Annual Research & Review in Biology

The enzyme DGAT1 is involved in the synthesis of triglycerides. The most well-known polymorphic variant of the DGAT1 gene is substitution of lysine with alanine at position 232 of the protein (K232A). The 232K allele is associated with increased enzyme activity and a higher content and yield of fat in milk. There is less data on the frequencies of alleles of this replacement in different breeds in literature. In our research work, we analyzed the frequencies of genotypes and alleles of the K232A substitution in the DGAT1 gene in 4 breeds of Russian selection: Black-and-white Holsteinized, Kalmyk, Ayshire and Angus. We demonstrated that the K allele is minor in the populations of the analyzed cattle breeds.

Bioethanol, produced by anaerobic fermentation of carbohydrates with microorganism is a liquid fuel used either as energy source or as an additive/enhancer for fossil petrol. This research was carried out to explore the potential of cocoyam starch as an alternative feedstock for bioethanol production. Cocoyam corms and cormels were peeled, dried and milled to flour, the slurries were then mashed with different enzyme cocktails comprising of amylase, glucoamylase and protease enzymes. The saccharified wort obtained was fermented with yeast; Saccharomyces cerevisiae without exogenous nutrient supplementation. Two fermentation processes were employed. Simultaneous Saccharification and Fermentation (SSF) and Separate Hydrolysis and Fermentation (SHF). Glucose liberated during mashing was determined by glucose oxidase method and it was found that enzymatic hydrolysis of cocoyam flour was effective in yielding favourable levels of fermentable glucose up to 86g glucose/100g substrate with batch 1 of enzymes. Ethanol production was measured from the cocoyam mash and it was found that S. cerevisiae produced ethanol levels equating to 398 L/ton which compares favourably with yields from cassava 280 L/ton and corn 420 L/ton. These observations indicated that cocoyam can serve as a very cheap alternative biomass for bioconversion to bioethanol with minimal inputs.

The study deals with the interaction between some soil physicochemical properties and weather variables on sub-humid tropical rainforest soils of Cross River State, Southeastern Nigeria. The study aims to determine the interactions between soil properties and weather variables of three land uses occurring on the tropical sandy soils. Soil samples were obtained from 10,000 m² of UNICAL Teaching and Research farm (Arable farm), Oil palm plantation and Forestry Teaching and Research farm (Forest and wetland land use) respectively. A total of twenty-seven (27) soil samples were collected with nine (9) samples from each land use at 20 cm depth and at an interval of 50 m with the aid a soil auger and core sampler. The weather variable data from 2012 to 2015 was obtained from NIMET. The result revealed that the sandy soils of Calabar are characterised with coarse, predominantly sandy loam and loamy sand texture with particle size ranging 610-850 g/kg for sand 80 to 240 g/kg for clay and 30-150 g/kg for silt; generally acidic with low to medium organic matter content, low ECEC, low nitrogen, medium available P (15.04 mg/kg, 8.65 mg/kg and 2.78 mg/kg for arable farm, oil palm plantation and forestry land uses respectively). The study showed the correlation coefficient analysis between the high and low impact of weather variables on some soil properties and also recommended a proper management practice such as mulching to avoid direct impact of sunlight on the soil thereby ensuring maximum utilisation of tropical sandy soils of Calabar.

Mesenchymal stem cells (MSCs) are multipotent stem cells that are capable of self-renewal and can be committed into classical mesodermal tri-lineage differentiation (adipocytes, osteocytes and chondrocytes). During chondrogenic differentiation MSCs change their shape due to the reorganization of cytoskeletal components. This has been well documented for human and rodent models. Morphological changes of microtubule network and actin filaments that occur during the chondrogenic differentiation of MSCs from large animal models remain unknown. In this study we described the morphological changes of cell shape, area, actin structures and microtubule array that occur in bovine MSCs during the chondrogenic differentiation of bovine bone-marrow isolated MSCs. Chondrogenic differentiation of bMSCs occur more rapidly on glass substrate compared to the cells plated on vitronectin, and in 7 days after the commitment we observed clusters of small round-shaped cells that expressed glycosaminoglycans. During the differentiation microtubule (MT) array of MSCs became non-radial, and non-centrosomal MTs that grew transversely to the cell radius appeared in the inner cytoplasm and near the cell edges. At the end of differentiation process we observed the thick bundles of MTs that grew in parallel to the cell edge and basket-like structures of curved MTs around the nucleus. The main changes of actin structures in differentiating MSCs included the disappearance of thick transverse stress fibers and actin arches and reorganization of actin into chaotic network of thin cortical fibers. Our results imply the important role of both actin and MT cytoskeletal systems in chondrogenesis and reveals new perspectives for experimental regulation of these process in vitro systems.

Aims: Nonsteroidal anti-inflammatory drugs (NSAIDs) are frequently used to treat both acute and chronic pain in animals, especially when the pain is resulted from inflammatory conditions. NSAIDs work by inhibition of cyclooxygenases (COX) enzymes and reduce the production of key inflammatory mediators prostaglandins and associated chemicals. Prostaglandins have important roles in pain signalling and haemostasis, including platelet aggregation and gastric mucosal protection. There are two known isoforms of cyclooxygenases enzymes, namely COX-1 and COX-2. Notable adverse effects commonly resulted from NSAIDs uses include gastrointestinal ulceration, compromised haemostasis and renal toxicity, which are due to inhibition of COX-1 isoform. Despite the development of COX-2 selective medicines and continuing effort to improve the safety of NSAIDs in routine veterinary practice, adverse effects of NSAIDs still exist and require closed monitoring. This study aims to summarise and evaluate the current literature on reported adverse effects of NSAIDs used in animals and to compare COX-2 selective versus non-selective agents.

Methodology: Literature on reported adverse effects of NSAIDs used in animals over the last decade has been systematically reviewed. Some older sources from the primary literature search have also been included to determine the background information leading to current rationale behind NSAIDs’ therapeutic uses, dosage and route of administration, observed adverse effects and COX-2 selective versus non-selective agents. The primary focus of this study is NSAIDs administered to animals in prospective randomised placebo-controlled blinded trials.

Results: A total of 12 studies that met the inclusion criteria were included in the review, with total 13 NSAIDs being discussed, including meloxicam, phenylbutazone, deracoxib, carprofen, aspirin, firocoxib, vedaprofen, etorolac, ketoprofen, tepoxalin, rofecoxib, licofelone and flunixin. It was found that there were variable findings in comparing the adverse effects associated with COX-2 selective NSAIDs and non-selective NSAIDs. COX-2 selective NSAIDs have been found associated with no adverse effects in some studies and minimal adverse effects in other studies. Severe adverse effects were reported for COX-2 selective NSAID administered at higher than recommended doses or for a long duration and some studies reported reduced adverse effects in COX-2 selective NSAIDs when compared to non-selective NSAIDs. Overall, gastrointestinal adverse effects were predominantly reported, followed by adverse findings relating to haemostasis and renal function. 

Conclusion: Collectively, the findings suggest COX-2 selective NSAIDs provide a clinically useful improvement over non-selective NSAIDs as well as reduce adverse effects when given at recommended dose.