http://ir.bdu.edu.et/handle/123456789/17403 2026-10-13T01:48:17Z http://ir.bdu.edu.et/handle/123456789/17423 Availability and Utilization Practices of Organic Acid Feed Additives in Commercial Chicken Production System and Their Effects on Production and Economic Performance of Bovans Brawn Layers and Cobb500 Broilers Birilie, Endalkachew The aim of this dissertation was to assess the availability and utilization of organic acid feed additives in commercial chicken production and their effects on the production and economic performance of Bovans Brown layers and Cobb500 broilers. In the survey study, an assessment was conducted on the availability and utilization of organic acids (OAs) in urban and peri-urban commercial chicken farms of Bahir Dar and Gondar cities in Northwest Ethiopia. A cross-sectional study using a semi-structured questionnaire survey and direct observation on the availability and utilization of OAs as feed additives was employed with a total of 211 commercial chicken farms. Quantitative data were analyzed using descriptive statistics, while qualitative data were analyzed thematically to support quantitative findings. The survey results reveal that OAs are not currently utilized in commercial chicken production within the study areas. All participant (100%) indicated a lack of knowledge about OAs as feed additives, highlighting a complete lack of information among commercial chicken producers. The second study elucidated the potential of dietary citric and malic acid supplementation on growth performance and economic efficiency by replacing conventional antibiotics in Cobb500 broiler chickens. This study used a completely randomized design (CRD) consisting of five treatments with four replicates each. A total of 280 one-day-old chicks were randomly assigned to 5 treatment groups, consisting of 56 chicks per treatment, and further replicated four times with 14 chicks per replicate. The experimental treatments were a basal diet without additives (T1), 60 mg/kg oxytetracycline (T2), 16 g/kg citric acid (T3), 8 g/kg malic acid (T4), and a mixture of 8 g/kg citric acid and 4 g/kg malic acid (T5). Dose-level antibiotics and OAs were determined based on previous studies.The results revealed that the average daily weight gain of chicks was significantly (P<0.05) different among the treatments during the starter and grower phases. The T3, T4 and T5 groups presented better (62.09, 61.98, and 64.30 g) average weight gain than the T1 group (59.58 g), whereas the mixed OAs mixture showed comparable results to the antibiotic group (64.06 g) in terms of daily weight gain during the overall experimental period. Broilers receiving citric and malic acids showed improved feed conversion ratios. Diets containing a citric and malic acid mixture produced the highest dressed carcass yield (P < 0.05), which was comparable to that of the antibiotic group. Mixed acid group achieved superior relative economic efficiency. The third experiment described the effects of dietary citric and malic acid supplementation on laying performance, egg quality traits, and economic efficiency of commercial Bovans Brown layer hens. This study used a completely randomized design. A total of 260 25-week-old layer hens weighing an average initial body weight of 1609 ± 18.5 g were obtained from the poultry farm of Bahir Dar University and randomly assigned to 5 treatment groups, each with 4 replicates. Experimental layer hens were acclimated to the experimental diets for 7 days and were fed for 120 days. The treatments consisted of basal diets without any additive (T1), with 30 mg of oxytetracycline (T2), 16 g of citric acid (T3), 8 g of malic acid (T4), and a combination of 8 g of citric acid and 4 g of malic acid (T5) per kg of the basal diet. The inclusion levels of additives were selected based on the published literature. The results revealed a significantly higher difference (P<0.001) in hen-day egg production, egg quality traits, and FCR. Layer hens fed OA diets improved the hen-day egg production by 85.51% to 86.54% compared to T1 (77.75%) and T2 (80.07%). Overall, T5 exhibited better performance in terms of FCR, albumin weight, egg mass, total return, and net profit. T5 improved profitability by 13.26% and 11.82% and REE by 16.83% and 17.40% more than T1 and T2, respectively. In conclusion, dietary supplementation with a mixture of 8 g/kg citric acid and 4 g/kg malic acid effective alternative strategy to replace antibiotic feed additives, in broilers, and layer chickens. Therefore, the incorporation of this mixture into broiler and layer production systems is recommended. 2025-12-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/17421 Effects of Soybean Meal and Roasted Full-Fat Soybean Inclusion and Their Partial Replacement on Productive Performance, Egg Quality Characteristics, and Hematological Parameters of Bovans Brown layers Yimer, Yemsrach Ethiopia’s poultry sector, like the other livestock sectors, is transitioning from traditional backyard systems to more intensive commercial production, presenting challenges in feed quality, consistency, and cost. Soybean meal (SBM) is the most preferred protein source in poultry diets when available; however, supply variability, rising costs, and limited data on its nutritional consistency in Ethiopia necessitate evaluation of its quality and the exploration of alternative protein sources. Meanwhile, the recent expansion of soybean production