Old beagle dogs have lower faecal concentrations of some fermentation products and lower peripheral lymphocyte counts than young adult beagles

Abstract

The effects of age on microbiota composition, gut fermentation end-product formation and peripheral lymphocyte numbers were compared between old and young adult Beagle dogs fed four kibble diets differing in yeast cell wall contents. The experiment had a double 4 £ 4 Latin square design, one with four mature dogs (4 years old) and the other with four old dogs (10 years old), with four replicates (diets) per dog. In each period a 15 d adaptation period preceded a 5 d total collection of faeces for the digestibility trial. On day 21, fresh faecal samples were collected for the determination of bacterial enumeration, pH, biogenic amine and short-chain fatty acid. Flow cytometry was used for immunophenotypic evaluation. Dogs were fed four kibble diets with similar composition with 0, 0·15, 0·30 and 0·45 % of yeast cell wall (as-fed), respectively. Data were evaluated using general linear models of Statistical Analysis Systems statistical software (P,0·05). No evidence of a difference in faecal bacteria counts between ages was found (total aerobes, total anaerobes, Bifidobacterium, Lactobacillus, Clostridium and Escherichia coli: P.0·15). Faecal concentrations of butyrate, histamine, agmatine and spermine were lower (P#0·05) and faecal pH was higher (P¼0·03) in older dogs than in mature adult dogs, suggesting an alteration in bacterial metabolic activity, or in the rate of intestinal absorption of these compounds. Concentrations of T-lymphocytes, T-cytotoxic lymphocytes and B-lymphocytes were also lower (P#0·01) in older dogs than in mature adult dogs. The study confirmed alterations in peripheral lymphocytes and revealed a reduced concentration of some fermentation end products in the colon of old dogs.

Evidence for greater production of colonic short-chain fatty acids in overweight than lean humans

“…The current results are consistent with this in demonstrating a negative trend between the individual and total SCFAs and age (p<0.05 for propionate and valerate, p<0.09 for total SCFA and butyrate). Moreover, a decrease in faecal SCFA with age was also found in mice, (30) dogs, (31) as well as in human serum. (32) …”

Gut microbiota composition may relate to weight loss rate in obese pet dogs

“…The ANOVA used to compare the faecal SCFA concentrations included age as a factor, as age has previously been found to influence SCFA concentration in dogs (Gomes et al . ).…”

The beneficial role of anti-inflammatory dietary ingredients in attenuating markers of chronic low-grade inflammation in aging

“…While it is possible that, in older canines, an ability to mount a primary humoral response to novel antigens may be retained, the magnitude of the response may be reduced relative to titers achieved in younger animals [25]. In a study in beagles, the concentrations of peripheral T lymphocytes, T cytotoxic lymphocytes, and B lymphocytes were lower in older dogs ( > 10 years) than in mature adult dogs (4 years old) [26]. Aged beagle dogs have decreased neutrophil phagocytosis when compared with young dogs, as assessed by their ability to phagocytize Lactococcus lactis ex vivo [27].…”