Emmanuel Oladejo

Dr. Emmanuel Oladejo

orcid

Research Focus & Metrics

Academic Career Length

3Years (2024-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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14 February 2025 in Animals
Verified
Journal Article
Open access
PDF file
EOEmmanuel Oladejo
Emmanuel Oladejo
TGTasha R. Gruhot
Tasha R. Gruhot
SPSeongbin Park
Seongbin Park
GIGhassan M. Ishak
Ghassan M. Ishak
BMBenny Mote
Benny Mote
Jean Magloire FeugangJean Magloire Feugang
Jean Magloire Feugang
This study investigated the impact of an increased arginine (ARG) level in a boar diet on semen production, sperm quality, and seminal plasma proteome. Adult Nebraska Index Line boars were assigned to two groups, one receiving a control diet with 0.77% arginine (n = 4) and the other a high-arginine diet with 1.77% arginine (n = 5). Semen was collected twice a week over the whole experiment, including one week before, six weeks during, and six weeks after the supplementation. Parameters such as semen volume and concentration were assessed immediately after collection, alongside sperm motility and morphology. Centrifugation of raw semen samples yielded seminal plasma for a gel-based proteome analysis. The seminal plasma proteins were extracted, quantified, and separated via 2D gel electrophoresis, allowing protein identification through mass spectrometry. Data analysis involved two-way ANOVA for comparisons (p < 0.05). Results showed that arginine supplementation improved semen volume and total sperm counts, with averages of 21 ± 3 doses in the control group versus 24 ± 2 in the ARG group (p = 0.05). Although sperm motility and morphology remained unaffected (p > 0.05), dietary arginine upregulated ten proteins and downregulated two. In summary, increased dietary arginine did not significantly alter key parameters of semen output or sperm quality but significantly impacted seminal plasma proteome, warranting further research on sperm viability.

25 November 2024 in Animals
Verified
Journal Article
Open access
PDF file
EOEmmanuel Oladejo
Emmanuel Oladejo
SHShamimul Hasan
Shamimul Hasan
SSSusan C. Sotak
Susan C. Sotak
JHJohn K. Htoo
John K. Htoo
JBJames Brett
James Brett
SLShengfa F. Liao
Shengfa F. Liao
Oxidative stress impairs pigs’ health and production performance. This study examined the effects of level and source of methionine (Met) supplementation against the diquat-induced oxidative stress in pigs. Forty growing barrows were randomly assigned to four groups. Groups 1 and 2 received a basal diet that was adequate in energy and nutrients (Diet 1), Group 3 received a DL-Met-supplemented diet, and Group 4 received an MHA-Ca-supplemented diet. After 3 weeks of feeding (Phase 1), pigs were injected with 10 mL saline (Group 1) or 10 mg/kg-BW diquat in 10 mL saline (Groups 2, 3, and 4), and then continually fed for one week (Phase 2). During or at the end of Phase 1, there were no differences in nearly all of the growth performance and redox parameters among the four groups. During or at the end of Phase 2, however, the ADFI and ADG were lower (p < 0.01) in Group 2 than in Group 1 while the serum malondialdehyde content was higher (p < 0.05) in Group 2 than in Group 1. The serum glutathione peroxidase (GPX) activity and liver superoxide dismutase (SOD) activity were lower (p < 0.05) in Group 2 than in Group 1. The serum GPX activity, the serum total antioxidant capacity, and the liver GPX activity were higher (p < 0.05) in Group 3 than in Group 2. There were nearly no differences in these redox parameters between Groups 3 and 4. In conclusion, MHA-Ca and DL-Met, when used at an equivalent bioefficacy level, had similar effects on the pigs’ growth performance and antioxidative status. Therefore, increased Met supplementation can improve pigs’ antioxidative status.

