Growth performance, nutrient digestibility and serum biochemical indices of finisher broiler chickens fed varying levels of sorghum in replacement of maize with the supplementation of exogenous enzymes

A 28 days feeding trial was conducted with a total of one hundred and eighty broiler chickens to evaluate the effect of maize-sorghum based diets supplemented with exogenous enzyme on growth performance, nutrient digestibility and serum biochemical indices of finisher broiler chickens. Six experimental diets were formulated in which maize based diet served as Control (T1). Maize in the control diet was replaced by sorghum at the levels of 20% (T2), 40% (T3), 60% (T4), 80% (T5), and 100% (T6), respectively with 50g/100kg enzyme supplementation. The broiler chicks were allotted to six dietary treatments of 30 birds replicated three times with 10 birds per replicate. Dietary Treatments showed significant (P<0.05) effect on final weight and total feed intake. Similar higher statistical values of 1814.67g and 1804.67g were recorded for final weight in birds fed 80% sorghum (T5) and 100% sorghum (T6). Dietary Treatments had significant (p < 0.05) influence on Total protein and cholesterol. Varying levels of sorghum showed (p<0.05) effect on dry matter, crude protein and crude fiber digestibility. In conclusion, feeding finisher broiler chickens up to 100% sorghum replacement level for maize with enzyme supplementation improved growth performance and efficient nutrient digestibility without deleterious effect on the birds. Keywords: Maize-sorghum; Enzyme; Performance; Serum biochemistry; Nutrient digestibility; Broilers

Experimental investigation of R-134a and R-600a refrigerant blend in domestic vapour compression refrigeration system

The refrigeration industry today needs refrigerants with global warming potential (GWP) ≤ 150 according to the European Union protocol, alongside other properties, which no single refrigerant has met as at today. This study focused on blending of existing refrigerants towards obtaining blends with GWP ≤ 150. It investigated the performance of blends of two existing refrigerant, R-134a and R-600a, blended together at ratios of 11%/89%, 7.5%/92.5% and 3.6%/96.4% to form blends K, L and M respectively. The blends were to have, according to the blending ratios, estimated GWPs ≤ 150 using Ali’s model. The blends flammability was tested and the blends were then charged into domestic vapour compression systems, where their operating temperatures and pressures were obtained every 5 minutes during the experimentation. The flammability test shows they are flammable while results obtained at ambient temperatures (37oC, 32oC) under same operating conditions indicated evaporator temperatures (7.7oC, -3.1oC, -3.7oC, -4.7oC, -5.3oC) ; (6.2oC, -3oC, -4oC, -4.8oC, -6.5oC) for R-134a, K, L, M and R-600a respectively. Also the analysis of the results gave corresponding average Coefficient of Performance (COP) of (0.8389, 1.0708, 1.0898, 1.1181, and 1.1373) and (0.8283, 1.0923, 1.1254, 1.1579 and 1.2159) for the aforementioned respective refrigerants at ambient temperatures of 37oC and 32oC, respectively. Thus, the blends can replace R-134a without changing pipe, cooling method and lubricants and still obtain higher COP, though mildly flammable−having slow burning velocity and low heat of combustion. That blend K offers significant improvement in flammability compared to R-600a alongside higher COP to R-134a, makes it the best alternative of the blends.Keywords: Coefficient of Performance (COP), Vapour Compression Refrigeration System, Flammability, Global warming Potential (GWP), Refrigerant, Refrigerant blen

Modelling of clinker cooler and evaluation of its performance in clinker cooling process for cement plants

Cement manufacturing requires cooling down of hot clinker at temperature of about 1350o C to temperature lower than 100 o C in a cooling system known as clinker cooler. Many plants are unable to cool the clinker below 250o C. This challenge led to scaling down of actual clinker cooler to a test rig size in the ratio 25:1 suitable for simulation. Computational Fluid Dynamics (CFD) tools (Solid-Works and ANSYS) were used to achieve the simulation. The clinker outlet temperatures obtained from simulations were validated with theoretical evaluation. Results showed that with clinker and cooling air flow rates of 0.2 kg/s and 0.54 kg/s respectively and with a clinker bed height of 0.6 m. An optimum cooler performance was achieved with clinker outlet temperature of 68 oC. The scaled down cooler was 15% higher than the existing cooler in terms of recoverable energy and 10% high in terms of energy efficiency. Keywords: Clinker Cooler, Computational Fluid Dynamics (CFD), Mass flow rate clinker and Mass flow air and Clinker Furnace

Haematological and biochemical responses of starter broiler chickens fed copper and probiotic supplemented diets

