Antimicrobial resistant poultry pathogens are responsible for treatment failure and economic losses, and can also be a source of resistant zoonotic infections representing a risk to human health. In 2006 the European Union banned the use of antibiotics as growth promoters in farm animals and other regions are likely to follow suit. Alternative products and strategies are sought to help maintain animal gut health to reduce the prevalence of pathogens in the food chain. The minimum inhibitory concentration (MIC) of organic and aqueous leaf extracts of Alchornea laxiflora, Ficus exasperata, Morinda lucida, Jatropha gossypiifolia, Ocimum gratissimum, and Acalypha wilkesiana were tested against bacterial poultry pathogens including Staphylococcus aureus, Enterococcus faecalis, Salmonella spp., Escherichia coli, Campylobacter spp., and fungal species (Aspergillus fumigatus, Aspergillus flavus, and Candida albicans) using a 2-fold serial microdilution method. Activity of extracts against biofilms of the pathogens was done using a modified crystal violet staining in vitro assay. The safety of extracts was determined against Vero and Caco-2 cells using a tetrazolium-based in vitro assay. Acetone and cold water extracts of M. lucida had the best activity against three bacteria (MIC = 0.05–0.07 mg/ml) and two fungal (MIC = 0.03–0.15 mg/ml) organisms, respectively. The E. coli isolate and A. flavus were the most susceptible bacteria and fungi, respectively. Caco-2 cells generally displayed higher selectivity index (SI) values compared to Vero cells and average SI values against Vero and Caco-2 cells for both bacteria and fungi ranged from 0.01 to 4.48 and 0.005 to 16.41, respectively. All plant extracts had good anti-biofilm activity (>50%) against at least one organism. The disruption of established biofilm growth by the plant samples proved to be more difficult to achieve than efficacy against planktonic forms of bacteria. This study shows that some of the plant species are potential candidates as alternative feed additives in poultry production. In the future, a poultry feed trial to evaluate their in vivo efficacy as herbal feed additives will be conducted.

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Duck production is a growing poultry enterprise in Nigeria and they are mostly reared in extensive management system. However, the haematological profiles as influenced by the tropical environment have not been well documented. The objective of the present study was to examine the seasonal variation in the haematological parameters of the adult Mallard duck in the tropical environment of Nigeria; as they effects duck production adversely. The Erythrocyte, leucocyte and platelet counts, as well as the erythrocyte osmotic fragility of the domestic duck of the mallard breed during the wet and dry seasons in the hot humid tropical environment of the Experimental Animal Unit of the Department of Veterinary Physiology, Biochemistry and Pharmacology, University of Ibadan, Ibadan, Nigeria was investigated. The study showed that the values of the packed cell volume (PCV), mean corpuscular haemoglobin (MCH) and platelet were significantly higher in the dry season than in the wet season, but the red blood cell (RBC), haemoglobin (Hb), mean corpuscular volume (MCV), mean corpuscular haemoglobin concentration (MCHC), total and differential leucocyte values were similar in the two seasons. The erythrocyte fragility was also higher in the dry season. In conclusion the higher PCV, MCH and platelet values in the dry season might have resulted from haemoconcentration occasioned by higher evaporative heat loss, which is a common occurrence in the dry season. The higher erythrocyte fragility could have been the result of stress induced by the high ambient temperature during the dry season, or higher metabolic rate associated with lactic acid accumulation, which has been shown to increase erythrocyte osmotic fragility.

The most common cause of bacterial diarrhea in humans worldwide is infection with Campylobacter species, particularly Campylobacter jejuni and C. coli. The disease is zoonotic and domestic animals such as poultry, pigs and cattle may act as reservoirs. Colibacillosis is caused by Escherichia coli which is both a food and water borne zoonotic disease from poultry, calves and pigs. The development of resistant strains against the conventional antibiotics has reduced the efficacy of the antibiotics. Therefore, there is urgency to develop drug leads or templates with good activity against these pathogens. The antibacterial activity and safety of acetone, methanol, hot and cold aqueous leaf extracts of Morinda lucida and Acalypha wilkesiana on Campylobacter coli and selected clinical isolates of Escherichia coli was investigated in vitro using serial microdilution and cytotoxicity assays. The MIC values of selected plant extracts against the test organisms generally ranged from 0.03 to 2.50 mg/ml. MIC values of the acetone extracts ranged from 0.03 to 0.46 mg/ml, methanolic extract MICs ranged from 0.15 to 0.78 mg/ml, cold aqueous extract MICs ranged from 0.03 to 2.50 mg/ml while MICs of the hot aqueous extracts ranged from 0.03 to 1.25 mg/ml. The MIC of the positive control, gentamicin, against Campylobacter species ranged from 0.001 to 0.62 mg/ml while those of Escherichia isolates were extremely promising, ranging from 0.0002 to 0.001 mg/ml. The LC50 values of the acetone and cold aqueous extracts of Morinda lucida against the intestinal CaCo‐2 cell line were 0.46 and 0.58 mg/ml respectively while those of acetone, methanolic and hot aqueous extracts of Acalypha wilkesiana were 1.56, 0.11 and 0.19 mg/ml respectively. The selectivity index (SI) values of the acetone extract of Morinda lucida ranged from 2.55 to 9.20 while those of the cold aqueous extracts ranged from 0.23 to 19.33 with the acetone extract having better SI than the cold aqueous extract. The SI values of the acetone extract of Acalypha wilkesiana ranged from 2.22 to 52, methanolic extract ranged from 0.14 to 0.73 and hot aqueous extract ranged from 0.15 to 6.33 with the acetone extract having the best SI relative to cold aqueous, methanolic and hot aqueous extracts of both plant extracts, indicating that the observed antimicrobial activity was not due to toxicity to mammalian cells. These results highlight the potential of Morinda lucida and Acalypha wilkesiana as an alternative for treatment of campylobacteriosis and colibacillosis in poultry. However, in vivo data is necessary to determine the potential usefulness of these plant speciesThis abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.

The domestication of the African giant rat (AGRs) (Cricetomys gambianus) to compliment the inadequate animal protein supplies in Nigeria and its potential to serve as a model for biomedical research is yet to be fully exploited. This study determines the effects of varied crude protein (CP) diet on haematological indices and body weight of AGRs. Blood samples were obtained from the orbital sinus of 30 apparently healthy adult male and female AGRs. The AGR’s were kept in captivity and divided into 6 rats per group (A, B, C, D and E). Group A served as control group. The groups werefed with graded levels of crude protein (CP) of (E) 9.83%, (D) 14.79%, (A) 21.21%, (C) 23.93% and (B) 27.84%. Each chloroform pre-anaesthetized AGRs were weighed at days 0 and 14, 28, 42 and 56, while blood samples were collected at days 28 and 56. The samples were each analyzed for erythrocyte and leucocyte parameters and platelet counts by standard methods. All data collected were subjected to analysis of variance and student t-test. At 28 days post-feeding, AGRs fed with 27.84% CP showed no significant elevations in erythrocyte and leucocyte values compared with control values (21.21% CP). However, at 56 days post-feeding, RBC, Hb, PCV, total WBC, eosinophil, lymphocyte and monocyte counts were significantly lowered in the group fed with 27.84% CP. No significant differences in body weights were observed in rats that were fed 27.84%, 21.21%, 14.8% and 9.8% crude protein diets for 28 and 56 days.This study shows improved body weight with 27.84% CP compared with other crude protein percentage used while 14.79% CP had the best haematological parameters when compared with other crude protein groups.