Low 25-hydroxyvitamin D concentrations in wild rabbits (Oryctolagus cuniculus) in southern Finland.

BACKGROUND: Diet and endogenous vitamin D synthesis are possible sources of vitamin D in wild rabbits. Higher 25-hydroxyvitamin D (25(OH)D) concentrations have been reported in rabbits after artificial UVB light exposure than in rabbits without this exposure, suggesting that endogenous vitamin D synthesis occurs in the former group. In Finnish pet rabbits, diet was reported as main source of vitamin D, while outdoor access was not. Finland's northern location only enables endogenous synthesis from mid-March to mid-October in people with light skin type. Living conditions during winter are challenging for Finnish wild rabbits. This study aimed to measure serum 25(OH)D concentrations and possible natural seasonal variation of vitamin D concentrations in Finnish wild rabbits. RESULTS: Post-mortem blood samples (n = 78) were collected between 2013 and 2021 from wild rabbits hunted for reduction of the wild rabbit population. Separated sera were stored at - 80 °C until 25(OH)D concentrations were measured by enzyme immunoassay. Data regarding sex were available from 50 rabbits, 29 (58%) of which were females. Mean 25(OH)D concentration was 3.3 (range 0.3-7.1) ng/ml. 25(OH)D concentration was statistically similar between season (autumn, winter, summer), month or year of sample collection, and sex. CONCLUSIONS: Wild rabbits living in Finland have very low serum 25(OH)D concentrations. This is far below the previously suggested threshold of vitamin D deficiency in rabbits (17 ng/mL) or the mean 25(OH)D concentration reported in Finnish pet rabbits (26.0 ng/mL). Seasonal variation was not observed in 25(OH)D concentrations between winter and summer months. Even though rabbits are crepuscular animals and may spend the mid-day in underground burrows, the very low observed 25(OH)D concentrations raise doubt about whether vitamin D synthesis occurs efficiently in the skin of rabbits and whether the diet of wild rabbits provides adequate amounts of vitamin D. Cutaneous vitamin D synthesis, possible long-term consequences of low 25(OH)D concentrations, and the association of low vitamin D status with other health disorders warrant further investigations in rabbits.

Serum vitamin D in sanctuary chimpanzees (Pan troglodytes) in range countries: A pilot study.

BACKGROUND: Vitamin D is essential for skeletal health, calcium homeostasis and general health. The major and more stable form of vitamin D in circulation is 25-hydroxyvitamin D (25-OH-D); this is the most valuable indicator of vitamin D status. There are studies on laboratory and zoo-housed chimpanzees; however, serum vitamin D status has not been documented in chimpanzees in range countries. OBJECTIVES: (1) Determine the range of circulating 25-OH-D concentrations in chimpanzees in range countries. (2) Assess the influence of age, sex, and sun exposure on 25-OH-D serum concentrations. METHODS: Opportunistic blood samples were obtained from 127 clinically healthy chimpanzees. Serum 25-OH-D concentration was measured with a commercially available competitive ELISA. RESULTS: The median overall 25-OH-D concentration for chimpanzees in range countries was 46.24 nmol/L (range: 17.10-109.23 nmol/L). Males had a significantly lower concentration (40.15 nmol/L) than females (49.61 nmol/L), and infants (37.99 nmol/L) had a significantly lower concentration than adults (46.04 nmol/L). Concentrations of 25-OH-D in chimpanzees in sunnier habitats were significantly higher compared to thick tropical forest habitat. CONCLUSION: The present constitutes a large dataset of serum 25-OH-D concentrations in range country sanctuary chimpanzees and contributes to document normal ranges. Age, sex, and sun exposure influenced serum concentrations of 25-OH-D in sanctuary chimpanzees.

The effects of age, sex, breed, diet, reproductive status and housing condition on the amounts of 25(OH) vitamin D in the serum of healthy dogs: Reference values.

