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Open access

Beata Szymczyk, Witold Szczurek, Sylwester Świątkiewicz, Krzysztof Kwiatek, Zbigniew Sieradzki, Małgorzata Mazur, Dariusz Bednarek and Michał Reichert

Abstract

Introduction: The influence of feeding genetically modified MON 810 hybrid maize on the growth and haematological and biochemical indices of rats was tested.

Material and Methods: Two conventional (non-GM) and two test (MON 810) lines of maize were used in semi-purified diets at the level of 40% w/w. The non-GM I, MON 810 I, non-GM II, and MON 810 II maize lines were near-isogenic. A total of 40 male 6-week-old Wistar-derived rats were assigned to four equal feeding groups corresponding to the four maize lines for 16 weeks. Overall, health, body weight gain, clinical pathology parameters, gross changes, and appearance of tissues were compared between groups.

Results: There were no statistically significant differences in the weight gain or relative organ weights of rats, but there were some non diet-related histopathological changes in the liver, kidneys, and spleen. Except for creatinine level, no diet-related effects were observed in haematology or most of the biochemical indices. Transgenic DNA of MON 810 maize was not detected in the tissues or faeces nor in the DNA of E. coli isolated from the rectum digesta of rats given transgenic feeds. In our experiment, various metabolic indices of rats fed non-GM diets or genetically modified (MON 810) maize for 16 weeks were similar. No adverse nutrition-related health effects were detected.

Conclusion: MON 810 maize seems to be as safe as the conventional maize lines.

Open access

Bekir Oguz, Nalan Ozdal, Ozlem Orunc Kilinc and M. Serdar Deger

Abstract

Introduction: Echinococcus granulosus is a zoonotic helminth of the Taeniidae family living in the small intestines of dogs. The hydatid cyst, which is the larval form of this parasite, is observed in sheep, goat, cattle, and many other organisms including humans. It causes a disease called cystic echinococcosis. Identification of strains of E. granulosus in dogs is critical in parasite control and eradication where possible. This study aims to determine the genotype of E. granulosus eggs and prevalence of this parasite in the faeces of dogs in the Van Province using the copro-PCR method.

Material and Methods: This study was conducted between 2015 and 2016 on the faeces obtained from 100 stray dogs from different parts of the Van Province. The coprological examination was conducted using the formalin-ether concentration method.

Results: Taeniidae eggs were found in 10 (10%) out of 100 faecal samples. E. granulosus was detected in 4 out of 10 of these (40%) infected samples. Sequence analysis of positive amplicons obtained from PCR showed that there were sheep strains (G1).

Conclusion: Dogs in Van area are primarily infected with the livestock genotype of E. granulosus, which is thought to be a potential zoonotic threat to humans.

Open access

Mehmet Cemal Adiguzel, Belgi Diren Sigirci, Baran Celik, Beren Basaran Kahraman, Kemal Metiner, Serkan Ikiz, A. Funda Bagcigil, Seyyal Ak and N. Yakut Ozgur

Abstract

Introduction: The study aimed to isolate thermophilic Campylobacter from chickens raised three rearing methods, determine its antimicrobial susceptibilities, and examine resistance-related genes by PCR.

Material and Methods: Cloacal swabs or intestinal contents were taken in Istanbul, Sakarya, and Izmir provinces. Chickens were from small village-based family-run businesses (n = 70), organically raised (n = 71), and conventionally raised broilers (n = 79). The samples were cultured on modified charcoal cefoperazone desoxycholate (mCCD) agar. Suspect isolates were identified with multiplex PCR (mPCR). As per EUCAST standards, MIC values were derived by broth microdilution for tetracycline, ciprofloxacin, nalidixic acid, kanamycin, gentamicin, and erythromycin in isolates of C. jejuni (n = 98) and C. coli (n = 83).

Results: In C. jejuni, 78.6% tetracycline, 87.8% ciprofloxacin, and 81.6% nalidixic acid resistance was detected, but none was to kanamycin, gentamicin, or erythromycin. In C. coli, 98.8% ciprofloxacin and 63.9% nalidixic acid resistance was detected, whereas resistance to nonquinolones was not observed. C257T (Thr-86-Ile) mutation in the gyrA gene of all phenotypically quinolone-resistant isolates was detected through a mismatch amplification mutation assay PCR (MAMA-PCR). It emerged that all isolates bore the tet (O) resistance gene.

Conclusion: Common tetracycline, nalidixic acid, and ciprofloxacin resistance exists in Campylobacter isolated from chickens raised three rearing methods.

