The role of phytogenic feed additives in stress mitigation in broiler chickens.

The increase in global temperature and consumers' welfare has increased the use of phytogenic feed additives (PFA) to mitigate the negative effects of heat stress on chickens in recent years. Various bioactive compounds capable of improving the thermotolerance of broiler chickens during exposure to thermal challenges have been identified in different plant species and parts. This review is an overview of the roles of bioactive compounds of different PFA, such as polyphenols and flavonoids, antioxidants, growth-promoting and immune-modulating agents, in heat stress management in broiler chickens. Common PFA in use, particularly in tropical environments, are also discussed. An understanding of the roles of the PFA in chickens' thermotolerance could further stimulate interest in their use, thereby improving the birds' productivity and addressing consumers' concerns. This review collates the existing data on the roles of herbs in mitigating heat stress on chickens and highlights future research perspectives.

Naringin prevents cyclophosphamide-induced erythrocytotoxicity in rats by abrogating oxidative stress.

Earlier reports have shown that Cyclophosphamide (CYCP), an anti-malignant drug, elicited cytotoxicity; and that naringin has several beneficial potentials against oxidative stress and dyslipidaemias. We investigated the influence of naringin on free radical scavenging, cellular integrity, cellular ATP, antioxidants, oxidative stress, and lipid profiles in the CYCP-induced erythrocytotoxicity rat model. Rats were pretreated orally by gavage for fourteen consecutive days with three doses (50, 100, and 200 mg/kg) naringin before single CYCP (200 mg/kg, i.p.) administration. Afterwards, the rats were sacrificed. Naringin concentrations required for 50 % scavenging hydrogen peroxide and nitric oxide radical were 0.27 mg/mL and 0.28 mg/mL, respectively. Naringin pretreatment significantly (p < 0.05) protected erythrocytes plasma membrane architecture and integrity by abolishing CYCP-induced decrease in the activity of erythrocyte LDH (a marker of ATP). Pretreatment with naringin remarkably (p < 0.05) reversed CYCP-induced decreases in the erythrocytes glutathione levels, activities of glutathione-S-transferase, catalase, glutathione peroxidase, and glutathione reductase; attenuated CYCP-mediated increases in erythrocytes levels of malondialdehyde, nitric oxide, and major lipids (cholesterol, triacylglycerol, phospholipids, and non-esterified fatty acids). Taken together, different acute pretreatment doses of naringin might avert CYCP-mediated erythrocytes dysfunctions via its antioxidant, free-radical scavenging, and anti-dyslipidaemia properties.

Naringin prevents cyclophosphamide-induced hepatotoxicity in rats by attenuating oxidative stress, fibrosis, and inflammation.

Cyclophosphamide (CYCP), a synthetic alkylating antineoplastic, disrupts both cancerous and non-cancerous cells to cause cancer regression and multi organotoxicity respectively. CYCP-induced hepatotoxicity is rare but possible. Evidence has shown that naringin has several beneficial potentials against oxidative stress, inflammation, and fibrosis. This study examined the chemoprotective potentials of naringin on exited radical scavenging, hepatic integrity, oxidative stress, fibrosis, and inflammation in CYCP-mediated hepatotoxicity. Rats were pre-treated orally by gavage for fourteen consecutive days with three doses (50, 100, and 200 mg/kg) of naringin before single CYCP (200 mg/kg, i.p.) administration. Subsequently, the rats were euthanized; blood and liver were removed, and assessed for serum and hepatic enzymes, oxidative stress, inflammation, and gene expression dynamics. Naringin concentrations required for 50% scavenging hydroxyl radical and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulphonic acid) radical cation were 0.32 mg/mL and 0.39 mg/mL, respectively. Pretreatment with naringin significantly (p < 0.05) abolish CYCP-induced changes in the activities of serum and hepatic ALT, AST, GGT, ALP, and LDH. Pretreatment with naringin remarkably (p < 0.05) reversed CYCP-mediated increases in hepatic levels of malondialdehyde, hydroperoxide, and nitric oxide; reverse CYCP-induced decreases in the hepatic glutathione levels, activities of catalase, glutathione peroxidase, and glutathione reductase; and also attenuated CYCP-induced upregulation of expression of hepatic chemokine (C-C motif) ligand 2 (CCL2), interferon alpha1 (IFN-α1), interleukine-1ß, interleukine-1 receptor, and transforming growth factor beta 1 (TGF-ß1). Taken together, different doses of naringin can prevent CYCP-induced oxidants generation, hepatocytes dysfunctions, oxidative stress as well as inflammatory perturbations in rats when pre-administered for as few as 14 days.

Effects of vitamin K dietary supplementation in pulmonary dysfunction induced by 7,12-dimethylbenz[a]anthracene in rat.

One of the well-known toxicants of the mammary tissue is 7,12-dimethylbenz[a]anthracene (DMBA). This study was carried out to investigate the possible prophylactic's role of increased dietary intake of vitamin K on the induction of toxicity in the lung tissue. Twenty-eight Wistar albino rats (120-150 g) were randomly divided into different groups. Group 1 served as the control and were fed with a normal diet (containing the recommended daily allowance of vitamin K (0.0075%)). Groups 2 and 3 received a single dose of DMBA (80 mg/kg body weight) intragastically. In addition, group 3 rats were maintained on surplus vitamin K diet (0.075% diet) as against the group 2 animals that were on a normal diet. Group 4 rats were on surplus vitamin K diet (0.075% diet) throughout the experimental period of 16 weeks. Our results revealed that supplementation of diet with surplus vitamin K significantly increased the activities of catalase. Superoxide dismutase, glutathione-S-transferase, and glutathione peroxidase were significantly increased in the serum and lungs when compared with the DMBA-treated group, which was maintained on a normal diet. Significant alterations in malondialdehyde, nitric oxide, granulocyte-macrophage colony-stimulating factor, and interleukin 17F were observed in rats challenged with DMBA-fed normal diets but were normalized in rats with surplus vitamin K. These alterations and reversal were confirmed by histopathology studies. This suggests the prophylactic benefit of increased dietary intake of vitamin K without any observed deleterious effect on DMBA-induced pulmonary toxicity.

Genetic diversity, phylogeographic structure and effect of selection at the mitochondrial hypervariable region of Nigerian chicken populations.

In this study, the maternal genetic diversity, phylogenetic relationship and effect of natural selection on indigenous chickens from Nigeria were assessed. A total of 397-bp fragment of the mitochondrial DNA (mtDNA) D-loop region of 171 indigenous chickens from four populations of Nigeria and four commercial egg line strains (two Anak titan, one Giriraja and one Yaffa) as out-groups were analysed. Thirty-one haplotypes (28 from Nigerian chickens and three from commercial strains) and 34 polymorphic sites were identified. The mean haplotypic and nucleotide diversity were found to be 0.39 ± 0.05 and 0.02 ± 0.02, respectively. Majority of Nigerian chicken haplotypes observed were grouped into haplogroup D which originated from Indian subcontinent, suggesting a single maternal lineage. Genetic variation within and between populations accounted for 97.30 and 2.70% of the total genetic variation, respectively, which is in agreement with a recent and maternal founding effect. High number (4) of negatively selected sites observed based on single likelihood ancestral counting (SLAC) model indicated that the sampled Nigerian chicken populations were undergoing purifying selection. This study concluded that there was relatively high genetic diversity and differentiation, thus, this information will probably paveway for further evaluation studies, preservation and improvement of Nigerian chickens as genetic resources towards ensuring food security.