BACKGROUND: Optimal amount of vitamin D for the proper functioning of the immune system is different from the required vitamin D amount for bones to prevent rickets. However, reports on vitamin D reference values in dogs are minimal, and there is still not enough information regarding the relationship between vitamin D and various variables such as disease, age, breed, diet type, and so on, as well as its relationship with haematological and serum biochemical parameters. OBGECTIVES: The present study aimed to determine reference values of 25(OH) Vit D in dogs and its concentration in different groups, categorized based on age, sex, breed, housing conditions, and diet, as well as 25(OH) Vit D relationship with hematology and serum biochemistry parameters. METHODS: In this study, 90 healthy dogs were selected to determine the reference value of 25 (OH) Vit D of serum after evaluating of their haematological and biochemical parameters to assess their general health. Dogs were divided into different groups according to above-mentioned variables. Serum 25 (OH) Vit D was subsequently measured by the ELISA method. RESULTS: The median concentration of 25 (OH) Vit D was 52.50 ng/ml with minimum and maximum amounts of 14.00 and 155.57 ng/ml, respectively. No significant difference was observed between 25 (OH) Vit D levels in the studied dogs regarding their different age, sex, breed, diet, housing condition, and reproductive status. Serum 25 (OH) Vit D concentration is directly correlated with the number of band neutrophils (p < 0.05). We also witnessed indirect correlations between serum 25 (OH) Vit D levels and the number of blood eosinophils and serum glucose (p < 0.05). CONCLUSION: In the present study age, sex, breed, housing condition and age had no significant effects on the amounts of 25(OH) vitamin D. According to correlations of vitamin D with MCH, band and eosinophil numbers and glucose, vitamin D may have a role in erythropoiesis and leukocytes response and also in energy metabolism in dog.

CLINICAL AND PATHOLOGIC FINDINGS OF AN OUTBREAK OF VITAMIN D3-RESPONSIVE METABOLIC BONE DISEASE IN HERON AND EGRET (FAMILY ARDEIDAE) CHICKS FED CAPELIN (MALLOTUS VILLOSUS).

An increase in cases of metabolic bone disease (MBD) in chicks of six species of heron and egret (family Ardeidae) was identified at a wildlife rehabilitation center in the spring and summer of 2018. The outbreak affected 34.3% of birds in care for four or more days during the first 3 mo of the study and was the most common reason for euthanasia during that time. Cases were characterized by lameness, increased flexibility of multiple long bones, angular deformities, and bone fractures. Gross postmortem examinations were conducted on 145 nestlings and fledglings that died or were euthanatized either because of MBD or for unrelated conditions. Histology was performed in four cases and three controls. Histologic findings were characterized by multiple lesions in the appendicular long bones, including variable elongation of the physis, retention of cartilage cores in the metaphyseal primary spongiosa, poorly mineralized osteoid seams within the primary spongiosa, thinning or lack of diaphyseal cortical bone compaction, and folding fractures typically propagating through the physis-metaphyseal interface. Folding fractures were often associated with focal metaphyseal fibroplasia. The parathyroid gland diameter of birds diagnosed postmortem with MBD in care was significantly larger than that of unaffected birds. The authors hypothesized that a dietary deficiency of vitamin D3 because of low levels in the bird's captive diet of capelin (Mallotus villosus) was the cause of the MBD. Starting in mid-July every chick's diet was supplemented with 714 IU oral vitamin D3/kg body weight per day, after which the number of birds developing MBD declined to a rate of 4.3%. This study characterizes the clinical, gross, radiographic, and histologic features of vitamin D3-responsive MBD in young herons and egrets and provides evidence to support the recommendation that captive birds on a diet of capelin be supplemented with vitamin D3, especially during growth.

Serum 25-hydroxyvitamin D concentration and infectious respiratory disease complex in shelter dogs.

