An emerging zoonosis: molecular detection of multidrug-methicillin resistant Staphylococcus aureus from butchers' knives, livestock products and contact surfaces

Methicillin-resistant Staphylococcus aureus (MRSA) transmission in livestock, community, and healthcare settings poses a significant public health concern both locally and globally. This study aimed to investigate the occurrence, molecular detection, and antibiogram of the MRSA strain in fresh beef, contact surfaces, and butchers' knives from the four major abattoirs (Karu, Gwagwalada, Deidei, and Kubwa) located in the Federal Capital Territory, Nigeria. A multi-stage sampling technique was used to collect 400 swab samples from butchers' knives (132), fresh beef (136), and contact surfaces (132). Presumptive colonies on mannitol salt agar were subjected to culture, isolation, and biotyping. The antibiogram was carried out via a Kirby-Bauer disk containing eight antibiotics. MRSA was phenotypically confirmed by oxacillin-resistant screening agar base (ORSAB) and genotypically by PCR to detect the presence of the mecA gene. Out of the 400 samples, 47.24% of fresh beef, 37% of contact surfaces, and 64.33% of butchers' knife swabs were Staphylococcus aureus positive. Thirty-two Staphylococcus aureus-positive isolates were confirmed to be MRSA, 50% fresh beef, 28.12% contact surfaces, and 21.87% butcher's knife swabs. MRSA isolates displayed multidrug-resistant traits, with a high resistance of 90.62% against cloxacillin, and a highest susceptibility of 100% to co-trimaxole. The antibiogram showed MRSA strains to be multidrug resistant. Molecular characterisation of the MRSA detected the presence of the mecA gene at a band size of 163 bp in all isolates. Strict hygiene of butchers, and working equipment in meat processing and marketing should be of top priority.

The Effect of Reduced GnRH Dose on Ovulation and Follicular Dynamics in Ovsynch Programme of Pure and Bunaji-Crossbred Cows

Our objective was to compare the efficacy of reducing GnRH dose from 100 µg to 50 µg on the formation of ovulation and sizes of ovarian structures following Ovsynch in apparently healthy Bunaji and Friesian × Bunaji Cows. Thirty female multiparous-apparently-healthy adult [Bunaji (n = 15) and Friesian × Bunaji (n = 15)] breeds of cattle were used. Five cows each were allocated randomly to three groups [control; full dose (FD), and half dose (HD)]. Cows in the control group were treated with 2 ml normal saline while FD-group received 100 µg lecirelin on day 0, with 500 µg clorprostenol on day 7 and with 100 µg lecirelin two days later. Furthermore, HD-group received the same treatment as FD-cows but the dose of lecirelin was reduced to 50 µg at both times of GnRH administration. Ovarian structures were monitored by ultrasound with a 5-MHZ linear transrectal probe on days - 1 to 12. The ovarian responses of the various groups to first GnRH administration showed (0%, 40% and 60%) ovulation rate for C, HD and FD groups respectively in Bunaji breeds while in Friesian × Bunaji, it was (0%, 60%, 60%). Following second GnRH administration ovulation rate for Bunaji was (20%, 60%, and 60%) for Control, HD and FD-groups, respectively, while for Friesian × Bunaji cows it was (20%, 60%, and 80%). There was no significant difference (p > 0.05) in the days of new follicular wave emergence following the first GnRH administration. It was concluded that 50 µg Lecirelin reduced the cost of drug without affecting the efficiency of Ovsynch protocol.

Effects of crude methanol extract of Adansonia digitata fruit pulp on Naja nigricollis venom-induce toxicity in Wistar rats

OBJECTIVES

This study evaluated the effects of Crude Methanol Extract of Adansonia digitata Fruit Pulp on Naja nigricollis Venom-Induce Toxicity in Wistar rats.

