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In an effort to recognize and address communicable and point-source epidemics in dog and cat populations, this project created a near real-time syndromic surveillance system devoted to companion animal health in the United States. With over 150 million owned pets in the US, the development of such a system is timely in light of previous epidemics due to various causes that were only recognized in retrospect. The goal of this study was to develop epidemiologic and statistical methods for veterinary hospital-based surveillance, and to demonstrate its efficacy by detection of simulated foodborne outbreaks using a database of over 700 hospitals. Data transfer protocols were established via a secure file transfer protocol site, and a data repository was constructed predominantly utilizing open-source software. The daily proportion of patients with a given clinical or laboratory finding was contrasted with an equivalent average proportion from a historical comparison period, allowing construction of the proportionate diagnostic outcome ratio and its confidence interval for recognizing aberrant heath events. A five-tiered alert system was used to facilitate daily assessment of almost 2,000 statistical analyses. Two simulated outbreak scenarios were created by independent experts, blinded to study investigators, and embedded in the 2010 medical records. Both outbreaks were detected almost immediately by the alert system, accurately detecting species affected using relevant clinical and laboratory findings, and ages involved. Besides demonstrating proof-in-concept of using veterinary hospital databases to detect aberrant events in space and time, this research can be extended to conducting post-detection etiologic investigations utilizing exposure information in the medical record.

The objective of this study was to validate two programs (SUPERSAT and EQUIL 2) for calculation of calcium oxalate (CaOx) and magnesium ammonium phosphate (struvite; MAP) relative supersaturation (RSS) in dog and cat urine. Healthy adult cats (n = 10) and dogs (n = 9) were fed standard diets for a 3-wk period. Urine was collected (24 h, dogs; 48 h, cats) and filtered, and the pH was measured. A 20-mL aliquot was titrated to pH 2 and frozen for analysis. Additional aliquots were incubated with 1 g seed crystals at 38[degree]C; CaOx for 24 h (cat) and 2, 6 and 9 d (dog); MAP for 48 h (dog) and 6 d (cat). Samples were analyzed for 10 substances. RSS was calculated using EQUIL 2 and SUPERSAT. CaOx RSS (SUPERSAT): dog urine was initially supersaturated, whereas cat urine was undersaturated with the diets used. Cat urine reached the solubility product (K[sub.sp]), (RSS = 1) after 24-h incubation, whereas dog urine was still approaching K[sub.sp] at 9 d. MAP RSS (SUPERSAT): urine from both species was undersaturated and increased toward K[sub.sp] during incubation. Final RSS values were compared for both programs. SUPERSAT resulted in values close to 1 for both CaOx and MAP; EQUIL 2 gave similar values for CaOx RSS, although MAP RSS values were considerably higher than 1. In conclusion, EQUIL 2 and SUPERSAT both calculated reasonably accurate RSS values for CaOx, whereas only SUPERSAT provided an accurate measure of MAP RSS. Key Words: * urine * cat * dog * supersaturation * computer program

Because dietary ingredients and feeding patterns influence the volume, pH and solute concentration of urine, diet can contribute to the etiology, management or prevention of recurrence of some causes of lower urinary tract disease. Most research assessing the effect of diet has focused on the latter two aspects, primarily because of interest in struvite urolithiasis. Manipulation of urine pH through dietary means has proven an effective tool for the management and prevention of struvite urolithiasis; acidification of urine, however, may be a risk factor for calcium oxalate urolithiasis, which now appears to occur with approximately equal frequency in cats. Prediction of urine pH from dietary analysis would thus be a valuable tool, but considerable further research is required before this can be achieved with commercial canned foods. With the growing importance of urolith types other than struvite, alternatives to the measurement of urine pH are required to assess critically the likely beneficial (or detrimental) effects of manipulation of nutrient profile. Measurement of urinary saturation may permit the development and fine tuning of nutrient profiles aimed at controlling lower urinary tract diseases in cats that are associated with a range of different mineral types. The majority of cats with signs of lower urinary tract disease do not, however, have urolithiasis; indeed, no specific cause can be established in most of these cats. Recent observations suggest that recurrence rates of signs in cats classified as having idiopathic lower urinary tract disease may be more than halved if affected animals are maintained on high, rather than low moisture content diets. KEY WORDS: * cats * lower urinary tract diseases * urine volume * urine pH * urinary saturation

A commercial diet with restricted levels of protein and phosphorus is tested for its effectivity in the management of feline renal disease. In the experimental design, cats with with renal failure were assigned to two groups. The treatment group was given a commercial restricted protein and phosphorus diet while the control group was fed diets with normal levels of protein and phosphorus. The results showed slower clinical deterioriation in cats fed with the restricted diet.