BACKGROUND: Hypovitaminosis D is a risk factor for the development of respiratory infections in humans and repletion can be protective. OBJECTIVES: Determine if serum 25-hydroxyvitamin (OH)D concentrations are lower in shelter dogs and if 25(OH)D concentrations are associated with clinical signs of canine infectious respiratory disease complex (CIRDC) or with time in the shelter. ANIMALS: One hundred forty-six shelter dogs (clinically ill n = 36, apparently healthy n = 110) and 23 nonshelter control dogs. METHODS: Prospective cohort study. Shelter dogs were grouped as clinically ill or apparently healthy based on the presence or absence, respectively, of clinical signs associated with CIRDC. Serum 25(OH)D concentrations were measured with a competitive chemiluminesence immunoassay. Nucleic acids of agents associated with the CIRDC were amplified by polymerase chain reaction assays. RESULTS: The concentration of 25(OH)D was 7.3 ng/mL (4.5-9.9, 95% confidence interval [CI]) lower in dogs with signs of CIRDC than apparently healthy shelter dogs (t(142) = 2.0, P = .04). Dogs positive for DNA of canine herpesvirus (CHV)-1 had serum 25(OH)D concentrations 14.9 ng/mL (-3.7 to 29.6, 95% CI) lower than dogs that were negative (t(137) = 2.0, P = .04). Serum 25(OH)D concentrations in shelter dogs were not different from control dogs (t(45) = -1.4, P = .17). Serum 25(OH)D concentration was not associated with duration of time in the shelter (F(1, 140) = 1.7, P = .2, R2 = 0.01). CONCLUSION AND CLINICAL IMPORTANCE: Vitamin D could have a role in acute respiratory tract infections in shelter dogs.

Determinants of vitamin D status in Kenyan calves.

Vitamin D plays a critical role in calcium homeostasis and in the maintenance and development of skeletal health. Vitamin D status has increasingly been linked to non-skeletal health outcomes such as all-cause mortality, infectious diseases and reproductive outcomes in both humans and veterinary species. We have previously demonstrated a relationship between vitamin D status, assessed by the measurement of serum concentrations of the major vitamin D metabolite 25 hydroxyvitamin D (25(OH)D), and a wide range of non-skeletal health outcomes in companion and wild animals. The aims of this study were to define the host and environmental factors associated with vitamin D status in a cohort of 527 calves from Western Kenya which were part of the Infectious Disease of East African Livestock (IDEAL) cohort. A secondary aim was to explore the relationship between serum 25(OH)D concentrations measured in 7-day old calves and subsequent health outcomes over the following 12 months. A genome wide association study demonstrated that both dietary and endogenously produced vitamin D metabolites were under polygenic control in African calves. In addition, we found that neonatal vitamin D status was not predictive of the subsequent development of an infectious disease event or mortality over the 12 month follow up period.

Effects of surgery on free and total 25 hydroxyvitamin D concentrations in dogs.

BACKGROUND: It is unclear whether a low total 25(OH)D concentration is a cause or consequence of illnesses. To address this knowledge gap, studies measuring free and total 25(OH)D during the evolution and resolution of an inflammatory process are required. OBJECTIVES: Serum total and free 25(OH)D concentrations would transiently decline after cruciate surgery in dogs. ANIMALS: Seventeen client-owned dogs with a spontaneous cranial cruciate ligament rupture (CCLR). METHODS: A longitudinal cohort study involving the measurement of serum concentrations of total and free 25(OH)D, total calcium, creatinine, albumin, phosphate, C-reactive protein and plasma ionized calcium, at 1 day before and a median time of 1 and 60 days after surgical treatment of CCLR. RESULTS: Median serum concentrations of total 25(OH)D before surgery (80.3 nmoL/L [range, 43.5-137.3]) significantly declined immediately after surgery; (64.8 nmoL/L [range, 36.3-116.5] 1 day after surgery, P < .005) before increasing to become nonsignificantly different from concentrations before surgery at day 60 after surgery (median 78.0 nmoL/L [range, 24.2-115.8], P = .14). In contrast, median free 25(OH)D concentrations before surgery (7.6 pg/mL [range, 3.8-12.2]) significantly increased immediately after surgery (9.2 pg/mL [range, 5.2-15.7], P < .05) before declining to become nonsignificantly different from before surgery concentrations at day 60 after surgery (median 6.2 pg/mL [range, 4.0-15.8], P = .37). CONCLUSION AND CLINICAL IMPORTANCE: This study reveals the difficulties of assessing vitamin D status in dogs following elective surgery.

A review of vitamin D and its importance to the health of dairy cattle.

