Tolerance evaluation of overdosed dietary levels of 25‐hydroxyvitamin D3 in growing piglets

Forty‐eight, cross‐bred (GL × LW × P) piglets were used in a 42‐day tolerance trial to assess the effects of feeding diets supplemented with vitamin D or increasing levels of 25‐hydroxyvitamin D₃ (25‐OH‐D₃). Six‐week‐old piglets (24 castrate males, 24 females) were used. Two replicate groups of 6 piglets were randomized by weight and allocated to four dietary treatments. The control group (T1) was supplemented with 50 μg vitamin D₃/kg feed. The experimental groups received 25‐OH‐D₃ at the recommended dose (T2: 50 μg/kg = 1x), at 250 μg/kg (T3: 5x) or at 500 μg/kg (T4: 10x) respectively. Feed intake and daily weight gain were measured weekly, and the animals were examined by a veterinarian daily. After 42 days, body mass, blood, urine, bone and tissue samples were analysed and a pathology examination conducted. Dietary treatments had no significant effect on final body mass or daily weight gain. The 25‐OH‐D₃ plasma concentration in T1 was 17 ± 3 ng/ml (mean ± SD) while the respective values of the experimental groups were significantly increased in T2, T3 and T4. Tissue concentrations of 25‐OH‐D₃ were higher in liver and muscle for T3 and T4 and in skin for T4 than in T1. However, neither gross pathology nor histology, nor blood and urine characteristics, nor bone parameters were affected by dietary treatments. Weight of organs as well as dry matter, ash and calcium content of kidneys remained unaffected by dietary 25‐OH‐D₃ intake. Furthermore, no changes were observed for general indicators of health. The results of this study demonstrated that feeding piglets with 25‐OH‐D₃ at 5 or 10 times the recommended level had no adverse effects on any of the biological parameters measured. It was concluded that 25‐OH‐D₃ can be regarded as a supplement with a very high safety margin when used at the recommended level.     

Survey of Zoonotic Dermatoses in Client‐Owned Exotic Pet Mammals in Southern Italy

Several ‘exotic’ mammalian species (e.g. rabbits, rodents, ferrets and hedgehogs) live in close proximity to humans as companion pets. Skin diseases (SD) are frequent causes of morbidity in exotic pet mammals, and most of those SDs have a zoonotic potential. The purpose of this study was to determine the frequencies and types of zoonotic dermatosis (ZD) in client‐owned, exotic pet mammals in Southern Italy. Six‐hundred and fifty‐five medical records of exotic pet mammals examined between 2011 and 2012, across twenty private practice veterinary clinics around the Naples area (Italy), were retrospectively evaluated and screened for animals diagnosed with SDs (rabbits n = 455, guinea pigs n = 93, ferrets n = 64, hedgehogs n = 19, chinchillas n = 13 and rats n = 11). The records of animals diagnosed with SD, whose causative agents had a zoonotic potential, were selected for analysis. The Mann–Whitney independent test was used for statistical analysis. A P value ≤0.05 was considered statistically significant. Eighty‐two records (12.5%) of animals with ZD were identified. Of those, 56.1% (46/82) were affected by fungal infections and 42.7% (35/82) by parasitic infections. No zoonotic bacterial or viral infections were diagnosed. Dermatophytosis was significantly diagnosed more frequently in younger animals. The results of this survey indicate that exotic pet mammals may serve as active carriers for many highly contagious pathogens with zoonotic potential. Awareness and vigilance by the veterinary practitioner is crucial in the prevention of occurrences of ZDs. Children frequently come in close contact with exotic pets. To prevent the unplanned transmission of pathogen from pet to human, an active routine screening examination and preventative treatments are strongly recommended for every newly purchased pet mammal.     

