Search Results (2)

This study evaluated the effects of dietary lysine supplementation in low-protein diets on nutrient digestibility, nitrogen metabolism, growth performance, serum biomarkers, and pelt quality in female blue foxes (Alopex lagopus) during the fur-growing period. A total of 105 18-week-old female blue foxes were randomly assigned to seven groups (n = 15 per group). The control group received a standard-protein diet (28% dry matter, DM), while six experimental groups were fed low-protein diets (26% DM) supplemented with 0%, 0.2%, 0.4%, 0.6%, 0.8%, and 1.0% lysine, corresponding to total lysine levels of 0.75%, 0.95%, 1.15%, 1.35%, 1.55%, and 1.75% DM, respectively. Lysine supplementation at 1.35% and 1.55% DM significantly improved the digestibility of ether extract and amino acids, including aspartic acid, glycine, methionine, isoleucine, and tyrosine (p < 0.05). Nitrogen retention increased accordingly, indicating enhanced dietary utilization (p < 0.05). Daily weight gain, particularly from day 15 to day 30, was significantly higher in 1.15–1.55% lysine groups compared to low-lysine groups (p < 0.05), achieving growth performance comparable to the control (p > 0.05). Serum total protein and albumin concentration were significantly improved with increasing lysine levels in low-protein groups (p < 0.01), aligning with those of the control group (p > 0.05). Furthermore, high lysine supplementation significantly improved pelt quality, as evidenced by the increased underfur length and decreased guard hair/underfur in 1.35–1.75% DM (p < 0.05). These findings suggest that lysine supplementation in low-protein diets supports nutrient utilization, growth performance, and metabolic health status while reducing dietary protein content. The optimal dietary lysine range is 1.15% to 1.55% DM (corresponding to 0.4% to 0.8% in air-dry basis), with 1.35% DM (corresponding to 0.6% in air-dry basis) identified as the most suitable level for balancing growth, nitrogen excretion, and pelt quality in fur-growing female blue foxes. Full article

This study investigates Thoroughbred mares exposed or not to supplemental blue light at the end of the gestation. Sixty mares and their 60 foals were selected for the investigation. Guard hair samples were collected from the shoulder just after (within 12 h) the parturition or birth. The foals of the light-treated mares developed significantly (p < 0.05) shorter hair than those of the control mares. A general effect of light treatment on basal hair diameter thinning could be demonstrated (p < 0.005). The maximum force of hair samples of light-treated mares and foals (0.098 and 0.085 N, respectively) was significantly lower than that of the control (0.272 and 0.178 N, respectively). The tensile strength (82.2 N/mm²) of the foal hair samples of the light-treated mares was significantly lower than that of the control foals (121.6 N/mm²). Although no significant difference was found in the elongation (ΔL), the hair of the control animals (mares and foals together) was more elastic than that of the treated animals (335 vs. 262 μm). In conclusion, the supplemental blue light treatment of the pregnant mares has a decreasing effect on both mares and their foals on the mechanical properties of the hair, making it shorter, thinner, and weaker. Full article