Oxidative Stress of in-Ovo Ochratoxin A Administered during Chick Embryonic Development

Effects of embryo injected with ochratoxin A on growth performance, jejunal morphology and barrier of ducklings

1. This trial investigated the effect on embryo injected with ochratoxin A (OTA) and the growth performance, jejunal morphology and barrier of ducklings to 21 d old.2. Two hundred forty, fertilised eggs were individually weighed and randomly assigned to two groups, a control (CON) and the OTA treatment, according to average egg weight. On d 13 of embryonic development, the treatment group was injected with 8 ng OTA/g egg and the CON group was injected with NaHCO3 solution as a placebo. All newly hatched ducklings were assigned to the CON or OTA group based on the different treatments. Each treatment consisted of six replicates and each included 10 ducklings and the experiment lasted until 21 d of age.3. The results showed that embryos injected with OTA affected the 21 d body weight (BW) and average daily gain (ADG) of ducklings (p < 0.05). OTA exposure increased the relative weights of the liver, pancreas, gizzard, proventriculus and jejunum (p < 0.05); and decreased the relative length of the jejunum of ducklings (p < 0.05). Moreover, jejunal crypt depth increased (p < 0.05) and the villus height-to-crypt depth ratio (Vh/Cd) decreased in the OTA-injected group (p < 0.05). Compared with those in the CON group, the mRNA expression of Zonula Occludens-1; (ZO-1) (p = 0.0582) and Occludin; (p = 0.0687) in the OTA treatment group was downregulated.4. The findings demonstrated that a single low-dose injection of OTA increased body weight and daily gain in ducklings. Moreover, embryo exposure to OTA had negative effects with increased relative weight of organs and the jejunal crypt depth, decreased relative length of the intestine and mRNA expression of tight junctions (ZO-1, Occludin).

Liver and kidney damage in quail embryos hatched from eggs sprayed once with chlorpyrifos during artificial incubation

Birds have enough conditions to be used as bioindicators for the presence of environmental contaminants. Notably, chlorpyrifos (CPF) remains extensively employed in Argentina, particularly in fruit plantations and livestock settings This study aimed to assess the potential impacts of CPF on common quail (Coturnix coturnix) embryos through external eggshell application during key embryonic stages (days 1, 4, and 14). Concentrations equivalent to those used in fruit applications, 5× and 10 × (38.4, 192, and 384 µg/egg), were employed. A 48% commercial formulation of CPF (Pirfos - Icona®) was utilized. An increase in embryonic deaths, as well as a statistical association between the degree of liver or kidney lesions and CPF concentrations was observed. The results suggest that CPF can induce embryotoxic effects with a single exposure to quail embryos and compromise the viability of the organisms. The study suggests a potential exposure risk for embryos through contact with the insecticide on the eggshell's exterior.

A fast and simple protocol to anaesthesia in chicken embryos

Chicken embryos (CE) are an experimental model used as an important life science research tool worldwide, and then, adequate anesthetic protocols must be adopted to avoid the unjustifiable suffering of animals. Thus, our objective was to evaluate different anesthetic protocols in CEs using an easy inoculation route, the shell membrane (SM). We adopted the heart rate by pulse and the CE movements as a parameter of pain by assessing the vase in the chorioallantoic membrane (CAM) through the shell by a sensor of a multiparametric monitor. CEs were distributed into the following groups: (i) association of ketamine (5 mg/CE), midazolam (0.05 mg/CE) and morphine (0.15 mg/CE); (ii) ketamine (5 mg/CE) and xylazine (0.125 mg/CE); (iii) xylazine (0.0125 mg/CE) and morphine (0.15 mg/CE). The stress method used to test the anesthetic potential of the drugs was high temperature stimulation, keeping the CEs 10 cm from the fire of a Bussen nozzle for 30 s. In this experimental model, associations between different drugs decreased the pulse and the movement, indicating possible sedation. After treatment, the CE's submitted to the stress method had the heart rate and movements kept low in the groups ketamine-midazolam-morphine and ketamine-xylazine, while the non-drug-treated group increased heart rate. In a group treated with xylazine-morphine, the heart rate did not decrease, but the movement decreased after the stimulus. As the best results were the combinations of ketamine-midazolam-morphine and ketamine-xylazine, we recommend these associations for use in embryos in the final third of embryonic development in experimental protocols and euthanasia.

Fetotoxicity and Subacute Toxicity of Some Plants Involved in the Treatment of Infectious Diarrhea in Benin

This study aimed to provide data on the subacute toxicity and fetotoxicity of aqueous and hydroethanolic extracts of Daniellia oliveri (Rolfe) Hutch. &amp; Dalziel, Anacardium occidentale L., Diospyros mespiliformis Hochst. ex A. DC., Khaya senegalensis (Desv.) A. Juss., Ocimum gratissimum L., Vernonia amygdalina Delile, Pterocarpus erinaceus Poir., and Manihot esculenta Crantz used in the treatment of diarrheal diseases in Benin. For subacute toxicity, each male and female Wistar rat received by esophageal gavage a maximum of 1000 mg/kg over 28 days following the Organization for Economic Co-operation and Development (OECD) Guideline No. 407. Bodyweight changes, biochemical and hematological parameters were assessed. The fetotoxicity of the extracts was evaluated on Dutch Blue hen eggs at 100 mg/kg and 300 mg/kg. The hatching rate, biochemical and hematological constants were subsequently determined. The subacute toxicity data did not indicate any mortality or signs of toxicity. Also, no significant difference in the bodyweight of the rats and the hematological parameters was noted. Concerning fetotoxicity, a low hatching rate (varying from 20% to 50%) was observed in the batches treated with the extracts at 300mg/kg compared to the rate obtained in the negative control batch (80%). The batches that received the hydroethanolic extracts of Vernonia amygdalina and Manihot esculenta at the tested doses had a hatching rate of 0%. When looking at hematological parameters, no significant difference was noted for all batches. However, an increase in the Aspartate Amino-Transferase (ASAT) values was noted in the batches that received the hydroethanolic extract of Khaya senegalensis and the aqueous extract of Diospyros mespiliformis at 100 and 300 mg/kg. These results explicitly show that the hydroethanolic extracts of Manihot esculenta and Vernonia amygdalina are fetotoxic at the tested doses.

Physiological Changes in Chicken Embryos Inoculated with Drugs and Viruses Highlight the Need for More Standardization of this Animal Model

Several studies have been developed using the Gallus gallus embryo as an experimental model to study the toxicity of drugs and infections. Studies that seek to standardize the evaluated parameters are needed to better understand and identify the viability of CEs as an experimental model. Therefore, we sought to verify whether macroscopic, histopathological, blood count, metabolites and/or enzymes changes and oxidative stress in CE of different ages are specific to the model. To achieve this goal, in ovo assays were performed by injecting a virus (Gammacoronavirus) and two drugs (filgrastim and dexamethasone) that cause known changes in adult animals. Although congestion and inflammatory infiltrate were visible in the case of viral infections, the white blood cell count and inflammation biomarkers did not change. Filgrastim (FG) testing did not increase granulocytes as we expected. On the other hand, CE weight and red blood cell count were lower with dexamethasone (DX), whereas white blood cell count and biomarkers varied depended on the stage of CE development. Our work reinforces the importance of standardization and correct use of the model so that the results of infection, toxicity and pharmacokinetics are reproducible.