The effect of aquapuncture at Pericardium 6 (PC-6) on dexmedetomidine-induced nausea and vomiting in cats.

OBJECTIVE: To determine the effect of aquapuncture at acupuncture point Pericardium 6 (PC-6) on the incidence of dexmedetomidine-induced vomiting and nausea in cats. STUDY DESIGN: Randomized, prospective, crossover study. ANIMALS: A group of 22 cats, 14 females and eight males, aged 1-12 years and weighing 3.8-5.9 kg. METHODS: Each cat was administered treatments in random order at ≥1 week intervals. For treatment (DEX-A), cats were administered PC-6 stimulation by aquapuncture (0.25 mL/250 µg vitamin B12 injection subcutaneously at PC-6). After 30 minutes, dexmedetomidine (10 µg kg-1) was administered intramuscularly (IM). For control treatment (DEX), cats were administered only dexmedetomidine (10 µg kg-1) IM. Incidence of vomiting, number of vomiting episodes and time to first vomiting were recorded by an observer unaware of treatment allocation. At 30 minutes after dexmedetomidine administration, atipamezole (0.1 mg kg-1) was injected IM. Behavior was video recorded and later scored by two observers for clinical signs of nausea. A regression model (analysis of covariance) was used to detect the influence of aquapuncture on vomiting and nausea. Significance was set at p < 0.05. RESULTS: Of 21 cats, 18 (85%) and 16 cats (76%) vomited in DEX-A and DEX, respectively. There was no significant difference in the incidence of vomiting (p = 0.55), number of vomiting episodes (p = 0.55), mean time to vomit (p = 0.88) or nausea score (p = 0.51) between DEX-A and DEX. CONCLUSIONS AND CLINICAL RELEVANCE: PC-6 aquapuncture did not reduce the incidence of dexmedetomidine-induced vomiting or severity of nausea in cats.

Retrospective evaluation of the effectiveness of xylazine for inducing emesis in cats: 48 cats (2011-2015).

OBJECTIVE: To determine the effectiveness of xylazine for the induction of emesis in cats that were suspected of ingesting potentially toxic substances or foreign objects. DESIGN: Retrospective study. SETTING: Private emergency and specialty referral hospital. ANIMALS: Forty-eight client-owned cats that were administered xylazine to induce emesis for decontamination of a toxic substance or expulsion of an ingested foreign object. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: The medical records of 48 cats presenting for known or suspected ingestion of foreign material that underwent decontamination with xylazine were reviewed. Signalment, material ingested, dose and route of xylazine administration, success of emesis and recovery of foreign material ingested, use of a reversal agent, and adverse effects were noted. The induction of emesis was successful in 29/48 (60%) of cats. Sedation was the most common adverse effect and was noted in 15/48 (31%) of patients. CONCLUSIONS: Xylazine is safe and reasonably effective at inducing emesis in cats.

Evaluation and comparison of xylazine hydrochloride and dexmedetomidine hydrochloride for the induction of emesis in cats: 47 cases (2007-2013).

OBJECTIVE: To evaluate and compare i.m. administration of xylazine hydrochloride and dexmedetomidine hydrochloride for the induction of emesis in cats. DESIGN: Retrospective case series. ANIMALS: 47 cats with a history of suspected ingestion of a toxic substance or foreign material between June 2007 and June 2013. PROCEDURES: Data collected for analysis from the medical records included signalment, drug dose and route of administration, whether a repeated dose of the emetic agent was administered, and outcome (emesis, yes or no). RESULTS: Cats in the 2 treatment groups did not differ with regard to age, sex, or breed distribution. The range of doses of xylazine administered i.m. was 0.36 to 0.64 mg/kg (0.16 to 0.29 mg/lb). The range of doses of dexmedetomidine administered i.m. was 6 to 18 µg/kg (2.7 to 8.2 µg/lb). A repeated dose of xylazine or dexmedetomidine was given to 3 and 1 cats, respectively. Emesis was successfully induced in 24 of the 47 (51.1%) cats. Nine of the 21 (43%) cats that received xylazine vomited and 15 of the 26 (58%) cats that received dexmedetomidine vomited. Percentage of cats that vomited after either drug administration did not differ significantly. CONCLUSIONS AND CLINICAL RELEVANCE: Following i.m. administration in cats, xylazine and dexmedetomidine were similarly effective for induction of emesis, indicating that dexmedetomidine is a comparable alternative to xylazine for this purpose. Prospective studies are needed to determine the optimal i.m. dose of dexmedetomidine for induction of emesis in cats.

