Senior pets can suffer from a wide range of age-related diseases that can impact the quality of life for the pet and the relationship between a pet and their owner. Dietary fibre plays a key role in shaping the gastrointestinal health in mammalian species. The aim of this study was to investigate the impact of a novel prebiotic fibre blend containing sugar beet pulp, galacto-oligosaccharides, and cellulose on the health of senior dogs when fed on top of a background commercial dry diet. Thirty-two dogs aged >8 years received the prebiotic fibre blend as a dietary topper for 21 days on top of a nutritionally complete diet using a cross-over study design. The prebiotic fibre blend improved the gastrointestinal health of senior dogs as measured through improved faecal quality scores, a reduction in faecal pH, changes to the taxonomic composition of the gut, and a reduction in faecal branched-chain fatty acids, which are markers for proteolytic degradation. Broader systemic measures, such as changes to serum cytokines, were not impacted by the prebiotic fibre blend. In conclusion, a novel prebiotic fibre blend containing sugar beet pulp, galacto-oligosaccharides, and cellulose improved the gastrointestinal health of senior dogs and could have a range of potential future dietary applications.

Domesticated cats have evolved from the obligate carnivore Felis silvestris. The instinct to eat small frequent meals and a crepuscular feeding rhythm was conserved during domestication. Declining senses, cognitive impairment, and poor oral health decrease food intake in aging cats. Combined with metabolic and physiological changes, they are at risk of sarcopenia and general body condition impairment. Aging cats may, therefore, benefit from modified nutritional strategies to achieve their metabolic energy requirements; however, little is known about feeding patterns in aging cats and influence of food format. This in-home study of 134 aging cats (≥7 years) assessed ad libitum dry, wet, and wet/dry (‘mixed’) feeding regimens to compare 24 h feeding frequency and caloric intakes. Feeding frequency was significantly different between wet and dry (p = 0.02) and mixed and dry diets (p < 0.001), with cats consuming 6.0 (dry), 6.9 (wet), or 7.2 meals (mixed) per day. Mean caloric intakes were significantly higher for dry (262.6 kcal/d) and mixed (222.6 kcal/d) regimens (both p < 0.001) versus wet (138.1 kcal/d). In conclusion, healthy aging cats eat small frequent meals, with feeding frequency and caloric intake influenced by dietary format. These findings support development of evidence-based feeding guidelines for aging cats.

High dietary phosphorus (P), particularly soluble salts, may contribute to chronic kidney disease development in cats. The aim of this study was to assess the safety of P supplied at 1g/1000kcal from a highly soluble P salt in P-rich dry format feline diets. Seventy-five healthy adult cats (n=25/group) were fed either a low P control (1.4g/1000 kcal; calcium:phosphorus ratio, Ca:P 0.97) or one of two test diets with 4g/1000 kcal (4184kJ); Ca:P 1.04 or 5g/1000kcal; Ca:P 1.27, both incorporating 1g/1000kcal (4184kJ) sodium tripolyphosphate (STPP) – for a period of 30 weeks in a randomised parallel-group study. Health markers in blood and urine, glomerular filtration rate, renal ultrasound and bone density were assessed at baseline and at regular time points. At the end of the test period, responses following transition to a commercial diet (total P – 2.34g/1000kcal, Ca:P 1.3) for a 4-week washout period were also assessed. No adverse effects on general, kidney or bone (skeletal) function and health were observed. P and Ca balance, some serum biochemistry parameters and regulatory hormones were increased in cats fed test diets from week 2 onwards (p≤0.05). Data from the washout period suggest that increased serum creatinine and urea values observed in the two test diet groups were influenced by dietary differences during the test period, and not indicative of changes in renal function. The present data suggest NOAELs for feline diets containing 1g P/1000kcal (4184kJ) from STPP and total phosphorus level of up to 5g/1000kcal (4184kJ) when fed for 30 weeks.