Evaluation of three popular diets fed to pet sugar gliders (Petaurus breviceps): Intake, digestion and nutrient balance.

Three diets fed to 12 pair-housed sugar gliders, Petaurus breviceps, were evaluated through 5-day intake and digestion trials following 10-day transitions. Diets 1 and 2 comprised liquid formula mixes with added vegetables and fruit, and Diet 3 comprised extruded pellets and a liquid formula. Diets eaten contained 16 -19% crude protein, 3%-15% crude fat, 10%-11% neutral detergent fibre, 4%-20% starch and 8%-49% sugar (dry basis). Calculated individual dry matter intakes (DMI) ranged from 3.9 to 5.1 g/day, representing 58.2-78.4 kJ/day. DMI was greater for Diet 2 (7.2% BW) vs. Diet 1 (5.6; p = .006) and Diet 3 (4.2% BW; p = .003). Although these differences were no longer detectable on a MBW basis, animals were shown to have gained BW (+14.2 g; p = .03) on Diet 2. In addition to nutrient composition differing widely among diets, DM digestibility (DMD) was higher in Diet 1 (91.2%) compared to Diet 2 (87.3%; p = .03), but DMD for Diet 3 (88.9%) did not differ from other diets. Gliders demonstrated ability to digest a variety of energy substrates, including simple sugars (96%-99%), fats (81%-96%) and starches (79%-98%), as well as substantial insoluble dietary fibre (58%-75%), with significant difference among diets demonstrated for some nutrients. Animals displayed selective feeding behaviours, rejecting insoluble fibre in produce and preferring the lipid-coated exterior of pellets. The diets used appeared to be balanced with respect to energy, protein and macromineral content, but may predispose to iron excess, other mineral imbalances (especially Ca deficiency) and obesity-clinical health issues described for pet gliders. Future focus on concentrations, types and utilization of dietary fibre in natural and captive diets, vitamin D metabolism and trace mineral interactions in sugar gliders would assist diet optimization for this highly gummivorous species.

Isoflavone metabolism in domestic cats (Felis catus): comparison of plasma metabolites detected after ingestion of two different dietary forms of genistein and daidzein.

Some felid diets contain isoflavones but the metabolic capacity of cats toward isoflavones is relatively unknown, despite the understanding that isoflavones have divergent biological potential according to their metabolite end products. The objective of this study was to determine the plasma metabolites detectable in domestic cats after exposure to 2 different dietary forms of isoflavones, either as a soy extract tablet (n = 6) or as part of a dietary matrix (n = 4). Serial blood samples were collected after isoflavone exposure to identify the plasma metabolites of each cat. Genistein was detected in its unconjugated form or as a monosulfate. Daidzein was detected as both a mono- and disulfate as well as in its unconjugated form. Other daidzein metabolites detected included equol mono- and disulfate, dihydrodaidzein, and O-desmethylangolensin. No ß-glucuronide metabolites of either isoflavone were detected. Equol was produced in markedly fewer cats after ingestion of a soy extract tablet as a single oral bolus compared with cats consuming an isoflavone-containing diet. The detectable metabolites of the isoflavones, genistein and daidzein, in domestic cat plasma after dietary ingestion has been described in the present study for the first time. The metabolic capacity for isoflavones by domestic cats appears to be efficient, with only minimal proportions of the ingested amount detected in their unconjugated forms. This has implications for the potential of isoflavones to exert physiological activity in the domestic cat when consumed at concentrations representative of typical dietary intake.