The clinical manifestations of food sensitivity reported in cats are mainly dermatologic, namely, pruritus, miliary dermatitis, facial dermatitis, erythema and eosinophilic lesions (Carlotti et al. 1990, White and Sequoia 1989). However, food sensitivity is only one of a number of possible causes of these signs. The reported prevalence of food sensitivity varies from 1% (Walton 1967) to 11% (Scott 1987) of all feline dermatoses. No age, breed or sex predilections have been noted. In addition to dermatologic signs, gastrointestinal (GI) disease has also been reported occasionally in association with food sensitivity (Nelson et al. 1984, Stogdale et al. 1982, Walton et al. 1968). Rarely, there may be respiratory and neurological involvement (Scott 1980). There have been few relatively large-scale studies of the causes of dietary sensitivity in cats. In those that have been conducted, beef, dairy products and fish have been the foods most commonly found to be responsible (Walton 1967, White and Sequoia 1989). The objectives of this study were to determine the prevalence of food sensitivity in cats with pruritus, chronic vomiting or diarrhea, and to identify the foods, food components or food additives responsible for the sensitivities. Materials and methods. A total of 128 cats presented to the Massey University Small Animal Clinic with the primary complaints of pruritus (n = 61), chronic vomiting (n = 29), diarrhea (n = 26), or concurrent pruritus and vomiting or diarrhea (n = 12) were entered into the study. The cats underwent standardized diagnostic protocols including the following: Dermatologic cases. Cats underwent clinical examination, microscopy of coat brushings, fungal culture and a flea treatment plan including weekly spraying with a product containing methoprene, pyrethrins, piperonyl butoxide and N-octyl bicycloheptane (Vet-Kern Ovitrol, Bayer, Auckland, New Zealand). Cats without a diagnosis then underwent an elimination diet trial using a commercial canned diet with protein sources limited to chicken and rice (Whiskas[R] Feline Selected Protein Diet, Masterfoods, Bruck, Austria) or venison and rice (Waltham[TM] Veterinary Diet Feline Selected Protein, Effem Foods, Bolton, Canada). The latter diet was selected only if the cat had received chicken in the previous 6 mo. The diet trial was conducted for a minimum of 4 wk; cats whose signs resolved were then rechallenged with their original diets. If signs recurred, the cat was again given the elimination diet for 2-4 wk until signs resolved. Resolution of signs on this second occasion was considered diagnostic of food sensitivity. Oral challenge tests were then conducted to try to identify the offending food item or additive. GI cases. Cats underwent clinical examination, fecal examination, hematology and biochemistry profiling, urinalysis, gastroduodenoscopy and biopsy, and colon biopsy. Breath hydrogen test, duodenal aspiration and quantitative culture were also conducted in diarrhea cases; abdominal radiography was conducted in vomiting cases. If no cause was apparent for the signs, an elimination diet trial was conducted as described above. Cats considered food sensitive then entered the oral challenge phase. Oral challenge studies were conducted with a group of additives (colors, preservatives and gums) and approximately five individual food proteins (selected on the basis of dietary history). The protein sources and food additives were fed for a minimum of four consecutive days followed by a 3-d washout period. Most cats were hospitalized for the oral challenge studies to allow close observation of their clinical signs. Their degree of pruritus was assessed by viewing videotapes of the cats behavior after being fed the challenge food. Repeat challenge was conducted with any item causing an equivocal adverse response, to confirm its effect. Results. Twenty-two (17%) of the 128 cats recruited to the study were confirmed as food sensitive (Table 1). Responsible foods included dry foods (n = 6), canned foods (n = 4), beef (n = 5), lamb (n = 3), chicken (n = 1), milk (n = 1), fish (n = 1), viscera (n = 2), gluten (n = 1) and food additives (n = 1) [ILLUSTRATION FOR FIGURE 1 OMITTED]. Two of these sensitivities were transient. These were confirmed according to the diagnostic criteria listed above, but were found to resolve spontaneously over 2-3 mo. A relatively high number of additional cats (n = 16) went into remission while consuming the canned diet, but did not recrudesce on challenge with their original diet. Data from these cats are not included with those confirmed as food sensitive. Discussion. This study confirmed that food sensitivity was a cause of clinical signs in 17% of this group of cats. This was a relatively high prevalence compared with some but not all previous reports of the condition in cats (O'Dair et al. 1996, Rosser 1993, Scott 1987, Walton 1967, White and Sequoia 1989). Close evaluation of North American studies that incorporated rechallenge revealed only 14 cases in 5 y drawn from three referral populations (White and Sequoia 1989), and 13 cases in 4 y from a referral hospital (Rosser 1993), an average of about three cases per year; a recent European study reported that in none of 20 cats were signs suggestive of allergic skin disease considered to be primarily associated with food hypersensitivity (O'Dair et al. 1996). The high prevalence of food sensitivity in the group of cats in this study compared with that of some other studies suggests that there are regional variations in the prevalence of food sensitivity. Alternatively, the high prevalence may represent more rigorous diagnostic effort or selection bias by the veterinarians that referred the cats for the study. The reasons why a high number of cats went into remission on the elimination diet but did not show recrudescence when exposed to their original diet are unknown. Possible explanations include failure to identify the food to which they were allergic, inadequate time for the recurrence of signs, spontaneous resolution of their underlying condition or, for cats with skin disease, concurrent elimination of other allergens (e.g. fleas, inhaled allergens) that contributed subclinically to pruritus (the 'allergy threshold'). Whatever the reasons, these results emphasize the need for rechallenge to confirm the diagnosis of food sensitivity. The foods to which the cats were sensitive are of interest. Sequential challenges of the cat sensitive to gluten confirmed that this individual showed adverse responses to wheat, barley and gluten flour, but not to maize gluten (maize gluten is antigenically dissimilar to wheat gluten). The study indicates that additives were not a significant cause of dietary sensitivity in this group of cats. The one cat sensitive to additives appeared to respond adversely only to a mixture of compounds, and not to any single component. The observation that lamb was second in importance to beef as an individual food item responsible for sensitivity was perhaps not surprising, given that sheep meat is a common diet for cats in New Zealand. In conclusion, food sensitivity was a significant cause of chronic dermatologic and gastroenteric complaints in this group of cats. Cats with concurrent pruritus and vomiting or diarrhea had the highest prevalence of food sensitivity. Rechallenge with the cat's original diet is essential to confirm a diagnosis of food sensitivity. KEY WORDS: cats; food sensitivity; pruritus; diarrhea; vomiting

