Animals

Housing systems substantially influence laying hen welfare and product characteristics, yet holistic comparative evaluations across production stages remain limited. This study evaluated the feather condition, plasma corticosterone, egg quality, and yolk fatty acid profiles of Hy-Line Brown laying hens reared in free-range (n = 5340) and indoor floor (n = 5750) systems at 36 and 52 weeks of age. One commercial building represented each housing system, and comparisons were therefore exploratory and specific to the buildings studied. Hens in the free-range building had lower feather damage scores across several anatomical regions than hens in the indoor floor building. Overall plasma corticosterone concentrations were also lower in hens from the free-range building. Free-range eggs exhibited higher Haugh units (82.30 vs. 79.41, p = 0.004) and yolk color scores (12.11 vs. 11.73, p = 0.001), whereas indoor floor housing yielded superior eggshell breaking strength (4.18 vs. 3.87 kg/cm², p = 0.005). Significant housing × age interactions were observed for ALA, EPA, DPA, DHA, and total n-3 PUFA (all p ≤ 0.001); 36-week free-range eggs achieved peak concentrations of α-linolenic acid (0.645%) and total n-3 polyunsaturated fatty acids (1.31%), alongside the most favorable n-6/n-3 ratio (14.71). Conversely, at 52 weeks of age, total n-3 PUFA was lower in free-range eggs than in indoor floor eggs (0.63% vs. 0.90%), resulting in a higher n-6/n-3 ratio (27.63 vs. 21.62). Further, yolk arachidonic acid concentration was higher in 52-week-old indoor floor-housed hens. These findings demonstrate clear trade-offs between physical welfare traits and egg structural durability under commercial conditions, emphasizing that housing evaluations should consider production stage and multi-trait outcomes rather than relying on a single indicator.

Telemetry studies can clarify how reintroduced animals use recipient landscapes after release. We examined post-release movement, space use, site fidelity, and habitat selection in four captive-born Nubian ibex (Capra nubiana) released together with three other ibex in Albaidah National Park, Saudi Arabia. GPS monitoring yielded 24,336 locations over 124.7–365.7 days; two collars malfunctioned prematurely. We estimated tracking-period home ranges using autocorrelated kernel density estimation (AKDE), evaluated temporal variation using generalized additive models (GAMs), compared movements with randomized trajectories, quantified revisitation, and fitted individual-level resource selection functions. Estimated 95% AKDE areas ranged from 54.4 to 175.0 km², and 50% core-use areas from 11.6 to 31.9 km². Home-range areas varied without consistent progressive contraction, three animals shifted their principal areas of use, and some collared individuals moved in close association. All four ibex exhibited lower mean squared displacement than buffered-boundary random-walk simulations (Holm-adjusted p = 0.008–0.015) and repeatedly used previously occupied areas. Terrain ruggedness was positively associated with relative habitat use in all four individuals (odds ratios: 1.24–2.38), whereas associations with NDVI and proximity to recorded water sources varied. These findings provide quantitative baseline information on post-release movement and habitat use, complementing future demographic monitoring to evaluate reintroduction outcomes.

Matrix metalloproteinases (MMPs) are zinc-dependent endopeptidases involved in extracellular matrix (ECM) remodeling. Their activity is regulated by tissue inhibitors of metalloproteinases (TIMPs), maintaining a dynamic balance between matrix degradation and synthesis. Dysregulation of this system can contribute to pathological tissue alterations and various diseases. This review summarizes the current literature on the role of MMPs and TIMPs in diseases affecting various organ systems in veterinary medicine, with a particular focus on the horse and selected conditions in other species. Diseases of the musculoskeletal system, respiratory tract, ocular, gastrointestinal, reproductive, and cardiovascular systems, as well as the central nervous system, neoplastic and infectious diseases are discussed. MMP-2 and MMP-9 in particular are associated with inflammatory and degenerative processes. Increased activity of these gelatinases has been reported in osteoarthritis, laminitis, equine asthma, corneal ulceration, chronic enteropathies, neoplastic diseases and fibrotic disorders. Alterations in the MMP/TIMP balance further indicate pathologic tissue remodeling, angiogenesis, tumor invasion and fibrosis. Individual MMPs may serve as diagnostic and prognostic biomarkers and potential therapeutic targets. However, differences between species, organs and disease stages highlight the need for standardized investigations to clarify their pathophysiological significance and clinical utility in veterinary medicine.