The effects of acupuncture point Pericardium 6 on hydromorphone-induced nausea and vomiting in healthy dogs.

OBJECTIVE: To evaluate the effect of needling at acupuncture point Pericardium 6 on hydromorphone-induced nausea and vomiting. STUDY DESIGN: Randomized controlled clinical study. ANIMALS: Eighty-one mixed-breed, healthy dogs aged 1.8 ± 1.6 years and weighing 14.5 ± 5.6 kg, admitted for elective ovariohysterectomy (n = 75) or castration (n = 6). METHODS: Dogs were randomly assigned to one of three groups: acupuncture at Pericardium 6 (AT, n = 27); alternative acupuncture at Lung 5 (ST, n = 27), and no acupuncture (CT, n = 27). During time 0-30 minutes (baseline), occurrences of hypersalivation, vomiting and licking were recorded. At 30 minutes, subjects were administered hydromorphone (0.1 mg kg(-1) ) in combination with acepromazine (0.03 mg kg(-1) ) intramuscularly. During time 30-45 minutes (post-injection), occurrences of hypersalivation, vomiting and licking were recorded by an observer unaware of group assignment. Groups were compared using a Kruskal-Wallis test followed by a Dunn's post-test, or Fisher's exact tests when appropriate. RESULTS: There were no significant differences in age, weight or baseline observations among groups. Vomiting incidence post-injection was higher in the CT (20/27, 74.1%) and ST (22/27, 81.5%) groups than in the AT (10/27, 37.0%) group (p = 0.0129 and p = 0.002, respectively). The number of vomiting episodes [median (range)] after opioid administration was higher in the ST [1 (1-6)] than the AT [0 (0-2)] group (p = 0.0040). There were no differences in the median number of vomiting episodes between the ST and CT [1 (0-3)] or AT and CT groups. There were no differences in hypersalivation or licking among groups after hydromorphone-acepromazine administration. CONCLUSIONS AND CLINICAL RELEVANCE: Pericardium 6 acupuncture reduced the incidence of hydromorphone-induced vomiting in healthy dogs. This cost-effective technique can improve patient well-being and comfort during the perioperative period.

Assessment of dexmedetomidine and other agents for emesis induction in cats: 43 cases (2009-2014).

OBJECTIVE: To compare the use of dexmedetomidine hydrochloride, xylazine hydrochloride, and hydrogen peroxide for emesis induction in cats. DESIGN: Retrospective case series. ANIMALS: 43 client-owned cats for which emesis induction was attempted because of known or suspected toxicant ingestion or recent ingestion of a string foreign body. PROCEDURES: Data collected from the cats' medical records included type, dose, and route of administration of emetic agent; outcome of attempted emesis induction; time until emesis or postemesis administration of a reversal agent (to counter sedative effects of the emetic agent); and adverse events. RESULTS: Emesis induction was attempted by oral administration of hydrogen peroxide (n = 3) or IM or IV administration of xylazine (25 [including 1 cat that had already received hydrogen peroxide]) or dexmedetomidine (16). No cat that received hydrogen peroxide vomited. Emesis was induced in 11 of 25 xylazine-treated cats and in 13 of 16 dexmedetomidine-treated cats. Dexmedetomidine was more likely to cause vomiting than xylazine (OR, 5.5; 95% confidence interval, 1.1 to 36). The median dose of dexmedetomidine that caused emesis was 7.0 µg/kg (3.2 µg/lb; range, 0.96 to 10.0 µg/kg [0.44 to 4.55 µg/lb]). The elapsed time until emesis or postemesis reversal agent administration was recorded for 5 xylazine-treated cats (median interval, 10 minutes [range, 5 to 175 minutes]) and 10 dexmedetomidine-treated cats (median interval, 5 minutes [range, 1 to 12 minutes]). Sedation was the only adverse effect, occurring in 2 xylazine-treated cats and 1 dexmedetomidine-treated cat. CONCLUSIONS AND CLINICAL RELEVANCE: Results indicated that dexmedetomidine can be used successfully to induce emesis in cats.

Effects of maropitant, acepromazine, and electroacupuncture on vomiting associated with administration of morphine in dogs.