A comparison of UVb compact lamps in enabling cutaneous vitamin D synthesis in growing bearded dragons

The effect of exposure to different UVb compact lamps on the vitamin D status of growing bearded dragons (Pogona vitticeps) was studied. Forty‐two newly hatched bearded dragons (<24 h old) were allocated to six treatment groups (n = 7 per group). Five groups were exposed to different UVb compact lamps for two hours per day, with a control group not exposed to UVb radiation. At 120 days of age, blood samples were obtained and concentrations of 25(OH)D₃, Ca, P and uric acid were determined. In addition, plasma 25(OH)D₃ concentration was determined in free‐living adult bearded dragons to provide a reference level. Only one treatment resulted in elevated levels of 25(OH)D₃ compared to the control group (41.0 ± 12.85 vs. 2.0 ± 0.0 nmol/L). All UVb‐exposed groups had low 25(OH)D₃ plasma levels compared to earlier studies on captive bearded dragons as well as in comparison with the free‐living adult bearded dragons (409 ± 56 nmol/L). Spectral analysis indicated that all treatment lamps emitted UVb wavelengths effective for some cutaneous vitamin D synthesis. None of these lamps, under this regime, appeared to have provided a sufficient UVb dose to enable synthesis of plasma 25(OH)D₃ levels similar to those of free‐living bearded dragons in their native habitat.     

Circadian rhythm of calciotropic hormones,serum calcium,phosphorus and magnesium during the shortest and longest days of the year in horses in New Zealand

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)₂D 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.     

Anti‐Muellerian hormone concentration in bitches with histopathologically diagnosed ovarian tumours and cysts

Increased concentrations of Anti‐Muellerian hormone (AMH) can indicate a granulosa cell tumour as shown in women, mares and cows. To investigate AMH to differentiate canine granulosa cell tumour from other ovarian pathologies, we evaluated the ovaries of 63 bitches. Blood serum samples were collected before surgery for AMH analysis. Ovaries were submitted for histopathological examination. Fourteen bitches showed normal ovaries. These bitches had AMH values between 0.12 and 0.99 ng/ml. In 20 bitches ovarian cysts i.e., follicular cysts (n = 8), corpora lutea cysts (n = 7), subsurface cysts (n = 5) were diagnosed. These dogs had AMH values of 0.11–2.09 ng/ml. Bitches with small luteinized follicular cysts had slightly higher AMH values than those without ovarian alteration. In 29 cases ovarian neoplasms i.e., granulosa cell tumour (n = 9), epithelial tumours (n = 16), dysgerminomas (n = 3) and one sarcoma were identified. Anti‐Muellerian hormone values of bitches with an ovarian neoplasm except granulosa cell tumour ranged from 0.18 to 1.18 ng/ml. The AMH values of bitches with granulosa cell tumour ranged from 1.12 to ≤23 ng/ml and were significantly higher (p < .05) than in all of the other bitches. The cut‐off of 0.99 ng/ml gave a sensitivity of 100% and a specificity of 94.44% to diagnose granulosa cell tumour. In conclusion, markedly elevated AMH concentrations in bitches are indicative for a granulosa cell tumour. However, negative testing does not rule out the existence of small one. Differentiation of GCT from luteinized follicular cysts may especially be difficult.     

Food and water intake and selective feeding in rabbits on four feeding regimes

Diet plays an important role in maintaining rabbit health. Feeding an incorrect diet, particularly a low fibre diet, has been linked with digestive, dental and urinary tract disease. However, food intake and dietary requirements have been poorly studied in pet rabbits. This study assessed the effects of two commonly fed pet rabbit diets [extruded nuggets with hay (EH) and muesli with hay (MH)] alongside hay only (HO) and muesli only (MO) on food and water intake in 32 Dutch rabbits. Dry matter (DM) intake was greater in the HO group and lower in the MO group than in the EH and MH groups (p < 0.001). The portion of the diet made of hay was greater in the EH group than in the MH group (p < 0.001). Water intake was positively correlated with DM intake and was greatest in the HO group (p < 0.001). Selective feeding occurred in all rabbit groups fed muesli, whether or not hay was also available. Pellets were rejected, and grains and extrudates selected. The presence of selective feeding in all rabbits fed muesli leads to the consumption of an unbalanced diet. In addition, hay intake and water intake were lower when muesli was fed. Conclusions drawn from this study are based on general recommendations for pet rabbits, and clinical disease may have developed by feeding the study diets over a longer time period, as many diet‐related conditions typically present in older rabbits. However, the study demonstrates that the feeding of muesli diets cannot be recommended.     