A study was conducted to investigate the haematological and biochemical responses of starter broiler chickens fed copper and probiotics supplemented diets. A total of 180-day old Marshal broiler chicks were randomly allotted to six treatment groups of 30 birds each. The treatments were divided into three replicates of ten birds each; starter diet was formulated and fed for a period of twenty-eight days. The dietary treatments were subjected to complete randomized design arranged in a 2×3 factorial arrangement was made up of probiotics (0 and 500ppm) and copper (0, 125 and 250mg). Data were collected on haematological and serum biochemical indices. Data obtained were analysed using analysis of variance (ANOVA) and, Duncan’s Multiple Range Test was used to separate significant means. Dietary supplementation of copper and probiotics showed significant influence (P < 0.05) on haematological and biochemical indices. Biochemical analyses revealed higher significant (P < 0.05) copper × probiotics interaction values of 42.81 g/l, 19.50 g/l and 23.31 g/l for total protein, albumin and globulin respectively in the birds fed 250 mg/kg copper × 500 ppm probiotics /kg. Birds fed control diet recorded lower significant (P < 0.05) values of 33.85 g/l and 15.40 g/l for total protein and albumin. In contrast, birds fed diet supplemented with 250 mg/kg copper × 500 ppm probiotics /kg recorded least significant (P < 0.05) copper x probiotics interaction values of 149.20 mg/dl, 49.00 mg/dl, 46.48 mg/dl and 81.56 mg/dl for cholesterol, triglyceride, high density lipoprotein and low density lipoprotein respectively. Birds on control diet recorded highest values for cholesterol, triglyceride, high-density lipoprotein and low density lipoprotein (respectively). Dietary copper and probiotics supplementation influenced haematological parameters. Copper x probiotics interaction significantly (P < 0.05) influenced white blood cell, glucose, lymphocyte and eosinophil. Broilers fed diet containing 250 mg/kg copper x 500 ppm probiotics /kg had significantly higher white blood cell (30.65x109/L) than the birds on control diet (26.15 ×109/L). No significant (P > 0.05) copper × probiotic interaction influence on packed cell volume, haemoglobin, red blood cell, neutrophil and monocyte. It can be concluded that dietary copper and probiotics supplementation had significant interaction influence on birds at 250 mg/kg copper × 500 ppm probiotics /kg supplemental level. It could be inferred that the supplementation of both copper and probiotics to starter broiler diet significantly improved the immune-competence of the broiler starters.Key words: haematological; biochemical; copper; probiotics; broiler chicken

Haematology and serum chemistry of finisher broiler chickens fed maize-cassava diet supplemented with methionine and inorganic sulphur

This study was conducted to assess the haematology and serum chemistry of broiler chickens fed maize-cassava diets supplemented with methionine and inorganic sulphur. A total of 270 day-old broiler chicks were randomly assigned to nine treatment groups of 30 birds making 10 birds per replicate group. Starter and finisher diets were formulated and fed for a period of 56 days. Dietary treatments were subjected to Completely Randomized Design in a 3 × 3 factorial experimental layout. Birds were fed diets supplemented with 0, 125, 250 mg/kg DL-methionine and 0, 125, 250 mg/kg inorganic sulphur from CuSO4. Results of haematological parameters showed no significant (p>0.05) difference among the treatment groups except the packed cell volume. The higher value of 31.33% was obtained for PCV in the birds fed diet supplemented with 0mg/kg DL-methionine + 125mg/kg CuSO4. Values recorded for biochemical indices varied significantly (p<0.05) among dietary treatments for total protein, globulin and cholesterol. High significant (p<0.05) values of 50.80 g/l and 29.85 g/l were obtained for total protein and globulin in the birds fed diet supplemented with 125 mg/kg DL-methionine + 250 mg/kg CuSO4. Lower (p<0.05) value of 155.81mg/dl was recorded for cholesterol in birds fed diet supplemented with 250 mg/kg DL-methionine + 250 mg/kg inorganic sulphur. Based on the results obtained for haematological and serum chemistry parameters, it was concluded that supplementation of DL-methionine and inorganic sulphur in broiler diet at 125 mg/kg DL-methionine + 250 mg/kg inorganic sulphur level of supplementation improved dietary protein and had no inimical effect.Key words: Maize-cassava; DL-methionine; inorganic sulphur; haematology; serumchemistry

Seeds and seedlings vigour in tropical maize inbred lines

Seed and seedling vigour is an aspect of seed quality which affects field establishment and performance. Low maize yields have been reported  to be affected by several factors in which poor quality seed with low seed and seedling vigour. Information is scarce on seed and seedling vigour in maize inbred lines developed for tropical environments. Fifteen genotypes of tropical maize (Zea mays L.) inbred lines were evaluated to determine the level of differences in seed and seedling vigour traits, and extent of relationships among traits and their heritability. A substantial amount of genetic variability was found, which suggested that most of the traits under study could be improved through selection and utilized in breeding programs. Positive and signifi- cant interrelationship  among  seed germination  and seedling  traits  and  a positive  correlation  between  seed germination and seed vigour and field emergence showed that these could be given due consideration in crop improvement for seed and seedling vigour. High genotypic coefficient of variation, heritability and genetic advance were obtained for seed germination, seed emergence, shoot length and seedling vigour index I and II, revealing the possibility of improvement in these characters through direct selection. The principal component analysis (PCA) identified seed emergence, shoot length, seedling vigour index I and II and tetrazolium vigour as characters that contributed greatly to variation in seed vigour in the maize inbred lines. Cluster analysis partitioned the genotypes into two groups, with group I consisting of seven genotypes and group II comprised the other eight genotypes, which suggested that hybridization between the two groups could lead to high level of heterosis. Genotype V5  had superior seedling vigour traits compared to other genotypes. Seedling emer- gence, shoot length, seedling vigour index I, seedling vigour index II and tetrazolium vigour are effective characters for good seedling vigour traits in maize inbred lines investigated