OBJECTIVE: To evaluate effects of maropitant, acepromazine, and electroacupuncture on morphine-related signs of nausea and vomiting in dogs and assess sedative effects of the treatments. DESIGN: Randomized controlled clinical trial. ANIMALS: 222 dogs. PROCEDURES: Dogs received 1 of 6 treatments: injection of saline (0.9% NaCl) solution, maropitant citrate, or acepromazine maleate or electroacupuncture treatment at 1 acupoint, 5 acupoints, or a sham acupoint. Morphine was administered after 20 minutes of electroacupuncture treatment or 20 minutes after injectable treatment. Vomiting and retching events and signs of nausea and sedation were recorded. RESULTS: Incidence of vomiting and retching was significantly lower in the maropitant (14/37 [37.8%]) group than in the saline solution (28/37 [75.7%]) and sham-acupoint electroacupuncture (32/37 [86.5%]) groups. The number of vomiting and retching events in the maropitant (21), acepromazine (38), 1-acupoint (35), and 5-acupoint (34) groups was significantly lower than in the saline solution (88) and sham-acupoint electroacupuncture (109) groups. Incidence of signs of nausea was significantly lower in the acepromazine group (3/37 [8.1%]) than in the sham-acupoint group (15/37 [40.5%]). Mean nausea scores for the saline solution, maropitant, and sham-acupoint electroacupuncture groups increased significantly after morphine administration, whereas those for the acepromazine, 1-acupoint electroacupuncture, and 5-acupoint electroacupuncture groups did not. Mean sedation scores after morphine administration were significantly higher in dogs that received acepromazine than in dogs that received saline solution, maropitant, and sham-acupoint electroacupuncture treatment. CONCLUSIONS AND CLINICAL RELEVANCE: Maropitant treatment was associated with a lower incidence of vomiting and retching, compared with control treatments, and acepromazine and electroacupuncture appeared to prevent an increase in severity of nausea following morphine administration in dogs.

Clinical experience with a lipid-free, ready-made parenteral nutrition solution in dogs: 70 cases (2006-2012).

OBJECTIVE: To review the clinical use of a lipid-free, ready-made amino acid and glucose parenteral nutrition (PN) solution in dogs. DESIGN: Retrospective study of dogs from 2006 to 2012 that received this form of PN. SETTING: University veterinary teaching hospital. ANIMALS: Seventy dogs presented to the hospital for treatment of various diseases in which PN was used as part of patient management. Dogs were administered PN at the discretion of the primary clinician. INTERVENTION: A lipid-free, ready-made solution containing amino acid (59 g/L) and dextrose (100 g/L) was administered intravenously as a constant rate infusion to provide nutritional support. MEASUREMENTS AND MAIN RESULTS: PN was provided for a median of 2.2 days (range 0.5-9.5 days) in the 70 dogs, totaling 168 days of PN. The PN provided a median of 5.5 g/100 kcal of protein (range 1-9.5 g/100 kcal) and a median of 2.2 mg/kg of bodyweight per minute (range 0.8-5.2 mg/kg/min) of glucose, which reflected a median of 57% of the resting energy requirement (range 9-100%). Metabolic complications developed in 43 of 67 dogs where these data were recorded, but the development of hyperkalemia was the only complication associated with a poor outcome (eg, death or euthanasia). Mechanical complications were seen in 28 dogs, and all but one of these occurred when PN was delivered through peripheral catheters. Septic complications were confirmed in 5 dogs. CONCLUSIONS: This form of PN is suitable for clinical use and can provide both protein and calories to ill dogs. It was, however, associated with a high rate of complications and requires careful patient monitoring.

Antiemetic efficacy of promethazine on xylazine-induced emesis in cats.

The prophylactic antiemetic effect of 3 dosages of promethazine injected into cats 1 h before administration of xylazine was compared with that of a saline solution. Prior treatment with 2 and 4 mg/kg of promethazine significantly reduced the frequency of emetic episodes. Promethazine may be used as a prophylactic antiemetic in cats treated with xylazine.

Zinc-carnosine and vitamin E supplementation does not ameliorate gastrointestinal side effects associated with ciclosporin therapy of canine atopic dermatitis.