and edible oil processing, particularly in the Amhara Region, which accounts for approximately 39% of national output, has established the region as a major processing hub and an important source of SBM. Despite this potential, the nutrient composition of Ethiopian SBM remains poorly characterized and can vary depending on processing methods, among other factors. Full-fat soybean (FFSB) has emerged as a protein- and energy-rich alternative that can reduce feed costs, but its use is limited by antinutritional factors such as trypsin inhibitors, which require roasting to improve nutrient availability and enhance laying hen performance. The need to develop cost-effective, nutritionally balanced rations using locally available feed resources underscores the importance of this research. This research is aimed to (1) assess the variability in the chemical composition of locally processed SBM, (2) determine the optimal SBM inclusion level in layer diets, (3) evaluate graded inclusion levels of roasted FFSB, and (4) examine the feasibility of partially replacing SBM with roasted FFSB in Bovans Brown laying hens under Ethiopian conditions. The chemical composition of SBM samples from 11 regional processing plants was first analyzed. Subsequently, three separate 12-week feeding trials were conducted using 120 Bovans Brown hens (34 weeks of age) in a completely randomized design, with each treatment replicated three times. The first trial evaluated SBM inclusion levels using five dietary treatments containing 15%, 20%, 25%, and 30% SBM, along with a commercial control diet. The second trial assessed graded inclusion levels of roasted FFSB (0%, 10%, 15%, 20%, and 25%). The third trial examined partial replacement of SBM with roasted FFSB using five dietary treatments: 100% SBM (positive control), 25%, 50%, 75% FFSB replacement, and 100% FFSB (negative control). Laboratory analysis revealed significant (P < 0.05) variation in crude protein (38.42–43.52%), ether extract (1.23–5.27%), crude fiber (5.58– 7.35%), and metabolizable energy (3348.3–3594.8 kcal/kg DM), between SBM samples from different processing plants in Amhara region. A dietary inclusion level of 20% SBM appears to be optimal, resulting the highest numerical hen-day egg production (89.72%) and net return (446.63 ETB), with no adverse effects on egg quality and hematological parameters remaining within normal ranges. Different inclusion levels of FFSB reduced egg production (53.03-63.57%) and feed efficiency (3.07-3.37 FCR) compared to the SBM diet (89.73% HDEP and 2.06 FCR). Although feed costs decreased with increasing FFSB inclusion, lower egg production reduced economic returns, making full substitution of SBM economically unprofitable. Partial replacement of SBM with roasted FFSB (25-75%) maintained hen-day egg production (HDEP), egg mass, and feed conversion ratio (FCR) comparable to the control, with the optimal appears to be in 25% FFSB replacement diet, which achieving the highest HDEP (79.67%) and egg mass (47.44 g/hen/day). However, complete replacement reduced egg production, body weight gain, feed efficiency, and profitability. In conclusion, the observed variability among the sampled Ethiopian SBM sources suggests the need for further multi-location and repeated assessments to better characterize national nutrient variation and to generate the evidence required for future development of country-specific feed composition standards for the Ethiopian feed industry. A 20% SBM inclusion level is suitable for mid-laying hens (34–46 weeks of age), and roasted FFSB can serve as a partial substitute at replacement up to 75%, with optimal results were observed at 25% partial replacement, However, complete replacement of SBM with traditionally roasted FFSB is not recommended until the roasting temperature and heating duration have been optimized and validated to effectively reduce anti-nutritional factors and improve nutrient utilization. 2026-08-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/17420 Farmers’ Perception on Hay-Box Brooder Technology and Evaluation of Least Cost Ration on Sasso and Indigenous Chicken Growth and Carcass Performance in south Gondar Zone Gulilat, Lemma Chicken product is the primary commodity for developing country to increase the Gross Domestic Product (GDP), food security and self-sufficiency. The research was conducted in Farta Woreda, which is located in South Gondar Administrative Zone and 105km and 666km far from Bahir Dar and Addis Ababa, respectively. The objective of the study were to assess farmer’s perception on hay box brooder and to evaluate the least cost ration on Sasso and indigenous breed’s performance under onfarm condition of the South Gondar Zone. The study was consisted survey and experiment to assess the farmers’ perception about the hay box brooder and to evaluate the hay box, least cost ration on growth performance of Sasso and indigenous breeds for eight and twenty four weeks, respectively. A total 450 Sasso and 150 Indigenous day-old chicks were randomly divided into five dietary groups in completely randomized design (CRD) with 3 replications for 60 and 168 days feeding trial for Sasso and indigenous, respectively. A total of 60 Sasso and indigenous matured chicken were randomly selected from each replication for carcass evaluation. The results obtained indicated that, 100% of the households had no awareness of how to use hay box brooders for their chicks