Acidification of urine through dietary modification is considered to be the cornerstone for the management and prevention of struvite (magnesium ammonium phosphate) urolithiasis in cats (Taton et al. 1984). Urinary acidification, however, may be a risk factor for calcium oxalate urolithiaisis (Kirk et al. 1995, Osborne et al. 1995). The aim of this study was to compare the effect of commercial dry cat foods on urinary pH, and struvite and calcium oxalate relative supersaturation (RSS), the ultimate determinant of crystallization. Materials and methods. Nine different dry cat foods were fed to groups of six healthy, adult domestic short-haired cats 29 neutered females and 25 neutered males) for periods of between 14 and 21 d. Food allowances were calculated on the basis of an assumed maintenance requirement of 250 kJ/(kg body weight [multiplied by] d); the daily allowance was fed as two meals at 0800 and 1530 h. The cats were housed individually throughout each trial. All housing conditions and procedures fell within the UK Home Office regulations. During the last week of each trial, a 48-hour urine collection was made over dry ice to ensure rapid freezing of the samples. At the end of the collection period, the samples were thawed, and volume and pH were measured. The samples were acidified to pH 2 with hydrochloric acid and frozen for further analysis. Urine concentrations of sodium, potassium, magnesium, calcium, chloride, sulfate, phosphate, oxalate, citrate, pyrophosphate, ammonium and uric acid were analyzed by HPLC. A computer program, Equil 2 (Werness et al. 1985), was used to calculate urinary RSS for struvite and calcium oxalate from the concentrations of these analytes. This resulted in one struvite and one calcium oxalate RSS value for each cat during each trial. RSS is calculated from the activity product of the sample divided by the solubility product for the crystal in question; thus, values of KEY WORDS: cats, feline, urine pH, relative supersaturation, dry cat food