Chelated zinc-carnosine and vitamin E [GastriCalm(®) (GCM); Teva Animal Health] is marketed as an anti-emetic supplement for dogs to assist the repair of damaged stomach and intestinal mucosa. The purpose of this prospective, double-blinded, placebo-controlled trial was to determine whether GCM reduced the frequency of vomiting, diarrhoea and appetite changes during initiation of ciclosporin (Atopica(®); Novartis Animal Health) therapy for the treatment of canine atopic dermatitis. Sixty privately owned dogs diagnosed with atopic dermatitis were randomly assigned to GCM (n=30) or placebo (n=30) groups. All dogs received ∼ 5 mg/kg ciclosporin (range, 3.5-5.8 mg/kg) once daily. Dogs <13.6 kg received half a tablet of GCM or placebo; dogs ≥ 13.6 kg received one tablet once daily. GastriCalm(®) or placebo was administered 30 min prior to eating, and the ciclosporin was administered 2 h after feeding. Owners recorded episodes of vomiting, diarrhoea and appetite changes. Dogs were examined on days 0 and 14. Forty-one of 60 dogs (68.3%) had at least one episode of vomiting, diarrhoea or appetite change, leaving nine placebo dogs (30%) and ten GCM dogs (33.3%) free of adverse events (AE). Twenty-seven of 60 dogs (45%) vomited, and 15 of 60 (25%) had diarrhoea. There was no significant difference in episodes of individual AEs, but the placebo group had a significantly lower total AE score (summation of episodes of appetite change, vomiting and diarrhoea; P=0.022). Small dogs (<6.82 kg) had significantly fewer total AEs in both treatment groups and tolerated ciclosporin better than larger dogs (P<0.05).

Comparative efficacy of maropitant and selected drugs in preventing emesis induced by centrally or peripherally acting emetogens in dogs.

Maropitant (Cerenia; a novel, selective neurokinin(1) receptor antagonist), chlorpromazine, metoclopramide and ondansetron were compared in two randomized, placebo-controlled studies for efficacy in preventing emesis induced by emetogens acting centrally (apomorphine; Study 1) or peripherally (syrup of ipecac; Study 2) in dogs. In each study, ten male and ten female beagles were treated in a five-treatment, five-period crossover design. The five treatments were 0.9% saline (0.1 mL/kg), maropitant (1 mg/kg), metoclopramide (0.5 mg/kg), or chlorpromazine (0.5 mg/kg) all administered subcutaneously, or ondansetron (0.5 mg/kg) administered intravenously. One hour posttreatment dogs were challenged with apomorphine at 0.1 mg/kg intravenously (Study 1) or syrup of ipecac at 0.5 mL/kg orally (Study 2). Following emetogen challenge, dogs were observed for 30 min (Study 1) or 1 h (Study 2) for emesis. No clinical signs, other than those related to emesis, were observed. Efficacy of maropitant in preventing emesis induced centrally by apomorphine was not different (P > 0.05) from metoclopramide or chlorpromazine but was superior (P < 0.0001) to ondansetron. Efficacy of maropitant in preventing emesis induced by syrup of ipecac was not different (P > 0.05) from ondansetron but was superior (P

Safety and efficacy of oral low-volume sodium phosphate bowel preparation for colonoscopy in dogs.

BACKGROUND: Sodium phosphate (NaP) is a low-volume, hyperosmolar laxative that is an effective bowel-cleansing agent in humans. HYPOTHESIS: NaP will be as safe and efficacious as polyethylene glycol (PEG) bowel preparation for colonoscopy in dogs. ANIMALS: Eight purpose-bred healthy dogs. METHODS: In phase I, standard (NaP and enemas; NaP(1)) and control preparations (PEG and enemas) were compared in a crossover design to determine the safety and efficacy of NaP. Serial clinical and serum analytical evaluations were used to determine the safety of NaP. In phase II, the efficacy of the standard NaP preparation was compared with 3 other NaP variations, which excluded enema or included bisacodyl, with or without enemas in a crossover design. An observer blinded to the bowel preparation assigned a score of 1-4 (1=clean colon; 4=unacceptable colon cleansing preventing adequate endoscopic evaluation) to each of 5 regions of the colon. RESULTS: The mean total colon cleansing score (TCS), defined as the sum of scores from each region, of the control (9.4) was less than NaP(1) (13.6) (P < 0.05). There were no significant differences in regional or TCS for the remaining 4 NaP protocols. NaP(1) resulted in moderate, but clinically occult, hyperphosphatemia and hypocalcemia, which resolved within 24 hours. CONCLUSIONS AND CLINICAL IMPORTANCE: Despite the safety and ease of administration of the NaP preparations, the NaP bowel-cleansing preparations used in this study cannot be recommended for use because of the inadequate quality of bowel preparation compared with the protocol using PEG-containing fluids.

Five common toxins ingested by dogs and cats.

When a dog or cat ingests a common household toxin, rapid decontamination is critical. This article provides treatment recommendations for some of the most common toxicoses in dogs and cats, along with a summary table for quick reference.

