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Abstract

Objective

To validate equations predicting body composition of dogs, using deuterium oxide dilution.

Animals

38 female and 37 male dogs selected by defined body weight and body condition criteria.

Procedure

Measured equilibrated deuterium concentration in serum after IV administration of isotope was used to determine isotope space and predict body water, fat, nitrogen, and ash contents determined from analysis of homogenized carcass. Equations predicting body composition were derived, using regression analysis, and were validated, using data-splitting techniques.

Results

Deuterium space (in kilograms) overestimated kilograms of body water content by mean 21.8% ± SD of 4.18%. Regression equations were derived and validated to predict kilograms of body water and ash from kilograms of deuterium space, and proportions of body water, fat, nitrogen, and ash from proportion of deuterium space. Coefficients of determination (r 2) and means of standard errors of estimating new values (SEE) were, respectively, 0.993 and 0.4 kg for body water content, and 0.942 and 0.08 kg for ash content. For proportions, SEE were 2.0, 2.7, 0.1, and 0.4% for body water, fat, nitrogen, and ash, respectively. Two factors, time for isotope equilibration and whether samples were processed by vacuum sublimation, improved SEE for proportion of body water from 2.0 to 1.3% and of fat from 2.7 to 1.8%. Equations predicting absolute quantities of fat and nitrogen could be derived but not validated.

Conclusions

Deuterium dilution can be used to predict body composition of dogs with precision equal to that determined for other species. (Am J Vet Res 1998;59:927–937)

Free access
in American Journal of Veterinary Research

Summary

Fifteen 2-week-old kittens were randomly assigned to 1 of 3 milk treatment groups as the sole source of nutrition for 4 weeks: queen's milk, commercially available kitten milk replacer (cmr), and an experimental milk replacer (exp). Kittens fed queen's milk suckled ad libitum, whereas cmr- and exp-fed kittens were tube-fed every 6 hours. Kittens were weaned at 6 weeks of age and were fed a feline growth diet ad libitum for an additional 4 weeks. Kittens were examined at 2, 4, 6, 8 and 10 weeks of age; the procedure included an ophthalmic examination and blood sample collection for cbc and serum biochemical and amino acid analyses. Kittens fed cmr and exp diets had weight gain greater than that for queen's milk-fed kittens. The kittens fed cmr, however, had diarrhea throughout most of the milk-feeding trial and developed diffuse anterior and posterior lens opacification and vacuolation at the posterior Y-sutures. The lens opacities noticed in the kittens during the milk treatments resolved to a residual perinuclear halo, and a few incipient cortical opacities were observed by the end of the growth diet-feeding period. Serum arginine concentration was significantly (P ≤ 0.05) lower in the cmr-fed kittens, but was not different during the growth diet-feeding period. We concluded that the exp diet supported normal growth in 2- to 6-week-old kittens; cmr supported normal kitten growth rate, but resulted in diarrhea and cataract formation; and serum amino acid data indicated that low arginine concentration may have been related to the cmr-induced cataract formation.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To measure the ascorbic acid (AA) concentration in bronchoalveolar lavage fluid (BALF) and cellular glutathione peroxidase (cGPx) activity in RBCs and WBCs from peripherally obtained blood and in cells from BALF to determine whether differences existed between the 2 major redox systems in recurrent airway obstruction (RAO)-affected and -nonaffected (control) horses and between systemic and local pulmonary responses in the glutathione redox system.

Animals—16 adult horses in pairs: 8 healthy (control) and 8 RAO-affected horses.

Procedures—Physical examination data and biological samples were collected from horses before (remission), during, and after (recovery) environmental challenge with dusty straw and hay. At each stage, BALF cell AA concentration and RBC, WBC, and BALF cell cGPx activity were measured.

Results—Compared with control horses, RAO-affected horses had significantly higher cGPx activity in RBCs at all points and in WBCs during remission and challenge. The BALF cell cGPx activity was higher in RAO-affected horses during recovery than during remission The BALF cell AA concentration did not differ significantly in control horses at any point, but total and free AA concentrations were significantly lower in RAO-affected horses during the challenge period than during remission and recovery periods.

Conclusions and Clinical Relevance—High cGPx activity suggested this redox system was upregulated during exposure to dusty straw and hay to combat oxidative stress, as AA was depleted in RAO-affected horses. The relative delay and lack of comparative increase in cGPx activity within the local environment (represented by BALF cells), compared with that in RBCs and WBCs, might contribute to disease in RAO-affected horses.

Full access
in American Journal of Veterinary Research

SUMMARY

Effects of selenium (Se) deficiency and supplementation on production of colostral immunoglobulins by beef cows and transfer of antigen-specific and nonspecific immunoglobulins to their calves were examined. Eighty beef cows, with marginal to deficient Se status (blood Se concentration, 50 μg/L), were allotted by breed and age to 1 of 4 Se treatment groups (n = 20/group): no supplemental Se; parenteral administration of 0.1 mg of Se and 1 mg of vitamin E/kg of body weight; ad libitum consumption of 120 mg of Se/kg of salt-mineral mix (smm); and parenteral administration of 0.1 mg of Se and 1 mg of vitamin E/kg plus ad libitum consumption of 120 mg of Se/kg of smm. All cows were inoculated IM with lysozyme. Cows consumed Se-deficient pastures or hay (21 to 62 μg/kg) during the study that began at mid-gestation and ended at postpartum hour 24. Although the concentration of specific lysozyme antibodies was not affected, cows given 120 mg of Se/kg of smm (treatments 3 and 4) had higher colostral IgG concentration (P < 0.002) than did Se-deficient cows (treatments 1 and 2). Calves from cows in treatments 3 and 4 had higher postsuckle serum concentrations of IgG (P < 0.01) than did calves from cows in treatments 1 and 2. Colostral IgM and calf serum IgM concentrations did not differ among treatments.