This Research Reflection short review will discuss vitamin D metabolism, its role in nutrition, disease prevention, and welfare of dairy cattle, as well as its toxicity. Vitamin D is an important fat-soluble vitamin. However, some researchers regard it as a hormone due to its function in the organism. Its role is not limited just to Ca homoeostasis and bone metabolism but is also associated with immunity. In dairy cattle it is known for preventing milk fever. Cows can acquire vitamin D in many ways for example through feed, parenteral injections or through UVB irradiation from the sun or artificial lighting. The vitamin D in feed can either be plant-/ fungi- based ergocalciferol or animal-based cholecalciferol. There is currently only one registered feed vitamin D supplement for cattle in the European Union and it is cholecalciferol. Animals can also synthesize their own vitamin D when 7-dihydrocholesterol in the skin is irradiated with UVB light resulting in cholecalciferol production. Despite its importance, many cattle are deficient in vitamin D due to inadequate supplementation or insufficient sun exposure. In a study performed at the Veterinary Faculty in Slovenia 12 high producing Holstein Friesian cows at a commercial dairy farm were blood tested for vitamin D status for three succeeding months and all but one were vitamin D insufficient in all testings. The cows were not exposed to direct sunlight and the content of vitamin D3 in feed was <400 IU/kg dry matter, which is less than half of the NRC (2001) recommendation. Deficiency can also occur due to diseases affecting the gastrointestinal tract, such as paratuberculosis, which lower the absorptive capacity of the gut. Vitamin D can be toxic if cows are over-supplemented or consume large quantities of plants like Trisetum flavescens, which contain an active form of vitamin D-calcitriol or its glycosides, that are activated by digestion in the rumen.

Association between vitamin D metabolites, vitamin D binding protein, and proteinuria in dogs.

BACKGROUND: Proteinuria has been associated with progression of renal disease and increased morbidity and mortality in dogs and people. In people, proteinuria also has been associated with hypovitaminosis D. Little is known about the relationship between vitamin D metabolism and proteinuria in dogs. OBJECTIVES: To further elucidate vitamin D status in dogs with protein-losing nephropathy (PLN) and minimal to no azotemia. We hypothesized that vitamin D metabolites would be lower in dogs with PLN compared to healthy dogs. ANIMALS: Twenty-three client-owned adult dogs with PLN and 10 healthy control dogs. METHODS: Serum 25-hydroxyvitamin D (25[OH]D), 1,25-dihydroxyvitamin D (1,25[OH]2 D), 24,25-dihydroxyvitamin D (24,25[OH]2 D), serum vitamin D binding protein (VDBP), and urine 25(OH)D concentrations were measured. RESULTS: Compared to healthy dogs, dogs with PLN had lower concentrations of all vitamin D metabolites (P < .01). Correlations (rho; 95% confidence interval [CI]) in dogs with PLN are reported. Serum 25(OH)D and 24,25(OH)2 D concentrations were positively correlated with albumin (r = 0.47; 0.07-0.74), and 24,25(OH)2 D was negatively correlated with urine protein-to-creatinine ratio (UPC; r = -0.54; -0.78 to -0.16). Urine 25(OH)D-to-creatinine ratio was negatively correlated with serum albumin concentration (r = -0.77; -0.91 to -0.50) and positively correlated with UPC (r = 0.79; 0.53-0.91). Serum VDBP concentration was positively correlated with serum albumin concentration (r = 0.53; 0.05-0.81). CONCLUSIONS AND CLINICAL IMPORTANCE: Dogs with PLN have decreased serum concentrations of vitamin D metabolites. Urine 25(OH)D-to-creatinine ratio and UPC are correlated in PLN dogs. Future studies are needed to assess additional management strategies for dogs with PLN.

The relationship between serum 25-hydroxyvitamin D and parathyroid hormone concentration in assessing vitamin D deficiency in pet rabbits.

