Aim:This study was accomplished to test raw milk and certain dairy products sold in local markets of Qena, Egypt, for the presence of Campylobacter coli and Campylobacter jejuni.Materials and Methods:A total of 150 samples of raw milk, kareish cheese, and yoghurt (50 samples each) were subjected first to enrichment in Bolton broth at 42°C for 2 days under a microaerobic condition, subsequently campylobacter blood free selective agar plates were cultured and incubated in the same condition of the broth. Based on the morphological and biochemical themes of the growing colonies, it was further classified into Campylobacter spp. The identified isolates were later affirmed by polymerase chain reaction using primers that were designed to locate hipO genes in C. jejuni and glyA in C. coli.Results:Of the total 150 examined samples of raw milk and soft cheese samples; 37 (24.6%) samples were contaminated with Campylobacter spp. C. jejuni was dominating in this study in 20%, 14%, and 8% of the examined raw milk, kareish cheese, and yoghurt samples, respectively. No sample harbored C. coli.Conclusion:Campylobacter spp. could be detected in 24.6% of the investigated samples. C. jejuni isolated from 14% of the total tested samples, while C. coli could not be detected from the examined samples. Campylobacter spp. is rampant in the areas of poor hygienic conditions making products made from raw milk of public health hazard.

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Mastitis is one of the most important mammary gland diseases impacting lactating animals. Resistance to this disease could be improved by breeding. There are several selection methods for mastitis resistance. To improve the natural genetic resistance of cows in succeeding generations, current breeding programmes use somatic cell count and clinical mastitis cases as resistance traits. However, these methods of selection have met with limited success. This is partly due to the complex nature of the disease. The limited progress in improving udder health by conventional selection procedures requires applying information on molecular markers of mastitis susceptibility in marker-assisted selection schemes. Mastitis is under polygenic control, so there are many genes that control this trait in many loci. This review briefly describes genome-wide association studies which have been carried out to identify quantitative trait loci associated with mastitis resistance in dairy cattle worldwide. It also characterizes the candidate gene approach focus on identifying genes that are strong candidates for the mastitis resistance trait. In the conclusion of the paper we focus our attention on future research which should be conducted in the field of the resistance to mastitis.

Subclinical mastitis (SCM) is an asymptomatic udder infection distributed worldwide that causes significant losses in the dairy industry. The study aims to detect the prevalence of this pathological condition and to identify the most prevalent related pathogens. A total of 440 quarter milk samples from 110 dairy cows were subjected to California mastitis test (CMT) and Modified Whiteside test (MWST) to quantify their efficacy in detecting subclinical mastitis in dairy cows. Quarter-wise prevalence of subclinical mastitis (SCM) was detected in 30.23% and 28.64% samples by CMT and MWST, respectively, while animal-wise prevalence of SCM was recorded in 60% and 55.45% by CMT and MWST, respectively. The left and right forequarter were most susceptible to SCM than other quarters. All positive samples by field tests were subjected to microbiological examinations. Staphylococcus aureus (S. aureus) (48.51%) which considered the primary pathogens among the bacterial isolates followed by Coagulase negative Staphylococci (40.09%), Escherichia coli (E. coli) (38.12%) and Streptococcus agalactiae (S. agalactiae) (13.37%). The sensitivity and specificity of the CMT and MWST were 100%, respectively. The results revealed a strong association between these parameters and the diagnosis of subclinical mastitis in milk samples. In conclusion, the bacteria isolated from SCM play an important role on food poisoning especially S. aureus and E. coli.

