Energy-intake and activity risk factors for owner-perceived obesity in a defined population of Swedish dogs.

Our main objective was to obtain baseline data on daily metabolisable energy (ME) intake, activity, and risk factors for obesity in a population of 460 privately owned Swedish dogs in 1999. A previously validated mail-and-telephone questionnaire was used (Sallander et al., 2001a). The dogs were of 124 breeds, 1-3 years old, and had body weights (BW) between 1 and 75kg. The ME intakes of this population could be described with the equation ME(intake) (kilojoules, kJ/d)=554BW(0.66) (r(sp)=0.73, P=0.0001). The energy intake originating from commercial foods was 79% (median, range 45-97). Table foods generally had a higher fat content (median 13g/megajoule, MJ, range 1-122) than commercial foods (median 8g/MJ, range 2-18; P=0.0001). The median energy density was 1603kJ/100g (median; range 1106-2105). Almost all (97%) dogs were taken for walks, and there was a significant difference between the duration of the walks during weekdays and weekends (medians 60 and 90min/d, respectively, P=0.006). Sixty percent of all dogs were trained in activities such as obedience (31%), hunting (27%) or tracking (18%) for a median of 35min/d (range 1-146). The final regression model for obesity included the factors sex, appetite and feeding a home-made diet/table foods. Dogs that were perceived to have good or very good appetite had 3.42-fold greater odds for obesity than individuals with bad or very bad appetite (95% CI 1.19-9.80; P=0.022). Females had 2.17-fold greater odds of being obese than males did (95% CI 1.30-3.70; P=0.003). Also, dogs fed table foods or home-made diets had 2.06-fold greater odds of obesity than those that were not given these food items (95% CI 0.97-4.35; P=0.050).

Feeding patterns and dietary intake in a random sample of a Swedish population of insured-dogs.

We used a validated mail and telephone questionnaire to investigate baseline data on feeding patterns and dietary intake in a random sample of 460 Swedish dogs. In 1999, purebred individuals 1-3 years old in the largest insurance database of Sweden completed the study. Most dogs were fed restricted amounts twice a day, and the feeding patterns seldom were changed after the age of 6 months. Typically, the main constituent of the meals was dry food [representing 69% of dry matter (DM)]. Four out of five dogs also got foods that (in descending order of the amount of energy provided) consisted of vegetable oil, meat, sour milk, bread, potatoes, pasta, lard/tallow, sausage, cheese, rice and fish. The heavier the dog (kg), the more dry dog food was consumed (g DM/d). The dry-food intakes (g DM/d) increased linearly with body weight (BW, in kg): intake=-15.3+8.33 BW (P=0.0001; r=0.998), a clear relationship that was not observed for other commercial foods. The non-commercial part of the diet had higher fat (13 and 8 g/megajoule, MJ, respectively; P=0.00001) and lower protein (12 and 16 g/MJ, respectively; P=0.00001) compared to the commercial part of the diet. Six out of ten dogs were given treats, and one-fourth was given vitamin/mineral supplements (most commonly daily). Most dogs consumed diets that were nutritionally balanced. No dogs in the study consumed diets that supplied lower amounts of protein than recommended by the NRC (2006). Only two individuals (<1%) were given total diets that were lower than the nutrient profiles in fat. Few dogs consumed total diets that were lower than recommended by the NRC (2006) in calcium, phosphorus, and vitamins A, D and E (2, 1, 3, 5, and 3% of the individuals, respectively). A few individuals consumed higher levels of vitamins A and D (<1 and 4%, respectively) than recommended. Diets that deviated from recommended levels were those consisting of only table foods with no supplements (too-low in vitamins and minerals) or commercial foods+no table foods supplied with extra vitamin and mineral supplements (too-high in vitamins and minerals).

Reproductive endocrinology and postweaning performance in the multiparous sow. Part 1. Influence of metabolic status during lactation.

The metabolic status of the sow during lactation might influence reproductive endocrinology and the postweaning reproductive performance. With regard to the multiparous sow, previous studies addressing this topic are scarce and the results inconsistent. Blood samples were collected from 18 multiparous sows during lactation and after weaning for analysis of nonesterified fatty acids (NEFA), triglycerides, creatinine, urea progesterone, LH, and estradiol-17beta. Based on the average preweaning NEFA levels the sows were divided into a "high" and a "low" catabolism group. The NEFA values were higher in the "high" group during each of the last 3 weeks of lactation. The levels of urea, creatinine and progesterone were similar (P > 0.05) in the two groups throughout the study. Reproductive functions seemed equally inhibited during lactation in the two groups and there were no differences in postweaning reproductive performance. The results suggest that metabolic rate during lactation varies considerably between equally nourished multiparous sows but this has no influence on postweaning reproductive performance.

Reproductive endocrinology and postweaning performance in the multiparous sow. Part 2. Influence of nursing behavior.

The reason for variation in postweaning reproductive performance among multiparous sows is to a large extent unknown. In the present study, the influence of nursing behavior was explored. Blood samples were collected during lactation and after weaning from 18 multiparous sows for cortisol, LH, estradiol-17beta (E2), and progesterone analysis. Sow and piglet behavior was videotaped. The sows were fed according to litter size and slaughtered after the second postweaning estrus. The sows were divided into two groups based on average values for the different behavioral parameters. Sows with a long average nursing duration (long group) had lower average and basal LH levels on Day 14 and 21 of lactation as compared to the sows having a short average nursing duration (short group). In the long group, concentrations of E2 were lower the day after weaning, but on Day 15 and 21 of lactation no differences were noted between the two groups. Postweaning performance seemed impaired in the long group, though, differences were not significant. The sows in the long group were heavier and tended to lose less weight during lactation. To conclude, nursing duration seems to influence the extent to which reproductive functions are inhibited during lactation.