BACKGROUND: Vitamin D deficiency and related metabolic bone diseases in pet rabbits have been intermittently debated. In human research, the parathyroid hormone concentration in relation to the 25-hydroxyvitamin D concentration is used to determine vitamin D deficiency. Thus, this study aimed to identify the breakpoint in the 25-hydroxyvitamin D concentration indicating a significant change in the parathyroid hormone concentration in 139 pet rabbits. An enzyme immunoassay kit was used for 25-hydroxyvitamin D analysis and the intact parathyroid hormone (PTH 1-84) immunoradiometric assay kit for parathyroid hormone analysis. The mid-tibial cortical bone density was measured using peripheral quantitative computed tomography. A segmented linear regression analysis was performed, with the 25-hydroxyvitamin D concentration as the independent variable, and parathyroid hormone, ionised calcium, total calcium, inorganic phosphorus concentrations and the mid-tibial cortical density as the dependent variables. RESULTS: The breakpoint for the parathyroid hormone concentration occurred at a 25(OH)D concentration of 17 ng/mL, whereas the cortical bone density breakpoint occurred at a 25-hydroxyvitamin D concentration of 19 ng/mL. No breakpoints were found for ionised calcium, total calcium or phosphorus. CONCLUSIONS: These results suggest that a serum 25-hydroxyvitamin D concentration of 17 ng/mL serves as the threshold for vitamin D deficiency in rabbits. Nearly one-third of the rabbits had a serum 25-hydroxyvitamin D concentration below this threshold. Concerns persist regarding the high prevalence of vitamin D deficiency in pet rabbits and the possible health consequences caused by a chronic vitamin D deficiency, including the risk for metabolic bone diseases.

Rickets in white-eared opossums (Didelphis albiventris) / Raquitismo em gambás-de-orelha-branca (Didelphis albiventris)

Two young opossums were necropsied and diagnosed with rickets. This study aims to describe the clinical-pathological aspects of rickets in Didelphis albiventris. Macroscopically, the opossums presented kyphosis and scoliosis, lateral deviation of the limbs in varus, locomotion difficulty, and enlargement with softening of costochondral junctions (rickety rosary). Samples of bones and joints were processed for hematoxylin and eosin staining and Masson's trichrome. Microscopically, we observed thickening of the epiphyseal plate, characterized by irregular and multifocal proliferation of serialized and hypertrophic cartilage zones, which formed circular groups of large, dysplastic chondrocytes towards the spongy zone, often surrounded by non-mineralized osteoid tissue. In the cortical bone, there were pale eosinophilic zones around the Havers channels consistent with non-mineralized osteoid. The staining of Masson's trichrome evidenced the accumulation of osteoid tissue in cortical and trabecular bones. It is possible that a mixed cause of absorption deficiency of vitamin D3 associated with an unbalanced Ca:P diet based on lactose-free milk and fruits may have triggered the disease.(AU)

Dois gambás jovens foram necropsiados e diagnosticados com raquitismo. O objetivo do trabalho é descrever os aspectos clínico-patológicos de raquitismo em Didelphis albiventris. Macroscopicamente os gambás apresentaram cifose e escoliose, desvio lateral dos membros em varus, dificuldade de locomoção e alargamento com amolecimento das junções costocondrais (rosário raquítico). Amostras dos ossos e articulações foram processadas para coloração de hematoxilina e eosina e Tricrômico de Masson. Microscopicamente havia espessamento da placa epifisária, caracterizada pela proliferação irregular e multifocal das zonas de cartilagem seriada e hipertrófica, que formavam grupos circulares de condrócitos grandes, displásicos em direção a zona esponjosa frequentemente cercados por tecido osteoide não mineralizado. No osso cortical haviam zonas eosinofílicas pálidas ao redor dos canais de Havers consistentes com osteoide não mineralizado. A coloração de Tricrômico de Masson evidenciou o acúmulo de tecido osteoide no nosso cortical e trabecular. Acredita-se que uma causa mista de déficit de absorção de vitamina D3 associada a uma dieta desbalanceada em Ca:P a base de leite sem lactose e frutas tenha desencadeado a doença.(AU)

Serum vitamin D status in sick cats with and without cholestatic liver disease.