Milk and cheese contaminated with Prototheca sp. have zoonotic importance and constitute public health significance to the consumers. In this study, a total of 300 random raw milk and cheese samples were collected from Qena city markets, Egypt, to detect Prototheca sp. Fifty-five of the total 58 isolates of Prototheca were isolated from raw milk and cheese, respectively. The isolates were identified conventionally and microscopically. API system and biochemical tests divided the isolates into four species as follows: P. zopfii, P. blaschkeae, P. stagnora and P. wickerhamii. The most prevalent isolated species was P. zopfii, which was isolated from 12% of buffalo's milk, 16% of cow's milk, 20% of Damietta and 22% of Kareish cheese samples. Polymerase chain reaction assay for P. zopfii confirmation was carried out by amplification of 18S rDNA that classified P. zopfii as genotypes I (28.88%) and II (71.11%). P. zopfii show in vitro resistance to almost all tested types of antimicrobial except for gentamicin and kanamycin. However, nystatin and ketoconazole showed the highest activity among the antifungal. PRACTICAL APPLICATIONSIn this study, high prevalence of Prototheca sp. in the examined raw milk and cheese samples constitutes a public health hazard to consumers. Therefore, sanitary measures during production, storage and processing, as well as sufficient heat treatment, should be recommended. In addition, the present research contributes to increase the knowledge on the diffusion of antibiotic resistance of P. zopfii strains.

A total of 150 random samples of raw cow milk and some locally manufactured dairy products including yoghurt, Kareish cheese and ice cream were collected from various dairy shops, and supermarkets in Qena city, Egypt. Samples were examined for the presence of Enterococcus spp. The investigation revealed that 64, 28, 76, 72 and 16 % of the examined raw milk samples, large and small-scale yoghurt, Kareish cheese and ice cream were contaminated with Enterococcus spp., respectively. Isolates were identified as E. faecalis and E. faecium in percentages of (8 & 32), (16 & 0), (8 & 28), (8 & 36), and (4 & 0) in the examined raw milk samples, large and small-scale yoghurt, Kareish cheese and ice cream, respectively. The obtained isolates were screened for presence of some virulence genes gelE, asa1, esp and cylA using multiplex PCR. The results indicated that gelE, asa1, esp and cylA were located in 53.9, 76.9, 69.2, and 30.8% of the total E. faecalis isolates and in 46.9, 71.9, 53.1, and 34.3 % of the total E. faecium isolates, respectively. The asa1 and esp genes were the predominant virulence traits among all investigated enterococci isolates followed by gelE and cylA genes. Therefore, the results of this study showed that milk and dairy products can play an important role in the spread of Enterococci with virulence potential through the food chain to the human population.

The incidence of Mycoplasma Species in raw milk of different animal species was determined. A total of 240 random raw milk samples were collected from cows, buffaloes, sheep and goats in Assiut and Qena cities, Egypt (30 samples each). Fifteen strains of Mycoplasma were isolated from raw milk. The strains were biochemically characterized followed by PCR assay for confirmation. On the basis of biochemical characterization the strains were divided into 5 species as follow M. arginini, M. bovirhinis, M. bovis, M. species group 7, and M. dispar. M. bovis could not be detected. The most prevalent isolated species was M. bovirhinis which was isolated from 6.67% of cow's milk samples collected from Assiut City. Whereas M. arginini, was the most prevalent species in the examined milk samples collected from Qena City. None of the five M. bovirhinis strains that were identified biochemically were confirmed by PCR assay through amplification of 16S rRNA region of the gene that was amplified at 316 bp. Efforts should be made to protect animals against mycoplasma infection.

In this study the antibacterial activity of lactoferrin against Cronobacter sakasakii (C. sakasakii) as a foodborne pathogen was investigated. The bovine lactoferrin (bLf) was isolated and purified from bovine colostrum by FPLC chromatography and visualized using (SDS-PAGE). Purification efficiency was 90%. C. sakasakii was isolated from a total of 100 samples of infant formula milk powder (IFMP) samples collected randomly from Qena city groceries and supermarkets using HiCrome Enterobacter sakazakiiagar followed by biochemical testing. C. sakasakii was detected in 21% of the total samples examined. The antibacterial effect of bLF on C. sakasakii isolates was tested via performing disk diffusion method using Mueller-Hinton agar. The results revealed that bLF at concentration of 10mg/ml showed the maximum inhibitory effect whereas the least inhibitory effect was recorded at concentration of 1mg/ml. The results indicated that bLF may be useful for inhibition of C. sakasakii in infant formula through supplementation or fortification. More attention should be paid during manufacture and handling of IFMP.