Open access

Hanna Czekaj, Wojciech Kozdruń, Natalia Styś-Fijoł, Jowita Samanta Niczyporuk and Karolina Piekarska

Abstract

Introduction: Avian reovirus (ARV) infections in poultry populations are reported worldwide. The reovirus belongs to the genus Orthoreovirus, family Reoviridae. The aim of the study was to evaluate the incidence of ARV infections in the poultry population based on diagnostic tests performed in 2010–2017.

Material and Methods: Samples of the liver and spleen were collected from sick birds suspected of ARV infection and sent for diagnostics. Isolation was performed in 5–7-day-old SPF chicken embryos infected into the yolk sac with homogenates of internal organs of sick birds. Four primer pairs were used to detect the σNS, σC, σA, and µA ARV RNA gene fragments. A nested PCR was used for the detection of the σNS and σC genes.

Results: In 2010–2017, ARV infection was found in birds from 81 flocks of broiler chickens and/or layers, 8 flocks of slaughter turkeys, and in 4 hatchery embryos at 17–20 days of incubation. The primers used in RT-PCR and nested PCR did not allow effective detection of ARV RNA in all virus-positive samples.

Conclusion: The problem of ARV infections in the poultry population in Poland still persist. The primers used for various ARV segments in RT-PCR and nested PCR did not allow effective detection of RNA in the visceral organs of sick birds. The presented results confirm the necessity of using classical diagnostic methods (isolation in chicken embryos, AGID).

Open access

Dalia Hamza, Sohad M. Dorgham, Mahmoud Elhariri, Rehab Elhelw and Elshaimaa Ismael

Abstract

Introduction: Clostridium perfringens is commonly found in the gastrointestinal tract of animals and humans and continues to cause one of the most prevalent foodborne diseases in man.

Material and Methods: A total of 355 samples were examined for the occurrence of C. perfringens: rectal swabs from cattle, sheep, and goats, fresh stool samples from diarrhoea sufferers having been in contact with these animals, irrigation water and soil samples from the husbandry sites, and preharvesting fresh produce from farms irrigated with the sampled water. All samples were collected from Cairo and Giza governorates, Egypt. PCR analysis was carried out with positive isolates using the α-toxin gene. Sequence analysis of the gene of C. perfringens isolates was performed using the neighbour-joining approach. Bootstrap analysis was executed with 1,000 resamplings.

Results: 174 C. perfringens strains were isolated with a 49.01% prevalence. The highest prevalence of C. perfringens in apparently healthy animals was found in sheep (65.45%) followed by goats (58%), buffaloes (55%), and cattle (47.1%). Its prevalence in humans being in contact with these animals was 47.5%. The bacterium’s isolation from the soil and irrigation water was achieved in 40% and 31.7% of samples, respectively, posing a risk, particularly when the water and soil contact food in the field, shown by the fresh produce isolation of 40%. A significant relationship between the prevalence of C. perfringens in animal and environmental samples was identified (P < 0.05). A significant relationship was identified neither between animal species and C. perfringens prevalence, nor between the environmental source and C. perfringens prevalence (P > 0.05). All isolates were positive for the α-toxin gene by PCR. The sequence analysis and the phylogenetic relationship of the α-toxin genes from different samples revealed that C. perfringens from faeces of apparently healthy cattle, buffaloes, sheep, and goats is a significant threat in places where it can contaminate the soil and water. In addition, the sequence of C. perfringens from humans suffering from diarrhoea was found in the same cluster with the sequence from cows, goats, and sheep.

Conclusion: The role of apparently healthy animals in transmitting C. perfringens to humans, either through being in direct or indirect contact via water or soil in the cultivation of vegetables and fruits, was demonstrated.

Open access

M. Harčárová, E. Čonková and Z. Sihelská

Abstract

The cereals are a suitable substrate for the growth of microscopic filamentous fungi. Micromycetes are capable of reducing the nutritional value of feedstuff and they can produce several mycotoxins. The most frequent genera of microscopic filamentous fungi are Fusarium, Penicillium, Alternaria and Aspergillus. The contamination by microscopic fungi and mycotoxins was determinated in 56 samples of feed cereals originating from the Slovak Republic. The most common genera of fungi detected in the feed cereals included: Alternaria (67.8 %), Fusarium (44.6 %), Penicillium (39.2 %), Mucor (30.3 %), Rhizopus (28.5 %), Cladosporium (21.4 %), Scopulariopsis (8.9 %) and Aspergillus (1.7 %). Deoxynivalenol was present in 24 samples (42.8 %) and zearalenone in 15 samples (26.7 %). The values of both mycotoxins did not reach the regulatory limits and thus they do not pose a risk to livestock nutrition.