OBJECTIVES: Vitamin D deficiency accompanies chronic cholestatic liver disease (CLD) in humans. The vitamin D status of cats with CLD is unknown. The objectives of this study were to describe serum vitamin D concentrations in cats with CLD and to determine if they correlated with indices of liver disease severity. METHODS: Thirty-six cats with CLD, defined by increases in serum bilirubin and serum alanine aminotransferase, and 23 sick cats with non-hepatobiliary diseases were prospectively enrolled. Serum 25-hydroxyvitamin D (25[OH]D), parathyroid hormone (PTH) and ionized calcium were measured. Signalment, clinical signs, comorbidities, diet history, serum bilirubin, liver enzyme activity, albumin, phosphorus, white blood cell count, prothrombin time and final hepatic cytologic/histopathologic diagnosis, when available, were recorded. RESULTS: Median serum 25(OH)D levels were similar in cats with CLD (89.5 nmol/l; range 21-112 nmol/l) and sick cats (89.0 nmol/l; range 49-115 nmol/l). Overall 12/36 (33%) cats with CLD and 4/23 (17%) sick cats had 25(OH)D levels below the lower limit of the reference interval (<65 nmol/l). Median PTH concentrations in cats with CLD were significantly higher (0.95 pmol/l; range 0-11.3 pmol/l) than in sick cats (0.70 pmol/l; range 0.5-6 pmol/l). In cats with CLD, 6/36 (17%) had high PTH levels in contrast to only 1/23 (4%) sick cats. In cats with CLD, 25(OH)D concentrations did not correlate with serum bilirubin, albumin or serum liver enzymes but were moderately negatively correlated with white blood cell count (r = - 0.402, P = 0.013). Cats with hepatic lipidosis had the highest prevalence of 25(OH)D concentrations that fell below the reference interval. CONCLUSIONS AND RELEVANCE: Many cats with CLD have serum 25(OH)D concentrations below the lower limit of the reference interval. Further study is warranted to determine the clinical relevance and whether supplementation would provide benefits.

Low vitamin D status is associated with anaemia in hospitalised cats.

BACKGROUND: The major physiological role of vitamin D has traditionally been considered to be the regulation of calcium homeostasis and maintenance of skeletal health. However, there is increasing evidence that vitamin D influences a wider range of physiological processes including erythropoiesis. Vitamin D (25-hydroxyvitamin D, 25(OH)D) deficiency concentrations have been associated with anaemia in human beings. In contrast, the relationship between vitamin D status and erythropoiesis has not been investigated in cats. METHODS: Clinical records of cats consecutively presenting between November 2013 and February 2015 were reviewed. For each cat, data including sex, age, breed, serum albumin and creatinine concentrations, and appetite scores were extracted. A multivariable linear regression model was constructed to examine the relationship between 25(OH)D concentrations and these variables. RESULTS: Cats with anaemia had significantly lower 25(OH)D concentrations (median 49.5 nmol/l, n=31) than cats with packed cell volume above the lower limit of the reference range (median 109.0 nmol/l, n=130) (P<0.001). A binary logistic regression found that red blood cell count and mean corpuscular volume were negatively correlated with serum 25(OH)D concentrations (P<0.001 and P=0.007, respectively). CONCLUSION: Vitamin D (25(OH)D) concentration is positively associated with red blood cell count and mean corpuscular volume in cats with a wide range of different illnesses.

Vitamin D metabolism in dogs and cats and its relation to diseases not associated with bone metabolism.

Due to the presence of receptors in the cells of numerous body tissues, vitamin D is associated with several physiological functions that go beyond calcium and phosphorus homoeostasis and control of bone metabolism in the body. In humans, several studies have associated lower vitamin D concentrations with numerous diseases, such as cancer, heart disease, autoimmune diseases and infectious diseases, and also with an increase in the total mortality rate of the population. Recently, this nutrient started to gain importance in veterinary medicine, and several articles have shown a correlation between low vitamin D status and diseases unrelated to bone metabolism. The present review aims to highlight the recent publications that investigated this relationship, bringing the evidence that exists so far in dogs and cats.

Seasonal and dietary effects on Vitamin D deficiencies detected in wild boar from mid-western Spain.