Effect of feeding rice whole crop silage on growth rate,levels of vitamin A, β‐carotene,vitamin E and IGF‐1 in plasma and skeletal muscle protein degradation in Japanese black calves

This study evaluated the effects of rice whole crop silage (RWCS) on growth, plasma levels of vitamin A, β‐carotene, vitamin E and IGF‐1, and expression of genes involved in muscle protein degradation and synthesis in Japanese Black calves. Eleven calves were divided into RWCS (fed RWCS ad libitum and concentrate, n = 5) and control groups (fed hay ad libitum and concentrate, n = 6). Final body weight and dairy gain were significantly larger in the RWCS group compared with the control group. Plasma β‐carotene and vitamin E concentrations were significantly higher in the RWCS group compared with control group. Although plasma vitamin E concentration in the RWCS group significantly increased from 4 to 9 months of age, it did not increase in the control group. At 6 months of age in the RWCS group, ubiquitin B (p < 0.05) and calpain 1 (p = 0.097) mRNA expression were lower than control group, but they were not different between groups at 9 months of age. These results indicate that RWCS increases plasma β‐carotene level and promotes muscle growth because of a decrease in the rate of protein degradation, but the effect is lost with the increase in plasma vitamin E level.     

Supplementation of distiller's grains during late gestation in beef cows consuming low‐quality forage decreases uterine,but not mammary,blood flow

Positive effects have been observed in offspring from beef cows supplemented with corn dried distillers grain with solubles (DDGS) during late gestation. The hypothesis of this study was that late gestational DDGS supplementation to beef cows would increase blood flow (BF) to the gravid uterus and mammary gland thus impacting birthweight and post‐natal growth of the offspring. Experiment 1 investigated mammary gland BF in multiparous cows during late pregnancy. Beef cows were fed a control (CON1) diet of low‐quality hay (n = 5) or a supplement diet (SUP1) of low‐quality hay with DDGS [1.7 g/kg of body weight (BW); n = 6]. In Experiment 2, multiparous late pregnant beef cows were fed either a control (CON2) diet of a low‐quality hay (n = 4) or a supplement diet (SUP2) of low‐quality hay with DDGS (1.7 g/kg of BW; n = 5). Uterine and mammary gland BF were recorded every 21 days during late gestation. In Experiment 1, there were no effects of diet or day on mammary gland hemodynamics. In Experiment 2, total and ipsilateral uterine BF was less (p ≤ 0.04) in SUP2 vs. CON2 cows and similar BF to contralateral horns. Mammary gland BF was unaltered by maternal supplementation. Even when measured in two different years in two different environments, mammary gland BF remained unaltered to DDGS supplementation. Investigations on the mechanism that may impact uterine BF during late gestation remain to be known.     

Urinary excretion of advanced glycation end products in dogs and cats

The present study was conducted with privately owned dogs and cats to investigate whether a relationship exists between the dietary AGEs and the urinary excretion of AGEs, as indication of possible effective absorption of those compounds in the intestinal tract of pet carnivores. For this purpose, data were collected from both raw fed and dry processed food (DPF) fed to dogs and cats, through spot urine sampling and questionnaires. Raw pet food (RF, low in AGE diets) was fed as a primary food source to 29 dogs and DPF to 28 dogs. Cats were categorized into 3 groups, which were RF (n = 15), DPF (n = 14) and dry and wet processed pet food (DWF, n = 25). Urinary-free carboxymethyllysine (CML), carboxyethyllysine (CEL) and lysinoalanine (LAL) were analysed using ultrahigh-performance liquid chromatography (UHPLC)—mass spectrometry, and were standardized for variable urine concentration by expressing the AGE concentrations as a ratio to urine creatinine (Ucr) concentration (µg/µmol Ucr). Urinary excretion of CML, CEL and LAL in dogs fed with DPF was 2.03, 2.14 and 3 times higher compared to dogs fed with RF (p < .005). Similar to the dogs, a significant difference in CML:Ucr, CEL:Ucr and LAL:Ucr between the three diet groups was observed in cats (p-overall < 0.005, ANOVA), in which the RF fed group excreted less AGEs than the other groups. Linear regression coefficients and SE of CML:Ucr, CEL:Ucr and LAL:Ucr showed that body weight and neuter status were significantly correlated with CML and CEL excretion, but not to LAL excretion. Our results revealed a significant correlation between dietary AGEs and urinary excretion of free CML, CEL and LAL, and also showed that endogenous formation of these AGEs occurs in both dogs and cats under physiological conditions.     

