Objective: To determine the effects of topically applied 2% delta-9-tetrahydrocannabinol (THC) ophthalmic solution on aqueous humor flow rate (AHFR) and intraocular pressure (IOP) in clinically normal dogs. Animals: 21 clinically normal dogs. Procedures: A randomized longitudinal crossover design was used. Following acquisition of baseline IOP (morning and evening) and AHFR (afternoon only) data, dogs were randomly assigned to 2 treatment groups and received 1 drop of either 2% THC solution or a control treatment (olive oil vehicle) to 1 randomly selected eye every 12 hours for 9 doses. The IOPs and AHFRs were reassessed after the final treatment. Following a washout period of ≥ 7 days, dogs were administered the alternate treatment in the same eye, and measurements were repeated. Results: Mean ± SD IOPs in the morning were 15.86 ± 2.48 mm Hg at baseline, 12.54 ± 3.18 mm Hg after THC treatment, and 13.88 ± 3.28 mm Hg after control treatment. Mean ± SD IOPs in the evening were 13.69 ± 3.36 mm Hg at baseline, 11.69 ± 3.94 mm Hg after THC treatment, and 12.13 ± 2.99 mm Hg after control treatment. Mean IOPs were significantly decreased from baseline after administration of THC solution but not the control treatment. Changes in IOP varied substantially among individual dogs. Mean ± SD AHFRs were not significantly different from baseline for either treatment. Conclusions and Clinical Relevance: Topical application of 2% THC ophthalmic solution resulted in moderate reduction of mean IOP in clinically normal dogs. Further research is needed to determine efficacy in dogs with glaucoma.

Most of the metabolic diseases of dairy cows occur within the first 2 wk after calving, and cows with a metabolic disease are prone to infectious diseases. Although metabolic diseases are generally recognized as a risk factor for infectious diseases owing to the associated decrease in immune function, the difference in immune status between cows with milk fever (MF) or displaced abomasum (DA) during the lactation period has not been clarified. Therefore, the peripheral blood leukocyte populations in 38 multiparous Holstein cows from 1 herd were analyzed after calving. The cows were divided into 3 groups according to health: 21 cows that remained clinically healthy throughout the experimental period (control group), 9 cows that had MF on the day of calving, and 8 cows with an onset of DA within 4 wk after calving. The T- and B-cell numbers were lowest at week 0, and they increased gradually after calving. There was no significant difference between the 3 groups in the number of each subset of leukocytes on the day of calving, but the number of CD8+ T-cells was significantly lower in the MF and DA groups than in the control group at week 1. The numbers of CD4+, CD8+, and WC1+ T-cells tended to be lower in the DA group than in control group from weeks 4 to 12, a tendency not observed in the MF group. These data suggest that when cows have DA around the time of calving, their lymphocyte numbers remain lower until 12 wk after calving.

Hemorrhagic pneumonia is an acute and fatal disease of farmed mink caused by Pseudomonas aeruginosa. The pathogenesis of this disease has not yet been resolved. Mink are the only animals known to be susceptible to acute, contagious, and fatal lung infections caused by P. aeruginosa. The purpose of this study was to investigate the correlation between dose-response and season of infection and to clarify whether Danish mink are carriers of P. aeruginosa on their nasal mucosa during the season for hemorrhagic pneumonia. To elucidate the pathogenesis of the disease, an infectious dose-response trial was carried out on adult mink and mink kits, both in the season for hemorrhagic pneumonia (November) as well as out of season (July). It proved difficult to infect mink via the intra-nasal route. Only 4 out of 60 infected mink developed clinical disease and were euthanized, all of them in November, illustrating that predisposing factors in the mink itself and not infectious dose might be crucial for disease development. We were able to culture P. aeruginosa from the nasal cavity of the clinically healthy experimental mink 8 d after inoculation. This indicated that the mink can carry P. aeruginosa on their nasal mucosa without developing the disease. It was not possible, however, to culture P. aeruginosa from the nasal cavity of clinically healthy mink obtained from farms in November, which indicates that the organism is not a normal part of the nasal mucosal flora of mink.

There is evidence that vitamin E (VE) has anti-inflammatory and analgesic properties in human osteoarthritis (OA). This double-blinded and randomized pilot study used a broad spectrum of clinical and laboratory parameters to investigate whether such beneficial effects could be detected in a canine experimental OA model. Dogs were divided into 2 groups: control (n = 8), which received a placebo, and test group (n = 7), which received 400 IU/animal per day of VE for 55 d, starting the day after transection of the cranial cruciate ligament. Lameness and pain were assessed using a visual analogue scale (VAS), numerical rating scale (NRS), and electrodermal activity (EDA) at day 0, day 28, and day 55. Cartilage and synovial inflammation lesions were assessed. One-side comparison was conducted at an alpha-threshold of 10%. At day 56, dogs were euthanized and concentrations of prostaglandin E2 (PGE2), nitrogen oxides (NOx), and interleukin-1 beta (IL-1β) were measured in synovial fluid. Concentrations of NOx and PGE2 in synovial fluid were lower in the test group (P < 0.0001 and P = 0.03, respectively). Values of VAS, NRS, and EDA showed a consistent trend to be lower in the test group than in the control, while statistical significance was reached for VAS at day 55 and for EDA at day 28 (adjusted P = 0.07 in both cases). Histological analyses of cartilage showed a significant reduction in the scores of lesions in the test group. This is the first time that a study in dogs with OA using a supplement with a high dose of vitamin E showed a reduction in inflammation joint markers and histological expression, as well as a trend to improving signs of pain.

