Cryopreservation of Piau‐Breed Wild Boar Sperm: Assessment of Cooling Curves and Centrifugation Regimes

This study aimed to assess the effects of different cooling curves and centrifugation regimes used in cryopreservation protocols on the post‐thaw viability of Piau‐breed wild boar (Sus scrofa) sperm using in vitro assessment tests. Two centrifugations (800  g for 10 min and 2400  g for 3 min) and two cooling curves (conventional cooling using nitrogen vapour – freezing 1 and automated cooling using a programmed freezing machine – freezing 2) were tested. Therefore, the treatments were divided into M3 – centrifugation at 2400  g for 3 min and freezing 2; M10 – centrifugation at 800  g for 10 min and freezing 2; R3 – centrifugation at 2400  g for 3 min and freezing 1; and R10 – centrifugation at 800  g for 10 min and freezing 1. No significant differences (p > 0.05) between treatments occurred post‐thawing regarding the total sperm motility means recorded. The mean values of the different treatments were not different from each other regarding the supravital staining (SV), hypo‐osmotic test (HO), sperm–egg binding assay or sperm morphology. This study showed that both the cooling curve and the centrifugation regime affected the quality of post‐thaw sperm, and centrifugation for shorter times and cooling curves using automated cooling are the most suitable for minimizing sperm injury.     

Prevalence of antimicrobial residues in raw table eggs from farms and retail outlets in Enugu State,Nigeria

The use of antimicrobial agents in poultry production results in their accumulation in the body tissues and products such as milk and egg. The subsequent accumulation of these drugs and their metabolites in body cells is known as drug residue. This study was designed to determine the prevalence of antimicrobial residues in eggs from poultry farms and retail outlets in Enugu State, Nigeria. Eggs from 25 selected commercial farms and ten retail outlets were screened for the prevalence of antimicrobial residue. Also, structured questionnaires were administered to 25 commercial farms in the state to determine the management practices and the most widely used antimicrobial drugs in farms and possible association between the management practices and the occurrence of antimicrobial residues in eggs from these farms. All the 25 farms surveyed use oxytetracycline. Eggs from nine of the surveyed farms tested positive for antimicrobial residue and three of the ten surveyed farms also tested positive for antimicrobial residue. No association was observed (p 0.05; Fisher’s exact test) between the occurrence of antibiotic residues in eggs and farm size, feed source and housing systems. This study was able to demonstrate the presence of antimicrobial residues in eggs destined for human consumption. Drugs like nitrofurans which has been banned for use in food animals are still very much in use in Enugu State, Nigeria. Antibiotics given as feed additives may give rise to drug residues in food animals.     

Formation of an Antral Follicle–like Structure of Bovine Cumulus–Oocyte Complexes Embedded Individually or in Groups in Collagen Gels

Culture techniques of antral follicle–like structure (AFLS) derived from cumulus–oocyte complexes (COCs) might provide important insights into follicular development and oocyte maturation. This study was undertaken to investigate the effects of embedding bovine COCs individually (one COC) or in groups (4–5 COCs) in collagen gels on the formation of AFLS and the meiotic status of oocytes. The observations of AFLS formation were performed every second day for 14 days. The AFLS was formed at Day 2 or 4 after the start of culture (Day = 0), irrespective of the culture methods. The mean diameters of AFLS during Days 4–14 using the individual culture method were significantly higher (p < 0.05) than those using the group culture method. However, the AFLS formation rate in the individual culture method was significantly lower compared to that in the group culture method (26.1% vs 62.7%, p < 0.01). Almost all oocytes had undergone the germinal vesicle breakdown stage, irrespective of the culture method or AFLS formation. In conclusion, comparison with the individual culture method revealed that the mean diameters of AFLS in the group culture method were smaller, but more COCs formed AFLS. The group culture method might be useful for evaluating the various hypotheses of follicular formation and interfollicular communication. However, improvement of the group culture system is necessary to prevent the meiotic resumption of oocytes, because the AFLS formation is dependent on the cumulus/granulosa cells surrounding oocytes.     

Methods for Equine Preantral Follicles Isolation: Quantitative Aspects

The aim of this study was to test the use of mechanical and mechanical‐enzymatic methods, saline solution (SS), and PBS solution for the manipulation and isolation of mare ovarian preantral follicles (PAFs). The ovaries were subjected to mechanical isolation (mixer) alone or in association with enzymatic digestion (collagenase). Incubation times of 10 and 20 min were employed. In the first group, 4.1 ± 4.9 PAFs were harvested with the mechanical‐enzymatic method vs 71.1 ± 19.2 with the mechanical procedure, showing a significant difference between methods; using SS and PBS, these numbers were 35.7 ± 34.3 and 39.6 ± 39.6, respectively, with no significant difference between solutions. In the second group, there was significant difference between methods, with 7.1 ± 10.6 follicles harvested with the mechanical‐enzymatic method vs 63.2 ± 22.9 with the mechanical procedure; using SS and PBS, means were 35.5 ± 36.4 and 34.9 ± 31.1, respectively. The mechanical method proved more effective than the mechanical‐enzymatic approach. Both SS and PBS can be used as a media for equine PAFs preparation.     