Open access

Mohammad Rafiqul Islam Talukder, Moinul Hasan, Tasmia Akter Rosy, Farida Yeasmin Bari and Nasrin Sultana Juyena

Abstract

Introduction: The ovarian follicular dynamics, vaginal electrical resistance (VER), progesterone (P4) and oestrogen (E2) profiles were investigated during the oestrous cycle in four indigenous ewes.

Material and Methods: Daily VER values were recorded with a heat detector. The follicles were observed and measured by trans-rectal ultrasonography. Blood was collected daily for hormonal profiles.

Results: A significant variation in VER values (P < 0.05) in oestrus by ewes and position in the sequence of cycles was observed. Trans-rectal ultrasonography of ovaries revealed the presence of 2–4 waves of follicular growth. Study of hormonal profiles by ELISA revealed a positive correlation between E2 concentration and development of follicles and a negative correlation between P4 concentration and their development. The concentrations of oestradiol increased in oestrus and then decreased to a basal level. Follicular growth was accompanied by a rise in the concentration of serum oestradiol. Inversely, when follicles received the stimulation for ovulation, concentration of progesterone started to fall, but after ovulation, it climbed back to its peak and remained at this state until next ovulatory follicle reached its maximum diameter.

Conclusion: This study could help to set up a manipulative reproductive technique for improving genetic values in indigenous sheep.

Open access

A. B. Ayinmode and O. O. Falohun

Abstract

Cryptosporidium infections has been reported in several avian species including chickens, pigeons and game birds where these infections had been identified to cause either enteric or respiratory diseases. However, little data exists on the molecular characterization of Cryptosporidium species in ducks, especially those in frequent contact with humans. The aim of this study was to detect the Cryptosporidium species infecting domestic ducks in two major live bird markets. A total of 109 fresh faecal samples were collected from all the ducks available on sale in the two markets. The detection of Cryptosporidium species was conducted by microscopy. All positive samples were confirmed by the nested PCR amplification and the nucleotide sequencing of the 18S rRNA genes. The results demonstrated that the prevalence of Cryptosporidium infection in ducks using microscopy was 11.0 % (12/109). There was a higher prevalence 14.0 % (7/50) in ducks from Ibadan compared with those 8.5 % (5/59) obtained from Oyo town. All positive samples by microscopy were also positive using the nested PCR and the DNA sequencing of the secondary PCR products from the 18S rRNA genes which revealed the presence of Cryptosporidium parvum. This study revealed that natural infections of C. parvum may occur in ducks in close contact with humans and other domestic animals and therefore suggests that cryptosporidiosis in ducks may be of public health importance.

Open access

R. Vlčková and D. Sopková

Abstract

Yucca is an important source of biologically active substances such as steroidal saponins and stilbenes providing many beneficial effects when administered to humans and other animals. These substances offer a great potential in the prevention and treatment of current civilized diseases as well as to their: antioxidant, hypocholesterolaemic, anti-inflammatory, phytoestrogenic, pro-apoptotic, anti-proliferative, and anti-carcinogenic properties. This review focuses on the roles of two main yucca constituent groups and their ability to modulate ovarian functions and female reproductive performance. Both the biological activity of yucca substances and the mechanisms of their actions on ovaries are still incompletely understood. Thus, the direct effects of yucca extract on ovarian cells in animal models under in vitro conditions, as well as actions after yucca consumption will be discussed.

Open access

Myongha Jin, Yunyueng Jang, Taehyun Seo and Sang Heui Seo

Abstract

Introduction: Highly pathogenic Asian H5-subtype avian influenza viruses have been found in poultry and wild birds worldwide since they were first detected in southern China in 1996. Extensive control efforts have not eradicated them. Vaccination prevents such viruses infecting poultry and reduces the number lost to compulsory slaughter. The study showed the efficacy of inactivated H5 vaccine from the H5N8 virus against highly pathogenic H5N8 and H5N6 avian influenza viruses in chickens.

Material and Methods: Reverse genetics constructed an H5 vaccine virus using the HA gene of the 2014 H5N8 avian influenza virus and the rest of the genes from A/PR/8/34 (H1N1). The vaccine viruses were grown in fertilised eggs, partially purified through a sucrose gradient, and inactivated with formalin. Chickens were immunised i.m. with 1 µg of oil-adjuvanted inactivated H5 antigens.

Results: Single dose H5 vaccine recipients were completely protected from lethal infections by homologous H5N8 avian influenza virus and shed no virus from the respiratory or intestinal tracts but were not protected from lethal infections by heterologous H5N6. When chickens were immunised with two doses and challenged with homologous H5N8 or heterologous H5N6, all survived and shed no virus.

Conclusion: Our results indicate that two-dose immunisations of chickens with H5 antigens with oil adjuvant are needed to provide broad protection against different highly pathogenic H5 avian influenza viruses.