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Aflatoxin (AF)-producing fungi such as Aspergillus flavus commonly contaminate animal feeds, causing high economic losses. A. flavus is the most prevalent and produces AFB1, a potent mutagen, and carcinogen threatening human and animal health. Aspergillaceae is a large group of closely related fungi sharing number of morphological and genetic similarities that complicate the diagnosis of highly pathogenic strains. We used here morphological and molecular assays to characterize fungal isolates from animal feeds in Southwestern Algeria. These tools helped to identify 20 out of 30 Aspergillus strains, and 15 of them belonged to the Aspergillus section Flavi. Further analyses detected four out of 15 as belonging to Aspergillus flavus-parasiticus group. PCR targeting the AF genes’ aflR-aflS(J) intergenic region amplified a single 674 bp amplicon in all four isolates. The amplicons were digested with a BglII endonuclease, and three specific fragments were observed for A. flavus but A. parasitucus lacked two typical fragments. Sequencing data of four amplicons confirmed the presence of the two BglII restriction sites yielding the three fragments, confirming that all four strains were A. flavus. In addition, this analysis illustrated the genetic variability within the A. flavus strains.

Introduction: Infection of goats with caprine arthritis encephalitis virus (CAEV) has been detected in variable proportions in many countries all over the world. Here, we investigated the seroprevalence of CAEV in goats raised in Algeria.

ABSTRACT The aim of this study was to determine, using immunofluorescence and in situ hybridization, whether CAEV is capable of infecting goat uterine epithelial cells in vivo. Five CAEV seropositive goats confirmed as infected using double nested polymerase chain reaction (dnPCR) on leucocytes and on vaginal secretions were used as CAEV positive goats. Five CAEV-free goats were used as controls. Samples from the uterine horn were prepared for dnPCR, in situ hybridization, and immunofluorescence. The results from dnPCR confirmed the presence of CAEV proviral DNA in the uterine horn samples of infected goats whereas no CAEV proviral DNA was detected in samples taken from the uninfected control goats. The in situ hybridization probe was complementary to part of the CAEV gag gene and confirmed the presence of CAEV nucleic acids in uterine samples. The positively staining cells were seen concentrated in the mucosa of the lamina propria of uterine sections. Finally, laser confocal analysis of double p28/cytokeratin immunolabelled transverse sections of CAEV infected goat uterus, demonstrated that the virus was localized in glandular and epithelial cells. This study clearly demonstrates that goat uterine epithelial cells are susceptible to CAEV infection in vivo. This finding could help to further our understanding of the epidemiology of CAEV, and in particular the possibility of vertical transmission.

Contamination of livestock feed is a serious problem worldwide during storage. Fungal infection reduces nutritional quality of feed and affects the animal health, thus reducing the livestock profitability. The aim of this study was to investigate the mycoflora of 73 samples representing four raw cereals; (corn, barley, soybean and wheat bran) and three concentrate finished feed of (dairy cow, poultry and pellet). Isolation of internal and external mycoflora was carried out using dilution plate and direct plate methods. The result of the dilution technique revealed that Aspergillus, Penicillium, Fusarium and Alternaria were the most frequently occurring genera. The analyzed samples showed fungal contamination ranging from 18.84 x 10³ CFU/g to 55.23 x 103 CFU/g. Comparing the different feed types, finished concentrates had greater fungal contamination compared to the raw ingredients. The most directed external mycoflora in corn, barley and soybean, using the direct plate technique were Aspergillus (100%, 85.66%, 75%) and Penicillium (83.33%, 50%, 50%) respectively. However, Atlernaria (83.33%, 57% and 75%) and Fusarium (66.33%, 71.33% and 50%) were the most predominant internal mycoflora genera. The overall percentage of fungal infection was higher in non-surface disinfected seeds compared to surface disinfected ones. Fungal infection affected quality of grain through reduction in germination. It seems that livestock feed is highly affected by fungi and special storage and conditioning are required to reduce the fungal infection and protect the animal and human health. [ABSTRACT FROM AUTHOR]

Avian leukosis sarcoma virus-based retroviral vectors containing subgroup A envelope pseudotypes facilitate the effective induction of beta-galactosidase marker gene expression in the cultured primordial germ cells (PGC) of chicken. Analysis of three isolation methods for the PGCs shows that EDTA collection method is the best in isolating a high number of PGCs with high viability after mechanical treatment. Beta-galactosidase expression in PGCs indicates their capacity for in vitro division in 5-day-old chick embryo gonads.

Like antibiotics, extensive uncontrolled use of veterinary vaccines might be a threat to human health in occupational livestock production and subsequently in animal food product consumption. Although veterinary vaccines are necessary to control a large variety of infectious diseases in animals, risk assessment, rules, and regulations are highly justified for the sake of human health and safety. Indeed, during the last century, there have been significant changes in livestock production due to the increasing demand for animal products, and these changes have dramatically augmented the occupational exposure of humans to animals. To prevent risks of cross-reactions of veterinary vaccines in humans, strict guidelines are now followed, in every step of vaccine production and people are aware of the consequences. Besides this, systemic biology approaches are also being explored to determine host-pathogen relationships. This mini-review examines some of the scientific bases of this type of risk in the era of systemic medicine, as well as the efficacy or inadequacy of preventive regulations. [ABSTRACT FROM AUTHOR]