27 April 2026 in Australian Journal of Agricultural, Veterinary and Animal Sciences
Verified
Journal Article
Closed access
NONathaniel F Ogunkunle
Nathaniel F Ogunkunle
EOEmmanuel Oladejo
Emmanuel Oladejo
MOMichael K Olanrewaju
Michael K Olanrewaju
ONOnyekachi O Nwankwo
Onyekachi O Nwankwo
Oxidative stress is closely linked to inflammation and contributes to the onset of different diseases in farm animals, thereby affecting their health, performance, welfare and productivity. Oxidative damage occurs as a result of the accumulation of free radicals and pro-oxidants that overwhelm the animal’s antioxidant defense system. This imbalance impairs growth and reproductive performance, health and welfare, leading to disease susceptibility and reduced productivity. This review highlights the relationship between oxidative stress and inflammation, the production of free radicals, their effect on animal health and welfare, as well as combating oxidative stress with bioactive compounds, minerals and vitamins. Oxidative stress can be prevented through the use of naturally occurring bioactive compounds, vitamins, minerals, appropriate management and production systems. Bioactive compounds and vitamins act by scavenging free radicals through neutralization or by activating the nuclear factor erythroid 2-related factor 2 pathway, which upregulates antioxidant genes and promotes the production of antioxidant enzymes that convert free radicals into less reactive forms. Minerals, on the other hand, serve as co-factors for antioxidant enzymes, thereby enhancing their activity. Additionally, environmental enrichment, animal housing and proper handling can reduce the occurrence of oxidative stress, leading to improved animal health and welfare. In conclusion, oxidative stress can cause significant losses in animal production; however, its prevention through effective management practices and dietary interventions can significantly improve animal health, performance, welfare and productivity. The intestinal microbiota plays a critical role in broiler health, nutrient metabolism, immune function, and overall productivity. Its composition is influenced by multiple factors, with diet being the primary driver alongside genetics, digesta passage rate, and rearing environment. Amid growing restrictions on antimicrobial growth promoters and increasing emphasis on sustainable production, fermented diets have emerged as a viable nutritional strategy in broiler nutrition. Furthermore, fermentation serves as a valuable tool for valorizing agricultural by-products and developing alternative broiler feed ingredients. Research has shown that fermented feed enhances growth performance, improves gut health, and beneficially modulates the intestinal microbiota, and hence microbiome. This review synthesizes current research on how fermented feeds, including fermented cereals, brans, legumes, pulses, pomaces, and complete rations, influence the composition, diversity, and functional dynamics of the broiler intestinal microbiota. We discuss the chicken gastrointestinal tract, microbiota, fermentation of broiler feed, the mechanisms through which fermented diets interact with the gastrointestinal environment, emphasizing their role in improving gut barrier integrity, immune responses, and nutrient absorption. By integrating recent findings, this paper highlights the potential of fermented feeds as a viable, microbiome-targeted intervention to support sustainable broiler production while addressing contemporary challenges in poultry health and nutrition. Poultry coccidiosis remains a major parasitic disease causing significant economic losses worldwide. Although previous studies have reported its occurrence in Vietnam, there is a lack of region-specific epidemiological and clinicopathological data under distinct agro-ecological and production conditions in Thai Nguyen Province. This study determined the prevalence, associated risk factors, and clinicopathological alterations of coccidiosis in chickens in this region. A cross-sectional survey was conducted from January to December 2024 in six communes of Phu Binh District, with 300 faecal samples examined using the flotation technique for Eimeria oocysts. Infection intensity was semi-quantitatively assessed, while clinical signs, gross lesions (n = 75), and haematological parameters (10 infected vs. 10 healthy chickens) were evaluated. Prevalence differences were analysed using the Chi-square test, and haematological parameters were compared using independent-samples t-tests (P < 0.05). The overall prevalence was 49.00%, with significantly higher rates in chickens aged 1-3 months (67.05%) and in free-range systems (86.90%). Seasonal variation showed higher prevalence in summer (63.04%) and spring (53.57%) compared to winter (33.82%). Infected chickens exhibited diarrhoea, ruffled feathers, lethargy, and anorexia. Haematological analysis revealed reduced red blood cell counts and haemoglobin levels, alongside increased white blood cell counts, heterophils, and eosinophils (P < 0.05). Gross lesions included haemorrhagic enteritis, intestinal ballooning, and mucosal thickening. These findings highlight the high prevalence of coccidiosis in Thai Nguyen Province and provide region-specific evidence to support targeted control strategies and improved biosecurity measures.

21 February 2026 in Animals
Verified
Journal Article
Open access
PDF file
EOEmmanuel Oladejo
Emmanuel Oladejo
Olivier MunezeroOlivier Munezero
Olivier Munezero
NONathaniel F. Ogunkunle
Nathaniel F. Ogunkunle
BSBarbara Still
Barbara Still
AHAdam Handy
Adam Handy
MMMark W. Murphey
Mark W. Murphey
The increasing global demand for animal-source protein underscores the importance of sustainable livestock systems, including commercial rabbit production. Rabbits are valued for their short production cycle, high prolificacy, efficient feed utilization, and favorable meat quality. In parallel, agro-industrial by-products are being explored as functional feed ingredients to improve efficiency and reduce environmental impact. Grape by-products (GBPs), including pomace, seeds, stalks, and derived extracts, are rich in polyphenols, dietary fiber, and lipid bioactives with potential physiological benefits. This scoping review synthesizes current evidence regarding the effects of GBPs on rabbit health, growth performance, nutrient digestibility, reproductive function, and meat quality. Available studies indicate that moderate dietary inclusion can enhance antioxidant status, support immune function, modulate gut fermentation, and improve meat oxidative stability without consistently compromising growth performance when appropriately formulated. Benefits appear particularly evident under environmental stress conditions. However, outcomes vary according to inclusion level, processing method, and physiological stage, and excessive inclusion may impair nutrient utilization due to fiber and tannin content. Overall, this synthesis identifies functional mechanisms, practical feeding considerations, and key knowledge gaps to inform evidence-based application of GBPs in sustainable rabbit nutrition.