Free access
in American Journal of Veterinary Research

Summary

Eighty gestating beef cattle were used to determine the effect of trace mineral salt mixtures containing copper (Cu) and iron (Fe) on selected immune functions and factors affecting copper bioavailability. Pastured cattle were randomly assigned to receive one of the following combinations of Cu and Fe in the free-choice trace mineral salt: (1) 0 mg of Cu/0 mg of Fe/kg of trace mineral salt, (2) 1,600 mg of Cu (CuSO4)/3,000 mg of Fe/kg of trace mineral salt, (3) 1,600 mg of Cu (CuSO4)/0 mg of Fe/kg of trace mineral salt, and (4) 1,600 mg of Cu (CuCO3)/3,000 mg of Fe/kg of trace mineral salt. Total Cu/Fe consumption (from trace mineral salt) was 2/678, 193/1,050, 162/553, and 202/1,140 mg/head/d, respectively, for the 4 groups. After a 1-month period of acclimation and also on day 28 of the 36-day study, copper concentrations in serum were significantly (P < 0.05) lower in group 1 than in groups 3 and 4. Serum copper concentrations did not increase with time for any group, whereas hepatic copper concentrations increased significantly (P < 0.05) with time for all groups except group 1. Hepatic iron concentrations were similar among groups at the time of the initial and final hepatic biopsies on days 0 and 28, respectively. Hepatic iron concentrations increased significantly (P < 0.05) with time in groups 3 and 4.

Humoral response to chicken γ-globulin was high but did not differ among groups on any of the days analyzed. Neutrophil function tests, consisting of hydrogen peroxide production, phagocytosis of latex particles, calcium uptake, and superoxide production, were different only for phagocytosis among groups; the percentage of neutrophils phagocytizing latex beads was significantly (P < 0.05) lower for group 2 than the other groups. A similar reduction in phagocytosis was prevented by the omission of additional Fe from the trace mineral salt (groups 1 and 3) or use of CuCO3 (group 4).

Free access
in Journal of the American Veterinary Medical Association

SUMMARY

Two digital oscillometric human blood pressure measuring devices were modified and evaluated as blood pressure monitors in 12 healthy anesthetized dogs. Direct arterial pressures were measured via cannulation of the dorsal pedal artery and were correlated with indirect measurements through an inflatable cuff placed over the dorsal pedal artery below the hock joint of the contralateral limb. Direct and indirect measurements were compared for systolic, diastolic, and calculated mean arterial pressures. Blood pressure ranges between 215/145 mm of Hg and 65/30 mm of Hg were obtained, using combinations of halothane, phenylephrine, calcium, and iv administered fluids. Machine A was found to be insufficient for clinical application, on the basis of correlation coefficients between direct and indirect pressures of 0.78, 0.65, and 0.74 for systolic, diastolic, and mean arterial pressures, respectively. Higher correlation coefficients between direct and indirect pressures (0.77, 0.87, and 0.87, respectively) were obtained with machine B. The results of the study reported here suggest machine B may be an effective blood pressure monitoring device in anesthetized dogs.

Free access
in American Journal of Veterinary Research

Abstract

Objective—To evaluate the phospholipid composition and function of surfactant in horses with recurrent airway obstruction (RAO) at various clinical stages and compare these properties with findings in horses without RAO.

Animals—7 horses with confirmed RAO and 7 without RAO (non-RAO horses).

Procedures—Pairs of RAO-affected and non-RAO horses were evaluated before, during, and after exposure to hay. Evaluations included clinical scoring, lung function testing, airway endoscopy, and bronchoalveolar lavage fluid (BALF) absolute and differential cell counts. Cell-free BALF was separated into crude surfactant pellet and supernatant by ultracentrifugation, and phospholipid and protein concentrations were determined. Phospholipid composition of crude surfactant pellets and surface tension were evaluated with high-performance liquid chromatography and a pulsating bubble surfactometer, respectively. Findings were compared statistically via mixed-effects, repeated-measures ANOVA.

Results—Total phospholipid concentration in BALF was lower in RAO-affected versus non-RAO horses at all sample collection times. In the RAO-affected group, total phospholipid concentration was lower during exposure to hay than before or after exposure. There were no significant differences in BALF protein concentration, percentages of phospholipid classes, or surface tension between or within groups of horses.

Conclusions and Clinical Relevance—All clinical stages of RAO-affected horses were characterized by low surfactant concentration in BALF. Exacerbation of RAO led to an additional decrease in surfactant concentration. Causes for low surfactant concentration in RAO-affected horses remain to be determined. Low phospholipid concentration may render RAO-affected horses more susceptible than unaffected horses to surfactant alterations and contribute to clinical disease status and progression.

Full access
in American Journal of Veterinary Research