Asian Journal of Animal Sciences - Current Issue

Lippia multiflora (Verbenaceae, Mold.) Essential Oil Effect on Broilers’ Growth, Blood Cell Counts and Blood Plasma Lipid Profile

11 June, 2026

Background and Objective: Lippia multiflora (Verbenaceae) is a medicinal plant known for its essential oil, which exhibits antimicrobial, antioxidant and growth-promoting properties. To reduce antibiotics consumption, through animals’ meat, the work aimed to reduce or eliminate synthetic antibiotics use in poultry farming. The experiment examined Lippia multiflora essential oil’s effect on broilers’ growth, their blood cell counts and their blood plasma profile. Materials and Methods: Four diets were composed. The reference diet had no Lippia multiflora (Lm) essential oil (EO). Thereafter, 1, 1.5 and 2 mL of Lm EO were mixed per kilogram of the reference one. Following, 45 chickens divided into 5 groups of 9 birds each were fed on a given diet. The chickens were reared for 8 weeks, separated into 4 weeks for starter and 4 weeks for grower-finisher periods, without any antibiotic treatment. Additionally, chickens were weighed weekly, taking into account the gender. At week 8, 3 chickens of homogeneous weight per gender were slaughtered per diet and their blood was collected into two tubes. One served for blood cell counts and the second served for blood plasma biochemical analysis. An analysis of variance was used to discriminate the least square means, using the Newman-Keuls test at α = 5%. Result: Mixing 1 mL of Lm EO per kg of feed allowed the best outputs. On week 8, 1 mL of Lm EO delivered 2,024.29±57.50 g, the weightiest. Globally, incorporating 1, 1.5 and 2 mL Lm EO induced decreasing live weights for 2,024.29; 1996.19 and 1,965.92 g, respectively (0.861<p<0.927). Also, increasing 1, 1.5 and 2 mL of Lm EO induced an increasing white blood cell count of 48.01, 68.21 and 96.88×10³/μL, respectively (p<0.0001). Finally, 1 mL of Lm EO delivered the highest HDL-cholesterol content for 0.60±0.05 g/L. Conclusion: Lippia multiflora (Lm) essential oil (EO) may have good effects on broilers’ growth and health status. Better, mixing 1 mL of Lm EO per kilogram of feed enhanced broilers’ HDL-cholesterol content.

Effect of Gradually Increasing Levels of Full-Fat Black Soldier Fly (Hermetia illucens) Larvae Meal on Layer Performance

11 June, 2026

Background and Objective: Black Soldier Fly Larvae Meal (BSFLM) has emerged as a promising alternative protein source in poultry nutrition. However, limited research has assessed the impact of gradually increasing full-fat BSFLM on laying hen performance and egg quality. This study aimed to evaluate the effects of graded levels of full-fat BSFLM on the productive performance and egg quality characteristics of ISA brown laying hens. Materials and Methods: A total of 200 ISA brown laying hens were randomly assigned to 25 groups, with 8 hens per group. Five diets were formulated containing 0, 3, 6, 9 and 12% full-fat BSFLM (designated as BSFLM0, BSFLM3, BSFLM6, BSFLM9 and BSFLM12). Each diet was replicated five times. Birds were reared for two months under identical conditions. Parameters measured included feed intake, laying rate, feed conversion ratio, egg weight, albumen height, Haugh unit and egg yolk color. Data were analyzed using R software (v4.3.3) with ANOVA at a 5% significance level. Results: Increasing levels of BSFLM had a significant linear and quadratic effect (p<0.05) on feed intake and feed conversion ratio. Feed intake declined as BSFLM increased, while feed conversion ratio improved. No significant differences (p>0.05) were observed for laying rate, egg weight, albumen height, Haugh unit, or yolk color across treatments. Conclusion: Gradual inclusion of up to 12% full-fat BSFLM in layer diets improved feed efficiency without compromising laying rate or egg quality. However, higher BSFLM levels slightly reduced feed intake. Further research is warranted to evaluate higher inclusion levels and long-term effects on productivity and egg characteristics.

Practical Approach for Estimating Enteric Methane in Smallholder Cattle Systems in Southwestern Vietnam

11 June, 2026

Background and Objective: Accurate estimation of Methane (CH₄) emissions is vital for developing effective mitigation strategies and for national reporting under international climate agreements. The IPCC default emission factors may not account for the characteristics of tropical cattle raised in smallholder systems. This study aimed to evaluate and calibrate empirical models to estimate dry matter intake (DMI) and enteric CH₄ emissions in crossbred Sindhi cattle (Bos indicus) under smallholder conditions in the Mekong Delta, Vietnam. Materials and Methods: Data were collected from 150 smallholder farms between March, 2024 and March, 2025. Morphometric (heart girth, HG; body length, BL) data, live weight (W), weight gain (G), DMI and energy content (GE, DE, ME, NEm) were recorded. Predicted DMI and CH₄ emission models were assessed using the coefficient of determination (R²), residual standard deviation (RSD) and t-tests. Results: The developed model in Brazil demonstrated the best fit with (R² = 0.68, RSD = 0.43, p<0.05) and was insignificantly (p>0.05) different from the actual DMI, followed by a new model (DMI = - 0.297+0.06911×W^0.75+0.867×C, R² = 0.68, RSD = 0.47, p<0.05) developed from local data, in which W = 89.325×HG²×BL (R² = 0.98, RSD = 23.4 and p<0.05). The CH₄ estimation models based on tropical/subtropical cattle (Japan and Kaewpila and Sommart) produced significantly (p<0.05) higher CH₄ conversion factor (Ym, GEI (%)) values (7.33-7.74%) than the IPCC default (6.5%). Under lipid-supplemented diets, the developed model in Japan more accurately tracked emission reductions than the IPCC. Conclusion: The default IPCC parameters tend to underestimate CH₄ emissions in tropical cattle farming systems. The model of the study is suitable for GHG inventories as the IPCC Tier 2 method and, once combined with the developed model in Japan, holds promise for the Tier 3. Further work should incorporate the effects of dietary additives into emission modeling frameworks.