Behavioural, biochemical, and pathological responses of possums (Trichosurus vulpecula) poisoned with phosphorus paste.

AIM: To investigate the behavioural, biochemical and pathological responses of possums following poisoning with phosphorus paste, in order to assess the implications for the welfare of possums. METHODS: After ingestion of phosphorus paste by wild-caught possums (18 high dose, nine low dose, and 12 non-poisoned controls), behavioural observations were made at 15-min intervals for 24 h or until death. Serum biochemistry, and gross and microscopic pathology were assessed at 3-hourly intervals in a further 21 possums. RESULTS: Possums that ingested phosphorus paste developed an abnormal posture (high incidence of crouching after 4-8 h), mild congestion of the gastric mucosa, and elevated levels of creatine kinase (CK) in serum after 3-6 h. Retching was observed in 67% possums, and 44% vomited at least once. Possums were prostrate from about 18 h after eating the poison, and the response to handling, an indicator of consciousness, was lost at about 24 h, followed by death at 25 h. CONCLUSION: The main welfare concern was the possibility of discomfort or pain caused by the congestion of the gastric mucosa, as indicated by the crouched posture adopted by poisoned possums. Retching and vomiting may also have caused pain and distress. The degree of pain or discomfort would depend on the degree of congestion of the gastric mucosa, which was typically mild, and on the duration and severity of retching and vomiting, which were typically short and mild. Possums remained conscious until 1 h before death, implying that they were able to experience pain and distress from the effects of ingestion of phosphorus for almost the entire period of illness, which lasted for approximately one day.

Effect of intratesticular injection of xylazine/ketamine combination on canine castration.

This study was performed to compare the effect of intratesticular (IT) injection of xylazine/ketamine combination for canine castration with those of intramuscular (IM) or intravenous (IV) injection. Xylazine and ketamine was administered simultaneously via intratesticularly (IT group), intramuscularly (IM group) or intravenously (IV group) at doses of 2 and 10 mg/kg, respectively. Pain response at the time of injection, mean induction time, mean arousal time, mean walking time and cardiopulmonary function during anesthesia were monitored after the xylazine and ketamine administration. In IV and IM groups, heart rates were significantly decreased 30 and 45 min after xylazine and ketamine administration, respectively (p < 0.05). Respiratory rates were significantly decreased in the IV group (p < 0.05). In the IT group, there was no significant changes in heart and respiratory rates. The occurrence of cardiac arrhythmias was less severe in IT group compared with those in IM and IV groups. The route of administration did not affect rectal temperature. Mean induction time was significantly (p < 0.05) longer in IT group than in IM and IV groups. On the contrary, mean arousal time and mean walking time were shortened in IT group. Clinical signs related to pain response at the time of injection and vomiting were less observed in IT group than in IM group, and head shaking was less shown in IT group than in IM and IV groups during recovery period. These results indicated that intratesticular injection of xylazine/ketamine for castration has several advantages such as less inhibition of cardiopulmonary function and fast recovery from anesthesia without severe complications, and would be an effective anesthetic method for castration in small animal practice.

Lead toxicosis in cats-a review.

Although the incidence of lead toxicosis in small animals continues to decrease, it remains a significant malady. We have reviewed the literature of the past 45 years, which revealed 70 cases involving cats. Sources, signs, diagnosis, pathology and treatment of feline lead toxicosis are reviewed. In 84% of these cases the source of lead was old paint usually from home renovation. The most common signs in cats are anorexia, vomiting, and seizures. The younger individuals seem more likely to show CNS signs. Since signs are often vague, lead toxicosis may be significantly under diagnosed in cats. The gold standard of diagnostic tests is blood lead concentration, although it does not necessarily correlate with total body burden of lead or with metabolic effects including clinical signs. Diagnostic tests including erythropoietic protoporphyrin (EPP), urine aminolevulinic acid, and others are discussed. Gross findings on necropsy are few and include a yellow-brown discoloration of the liver often with a nutmeg-like appearance. Histological examination may reveal pathognomonic inclusion bodies in liver and renal tissues. Characteristic histological changes in the CNS include neuronal necrosis and demyelination. Treatment of lead toxicosis in cats, as in any species, involves removing the exposure, decontaminating the individual and the environment, supportive care and chelation therapy. The most recently available chelator is succimer (meso 2,3-dimercaptosuccinic acid). Succimer given orally is well tolerated and has a wide margin of safety. A high index of suspicion of lead toxicosis is warranted in cats since they often present with vague and non-specific signs. With any consistent history owners need to be asked about home renovation. Early diagnosis and treatment affords a good prognosis.