Serum 25‐hydroxyvitamin D concentrations in dogs – correlation with health and cancer risk

25‐hydroxyvitamin D (25(OH)D) is important in bone health as well as many diseases including cancer. Supplementation may increase responsiveness of cancer cells to chemotherapy. Serum 25(OH)D, intact parathyroid hormone (iPTH) and canine C‐reactive protein (c‐CRP) were measured in healthy dogs and dogs with haemoabdomen. Regression analysis determined optimal 25(OH)D concentrations. In healthy dogs (n = 282), mean iPTH concentrations correlated inversely (r² = 0.88, P < 0.001) to 25(OH)D concentrations. Variation in both iPTH and c‐CRP plateaued at 25(OH)D concentrations of 100–120 ng mL^?1. Haemoabdomen dogs (n = 63, 43 malignant and 20 benign) had 25(OH)D concentrations ranging from 19.4 to >150 ng mL^?1. Relative risk of cancer increased with decreasing 25(OH)D concentrations [RR = 3.9 for 25(OH)D below 40 ng mL^?1 (P = 0.0001)]. Serum 25(OH)D concentrations in dogs vary widely, and are influenced by dietary VitD content. Serum vitD measurement can identify dogs for which supplementation may improve health and response to cancer therapy.     

Elevated cyclin D1 expression is governed by plasma IGF‐1 through Ras/Raf/MEK/ERK pathway in rumen epithelium of goats supplying a high metabolizable energy diet

The objective of this study was to explore the underlying mechanism of insulin‐like growth factor 1 (IGF‐1)–caused cell proliferation of rumen epithelium in goats fed a high metabolizable energy (ME) diet. In this study, young goats were fed either a low ME [LL, n = 9, ME: 0.57 MJ/kg^0.75/day] or high ME [HL, n = 9, ME: 1.00 MJ/(kg^0.75/day)] diet for 42 day. The time duration of G₁‐phase was shortened as a result of enhanced expression of cyclin D1 mRNA in the HL group (p < 0.05). It was suggested that a high ME diet promoted cell transition from G₀/G₁ to S‐phase via cyclin D1. The level of phosphorylation of ERK was higher in HL than LL group (p < 0.05). In cell culture, the ERK was phosphorylated by IGF‐1 treatment. The proliferative effects of insulin‐like growth factor 1 (IGF‐1, 25 ng/ml) on [³H] thymidine (TdR) incorporation into DNA and on cyclin D1 protein expression of rumen epithelial cells were inhibited by PPP (the inhibitor of type 1 IGF receptor) (p < 0.05) and ERK inhibitor (p < 0.05) in vitro. Thus, IGF‐1 up‐regulated cyclin D1 expression and accelerated G₁‐phase progression in the cell cycle through Ras/Raf/MEK/ERK pathway in rumen epithelium of goats.     

The development and integrity of equine pre‐antral follicles cultured in vitro with follicle‐stimulating hormone (FSH) supplementation

This study investigated the effects of different concentrations of FSH (10, 50, 100 and 200 ng/ml) in supplemented MEM+ on the development of equine pre‐antral follicles that were cultured in vitro for 2 or 6 days. The ovaries (n = 5) from mares in seasonal anoestrus were collected from a local abattoir. Ten ovarian tissue fragments of approximately 3 × 3 × 1 mm were obtained from each animal. The fragments were cultured in situ for 2 days (D2) or 6 days (D6) in MEM+ or MEM+ supplemented with FSH at four different concentrations, establishing the following 11 groups: control (D0); MEM + (D2); MEM + (D6); MEM + 10 ng/ml of FSH (D2); MEM + 10 ng/ml of FSH (D6); MEM + 50 ng/ml of FSH (D2); MEM + 50 ng/ml of FSH (D6); MEM + 100 ng/ml of FSH (D2); MEM + 100 ng/ml of FSH (D6); MEM + 200 ng/ml of FSH (D2); and MEM + 200 ng/ml of FSH (D6). Follicles were observed in only 9.65% (388 of 4,018) of the histological sections. Of the 861 follicles evaluated, 488 were in the primordial stage, and 373 were in various developmental stages; 59.7% were morphologically normal. Regarding the integrity of the pre‐antral follicles, the groups with 100 ng/ml FSH of 2‐days culture as well as 50, 100 and 200 ng/ml FSH of 6‐days culture provided the best results. In conclusion, the in vitro culture of abattoir‐derived equine ovarian fragments presented better morphological integrity when supplemented with FSH for 6 days, in comparison with the MEM culture group. However, no clear effects were observed with FSH regarding the promotion of activation from a primordial to a developing follicle.     

