1), NPT2c (SLC34A3), parathyroid hormone 1 receptor (PTH1R), klotho (KL), vitamin D receptor (VDR), 1a-hydroxylase (CYP27B1) and 24-hydroxylase (CYP24A1). NPT2a was highly expressed in the dog kidneys, compared with those of the horses and sheep. NPT1 had greatest expression in horses and sheep, although the three different NPTs all had relatively similar expression in sheep. There was little variability in FGFR1IIIc expression, particularly in the dogs and horses. FGFR1IIIc expression was negatively correlated with NPT genes (except NPT2a in sheep), while NPT genes were all positively correlated with each other. Unexpectedly, klotho was positively correlated with NPT genes in all three species. These results provide the basis for further research into this important regulatory system. In particular, species differences in phosphatonin gene expression should be considered when considering the pathogenesis of chronic kidney disease.

The aim of this study was to validate the combination of ovariectomy and glucocorticoid treatment in sheep as a large animal model for osteoporosis by measuring the concentration of specific biomarkers in the blood of the sheep and measuring bone loss over five months. Aged Merino ewes were randomly allocated into four groups: control, ovariectomy (OVX), and two OVX groups receiving glucocorticoids—one group once-monthly for five months (OVXG), and the other for two months followed by no treatment for three months (OVXG2). Parameters measured were biochemical markers of bone turnover, areal bone mineral density, volumetric bone mineral density, and total and trabecular bone parameters. Ovariectomy increased the concentrations of bone resorption marker C-terminal telopeptides of type 1 collagen (CTx-1) and bone turnover marker serum osteocalcin (OC) concentrations in the OVX group compared to control sheep. The combination of ovariectomy and glucocorticoid treatment increased the concentrations of CTx-1 and decreased serum OC concentrations in the OVXG group compared to OVXG2. Femur and lumbar spine bone density were lower in experimentally treated groups when compared with the control group. Total and trabecular vBMD in the proximal tibia were significantly lower in the treatment groups when compared with the control group. A significant negative correlation between femoral bone density and CTx-1 was found. The results of this study suggest that the combination of OVX and glucocorticoids induces bone loss in a short period of time in sheep., Highlights • Optimise and characterise a sheep model for osteoporosis over five months • Combining OVX and glucocorticoids induced BMD loss in sheep over five months. • Bone turnover markers resulted in a reduction of OC and increased CTx-1 markers.

Characterising copy number variants (CNV) of genes has gained popularity in human and animal studies since 2006. Several studies have revealed CNV play an important role in phenotypic diversity. However, only five papers have been published about CNV in sheep. This study detected CNV in 385 sheep belonging to different genetic groups, genotyped using Illumina OvineSNP50 BeadChips and analysed using SVS, PennCNV, and cnvPartition algorithms. In total, SVS detected 29,935 and 33,880 CNV segments by univariate and multivariate methods, respectively, that merged into 749 CNV regions (CNVR) (size range: 15.3–6,600.0 kb). PennCNV and cnvPartition algorithms found 4758 and 6676 CNV segments, that merged into 464 (size range: 16.4–2,108.8 kb) and 104 (size range: 87–12,093.7 kb) CNVR, respectively. Most of the detected CNVR were losses and only 69 CNVR were detected by all three algorithms. A total of 4635 Ensembl genes were identified in CNVR. In addition, the study revealed huge differences in CNV segments as well as CNVR among five breeds that were compared.

AIMS To determine the frequency of the FAS-ligand gene (FASLG) variant associated with feline autoimmune lymphoproliferative syndrome (FALPS) and the proportion of carriers of the variant in three British shorthair (BSH) breeding catteries in New Zealand. METHODS Buccal swabs were collected from all cats in two BSH breeding catteries from the South Island and one from the North Island of New Zealand. DNA was extracted and was tested for the presence of the FASLG variant using PCR. Cats with the FASLG variant were identified and the frequency of the FASLG variant allele calculated. Pedigree analysis was performed and inbreeding coefficients were calculated for cats with the FASLG variant. RESULTS Of 32 BSH cats successfully tested for the presence of the FASLG variant, one kitten (3%) was homozygous (FALPS-affected), and seven (22%) cats were heterozygous (carriers) for the FASLG variant allele, and 24 (75%) cats were homozygous for the wild type allele. The overall frequency of the FASLG variant allele in these 32 cats was 0.14. Cats carrying the FASLG variant were from all three breeding catteries sampled, including two catteries that had not previously reported cases of FALPS. Pedigree analysis revealed common ancestry of FALPS-affected and carrier cats within six generations, as well as frequent inbreeding, with inbreeding coefficients >0.12 for five cats with the FASLG variant. CONCLUSIONS AND CLINICAL RELEVANCE There was a high frequency of the FASLG variant allele (0.14) in this small sample of BSH cats, with 22% of healthy cats identified as carriers of the FASLG variant. For an inherited disease, lethal at a young age, in a small population in which inbreeding is common, these results are significant. To prevent future cases of disease and stop further spread of the FASLG variant allele within the BSH population in New Zealand, it is recommended that all BSH and BSH-cross cats be tested for the presence of the FASLG variant before mating. Cats identified as carriers of the variant allele should be desexed and not used for breeding. Results support the need for further investigations of the true frequency of the FASLG variant allele and occurrence of FALPS in the wider population of BSH cats in New Zealand.