Urolithiasis, with or without urinary tract infection, is an important cause of lower urinary tract disease in dogs. Research has focused on gaining understanding of the factors that could either contribute toward urolith formation or be of value in the management of clinical cases associated with their presence. Work in this area has focused on the influences of urinary tract infection and the effects of dietary minerals, water turnover and urinary pH. A noninvasive system has been established at the Waltham Centre for Pet Nutrition to monitor various aspects of canine urinary tract health. A similar feline system has previously been described (Markwell and Smith 1993). Materials and methods. Dogs were individually housed in an environmentally controlled two-room pen consisting of an inner room (3.75 [m.sup.2]) entered from a central corridor and an outer room (2 [m.sup.2]). The floor covering in the inner room was heat-sealed sheet vinyl extending 40 cm up the walls; the outer room consisted of a fiberglass tray. A section of each inner pen had an underfloor warm bed area heated by electric cable. There was a separate air supply and extract for each pen with 12 air changes per hour. Warm air was supplied to the inner room and extracted from the outer conservatory. The temperature of the inner room was maintained at 22 [+ or -] 2 [degrees] C. In this study, a dry feline clinical diet (Waltham Veterinary Diet Feline Control pHormula, Effem Foods, Bolton, Cananda), designed for the treatment of struvite-associated urolithiasis, was fed to a panel of six dogs (one Labrador retriever, neutered female, age 5.8 y; two miniature schnauzers, one neutered male, one entire male, mean age 3.7 [+ or -] 0.1 y; three beagles, two neutered females, one neutered male, mean age 9.8 [+ or -] 2.5 y) for 42 d. The dogs were fed individually, to adult maintenance energy requirements (calculated as 460 body [weight.sup.0.75] kJ/d), three times daily at 0830, 1130 and 1530 h, and had free access to water. Blood samples were collected at the end of the study to assess the risk of metabolic acidosis. All housing conditions and procedures fell within the UK Home Office regulations. Urine samples were obtained by training dogs to urinate in the fiberglass tray. The urine rapidly drained into a glass U-tube that housed a combined pH and temperature electrode attached to a pH meter. The computer software (Signal Centre, Computer Park Software, Kettering, Northants, UK) recorded urine pH and temperature data from each pH meter every 30 s. Every 24 h, the data were analyzed by the software, which identifies urinations by an increase in the temperature of urine in the U-tube of at least 2 [degrees] C above ambient temperature. The software program was also designed to indicate freshly voided samples by auditory and visual means, allowing immediate sample collection when microscopic examination was required. The collection system can also be modified to freeze urine on voiding. Samples collected in this manner over a 48-h period are then defrosted, titrated to pH 2 with hydrochloric acid and analyzed for sodium, potassium, magnesium and calcium, chloride, sulfate, phosphate, oxalate, citrate, pyrophosphate, ammonia, uric acid and creatinine by HPLC. Urinary relative supersaturation (activity product/solubility product) for four urolith types are then calculated by computer program (Equil 89D, University of Florida, Gainesville, FL). A urinary relative supersaturation value of 1.0 indicates that the urine is oversaturated with respect to that urolith type. Results. Individual mean urine pH values in the dogs were all KEY WORDS: dogs, canine, urine pH, saturation, urinary tract health

Nutrient intake and urine composition were analyzed in calcium oxalate (CaOx)stone-forming and healthy control dogs to identify factors that contribute to CaOx urolithiasis. Stone-forming dogs had significantly lower intake of sodium, calcium, potassium, and phosphorus and significantly higher urinary calcium and oxalate concentrations, calcium excretion, and CaOx relative supersaturation (RSS). Feeding a diet used in the treatment of canine lower urinary tract disease for 1 month was associated with increased intake of moisture, sodium, and fat; reduced intake of potassium and calcium; and decreased urinary calcium and oxalate concentrations, calcium excretion, and CaOx RSS. No clinical signs of disease recurrence were observed in the stone-forming dogs when the diet was fed for an additional 11 months. The results suggest that hypercalciuria and hyperoxaluria contribute to the formation of CaOx uroliths in dogs and show that dietary modifications can alter this process.