Serum vitamin D,calcium, and phosphorus concentrations in ponies,horses and foals from the United States and Thailand

Vitamin D is essential in calcium and phosphorus regulation, bone physiology, cell proliferation and epithelial integrity. Literature on vitamin D in growing horses is sparse, and the effect of age on vitamin D has not been evaluated in equids in the United States or in tropical countries. The goal of this study was to determine if there was an effect of age on serum 25(OH)D₃ concentrations in equids in the US (Ohio/Kentucky) and Thailand (Chiang Rai and Kanchanaburi) during the same time of the year. Blood samples were collected from healthy ponies (n = 21) and Thoroughbred foals (n = 13), yearlings (n = 10), and horses (n = 20) in Thailand and from Thoroughbred foals (n = 10) and horses (n = 17) in the US. Serum concentrations of 25(OH)D₃, calcium and phosphorus were measured.In both countries, serum 25(OH)D₃ concentrations were lower in foals than in yearlings and adult horses. Serum 25(OH)D₃ concentrations were higher in horses than in ponies in Thailand, but were not different between horses from either country. Calcium concentrations were not different between groups or location. In both countries, phosphorus concentrations were higher in foals than in older groups; however, were not different between ponies and horses. This study shows that independent of geography there are age-related differences in 25(OH)D₃ concentrations in horses and further confirms that 25(OH)D₃ concentrations are lower in horses compared to other species. The information will serve as the basis for future clinical studies and to help understand better the pathophysiology of equine disorders associated with calcium and phosphorus dysregulation.     

Stability of creatine monohydrate and guanidinoacetic acid during manufacture (retorting and extrusion) and storage of dog foods

The stability of creatine monohydrate (CrMH), crystallised guanidinoacetic acid (GAA‐C) and granulated GAA (GAA‐G) in a moist retorted and a dry extruded dog food formulation during production and storage was investigated. Commercial food mixtures were supplemented with CrMH, GAA‐C or GAA‐G. Uniformity after mixing and retorting or extrusion was determined based on replicate samples (moist n = 8, dry n = 10). Storage stability was evaluated at 25°C/60% relative humidity for 15 months and 40°C/75% for 6 months. Foods with CrMH were analysed for creatine (Cr) and creatinine (Crn), whereas GAA‐C and GAA‐G foods were analysed for GAA concentrations. Coefficients of variation (CV) for uniformity of the additives after mixing of moist and dry pet food formulations were below 15%, and the CV was lower in processed mixtures. Recoveries after retorting and extrusion were higher for GAA‐G (79 and 99%) and GAA‐C (89 and 86%) compared to CrMH (36 and 85%) foods. In moist CrMH food, Cr concentrations re‐increased by 54% whilst Crn concentrations decreased by 39% after storage at 25°C for 15 months. With total molar Cr + Crn remaining stable throughout storage, Crn and Cr appeared to effectively interconvert. Storage of the extruded CrMH food at 25°C for 15 months resulted in a 63% decrease in Cr and a 39% increase in Crn concentration. The decrease in Cr concentration was larger at 6 months storage at 40°C compared to 15 months storage at 25°C. Both GAA‐C and GAA‐G moist and dry foods were stable during storage (<10% decrease). This study showed that GAA is highly stable during production and storage of moist and dry canine foods whilst CrMH is relatively unstable, particularly during storage. The latter makes it difficult to establish a guaranteed Cr content in finished moist retorted and dry extruded foods with CrMH.     

Association of Vitamin D Status and Clinical Outcome in Dogs with a Chronic Enteropathy

Background

Dogs with a chronic enteropathy (CE) have a lower vitamin D status, than do healthy dogs. Vitamin D status has been associated with a negative clinical outcome in humans with inflammatory bowel disease.