Vitamin D (VitD) is involved in important mammalian physiological mechanisms, such as Ca-P metabolism, bone development and immunological response. VitD deficiencies are frequently detected in domestic animals and related to various health problems (e.g., rickets, bone deformation). However, knowledge about the status of VitD in wildlife species, such as the wild boar, is scarce. The aims of this work were to explore VitD status in wild boar populations from mid-western Spain and to elucidate the influence of daylight exposure and food supplementation in levels of VitD. Serum concentration of VitD (measured as 25-hydroxivitaminD) was assessed in 276 wild boar from 27 game estates located in mid-western Spain using a commercial ELISA kit. In 19 out of 27 estates, the staff supplied a specific VitD-enriched food (2,000 UI/Kg) ad libitum throughout the year, while in the remaining estates (8), no food was supplied. Blood samples were extracted from hunted animals (198) between October and February of hunting seasons 2016/2017 and 2017/2018, and from live wild boar (78) that were captured, sampled and released (March-September of 2017). The percentage of animals with VitD deficiency (<20 ng/ml), VitD insufficiency (20-30 ng/ml) and VitD sufficiency (>30 ng/ml) was estimated, and the relationship of these levels to factors like sex, age and season was assessed using chi-square tests. Furthermore, associations between daylight exposure and supplemental food with VitD levels were explored using linear models. Of the studied wild boar population, 82.2% showed a VitD deficiency or insufficiency. VitD deficiencies were more frequent in animals sampled in winter and spring. Furthermore, levels of VitD positively correlated with daylight exposure and supplemental food intake. Ad libitum supplementation with VitD-enriched food was insufficient to prevent VitD deficiencies in wild boar from November to April, probably because food consumption is lower during this period.

Growth Hormone Secretion Patterns in German Landrace (DL) Fetuses and Piglets Compared to DL Piglets with Inherited 1,25-Dihydroxyvitamin D3 Deficiency.

The regulation of growth hormone (GH) release during prenatal development and during early postnatal life is not entirely clarified. In this study plasma GH concentrations in pigs with inherited pseudo vitamin D deficiency type I (PDDR-I), which regularly show growth retardation, were compared during ontogeny with unaffected pigs of the same breed (German Landrace, DL) as control. Plasma GH concentrations were measured in plasma of chronically catheterized fetuses (beginning on day 101 after mating or after artificial insemination) and in piglets (day 37 postpartum (p.p.)-day 42 p.p.) of both lines. A growth curve beginning at day 7 p.p. was recorded for both lines. The relative amount of GH receptor (GHR) mRNA in liver was quantified by competitive reverse transcription polymerase chain reaction in piglets at day 42 p.p. A trend for higher GH concentrations was observed in PDDR-I fetuses (p < 0.1). In PDDR-I piglets compared to DL piglets higher plasma GH values (p < 0.01), were observed despite lower body weight. The relative quantity of GHR mRNA in liver was not significantly different between the two lines. Piglets with an inherited defect of vitamin D synthesis showed higher GH concentrations. A hormonal imprinting by low 1,25(OH)2D3 could be one reason for our observations and should be analysed in detail in future.

The pathology of vitamin D deficiency in domesticated animals: An evolutionary and comparative overview.

Although vitamin D is critical to calcium/phosphorus homeostasis, bone formation and remodeling, there is evolution-based variation between species in vitamin D metabolism and susceptibility to rickets and osteomalacia. Most herbivores produce vitamin D3 in response to sunlight, but dogs and cats have generally lost the ability as carnivore diets are rich in vitamin D. Nutritional deficiencies and/or poor exposure to sunlight can induce rickets in birds, swine, cattle and sheep, but horses are less susceptible as they have evolved a calcium homeostasis that is quite different than other animals. Adaptations to specific environments also affect disease incidence: llamas/alpacas out of their natural high altitude intense solar radiation environments are highly susceptible to vitamin D deficiency. The pathology of rickets/osteomalacia is similar across species, however fibrous osteodystrophy is more common and may also be present. Rickets/osteomalacia were likely more common in animals before the advent of commercial diets, but can be difficult to definitively diagnose especially in single archeological specimens. Consideration of species susceptibility, location - especially in terms of latitude, and any available information on diet, season of occurrence, husbandry practices or descriptions of affected animals can support the diagnosis of metabolic bone disease in animals.

Dietary imbalances in a large breed puppy, leading to compression fractures, vitamin D deficiency, and suspected nutritional secondary hyperparathyroidism.

A 6-month-old intact female giant schnauzer dog fed a nutritionally unbalanced homemade diet was evaluated because of a 1-month history of lameness and difficulty walking. Abnormalities identified on ancillary tests, in conjunction with the dog's clinical improvement following diet change, suggested a diagnosis of vitamin D deficiency and nutritional secondary hyperparathyroidism. This report underlines the importance of appropriate feeding management, especially during the vulnerable growth phase.