growing. After evaluation of the hay box, about 86.7% of the farmers said that the construction of hay box brooder is easy and 53.3, 33.3, and 13.4% of households have grouped the efficiency of hay box as very good, excellent, and good respectively. The majority (80%) of the households who were supposed to use hay box brooder were suitable for exotic breeds rather than indigenous breeds. The increased levels of substitution of a commercial diet with a least cost ration significantly depressed (p<0.001) mean daily feed consumption. Growth rate as measured by mean daily weight gain, mean final body weight, and total feed consumption were significantly lower (p<0.001) in an increased least cost ration. Accordingly, edible carcass components of chicken on 0, 25, 50, and 75% at least cost ration was significantly (P<0.001) higher than 100% least cost ration. The slaughter weight, breast, drumstick, thigh muscle, and dressing percentage of Sasso and the indigenous breed was significantly (P<0.001) lower on the 100% least cost ration as compared to the others. Generally, up to 50% of expensive commercial diets could be economically replaced with the least cost ration without adversely affecting the growth and carcass performance of chicks. 2022-11-01T00:00:00Z http://ir.bdu.edu.et/handle/123456789/17419 Agronomic and Nutritional Value of Napier (Pennisetum Purpureum (L.) Schumach) and Desho Grass (Pennisetum Pedicellatum Trin.) Integrated With Desmodium and Farmyard Manure As Well As Its Effect on Soil Properties of the Land in Upper Blue Nile Basin, Ethiopia Walie, Misganaw Inadequate supply and poor quality of available feed resources is the major challenges affecting livestock productivity in Ethiopian smallholder farmers. To combat this problem, field experiments were carried out in two watersheds of Ethiopia's Upper Blue Nile basin to assess the effects of farmyard manure (FYM) and Desmodium intortum (Green leaf Desmodium) intercropping on agronomic, nutritional value, and soil properties of Napier and desho grass, as well as their effects on natural pasture improvement. In the first experiment Napier (Pennisetum purpureum (L.) Schumach.) and desho (Pennisetum pedicellatum Trin.) grasses were evaluated on cultivated land under FYM and green leaf Desmodium intercropping for the morphological characteristics, dry matter yield (DMY), crude protein yield (CPY), nutritional value, in vitro gas fermentation, as well as their effects on soil physicochemical properties. For this field experiment Napier and desho grasses were planted at the Aba Gerima and Guder watersheds, which represent midland and highland agro-ecologies, respectively using randomized complete block design with factorial arrangements in three replications. The treatments used were Napier or desho grass alone [control], Napier or desho grass with green leaf Desmodium, Napier or desho grass with FYM, and Napier or desho grass combined with green leaf Desmodium and FYM with a total of eight treatment combination. In the second field experiment, effects of FYM and enrichment planting with Napier and desho grass on natural pasture were evaluated at Aba Gerima watershed in terms of species composition, biomass yield, nutritional value, in vitro gas fermentation, and soil properties for two consecutive years. Natural pasture plots were treated with: Napier grass or desho grass, Napier or desho + FYM, Napier or desho + Desmodium uncinatum (Silver leaf Desmodium), and Napier or desho + FYM + Desmodium uncinatum; and untreated plots (natural pasture alone) were used as control with a total of nine treatments. The agronomic characteristics and laboratory data were subjected to two-way analysis of variance using SAS JMP-13. In the first experiment, the DMY and CPY were higher (p< 0.001) with FYM as well as FYM combined with green leaf Desmodium (9.1 to 9.6 t ha⁻¹ and 866.7 to 792.4 kg ha⁻¹) at Aba Gerima and (7.0 to 7.1 t ha⁻¹ and 795.3 to 510.5 kg ha⁻¹) at Guder, respectively. For Napier grass and desho grass there was an improvement in vitro organic matter digestibility (IVOMD) (6.7 vs 4.7%), metabolizable energy (ME) (5.5 vs 4.5%), and volatile fatty acids (VFA) production (23.1 vs 3.0%) in the green leaf Desmodium plus FYM treatments over the control at Aba Gerima. Moreover, the fertilizer treatments at cultivated land, i.e., Desmodium intortum plus FYM groups, showed soil organic carbon (18.4% and 20.5%) and available phosphorous (16.3% and 23.0%) content increments over the control in the same watershed. For the grazing land experiment, biomass yield in the desho + FYM + Silver leaf Desmodium plots (8.4 t ha xix −1 ) was higher (p< 0.001) than natural pasture with Napier grass (5.9 t ha −1 ), desho grass (6.5 t ha −1 ), and control (4.4 t ha ). In addition, grazing land plots treated with Napier + FYM, Napier + Silver leaf Desmodium, and desho + FYM + Desmodium showed soil organic carbon levels that were significantly higher than controls. The findings suggested that green leaf Desmodium plus FYM improves growth, yield, nutritional value, IVOMD, and VFA production by maintaining soil fertility in Ethiopia's Upper Blue Nile basin, facilitating their growth in cultivated land as alternative livestock feed for better production in these areas. Furthermore, desho + FYM + Silver leaf Desmodium produced the greatest improvement in grazing land biomass yield and IVOMD by maintaining soil fertility in the study area. 2023-03-01T00:00:00Z