Objectives

To examine the relationship between serum 25 hydroxyvitamin D (25(OH)D) concentrations at diagnosis and clinical outcome in dogs with a CE.

Animals

Forty‐one dogs diagnosed with CE admitted to the Royal Dick School of Veterinary Studies, Hospital for Small Animals between 2007 and 2013.

Methods

Retrospective review. Serum 25(OH)D concentrations were compared between dogs which were alive at follow up or had died because of non‐CE‐related reasons (survivors) and dogs which died or were euthanized due to their CE (non‐survivors). A binary logistic regression analysis was performed to determine significant predictors of death in dogs with CE.

Results

Serum concentrations of 25(OH)D at the time a CE was diagnosed were significantly lower in nonsurvivors (n = 15) (median nonsurvivors 4.36 ng/mL, interquartile range 1.6–17.0 ng/mL), median survivors (n = 26) (24.9 ng/mL interquartile range 15.63–39.45 ng/mL, P < .001). Serum 25(OH)D concentration was a significant predictor of death in dogs with CE (odds ratio 1.08 [95% CI 1.02–1.18)]).

Conclusions

Serum 25(OH)D concentrations at diagnosis are predictive of outcome in dogs with CE. The role of vitamin D in the initiation and outcome of chronic enteropathies in dogs is deserving of further study.     

Effect of diet on serum 25-hydroxyvitamin D concentration in the short-beaked echidna (Tachyglossus aculeatus)

Background Elevated concentrations of 25‐hydroxyvitamin D (25(OH)‐D) were diagnosed in captive short‐beaked echidnas (Tachyglossus aculeatus) from three different zoological facilities within Australia. Results The mean serum 25(OH)‐D concentration in the wild echidnas was 24.7 nmol/L and was significantly higher in captive echidnas from all three facilities: Facility 1, mean 335.5 nmol/L (P < 0.001); Facility 2, mean 187.2 nmol/L (P = 0.003); Facility 3, mean 194 nmol/L (P = 0.005). Animals did not appear to have clinical manifestations of vitamin D toxicosis. The increased serum 25(OH)‐D concentration was attributed to excessive dietary intake and a reduction in the amount of vitamin D₃ in the diet of echidnas from Facility 1 resulted in a marked decrease in the serum 25(OH)‐D concentrations (mean 33 nmol/L). The reduction in serum 25(OH)‐D concentration was statistically significant (P = 0.002) and the resulting concentrations were similar to those of wild echidnas (P = 0.212). Conclusion It is not known what effect an elevated serum 25(OH)‐D concentration has on echidnas.     

Lack of glucuronidation products of trans‐resveratrol in plasma and urine of cats

Resveratrol has generated interest in cats due to reported health benefits. Cats have low activity of β‐glucuronidase, and we hypothesized they could not form two common resveratrol metabolites, resveratrol‐3‐O‐glucuronide and resveratrol‐4′‐O‐glucuronide. Resveratrol, 3 mg/cat/day, was given orally to intact male (n = 5) and female cats (n = 5) for 4 weeks. A control group (8 intact males) was used for comparison. Plasma and urine were collected weekly and analysed using high‐pressure liquid chromatography coupled with tandem mass spectrometry. Resveratrol and resveratrol‐3‐O‐sulphate, but no glucuronide metabolites, were detected in plasma and urine. Median (range 10–90th percentile) plasma resveratrol for control and treatment groups was 0.46 ng/ml (0.02–1.74 ng/ml) and 0.96 ng/ml (0.65–3.21 ng/ml). Median (range) plasma resveratrol‐3‐O‐sulphate for control and treatment groups was 6.32 ng/ml (2.55–10.29 ng/ml) and 11.45 ng/ml (1.47–53.29 ng/ml). Plasma resveratrol differed from control in week 4, while plasma resveratrol‐3‐O‐sulphate was different in all weeks (p < 0.05). Median (range) urine resveratrol for control and treatment groups was 0.28 ng/ml (0.05–1.59 ng/ml) and 19.98 ng/ml (8.44–87.54 ng/ml). Median (range) urine resveratrol‐3‐O‐sulphate for control and treatment groups was 26.71 ng/ml (10.50–75.58 ng/ml) and 108.69 ng/ml (11.83–231.05 ng/ml). All time points for urine resveratrol and resveratrol‐3‐O‐sulphate were significantly different from control (p < 0.05), except for weeks 1, 3 and 4 for resveratrol. The results support our hypothesis that cats are unlikely able to glucuronidate resveratrol, most likely due to a reduction in the activity of β‐glucuronidase.     

