Nutrient evaluation of a pork by-product and its use as environmental enrichment for managed large exotic cats.

North American zoological institutions typically feed ground raw meat diets to large exotic cats. These diets typically are nutritionally complete, but lack physical properties characteristic of whole prey. Lack of mastication and prey manipulation may contribute to behavioral and health challenges. Pork by-products may provide environmental enrichment to mitigate these challenges. The objectives of this study were to evaluate a pig head for nutritional composition and to determine if a pig head was biologically relevant environmental enrichment for managed large exotic cats. Pig heads consisted of: DM: 48.5%; OM: 60.7%; CP: 38.4%; fat: 22.0%; CF: 13.5%; TDF: 3.4%; GE: 4.1 kcal/g DM. Five individually housed exotic cats (Panthera tigris tigris, Panthera tigris altaica (n = 2), Panthera tigris jacksoni, Panthera leo) were observed in 2-h blocks, 24-h before pig head introduction (Baseline), at time of pig head introduction (Enrichment) and immediately after the pig head was removed (Post Enrichment) via instantaneous scan sampling for 4 consecutive weeks. Active behaviors were 55.7% higher on Enrichment compared to Baseline days, and 26.4% higher compared to Post Enrichment days (p<0.0001). Active behaviors were 39.8% higher on Post Enrichment compared to Baseline days (p<0.0001). Total active behaviors were highest (p<0.0001) in week 3 and lowest (p<0.0001) in week 4 with differences as high as 64.5% seen among weeks. In conclusion, pig heads have potential to provide nutrient dense enrichment to large exotic cats, and employing a pig head as environmental enrichment increased active behaviors and did not lose novelty.

Daily feeding regimen impacts pig growth and behavior.

A primary swine production goal is to increase efficiency of lean tissue gains. While many swine production systems currently utilize ad libitum feeding, recent research suggests that altering feeding patterns may impact feed efficiency. Therefore, the objective of this study was to compare two feeding patterns and evaluate their impact on whole body tissue accretion, feeding behavior and activity in growing pigs. Forty eight individually housed gilts (55.9±5.2kg on test BW) were assigned into one of two feeding treatments: 1) Free access to the feeder (Free Access) or 2) twice daily access where gilts were allowed to eat ad libitum between 08:00-09:00h and again from 17:00-18:00h (2×). Pig performance was recorded weekly for 55days and average daily gain (ADG), average daily feed intake (ADFI), and gain:feed (G:F) was calculated. Body composition was assessed in 12 gilts per treatment using dual X-ray absorptiometry (DXA) at day -3 and 55 of treatment, and tissue accretion rates were calculated. Gilt behaviors were assessed via video analysis during week 7 and included time spent eating, feeding rate, enrichment interaction, postural changes, standing, sitting, and lying behaviors. Gilts fed 2× had lower ADG and ADFI compared to Free Access gilts (P≤0.01); however, no treatment difference in G:F was observed (P=0.83). At day 55 gilts fed 2× had a lower fat:protein compared to Free Access gilts (P=0.05). Fat, lean, and protein accretion rates were lower in gilts fed 2× compared to those fed Free Access (P=0.01). Gilts fed 2× ate less frequently and for a shorter duration of time, interacted with enrichment more frequently (P≤0.005), and tended to have less frequent postural changes compared to Free Access gilts (P=0.08). No treatment differences were observed in duration of time spent standing, sitting, or lying (P≥0.39). Although feed regimen did not alter feed efficiency, these data indicate that twice daily feeding reduced gilt adiposity and growth without altering the pig's behavioral expression of hunger. Therefore, twice daily feeding may be a method of increasing percent of lean tissue without negatively impacting gilt welfare.