Procedure—Soy isoflavone content of each food was
determined by use of acid-methanol hydrolysis and
high-pressure liquid chromatography with ultraviolet
absorbance detection. Isoflavones were identified
and quantified by reference to authentic standards.
Results—Genistein and daidzein were the major soy
isoflavones identified in 24 of 42 foods, with concentrations
ranging from 1 to 163 µg/g of food. Foods
labeled as containing soybean solids (16/42) had
isoflavone concentrations > 11 µg/g. More dry (13/14)
and semimoist (6/6) foods contained isoflavones than
moist foods (5/22). Isoflavone content and food cost
were negatively correlated for dry and semimoist
foods but not for moist foods. Total amount of
isoflavone consumed by cats fed these soy-containing
foods as a sole maintenance diet was estimated
to be between 0.6 and 4.5 mg/kg of body weight/d,
which is comparable to concentrations in humans that
result in a measurable although modest effect on
serum concentrations of steroid and thyroid hormones.
Conclusions and Clinical Relevance—Genistein and
daidzein are common constituents of commercial cat
foods. Predictors of isoflavone content included ingredient
labeling, food type, and food cost. Soy
isoflavones in some commercial cat foods were
detected in amounts predicted to have a biological
effect. (Am J Vet Res 2002;63:181–185)
Objective—To determine range of calorie density and feeding directions for commercially available diets designed for weight management in dogs and cats.
Sample Population—93 diets (44 canine diets and 49 feline diets) that had a weight management claim with feeding directions for weight loss or implied weight management claims.
Procedures—Calorie density was collected from product labels or by contacting manufacturers. Recommended feeding directions for weight loss were compared with resting energy requirement (RER) for current body weight by use of a standard body weight (36.4 kg [80 lb] for canine diets and 5.5 kg [12 lb] for feline diets).
Results—Calorie density for the 44 canine diets ranged from 217 to 440 kcal/cup (median, 301 kcal/cup) and from 189 to 398 kcal/can (median, 310 kcal/can) for dry and canned diets, respectively. Calorie density for the 49 feline diets ranged from 235 to 480 kcal/cup (median, 342 kcal/cup) and from 78 to 172 kcal/can (median, 146 kcal/can) for dry and canned diets, respectively. Recommended calorie intake for weight loss in dogs ranged from 0.73 to 1.47 × RER (median, 1.00 × RER) and for weight loss in cats ranged from 0.67 to 1.55 × RER (median, 1.00 × RER). Diets ranged from $0.04 to $1.11/100 kcal of diet (median, $0.15/100 kcal of diet).
Conclusions and Clinical Relevance—Wide variation existed in recommended calorie intake, kilocalories, and cost for diets marketed for weight loss in pets. This variability could contribute to challenges of achieving successful weight loss in pets.
Objective—To determine the proportion of dog breeders who fed diets meeting the Association of American Feed Control Officials regulations for nutritional adequacy for reproduction and growth and to investigate factors that influenced feeding practices of breeders.
Design—Web-based cross-sectional survey.
Sample—2,067 dog breeders from the United States and Canada.
Procedures—A self-administered, anonymous, Web-based questionnaire was used to collect information on breeder demographics and feeding practices during 3 life stages of dogs: adult maintenance for nonpregnant dogs, gestation-lactation, and puppy growth. Appropriateness of commercial diets for each life stage was determined by respondent-reported nutritional adequacy statements on product labels. Data were also collected regarding breeder criteria for diet selection and sources of nutrition information.
Results—A substantial number of breeders reported feeding commercial diets not intended for that life stage during gestation-lactation (126/746 [16.9%]) and puppy growth (57/652 [8.7%]). Additionally, approximately one-seventh of breeders reported feeding home-prepared diets for ≥ 1 life stage. Unsubstantiated health and marketing information influenced diet selection of many breeders. Veterinarians, although generally viewed as a trusted source of nutrition information, were consulted by only 823 of 1,669 (49.3%) breeders and were viewed less favorably by breeders feeding home-prepared diets, compared with the opinion of breeders feeding commercial diets.