Four Felis catus papillomavirus (FcaPV) types have been fully sequenced from domestic cats. Of these, FcaPV-2 and -3 are thought to cause feline viral plaques and Bowenoid in situ carcinomas. Two short sequences of DNA from a previously unreported PV type were amplified from a feline viral plaque using consensus PCR primers. DNA was then extracted from a swab of the lesion and two sets of 'outward facing' primers were designed using the short sequences to amplify the entire 7600bp genome of the novel PV. The PV was designated FcaPV-5 and contained putative coding regions that were predicted to produce five early proteins and two late ones. The ORF L1 showed over 65% similarity to that of FcaPV-3 and -4. Assignment to a genus was difficult as the PV was over 60% similar to PV types from 4 different genera. However, due to the ORF L1 similarity of FcaPV-3, -4, and -5, the shared host species of all three PVs, and the similar lesions associated with FcaPV-3 and -5, it is proposed all three PVs are classified within a new genus. FcaPV-5 is the third PV type to be associated with feline viral plaques. The plaque that contained FcaPV-5 showed unusual histological features including hyperplasia and PV-induced cell changes in sebaceous glands and deep within hair follicles. While additional study of further lesions of this type is required, it is possible that FcaPV-5 may be able to infect a broader range of cells than other PV types.

Vitamin D plays a central role in calcium homeostasis of most vertebrates, and is obtained in different species through diet, dermal synthesis, or a combination of both. The aim of this study was to determine the predominant routes of Vitamin D synthesis in three disparate species, brown kiwi (Apteryx mantelli), tuatara (Sphenodon punctatus), and New Zealand sea lions (Phocarctos hookeri). We surveyed plasma concentrations of 25-hydroxyvitamin D2 and D3, analysed environmental conditions and life history factors, and determined the ability of skin samples to synthesise Vitamin D3 on exposure to ultraviolet-B radiation. There was variation in the plasma/serum 25-hydroxyvitamin D3 concentrations between and within the species studied, with wild kiwi having the lowest concentrations and NZ sea lions the highest. Kiwi skin produced small but measurable amounts of Vitamin D3, while tuatara skin produced Vitamin D3 concentrations higher than that of kiwi. New Zealand sea lion skin produced the highest amount of Vitamin D3 and differed from the other two species in this study in that Vitamin D3 was present in skin before UV-B exposure. The results from this study show that all three species studied retained the ability to use both dietary and dermal sources of Vitamin D, although there was interspecies variation in the magnitude of dermal synthesis. Comparisons between these species show that there are differences in their Vitamin D pathways, but suggest that there are more factors contributing to these pathways than might be expected solely from life history characteristics.

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.

Aim: To determine if vitamin D3 treatment reduced the incidence of vaginal prolapse in pregnant sheep on a North Canterbury sheep breeding property.Methods: Pregnant ewes from a single farm were al...

Bone, despite its relatively inert appearance, is a tissue that is capable of adapting to its environment. Wolff’s law, first described in the 19th century, describes the ability of bone to change structure depending on the mechanical forces applied to it. The mechanostat model extended this principle and suggested that the amount of strain a bone detects depends on bone strength and the amount of muscle force applied to the bone. Experimental studies have found that low-magnitude, high-frequency mechanical loading is considered to be the most effective at increasing bone formation. The osteocyte is considered to be the master regulator of the bone response to mechanical loading. Deformation of bone matrix by mechanical loading is thought to result in interstitial fluid flow within the lacunar–canalicular system, which may activate osteocyte mechanosensors, leading to changes in osteocyte gene expression and ultimately increased bone formation and decreased bone resorption. However, repetitive strain applied to bone can result in microcracks, which may propagate and coalesce, and if not repaired predispose to catastrophic fracture. Osteocytes are a key component in this process, whereby apoptotic osteocytes in an area of microdamage promote targeted remodeling of the damaged bone. If fractures do occur, fracture repair can be divided into 2 types: primary and secondary healing. Secondary fracture repair is the most common and is a multistage process consisting of hematoma formation and acute inflammation, callus formation, and finally remodeling, whereby bone may return to its original form.