METHODS

A. digitata was extracted using 70% methanol and median lethal dose (LD₅₀) of both the extract and venom were determined using the up-and-down method. Sixty Wistar rats were randomly assigned into 10 groups of 6 rats each and were administered with normal saline, venom only, venom + antivenom, 125 mg/kg, 250 mg/kg and 500 mg/kg crude methanol extract (CME) pre-envenomation, 125 mg/kg, 250 mg/kg and 500 mg/kg CME post-envenomation, and venom + antivenom + 250 mg/kg CME, respectively. Blood samples were collected 8-h post-envenomation in EDTA and plain sample bottles. Erythrocyte osmotic fragility (EOF) test was carried out on the EDTA blood samples while serum was harvested and used for Malondialdehyde (MDA) and Superoxide Dismutase (SOD) assays.

RESULTS

LD₅₀ of the CME and venom was >5,000 mg/kg and 0.889 mg/kg, respectively. N. nigricollis-induced oxidative stress was evident in group B through increased % haemolysis, MDA and lowered SOD activities. The groups treated with antivenom only, 250 mg/kg CME post-envenomation and antivenom +250 mg/kg CME significantly (p<0.05) reduced EOF, MDA values and increased SOD. The CME revealed better ameliorative effect than protective via inhibition of EOF, MDA values and increased SOD activity.

CONCLUSIONS

The CME when administered singly showed more ameliorative properties and the combination of CME with antivenom for protection was not as effective as when compared to single administration.

Evaluation of the toxicity of crude aqueous Pleurotus tuber-regium (Fr.) Singer extract in mice

OBJECTIVES

The study aimed to determine the phytochemical profile and safety of the aqueous extract of Pleurotus tuber regium using laboratory animal model.

METHODS

The pulverized sample was macerated with water and allowed to stand for 24 h, then filtered. Preliminary qualitative phytochemical screening was carried out on the crude extract and LD50 determination was done using standard procedures. Haematological and serum biochemical parameters to assess the kidney and liver functions were carried out using standard methods.

RESULTS

The phytochemical screening revealed the presence of alkaloids, cardiac glycosides, saponins, phenolic compounds, tannins, steroids, carbohydrates, flavonoids and terpenoids. However, anthraquinones were observed to be absent in the extracts. The LD50 of the extract was found to be greater than 5,000 mg/kg when administered orally with no physical signs of toxicity and death over the 14-day period. There was no significant (p>0.05) increase in the level of serum alanine aminotransferase, aspartate transaminase, alkaline phosphatase, blood urea nitrogen and creatinine (p<0.05) when compared to the control group. There was a significant (p<0.05) increase in the total white blood cells of the mice administered with P. tuber-regium.

CONCLUSIONS

This study showed that P. tuber-regium (Fr.) Singer does not possess toxic principles, hence, the wide safety margin observed in the mice.

Comparative effects of artemether and in combination with diminazene aceturate in the treatment of experimental Trypanosoma brucei brucei infection in Wistar rats

This study assessed the effects of artemether and in combination with diminazene aceturate on parasitaemia, weight, haematology and pathology induced by experimentally Trypanosoma brucei brucei infection in Wistar rats. Fifty adult rats comprising 25 each of males and females were assigned into 5 groups of ten rats (five males and five females). Rats in group I was uninfected while groups II-V were infected with T b brucei. Groups II were untreated; III administered diminazene aceturate once; IV and V administered artemether only and in combination with diminazene aceturate respectively for 5 days. Parasitaemia was determined daily, blood was collected for haematology and weight obtained every four days for a period of 32 days. At 24 days post-treatment, rats were humanely euthanized and organs harvested for pathological examination. Results revealed parasitaemia at day 4 post-infection, significant (p < 0.05) decrease in weight, erythrogram and leucogram in all infected rats. Following treatment, there was significant (p < 0.05) decrease in parasitaemia, increased weight gain and improved haematology. Pathological examination revealed significantly (p < 0.05) decreased gross and histopathological lesions in treated groups compared to group II. In conclusion, artemether and in combination with diminazene aceturate produced antitrypanosomal effects against experimental trypanosomosis.