Conclusions and Clinical Relevance—Veterinarians should consider taking a more proactive role in directing dog breeders and other pet owners toward scientifically substantiated sources of diet information and in explaining the importance of current nutritional standards for reproduction and early development of dogs.
Objective—To measure thiamine concentrations in commercial canned foods formulated for cats as an initial assessment of the variation among canned foods and to determine the effects of flavor (fish vs nonfish) of the food, texture (paté vs nonpaté) of the food, country of manufacture, and size of the company on thiamine concentration.
Design—Prospective cross-sectional study.
Sample—90 canned, nontherapeutic diets formulated for cats (1 fish and 1 nonfish flavor for each of 45 brands).
Procedures—Each canned food was homogenized, and thiamine concentration was analyzed with a fluorometric method.
Results—Thiamine concentration was below the minimums of the Association of American Feed Control Officials in 12 of 90 (13.3%) foods and below the recommended allowance of the National Research Council in 14 of 90 (15.6%) foods. Paté foods had significantly lower thiamine concentrations than did nonpaté foods, and foods from smaller companies had significantly lower thiamine concentrations, compared with concentrations in foods from larger companies. Flavor of food and country of manufacture were not significantly associated with thiamine concentration.
Conclusions and Clinical Relevance—A wide range of thiamine concentrations was found in the foods evaluated. Thiamine concentration in a substantial percentage of commercially available canned foods was below the amount recommended for adult cats. Additional research on interlot and intralot variation in thiamine concentrations of foods formulated for cats is warranted. Companies should implement strict quality control and analysis practices regarding food products. Clinicians should consider thiamine deficiency as a differential diagnosis in a cat with acute neurologic dysfunction.
Objective—To determine plasma malondialdehyde
(MDA) and serum vitamin E concentrations in dogs
with immune-mediated hemolytic anemia (IMHA) and
healthy control dogs.
Sample Population—Serum and plasma samples
from 36 dogs with IMHA and 40 healthy control dogs.
Procedure—Blood samples were collected from all
study dogs. Plasma MDA concentrations were measured
by use of a commercial colorimetric assay, and
serum vitamin E concentrations (α-, γ-, and δ-tocopherol
concentrations) were measured via high-performance
Results—Plasma MDA concentrations were significantly
higher in the dogs with IMHA than in the control
dogs. Compared with control dogs, serum α-, γ-,
and δ-tocopherol concentrations were significantly
lower in the IMHA-affected dogs.
Conclusions and Clinical Relevance—Results indicated
a state of oxidative stress and reduced antioxidant
reserve in dogs with IMHA; this finding provides
support for further investigation of the potential benefits
of antioxidant treatment in dogs with this disease.
(Am J Vet Res 2004;65:1621–1624)
Objective—To compare morphometric measurements and serum insulin-like growth factor (IGF-1) concentration in cats with and without hypertrophic cardiomyopathy (HCM), and assess the hypothesis that cats with HCM have larger body size and skeletal features and higher serum IGF-1 concentrations than healthy cats.
Animals—25 cats with HCM and 22 healthy control cats.
Procedures—Physical examination and echocardiography were performed to classify cats into the HCM and control groups. Data collected from each cat included diet history, body weight, body condition score, lengths of the humerus and 4th and 12th thoracic vertebrae, heart size, head length and width, and abdominal circumferences. Comparisons of these variables were made between groups.
Results—Body condition score in HCM-affected and control cats did not differ significantly. However, median head width; lengths of the head, 4th and 12th thoracic vertebrae, and humerus; and body weight in the HCM-affected group were significantly greater than values in the control group. Median serum concentration of IGF-1 was not significantly different between groups.
Conclusions and Clinical Relevance—These data suggested that among the study cats, those with HCM were skeletally larger, but not more obese, than healthy cats. Whether this was attributable to differences in early growth or other causes requires additional investigation.