Déséquilibres alimentaires chez un chiot de grande race causant des fractures de compression, une carence en vitamine D et de l'hyperparathyroïdisme soupçonné secondaire à la nutrition. Une chienne Schnauzer géante intacte âgée de 6 mois qui consommait une diète maison qui n'était pas équilibrée sur le plan nutritionnel a été évaluée en raison d'une anamnèse de 1 mois de boiterie et de difficultés ambulatoires. Les anomalies identifiées sur des tests ancillaires, de concert avec l'amélioration clinique du chien après le changement de diète, suggéraient un diagnostic de carence en vitamine D et d'hyperparathyroïdisme nutritionnel secondaire. Ce rapport souligne l'importance d'une gestion appropriée de l'alimentation, particulièrement durant la phase de croissance vulnérable.(Traduit par Isabelle Vallières).

Canine Leishmaniasis Progression is Associated with Vitamin D Deficiency.

The relationship between vitamin D deficiency and the risk of suffering from a plethora of health disorders, ranging from autoimmune processes to infectious diseases has been widely described. Nonetheless, the potential role of vitamin D in visceral leishmaniasis remains uncharacterized. In the Mediterranean basin, where the dog is leishmania's main peri-domestic reservoir, control measures against the canine disease have shown beneficial effects on the incidence of human leishmaniasis. In this study, we measured the vitamin D levels in serum samples from a cohort of 68 healthy and disease dogs from a highly endemic area and we have also studied the relationship of these levels with parasitological and immunological parameters. The sick dogs presented significantly lower (P < 0.001) vitamin D levels (19.6 ng/mL) than their non-infected (31.8 ng/mL) and the asymptomatic counterparts (29.6 ng/mL). In addition, vitamin D deficiency correlated with several parameters linked to leishmaniasis progression. However, there was no correlation between vitamin D levels and the Leishmania-specific cellular immune response. Moreover, both the leishmanin skin test and the IFN-γ levels displayed negative correlations with serological, parasitological and clinical signs. Further studies to determine the functional role of vitamin D on the progression and control of canine leishmaniasis are needed.

Hypovitaminosis D is associated with negative outcome in dogs with protein losing enteropathy: a retrospective study of 43 cases.

BACKGROUND: Hypovitaminosis D has previously been shown to be prevalent amongst dogs with protein losing enteropathy (PLE). The hypothesis of this study was that Low 25-hydroxyvitamin D (25(OH) D) serum concentrations could be a risk factor for negative outcome in dogs with PLE. Forty-three dogs diagnosed with PLE (2005-2014) and which serum Vitamin D serum concentrations were collected and archived at -80 Degrees C were analyzed. Post-diagnostic communication with referring veterinarians was made to determine outcome of PLE dogss: Dogs which died due to PLE within 4 months after diagnosis (negative outcome group, n = 22) and dogs alive or which died due to another disease at the end point of the study (1 year after diagnosis, good outcome group, n = 21). Serum samples taken at the time of diagnosis were analysed for ionized calcium (iCa) concentrations and serum 25(OH) D concentration. RESULTS: Clinical (CCECAI) scores, age at PLE diagnosis, and iCa concentrations were not significantly different between dog groups. A significantly greater (p < 0.001) number of PLE dogs treated with hydrolyzed or elimination diet alone showed good outcome as compared to the PLE negative outcome group. Median serum 25(OH) D concentration was significantly (p = 0.017) lower in dogs with negative outcome versus PLE dogs with good outcome. Using logistic regression analysis, 25(OH) D serum concentration was shown to be a statistically significant factor for outcome determination. Cox regression analysis yielded a hazard ratio of 0.974 (95% CI 0.949, 0.999) per each one nmol/l increase in serum 25(OH) D concentration. CONCLUSIONS: Low serum 25(OH) D concentration in PLE dogs was significantly associated with poor outcome. Further studies are required to investigate the clinical efficacy of Vitamin D (cholecalciferol) as a potential therapeutic agent for dogs with PLE.