The aim of this study was to determine if serum fibroblast growth factor (FGF23) concentrations were increased in dogs with chronic kidney disease (CKD). Serum samples submitted to a commercial laboratory were collected over a 15-month period, 14 samples were from dogs with a history of polyuria/polydipsia, azotaemia and low urine specific gravity, 20 samples were from non-azotaemic dogs. Serum FGF23, parathyroid hormone, total calcium and phosphorus, urea and creatinine were measured. Mann-Whitney test was used to determine differences between non-azotaemic and CKD groups; a one-way ANOVA with Tukey pairwise comparisons was used to determine any differences between International Renal Interest Society stages; and regression models were used to determine predictors of International Renal Interest Society stage, serum phosphorus and FGF23 concentrations. The median serum FGF23 concentration of dogs with CKD was 5194.6pg/mL, which was significantly greater (P

Research on Soay Island sheep showed a positive association of serum 25(OH)D concentration and fecundity, while similar research on Scottish sheep didn’t show an association with fecundity but did show an association with weaned lamb weight. Therefore the aim of this study was to determine if serum 25-hydroxyvitamin D (25(OH)D) concentrations of ewes at mating, on a commercial sheep farm, was associated with subsequent prolificacy. On a sheep and beef farm in the North Island of New Zealand 200 mixed-age Romney ewes (Ovis aries) had weights recorded and blood was collected by jugular venepuncture in April (autumn) at mating. Pregnancy testing was conducted 12 weeks after mating, using real time ultrasound to confirm pregnancy and determine whether the dams were carrying singletons, twins or triplets. Serum 25(OH)D2 and D3 concentrations, total calcium, and phosphorus concentrations were measured in the 200 pregnant ewes. A multinomial logistic regression model was fitted to the data in order to determine significant predictors of the ultrasound scanning result. The mean serum total 25(OH)D concentrations of single, twin and triplet bearing ewes were 102.0 ± 3.4, 101.0 ± 2.4 and 83.0 ± 4.5, respectively. In a multinomial logistic regression model serum total 25(OH)D and 25(OH)D3 concentrations were also negatively correlated with ewes pregnant with triplets (P = 0.015), while weight was significantly associated with both twin and triplet bearing ewes (P The reason for the lower serum 25(OH)D concentration in sheep bearing triplets is unclear, and further research is required in order to determine the mechanisms behind this. The results suggest that an effect on ewe fecundity may only be seen when serum 25(OH)D concentrations are marginal.

Calf growth rate in relation to future milk production has been thoroughly studied, however, the observation of growth arrest lines in bones from heifers with humeral fractures has highlighted the need to understand bone growth in relation to calf growth. The aim of this study was to describe the relationship of peripheral quantitative computed tomography (pQCT)-derived measures of bone strength and morphology with gross measurements of size and growth in pre-weaning dairy calves. Liveweight, height, body length, girth and leg length were measured at one, six and twelve weeks of age. At these intervals, the mid-diaphysis of the metacarpus was also scanned in the live animal using pQCT. At six and twelve weeks old, a subset of calves were euthanised and the humerus was collected and scanned at the mid-diaphysis using pQCT. Differences in growth patterns were observed between the metacarpus and humerus over time. Weight was the best predictor for measures of periosteal circumference and stress strain index (R2 = 0.49&ndash, 0.58) in the metacarpus, and also the best predictor for measures of stress strain index at all ages in the humerus (R2 = 0.94). The strong relationship with weight and bone measures emphasises the need for adequate preweaning nutrition for future bone growth.

Klebsiella pneumoniae is a Gram-negative bacterium that can be found in the environment, as well as on mucosal surfaces of humans and animals. Here, we report the genome sequence of five K. pneumoniae isolates from substrate samples and bird feces collected in the Subantarctic Islands of New Zealand.

Klebsiella pneumoniae is a Gram-negative bacterium that may cause infection in a broad range of hosts. We report here the genome sequences of seven K. pneumoniae isolates from New Zealand sea lions.

A study was conducted to determine the circadian rhythms and trends of vitamin D metabolites including 25-hydroxyvitamin D3 , 25-hydroxyvitamin D2 , 1,25-dihydroxyvitamin D and parathyroid hormone, in addition to serum calcium, phosphorus and magnesium concentrations in horses over 48 h on the shortest and longest days of the year in 2013. Five healthy adult horses (Equus caballus) were on a constant pasture feeding regimen, and blood samples were collected from each horse every 3 h over a 48-h period, starting at 07:00 PM on day one and finishing at 07:00 PM on day three, for the measurement of calciotropic hormones and electrolytes. There was a significant difference between the serum concentration of calciotropic hormones, iCa, tCa, P and tMg between the shortest (winter) and longest (summer) days of the year in horses. Serum concentration of 25OHD3 was very low and mostly undetectable. Serum iCa, 1,25(OH)2 D and PTH concentrations clearly showed a circadian rhythm on the longest days of the year and serum tCa, P and tMg concentrations showed a diurnal pattern on the longest days (summer) of the year. None of the analytes showed any circadian rhythm on the shortest days (winter) of the year. The result of this study could have significant relevance to equine athletes travelling to international equestrian competitions and facing a huge time and seasonal differences that might affect their ability to adjust their circadian rhythms to new time zones.