Plasma pharmacokinetics of quinocetone in ducks after oral and intravenous administration

Quinocetone (QCT), an antimicrobial growth promoter, is widely used in food‐producing animals. However, information about pharmacokinetics (PK) of QCT in ducks still remains unavailable up to now. In this study, QCT and its major metabolites (1‐desoxyquinocetone, di‐desoxyquinocetone and 3‐methyl‐quinoxaline‐2‐carboxylic) in ducks were studied using a simple and sensitive UHPLC‐MS/MS assay. Twenty ducks were divided into two groups. (n = 10/group). One group received QCT by oral administration at dose of 40 mg/kg while another group received QCT intravenously at 10 mg/kg. Plasma samples were collected at various time points from 0 to 96 hr. QCT and its major metabolites in duck plasma samples were extracted by 1 ml acetonitrile and detected by UHPLC‐MS/MS, with the gradient mobile phase that consisted of 0.1% formic acid in water (A) and acetonitrile (B). A noncompartment analysis was used to calculate the PK parameters. The results showed that following oral dosing, the peak plasma concentration (C_max) of QCT was 32.14 ng/ml and the area under the curve (AUCINF_obs) was 233.63 (h ng)/ ml. Following intravenous dosing, the C_max, AUCINF_obs and Vss_obs were 96.70 ng/ml, 152.34 (h ng)/ ml and 807.00 L/kg, respectively. These data indicated that the QCT was less absorbed in vivo following oral administration, with low bioavailability (38.43%). QCT and its major metabolites such as 1‐desoxyquinocetone and 3‐methyl‐quinoxaline‐2‐carboxylic were detected at individual time points in individual ducks, while the di‐desoxyquinocetone was not detected in all time points in all ducks. This study enriches basic scientific data about pharmacokinetics of QCT in ducks after oral and intravenous administration and will be beneficial for clinical application in ducks.     

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.     

A longitudinal study on the acceptance and effects of a therapeutic renal food in pet dogs with IRIS‐Stage 1 chronic kidney disease

Currently, nutritional management is recommended when serum creatinine (Cr) exceeds 1.4 mg/dl in dogs with IRIS‐Stage 2 chronic kidney disease (CKD) to slow progressive loss of kidney function, reduce clinical and biochemical consequences of CKD, and maintain adequate nutrition. It is unknown if dietary interventions benefit non‐azotemic dogs at earlier stages. A prospective 12‐month feeding trial was performed in client‐owned dogs with IRIS‐Stage 1 CKD (n = 36; 20 had persistently dilute urine with urine specific gravity (USG) <1.020 without identifiable non‐renal cause; six had persistent proteinuria of renal origin with urine protein creatinine (UPC) ratio >0.5; 10 had both). Ease of transition to therapeutic renal food and effects on renal biomarkers and quality of life attributes were assessed. Dogs were transitioned over 1 week from grocery‐branded foods to renal food. At 0, 3, 6, 9, and 12‐months a questionnaire to assess owner's perception of their pet's acceptance of renal food and quality of life was completed. Renal biomarkers, including serum Cr, blood urea nitrogen (BUN), and symmetric dimethylarginine (SDMA), and USG and UPC ratio were measured. Of 36 dogs initially enrolled, 35 (97%) dogs were transitioned to therapeutic renal food. Dogs moderately or extremely liked the food 88% of the time, ate most or all of the food 84% of the time, and were moderately or extremely enthusiastic while eating 76% of the time. All renal biomarkers (Cr, BUN, and SDMA) were decreased (p ≤ .05) from baseline at 3‐months, and remained decreased from baseline at 12‐months in dogs completing the study (n = 20). Proteinuria was reduced in 12 of 16 dogs (p = .045) with proteinuria. Owners reported improvement in overall health and quality of life attributes, and hair and coat quality (all p < .01). In summary, dogs with IRIS‐Stage 1 CKD readily transition to renal food. Decreasing serum biomarker concentrations and reduction in proteinuria suggest stabilized kidney function.