Treatment of canine atopic dermatitis with a commercial homeopathic remedy: a single-blinded, placebo-controlled study.

A commercial homeopathic remedy and a placebo were administered orally as individual agents to 18 dogs with atopic dermatitis. The pruritus was reduced by less than 50% in only 2/18 dogs; 1 of these dogs was receiving the homeopathic remedy, the other was receiving the placebo. One dog vomited after administration of the homeopathic remedy.

Idiopathic hypercalcemia in cats.

Unexplained hypercalcemia has been increasingly recognized in cats since 1990. In some instances, hypercalcemia has been associated with calcium oxalate urolithiasis, and some affected cats have been fed acidifying diets. We studied the laboratory findings, clinical course, and treatment of 20 cats with idiopathic hypercalcemia. Eight (40%) of the cats were longhaired and all 14 cats for which adequate dietary history was available had been fed acidifying diets. Clinical signs included vomiting (6 cats), weight loss (4 cats), dysuria (4 cats), anorexia (3 cats), and inappropriate urinations (3 cats). Hypercalcemia was mild to moderate in severity. and serum parathyroid hormone concentrations were normal or low. Serum concentrations of phosphorus, parathyroid hormone-related peptide, 25-hydroxycholecalciferol, and calcitriol were within the reference range in most cats. Diseases commonly associated with hypercalcemia (eg, neoplasia, primary hyperparathyroidism) were not identified despite thorough medical evaluations and long-term clinical follow-up. Azotemia either did not develop (10 cats) or developed after the onset of hypercalcemia (3 cats), suggesting that renal failure was not the cause of hypercalcemia in affected cats. Seven of 20 cats (35%) had urolithiasis, and in 2 cats uroliths were composed of calcium oxalate. Subtotal parathyroidectomy in 2 cats and dietary modification in 11 cats did not result in resolution of hypercalcemia. Treatment with prednisone resulted in complete resolution of hypercalcemia in 4 cats.

Surgical treatment of gastric leiomyoma in a dog.

A 12-year-old entire male Maltese terrier was presented with a 1 month history of vomiting and haematemesis. Microcytic hypochromic anaemia was detected. Abdominal radiography, ultrasonography and gastric endoscopy identified a discrete intramural mass in the pyloric antrum. An ulcerated leiomyoma was removed by a partial-thickness intraluminal resection of the gastric wall. The dog recovered well and is free from clinical signs 20 months after surgery.

Zinc-responsive dermatosis in northern-breed dogs: 17 cases (1990-1996).

OBJECTIVE: To determine the response rate of zinc-responsive dermatosis to zinc supplementation, the optimal dosage of zinc required for resolution of lesions, the rate of recurrence of lesions, and to develop recommendations for maintenance dosages of zinc to be administered to dogs with this type of zinc-responsive dermatosis. DESIGN: Retrospective case series. ANIMALS: 17 northern-breed dogs with a diagnosis of zinc-responsive dermatosis. PROCEDURE: Histologic evaluation of skin biopsy specimens and review of medical records. Additional information was obtained from veterinarians and owners via a telephone questionnaire. RESULTS: In 12 of 17 dogs, lesions were unilateral initially, then became symmetrical as the disease progressed. Pyoderma was evident in 5 of 17 dogs, whereas 10 were pruritic. Most lesions initially developed between September and April, and 12 of 17 dogs developed lesions in February, October, and November. Initial dosages of zinc supplement ranged from 0.8 to 4.6 mg/kg of body weight/d (0.36 to 2.09 mg/lb/d). Effective/ maintenance dosages ranged from 0.5 mg/kg (0.23 mg/lb), twice weekly, to 8.0 mg/kg/d (3.6 mg/lb/d). Fifteen of 17 dogs had complete resolution of lesions after zinc supplementation. Lesions recurred in 9 of 16 dogs. Approximately half of the recurrent lesions were a result of a missed dose or a decrease in dosage or frequency of zinc supplementation. CLINICAL IMPLICATIONS: An initial dosage of zinc supplement of 1.0 mg of elemental zinc/kg (0.45 mg of elemental zinc/lb), PO, every 24 hours is recommended. Treatment should be continued for 1 month to determine response to treatment, and the daily dosage should be increased by 50% if the initial dosage is not effective. Dogs are prone to recurrence of lesions if a dose of zinc is missed or the dosage or frequency is decreased.