Understanding the genetic structure of economically important traits in dairy cattle is a fundamen-tal requirement before designing any effective breeding program. This study was conducted to estimate genetic parameters, including heritability and genetic and phenotypic correlations, for 305-day Milk Production (P305), Calving Interval (CI), Dry Period (DP), Peak Yield (PY), and Days to Peak Yield (DPY) in Holstein-Friesian dairy cattle in Indonesia. The data were collected from 2017 to 2024 and analyzed using the restricted maximum likelihood (REML) procedure. The overall least-squares means were 8,178.04 ± 23.08 kg for P305, 395.37 ± 1.21 days for CI, 66.60 ± 0.53 days for DP, 40.60 ± 0.12 kg for PY, and 78.00 ± 0.58 days for DPY. Heritability estimates were moderate to high for P305 (0.40 ± 0.02) and PY (0.48 ± 0.02), low for CI (0.18 ± 0.02) and DP (0.10 ± 0.02), and very low for DPY (0.03 ± 0.01). A strong positive genetic correlation was found between P305 and PY (0.99). These re-sults provide useful baseline information for developing a National Dairy Cattle Improvement Program in Indonesia's tropical management conditions.
In this study, the effects of dietary supplementation with Lactococcus lactis and Bacillus licheni-formis on broiler performance, metabolizable energy, intestinal morphology, and ileal microflora were evaluated. A total of 300 unsexed Cobb strain broiler chickens were divided into three treatments. Treatment T1 served as the control with a basal diet plus 0.1% CaCO₃ placebo, T2 received a basal diet supplemented with 0.1% Lactococcus lactis and Bacillus licheniformis at 10⁵ CFU g⁻¹, and T3 received the same probiotic combination at 10⁶ CFU g⁻¹. Probiotic supplementation improved growth performance, as indicated by increased body weight gain, improved feed efficiency (FCR), and higher metabolizable energy. Regarding intestinal microflo-ra, T2 reduced Escherichia coli populations, whereas T3 increased lactic acid bacteria; however, the increase in lactic acid bacteria in T3 was not accompanied by a reduction in Escherichia coli (P<0.05). Treatment T3 produced the lowest FCR value of 1.49 compared to the control (1.60) and the highest metabolizable energy of 3372 kcal kg⁻¹, indicating improved nutrient utilization efficiency. Histological evaluation showed a tendency to increase intestinal villus height, with the highest value observed in treatment T2 (1175.39 μm), suggesting improved intestinal absorptive capacity. It was concluded that Lactococcus lactis and Bacillus licheniformis supplementation has the potential to improve performance, intestinal health, and metabolizable energy in broiler chickens, although the ef-fects on microbial populations depend on the dosage.
Proteases are valuable industrial enzymes, yet most commercial preparations in Indonesia remain imported, underscoring the need to identify local, efficient producers. This study reports, for the first time, the production and characterization of an extracellular protease from Bacillus amyloliquefaciens SLBD, isolated from horse feces. The crude extracellular enzyme was collected at different growth phases and evaluated for proteolytic index, specific activity, and catalytic properties using N-succinyl-Ala-Ala-Pro-Phe-p-nitroanilide as substrate. The crude enzyme exhibited a specific activity of 8.82 U mg-¹, Km of 0.519 mM, Vmax of 192.31 μmol min-¹, and kcat/Km of 1.23×105 M-¹ s-¹. Optimal activity was observed at pH 7–8 and 50 °C, with more than 80% stability retained between pH 6–10 and tem-peratures up to 60 °C. Activity was moderately affected by organic solvents but remained above 70% in methanol and ethanol, and was largely unaffected by nonionic detergents. Metal ions such as Zn²+ slightly enhanced activity, whereas Hg²+ and EDTA caused strong inhibition, implying partial metal dependence. Collectively, the enzyme demonstrates broad operational stability and tolerance to diverse physicochemical conditions. The findings highlight B. amyloliquefaciens SLBD as a promising feces-derived strain producing a robust, solvent- and detergent-tolerant extracellular protease suitable for bio-technological and industrial applications.
Research on sustainable alternative feed ingredients is important to reduce the significant depend-ence on expensive soybean meal. In this study, the effects of heat-treated hemp seed cake (HSC) and phytase supplementation on the nutritional composition, fatty acid profile, physicochemical properties, and sensory traits of broiler chicken meat were evaluated. A total of 210 unsexed Ross day-old chicks were randomly allocated to seven dietary treatments with six replicates each: soybean meal-based diet (control), 15% HSC with or without phytase (1000 FTU/kg), autoclaved HSC (120°C, 10 min) with or without phytase and oven-heated HSC (120°C, 20 min) with or without phytase. Meat dry matter, crude protein, crude fat and ash contents were not affected by dietary treatments. Thigh meat pH was lower (P<0.05) for autoclaved HSC, and lower (P<0.05) for phytase-supplemented unheated HSC diet compared to the control. HSC supplementation enhanced breast meat redness and yellowness and in-creased thigh meat lightness and yellowness (P<0.05) without affecting breast meat lightness. The in-clusion of HSC decreased total saturated fatty acids, increased polyunsaturated fatty acids, omega-3 and omega-6 contents and resulted in a lower omega-6/omega-3 ratio (P<0.05). Unheated HSC nega-tively impacted breast meat appearance, odor and chewiness (P<0.05) while heat-treated HSC did not impair meat sensory quality compared to control diet. In conclusion, feeding 15% of HSC with or with-out phytase could partially replace soybean meal without negative impacts on meat quality and im-prove the fatty acid profile of broiler meat.
A feeding trial investigated the effects of C. erectus leaf extract supplementation on growth per-formance, nutrient digestibility, microbial population, and intestinal histomorphology of broiler chick-ens. A total of three hundred one-day-old broilers were allocated in a completely randomised design to evaluate five dietary treatments with five replicates of twelve broilers each. The experimental diets were formulated by supplementing the basal diet with C. erectus leaf extract at 0%, 0.25%, 0.50%, 0.75%, and 1.0%. Feed and body weight were recorded weekly; digesta samples were collected on the slaughter day. Results showed that dietary supplementation with C. erectus leaf extract did not affect (P > 0.05) growth performance and nutrient digestibility. The 0.75% and 1% C. erectus leaf extract enhanced (P<0.05) relative ileum length, whereas 0.5% increased (P<0.01) relative ileum weight. The relative gizzard weight was higher (P<0.05) in birds fed 1%, whereas the lowest in birds given 0.25%. Birds receiving 0.25% and 0.5% C. erectus leaf extract showed a significant reduction (P<0.01) in Escherichia coli numbers, whereas dietary inclusion of 0.75% resulted in an increase (P<0.01) in Sal-monella numbers and improved (P<0.05) the gut morphology. In conclusion, C. erectus leaf extract at 0.25 %could be supplemented to the broiler diet, resulting in improved intestinal morphology, reduced Escherichia coli numbers without any detrimental impacts on the growth performance and nutrient digestibility.