Magnetic resonance and computed tomography imaging of a carotid body tumor in a dog

A 5-year-old castrated male Labrador Retriever was presented to a referring veterinarian for a swelling in the neck region. Based on the results of histopathology, a carotid body tumor, was diagnosed. The dog was referred to a medical imaging unit for further staging and follow up. This report describes the magnetic resonance (MR) and computed tomographic (CT) appearance of a carotid body tumor.     

Coenzyme Q10 and α‐Tocopherol Prevent the Lipid Peroxidation of Cooled Equine Semen

Biotechnology applied for equine semen increases the levels of reactive oxygen species and reduces the natural antioxidant defence, by both dilution and removal of seminal plasma. Therefore, the aims of this study were to evaluate the effect of adding coenzyme Q10 (CoQ10) and α‐tocopherol (α‐TOH) to the cooling extender, singly or in combination, on sperm parameters, and their effectiveness in preventing lipid peroxidation (LPO) of equine semen during cooling at 5°C for 72 h. Ten adult stallions of proven fertility were used, using two ejaculates each, subjecting them to the treatments with the following concentrations: α‐TOH: 2 mm ; CoQ10: 40 μg/ml; and CoQ10 + α‐TOH: 40 μg/ml + 2 mm for control (C) without the addition of antioxidants and for vehicle control (EtOH) with 100 μl ethanol. The CoQ10 group had a higher percentage of total motility (69.1 ± 16.2%) compared to control (62.1 ± 16.2%) and EtOH (58.1 ± 18.6%). CoQ10 + α‐TOH and α‐TOH groups were most effective in preventing LPO compared to controls (1765.9 ± 695.9, 1890.8 ± 749.5, 2506.2 ± 769.4 ng malondialdehyde/10⁸ sptz, respectively). In conclusion, CoQ10 and α‐TOH were effective during the cooling process of equine semen at 5°C for 72 h, providing increased levels of total motility, as well as lower LPO.     

Comparative assessment of postmortem inspection and immunochromatographic techniques for the detection of bovine tuberculosis in slaughter cattle in Nigeria

Animals with tuberculosis pose some risks to humans, especially in developing countries of the world. In this study, postmortem inspection (PMI) and immunochromatographic assay (ICA) techniques were compared for the detection of bovine tuberculosis (BTB) in slaughter cattle in Enugu State, Nigeria using culture as the gold standard. A cross-sectional study was conducted from January–June, 2011 on animals presented at four purposively selected slaughterhouses in the study area, involving a total of 500 randomly selected animals. Blood samples were collected from the jugular veins of selected animals and serum samples harvested for ICA. Thorough PMI was carried out and tissue samples from the lung, liver, intestine, and lymph nodes were collected, with or without lesions for culture; from the animals examined, culture detected 11 positive cases giving a prevalence rate of 2.2 %, whereas PMI detected 22 positive cases including 7 (out of the 11) positive cases detected by culture, giving a prevalence rate of 4.4 %. Fifteen of the cases detected as positive by PMI were negative by culture. Therefore, the sensitivity and specificity of PMI were 64 and 97 %, respectively. ICA detected 59 positive cases including 10 of the 11 positive cases detected by culture, hence, a prevalence rate of 11.8 %. Forty-nine of the cases detected as positive by ICA were negative by culture. Hence, the sensitivity and specificity of ICA were 91 and 90 %, respectively. In conclusion, the performance of ICA was found sufficiently high to support its use in BTB surveillance and control in cattle in Enugu State, Nigeria.     

Seroprevalence,hematological and biochemical alterations in Brucella-seropositive Muturu cattle in Nigeria

Veterinary Research Communications - This study evaluated the prevalence, hematological and some biochemical alterations in Brucella seropositive Muturu breed of cattle which may change the...     

Bovine ovarian stem cells differentiate into germ cells and oocyte‐like structures after culture in vitro

Stem cells have been isolated from ovaries, and their ability to differentiate into oocytes in vitro has been demonstrated for mice and human, but not for bovine species. The aims of this study were to isolate germline stem cells from bovine ovaries and to evaluate the effects of bone morphogenetic proteins (BMPs) 2 and 4, and follicular fluid on the differentiation of these stem cells into oocyte‐like structures. The ovarian stem cells were isolated and cultured in α‐MEM⁺ supplemented with BMP2, BMP4 or follicular fluid. On days 0 and 14, cells were evaluated for their morphological appearance, viability, expression of alkaline phosphatase and for markers of germ cell formation (VASA and DAZL) and oocyte development (GDF9, ZPA and SCP3) by qPCR. Levels of mRNA were analysed using ANOVA and Bonferroni test (p < .05). The results showed that at day 0, ovarian stem cells expressed specific markers of pluripotency (OCT4, SOX). In addition, these cells were positive for alkaline phosphatase, which is a marker commonly used to identify primordial germ cells (PGCs). After the period of differentiation, cells had morphological features that resemble PGCs and oocyte‐like cells (OLCs). An increase, ranging from five to 14 times, in the expression of VASA was observed in cells cultured in medium supplemented with BMPs and follicular fluid, while the increase in DAZL expression ranged from four to six times. In addition, OLCs had an increase in expression of mRNAs for GDF9, ZPA and SCP3 that ranged from two to eight times. In conclusion, OLCs can be differentiated in vitro from ovarian stem cells and BMPs and follicular fluid are effective in stimulating the expression of mRNAs for germ cell and oocyte markers.