Veterinary Sciences

Mannan-oligosaccharides (MOS) may influence microbial and immune-related processes, but evidence concerning palm kernel meal (PKM)-derived MOS-containing products in goats remains limited. The experimental product was a chemically heterogeneous PKM-derived hydrolysate in which M2–M6 oligosaccharides were identified by HPLC–RID; residual sugars and other soluble constituents were also present. Twenty growing male goats received 0, 2.5, 5.0, or 10.0 g hydrolysate/goat/day (n = 5 per treatment) for 90 days. Feed intake, growth, hematological and serum biochemical indices, circulating immune indicators, peripheral blood leukocyte gene expression, and selected ruminal measures were evaluated. Immune and gene-expression outcomes were measured in prefeeding blood collected on Day 90. Ruminal pH and acetate, propionate, and butyrate were measured in a single rumen-fluid sample collected 3 h after feeding on Day 90. Serum IgA showed a positive linear association with supplementation level, whereas IL-1β and IL-6 showed negative associations; these remained significant after false-discovery-rate correction (q = 0.036, 0.012, and 0.012, respectively). Selected immune-related transcripts also differed among treatments, but these endpoint patterns do not establish coordinated immunological regulation or a specific mechanism. Propionate and butyrate showed nominal positive linear associations, whereas the acetate-to-propionate ratio showed a nominal negative association (raw p = 0.028, 0.021, and 0.018, respectively); none remained significant after correction (q = 0.056 for each). Ruminal pH, the sum of the three measured VFA concentrations, feed intake, and growth did not differ detectably. No overt clinical abnormalities requiring veterinary intervention were observed, but the study was not powered to establish safety. These preliminary between-group endpoint associations concern the complete heterogeneous hydrolysate and cannot be attributed specifically to M2–M6 oligosaccharides. Larger, adequately powered studies with pretreatment and repeated measurements are required.

Algal biomass and algal-derived preparations have attracted increasing interest in livestock nutrition because of their potential to modulate the gut microbiota, which plays a crucial role in animal health, immunity, and growth performance. This review focuses primarily on microalgae and cyanobacterial preparations, while also considering selected macroalgae relevant to livestock feeding, without restricting its scope to marine sources. In this narrative review, we summarize recent advances in the physicochemical properties and biological activities of key algal components, such as polysaccharides, polyunsaturated fatty acids, and carotenoids. We assess evidence for changes in potentially beneficial bacteria, including Lactobacillus and Bifidobacterium, and for inhibitory effects against selected pathogenic bacteria, including Salmonella and pathogenic strains of Escherichia coli. We also examine proposed links between these compounds, microbial short-chain fatty acid and bile acid metabolism, and host immune and growth responses. This review discusses practical applications of algal biomass and algal-derived preparations in livestock production, with a focus on inclusion levels and safety assessments. Effects are evaluated in relation to the source organism, preparation, and animal model, rather than assumed to be shared across algal groups. Current challenges and future research directions are also identified to facilitate the efficient utilization of algal resources in sustainable animal husbandry. This review identifies the evidence supporting specific feeding applications and distinguishes observed animal responses from proposed mechanisms.

Non-contact behavioral monitoring is important for low-disturbance husbandry of captive forest musk deer, but variable illumination, shadows, partial occlusion, and low target-background contrast can reduce recognition reliability. This study developed HGS-YOLO26n, a lightweight real-time detector for continuous behavior recording under practical captive breeding conditions. HVIEnhanceStem was used to preserve shallow visual cues under weak illumination and low contrast, AdaGFB adapted feature extraction to posture-related shifts in local discriminative regions, and SDIoU improved bounding-box localization under occlusion and target-scale variation. The model was trained and evaluated using 6760 field images collected from 30 enclosures. HGS-YOLO26n achieved an mAP50–95 of 0.8409, exceeding the YOLO26n baseline by 3.74 percentage points, with 2.84 M parameters and an inference speed of 176.8 frames per second. Validation on continuous videos showed that its behavior-duration and event-count estimates were closer overall to blinded manual observations than those of the comparison models. By converting routine surveillance footage into longitudinal, individual-level records of behavior duration, event frequency, and temporal distribution, the system enables efficient review of behavioral activity across extended monitoring periods. Husbandry and veterinary staff can use these records to compare behavioral patterns across observation periods and return to corresponding video segments when specific changes require verification. This provides a low-disturbance source of quantitative behavioral information for routine husbandry, longitudinal observation, and conservation breeding of captive forest musk deer.