Objective—To evaluate with CT the efficacy of various combinations of firearms and ammunitions to penetrate and disrupt the brain tissue of cadaveric heads of feedlot steers. Sample—42 fresh cadaveric heads of 12- to 18-month-old Bos taurus steers. Procedures—For each of 7 combinations of firearms and ammunitions (.22-caliber rifle firing a long rifle 30-grain plated lead solid- or hollow-point round, .223-caliber carbine firing a 50-grain ballistic-tip round, 9-mm pistol firing a 124-grain total metal jacket round, .45-caliber automatic Colt pistol [ACP] firing a 230-grain full metal jacket round, and 12-gauge shotgun firing a 2.75-inch 1.25-ounce No. 4 birdshot shell or a 1-ounce rifled slug), 6 cadaveric heads were shot at an identical distance (3 m), angle, and anatomic location. Heads were scanned with third-generation CT, and images were evaluated to determine extent of penetration, projectile fragmentation, cranial fracture, and likelihood of instantaneous death (≥ 30% destruction of brain tissue or a brainstem lesion). Results—41 of 42 skulls were penetrated by the projectile. Instantaneous death was considered a likely consequence for 83% (25/30) of heads shot with a rifle-fired .22-caliber solid-point round, pistol-fired .45-caliber ACP round, carbine-fired .223-caliber round, and shotgun-fired birdshot and slug. Of the 18 heads shot with pistol-fired 9-mm and .45-caliber ACP rounds and rifle-fired .22-caliber hollow-point rounds, only 6 had brainstem lesions. Conclusions and Clinical Relevance—Results suggested that gunshots delivered by all firearm-ammunition combinations except rifle-fired .22-caliber hollow-point rounds and pistol-fired 9-mm rounds were viable options for euthanasia of feedlot cattle.

The objectives were to determine the effects of feeding supplements rich in omega-6 or omega-3 fatty acids (FA) during the late gestation to the early postpartum and breeding periods on reproduction and milk FA profile in beef cows. For each of two years, at the beginning of period 1 (mid-December), 72 beef cows, calving in January or February, were assigned to diets supplemented with roasted flaxseed (Flax) or roasted soybean (Soybean). For each of two years, after 11 wk (end of period 1), 18 cows of 36 in the Flax group were switched to the soybean supplement and 18 cows of 36 in the Soybean group were switched to the flax supplement (start of Period 2). Cows were bred by timed artificial insemination (TAI) in week 5 of period 2. The FA composition of the milk reflected the FA profile of the oilseed supplements. There were no differences in pregnancy rates among the 4 groups. The treatments had no effect on plasma prostaglandin metabolite levels or ratios at 4 to 11 d postpartum. At 5 to 6 d post- TAI, pregnant cows fed Flax in period 1 had lower (P < 0.05) plasma prostaglandin F metabolite (PGFM) levels and PGFM to prostaglandin E metabolite (PGEM) ratio than cows fed Soybean, but there were no significant differences at 19 to 20 d post-TAI. Cows pregnant from TAI and fed Flax in period 2 had higher (P < 0.05) serum progesterone levels at 5 to 6 d post-TAI than cows fed Soybean, but there was no difference at 19 to 20 d post-TAI. The dietary treatments had no effect on pregnancy rates, but there were some effects on plasma PGFM levels, PGFM to PGEM ratios, and serum progesterone levels. The FA supplements influenced the FA composition of milk.

This study investigated epigenetic mechanisms by which DNA methylation affects the function of bovine adaptive immune system cells, particularly during the peripartum period, when shifts in type 1 and type 2 immune response (IR) biases are thought to occur. Stimulation of CD4+ T-lymphocytes isolated from 5 Holstein dairy cows before and after parturition with concanavalin A (ConA) and stimulation of CD4+ T-lymphocytes isolated from 3 Holstein dairy cows in mid-lactation with ConA alone or ConA plus dexamethasone (Dex) had significant effects on production of the cytokines interferon gamma (IFN-γ, type 1) and interleukin 4 (IL-4, type 2) that were consistent with DNA methylation profiles of the IFN-γ gene promoter region but not consistent for the IL-4 promoter region. ConA stimulation increased the production of both cytokines before and after parturition. It decreased DNA methylation in the IFN-γ promoter region but increased for IL-4 promoter region. Parturition was associated with an increase in IFN-γ production in ConA-stimulated cells that approached significance. Overall, DNA methylation in both promoter regions increased between the prepartum and postpartum periods, although this did not correlate with secreted cytokine concentrations. Dexamethasone treated cells acted in a manner consistent with the glucocorticoid’s immunosuppressive activity, which mimicked the change at the IFN-γ promoter region observed during parturition. These results support pregnancy as type 2 IR biased, with increases of IFN-γ occurring after parturition and an increase in IL-4 production before calving. It is likely that these changes may be epigenetically controlled.

