Development of a technique for the in vivo assessment of flatulence in dogs.

OBJECTIVE: To develop a noninvasive method for the in vivo assessment of flatulence in dogs. ANIMALS: 8 adult dogs. PROCEDURE: Rectal gases were collected via a perforated tube held close to each dog's anus and attached to a monitoring pump fitted with a sensor that recorded hydrogen sulfide concentrations every 20 seconds. Patterns of flatulence were monitored for 14 hours after feeding on 4 days, and within- and between-dog variation was assessed over 4 hours on 4 consecutive days. Rate of hydrogen sulfide production (flatulence index) and frequency and number of emissions were evaluated as potential indicators of flatus characteristics. An odor judge assigned an odor rating to each flatulence episode, and the relationship between that rating and hydrogen sulfide concentration was determined. RESULTS: Flatulence patterns varied within and between dogs. Variation was most pronounced for flatulence index; mean coefficients of variance within dogs over time and between dogs on each day were 75 and 103%, respectively. Flatus with hydrogen sulfide concentrations > 1 parts per million could be detected by the odor judge, and severity of malodor was highly correlated with hydrogen sulfide concentration. Odor ratings were accurately predicted by use of the equation 1.51 X hydrogen sulfide concentration(0.28). CONCLUSIONS AND CLINICAL RELEVANCE: The technique described in this report appears to provide sensitive, reliable, and relevant data and will enable further studies of the factors that influence flatulence in dogs. Use of this technique also has the potential to aid in investigations of colonic physiology and pathology.

Validation of the doubly-labelled water technique in the domestic dog (Canis familiaris).

We validated doubly-labelled water (DLW) by comparison to indirect calorimetry and food intake-mass balance in eight Labrador dogs (24-32 kg) over 4 d. We used several alternative equations for calculating CO2 production, based on the single- and two-pool models and used two alternative methods for evaluating the elimination constants: two-sample and multiple-sampling. In all cases the DLW technique overestimated the direct estimate of CO2 production. The greatest overestimates occurred with the single-pool model. Using two samples, rather than multiple samples, to derive the elimination constants produced slightly more discrepant results. Discrepancies greatly exceeded the measured analytical precision of the DLW estimates. The higher values with DLW probably occurred because the dogs were extremely active during the 1 h in each 24 spent outside the chamber. Estimates of CO2 production from food intake-mass balance, which include this activity, produced a much closer comparison to DLW (lowest mean discrepancy 0.3 % using the observed group mean dilution space ratio and an assumption that the mass changes reflected changes in hydration for all except one animal). We recommend an equilibration time of 6 h and use of the two-pool model based on the observed population dilution space for future studies of energy demands in dogs of this body mass.

The influence of lifestyle and diet on the lipoprotein profile of border collies.

Plasma lipoprotein cholesterol and triglycerides were determined in two groups of Border Collies, one actively working and the other pets. Baseline concentrations of total, low density lipoprotein (LDL) and high density lipoprotein (HDL) cholesterol were higher, and HDL triglyceride concentrations lower in the pet dogs. Lifestyle of the dogs was assessed by questionnaire completed by the owners. Measurement of exercise was made by visual observation and using a Caltrac activity monitor. The working dogs were a homogenous group with respect to lifestyle and diet, but the pet dogs showed differences in lipoprotein profile relating to housing, dietary fat and exercise intensity. Two diets with different levels of dietary fat (13 and 20 per cent dry weight) were given for two months each. After two months on either of the diets the cholesterol concentration of the working dogs increased and HDL triglyceride concentration decreased, and there were no significant differences between the groups, but very low density lipoprotein (VLDL) triglyceride increased significantly in the less active pet dogs.

The effect of dietary changes on plasma lipids and lipoproteins of six Labrador retrievers.

Six healthy, spayed female Labrador Retrievers (aged 5.5 to 11 years), kept under controlled conditions of exercise and housing, were fed a diet of 15 per cent fat, 24 per cent carbohydrate and 33 per cent protein for two weeks before and between each of three test diets, of differing fat to carbohydrate ratios (A 13:44, B 20:33, C 25:26 fat:carbohydrate gm per cent dry weight) given in a predetermined order for four weeks each. Fasting plasma lipoproteins and total fatty acids were measured weekly. In the fourth week of each test period post-prandial plasma lipoproteins were measured. Diets B and C increased total (P < 0.001) and LDL cholesterol (P < 0.05) whilst diet A increased HDL triglyceride (P < 0.05). Eicosapentaenoic acid (C20:5) increased on diets B and C, and oleic acid (C18:1) on diet A. Post-prandial hypertriglyceridaemia occurred on all diets. Chylomicron clearance was slower on higher fat diets. Relatively small dietary changes produced significant alterations of plasma lipids, lipoproteins and chylomicron clearance.