An apparatus for making fine-grained measurements of canine eating behavior

Canine Food Preference Assessment of Animal and Vegetable Ingredient-Based Diets Using Single-Pan Tests and Behavioral Observation

Knowledge of canine food selection is critical for both the pet food industry and dog owners, since owners want quality foods that are palatable, while fulfilling their pet's nutritional requirements. There are two common methods for assessing canine food preference: the two-pan test and the one-pan test. Neither test fully accounts for the complexity of the canine feeding experience nor do they provide applicable representations of canine feeding behavior in the home. The objectives of this study were to (1) determine whether dogs display a preference for animal ingredient-based diets when compared with vegetable ingredient-based diets and (2) examine whether dogs experience neophobia when presented with a novel diet. Eight adult Beagles (average age = 24 months, weighing 8-12 kg) were individually fed each of four novel diets in a 4 × 4 replicated Latin square design, with 10-d treatment periods and four dietary treatments. Data were analyzed using a mixed model with repeated measures and significance was declared when p < 0.05. The diets were: animal and vegetable ingredient-based diets, and animal- and vegetable-based ingredients diluted with anhydrous α-d-glucose. The diluted diets were used for a larger study to determine true mineral digestibility. Dogs were fed twice per day (0800 and 1300 h). Behavioral observations were made by video on the first, and last 2 days of each 10-day treatment period of both a.m. and p.m. feedings. Time to consume feed, distraction, hesitation, level of anticipation pre-consumption, and interest post-consumption were recorded. Dogs experienced initial disruptive (neophobic) effects of a novel diet. Neophobia was demonstrated by a decreased (slower) rate of consumption, increased distraction during consumption of the diet, and increased hesitation on the first day of each new diet (p < 0.05). The level of interest post-consumption was highest when dogs consumed the animal-based ingredients diet (p < 0.05). This study presents insights into canine food preference assessment methods that may more accurately represent the dog owner's experience. Further research is required to determine the minimum length of time necessary to eliminate neophobia to food. In addition, future research should also aim to establish whether interest post-consumption is due primarily to food preference or acute satiety.

Ingestive behavior and body temperature of pigeons during long-term cold exposure

Pigeons well adapted to living in 21 degrees C ambient temperature (T(a)) were continuously exposed to cold T(a) for 6 days (Experiment 1) or 30 days (Experiment 2). The pigeons lived on a 12:12 L:D cycle where they could obtain short access to food and water at any time in the light phase by making 12 keypeck responses. Across the two experiments, the levels of cold exposure were 6 degrees C, 1 degrees C, and 0.6 degrees C. In cold, total daily food intake increased gradually across the first few days of the exposure, and the new level of food intake was inversely related to T(a). The daily ratio of total water drunk to total food eaten averaged approximately 1.3 in 21 degrees C, fell to approximately 1.0 on day 1 of cold exposure, and remained at that level for as long as 30 days. The day-night cycle in core body temperature was not changed by cold exposure. The bimodal temporal pattern of feeding in the light phase, which is characteristic of pigeons in moderate T(a), was preserved in the cold although the absolute level of feeding activity was enhanced. An analysis of the ways individual pigeons achieved total daily food intake by combining a number of feeding episodes with an average amount eaten per episode revealed considerable variation between birds, but a relatively constant feeding style within bird over time. In the colder temperatures used, however, the pigeons all increased the number of feeding episodes per day. The results provide the first detailed analysis of cold-induced changes in ingestive behavior in the pigeon and raise several questions about the behavioral expression of cold-sensitive regulatory processes.

Operant conditioning methodology in the assessment of food preferences: introductory comments

This paper provides a general introduction to the methodology used in the next three papers of this monograph to test dogs' food preferences. This "operant conditioning" methodology was developed in behavioral laboratories concerned with learning in animals. The logic of the methodology is described, some technical and practical aspects of the methodology are summarized, and its application in the hedonic-scaling of qualitatively different foods is discussed. The relation between this new methodology and the traditional two-bowl preference test is reviewed.

Studies in canine olfaction, taste and feeding: a summing up and some comments on the academic-industrial relationship

The authors discuss two principal points. First, what appear to be contradictory findings in the feeding studies in this monograph can be resolved by clarifying two terms: palatability and preference. Second, some of the work in the monograph resulted from an academic and industrial relationship. This relationship was judged mutually beneficial and productive. The primary benefits are discussed along with what are considered the key ingredients for a successful joint venture.

Twenty-four-hour free-feeding patterns of dogs eating dry food

In order to provide some detailed information on the feeding behavior of freely-feeding dogs, four adult beagles were maintained in an isolated outdoor environment where food and water were freely available. Observations across an 8-month period indicated that the dogs are episodically (in "meals") and that the total daily intake of food and water changed as the observation period progressed, most likely as a consequence of change in the ambient environmental conditions across seasons. Within-day changes in ambient temperature, and the timing of daily maintenance activities in the animal's runs influenced the temporal distribution of meals with the day.

Fine-grained measures of dogs' eating behavior in single-pan and two-pan tests

The feeding behavior of dogs in one-pan and two-pan tests was measured in the usual way (total food intake in the test) and at a fine-grained level (cumulative amount eaten on a moment-by-moment basis during the test). The four experiments reported studied dogs' reactions to different dry foods, and to semi-moist and canned foods. The fine-grained measures were informative about the dogs' reactions to the foods in several ways that could not be derived from the usual intake measure. The main value of the fine-grained measurements seems to be that they suggest new directions for research on feeding behavior that may improve the understanding of performance in one- and two-pan tests.