Housekeeping genes (HKGs) are used as internal controls for normalising and calculating the relative expression of target genes in RT-qPCR experiments. There is no unique universal HKG and HKGs vary among organisms and tissues, so this study aimed to determine the most stably expressed HKGs in the equine kidney. The evaluated HKGs included 18S ribosomal RNA (18S), 28S ribosomal RNA (28S), ribosomal protein L32 (RPL32), β-2-microglobulin (B2M), glyceraldehyde-3-phosphate dehydrogenase (GAPDH), succinate dehydrogenase complex (SDHA), zeta polypeptide (YWHAZ), and hypoxanthine phosphoribosyltransferase 1 (HPRT1). The HKGs expression stability data were analysed with two software packages, geNorm and NormFinder. The lowest stability values for geNorm suggests that YWHAZ and HPRT1 would be most optimal (M=0.31 and 0.32, respectively). Further, these two genes had the best pairwise stability value using NormFinder (geNorm V=0.085). Therefore, these two genes were considered the most useful for RT-qPCR studies in equine kidney.

Traditionally, control of phosphorus in the body has been considered secondary to the tighter control of calcium by parathyroid hormone and vitamin D. However, over the past decade, substantial advances have been made in understanding the control of phosphorus by the so-called phosphatonin system, the lynchpin of which is fibroblast growth factor 23 (FGF23). FGF23 binds to the klotho/FGFR1c receptor complex in renal tubular epithelial cells, leading to upregulation of Na/Picotransporters and subsequent excretion of phosphorus from the body. In addition, FGF23 inhibits parathyroid hormone and the renal 1α-hydroxylase enzyme, while it stimulates 24-hydroxylase, leading to decreased 1,25-dihydroxyvitamin D3. FGF23 is intimately involved in the pathogenesis of a number of diseases, particularly the hereditary hypophosphatemic rickets group and chronic kidney disease, and is a target for the development of new treatments in human medicine. Little work has been done on FGF23 or the other phosphatonins in veterinary medicine, but increases in FGF23 are seen with chronic kidney disease in cats, and increased FGF23 expression has been found in soft tissue sarcomas in dogs.

Congenital skeletal abnormalities may be genetic, teratogenic, or nutritional in origin; distinguishing among these different causes is essential in the management of the disease but may be challenging. In some cases, teratogenic or nutritional causes of skeletal abnormalities may appear very similar to genetic causes. For example, chondrodysplasia associated with intrauterine zinc or manganese deficiency and mild forms of hereditary chondrodysplasia have very similar clinical features and histologic lesions. Therefore, historical data are essential in any attempt to distinguish genetic and acquired causes of skeletal lesions; as many animals as possible should be examined; and samples should be collected for future analysis, such as genetic testing. Acquired causes of defects often show substantial variation in presentation and may improve with time, while genetic causes frequently have a consistent presentation. If a disease is determined to be of genetic origin, a number of approaches may be used to detect mutations, each with advantages and disadvantages. These approaches include sequencing candidate genes, single-nucleotide polymorphism array with genomewide association studies, and exome or whole genome sequencing. Despite advances in technology and increased cost-effectiveness of these techniques, a good clinical history and description of the pathology and a reliable diagnosis are still key components of any investigation.

This study describes a syndrome of neonatal septicemia and meningitis in New Zealand sea lions, caused by a strain of Klebsiella pneumoniae that is phenotypically similar to strains causing environmentally-acquired septicemia and neuro-invasive disease in humans. Between late 2006 and early 2010, 123 pups from the Enderby Island breeding colony died of K. pneumoniae infection, with lesions including fibrinous to fibrinosuppurative meningitis, subdural hemorrhage, septic arthritis, herniation and hemorrhage of the cerebellar vermis, lymphadenitis and cellulitis. This infection was responsible for 58% of observed pup mortality over this time period, with most deaths occurring in the latter part of the breeding season (mid February onwards). The results of this study suggest that the pattern of this disease has changed since it was first described in 2002, when most deaths occurred early in the season (early to mid-January), and that it is an important and consistent cause of pup mortality in this population. In addition, a similar disease syndrome and bacterial strain was diagnosed in a single pup in a fragile recolonizing New Zealand sea lion population on mainland New Zealand, and the potential effect on this population is unknown but could have a negative impact on recolonisation at this site.