Objective: To measure and compare insulin secretion and sensitivity in healthy alpacas and llamas via glucose clamping techniques. Animals: 8 llamas and 8 alpacas. Procedures: Hyperinsulinemic euglycemic clamping (HEC) and hyperglycemic clamping (HGC) were performed on each camelid in a crossover design with a minimum 48-hour washout period between clamping procedures. The HEC technique was performed to measure insulin sensitivity. Insulin was infused IV at 6 mU/min/kg for 4 hours, and an IV infusion of glucose was adjusted to maintain blood glucose concentration at 150 mg/dL. Concentrations of blood glucose and plasma insulin were determined throughout. The HGC technique was performed to assess insulin secretion in response to exogenous glucose infusion. An IV infusion of glucose was administered to maintain blood glucose concentration at 320 mg/dL for 3 hours, and concentrations of blood glucose and plasma insulin were determined throughout. Results: Alpacas and llamas were not significantly different with respect to whole-body insulin sensitivity during HEC or in pancreatic β-cell response during HGC. Alpacas and llamas had markedly lower insulin sensitivity during HEC and markedly lower pancreatic β-cell response during HGC, in comparison with many other species. Conclusions and Clinical Relevance: New World camelids had lower glucose-induced insulin secretion and marked insulin resistance in comparison with other species. This likely contributes to the disorders of fat and glucose metabolism that are common to camelids.

Objective: To determine whether 14-day topical ocular administration of high doses of feline recombinant interferon omega (FelFN) or human recombinant interferon alpha-2b (HulFN) solution improves clinical disease and decreases virus shedding in cats with naturally acquired viral keratoconjunctivitis. Animals: 36 cats with upper respiratory tract disease and ocular involvement. Procedures: Cats received 1 drop of FelFN solution (1 × 10(6) U/mL), HulFN solution (1 × 10(6) U/mL), or saline (0.9% NaCl) solution (12 cats/group) in each eye twice daily for 14 days (beginning day 1). Oropharyngeal and conjunctival swab samples were collected from each cat before (day 0) and on day 14 of treatment for virus isolation (VI) and real-time quantitative PCR (RT-qPCR) testing to detect feline herpesvirus-1 and feline calicivirus. Subjective clinical scores were recorded on days 0, 3, 7, 10, and 14. Results: The number of cats for which feline herpesvirus-1 was detected via VI or RT-qPCR assay was generally (albeit not always significantly) lower on day 14, compared with day 0 findings; however, findings on days 0 or 14 did not differ among groups. The number of cats for which feline calicivirus was detected via VI or RT-qPCR assay did not differ significantly between days 0 and 14 for any group. Clinical scores significantly decreased over the 14-day period but did not differ among groups. Conclusions and Clinical Relevance: In cats with naturally occurring viral keratoconjunctivitis, bilateral ocular administration of high doses of FelFN or HulFN twice daily for 14 days did not improve clinical disease or virus shedding, compared with treatment with saline solution.

Objective: To determine the incidence of bacteremia, as detected by routine methods for bacterial culture of blood samples, following routine endoscopic biopsy of the stomach and duodenum in healthy research dogs and to determine whether treatment with omeprazole administration affected the incidence of bacteremia. Animals: 8 healthy purpose-bred research dogs. Procedures: All dogs underwent gastroduodenoscopy with biopsy at 4 points: twice prior to treatment with omeprazole, once following 15 days of omeprazole treatment (20 mg, PO, q 12 h), and once 14 days after treatment ceased. Dogs had a mean ± SD body weight of 18.6 ± 2.0 kg. Blood samples were aseptically obtained at 3 points during each procedure (before, immediately following, and 24 hours after endoscopy), and routine aerobic and anaerobic bacterial culture of blood was performed. Results: 96 cultures were attempted for each culture method, yielding positive results of aerobic culture for 2 dogs at separate time points and no positive results of anaerobic culture. Conclusions and Clinical Relevance: Routine gastrointestinal endoscopy with biopsy in healthy dogs did not result in a detectable bacteremia in most dogs. Treatment with the gastric acid–suppressing medication omeprazole did not affect the incidence of bacteremia as detected via standard techniques.