BACKGROUND: Coronaviruses have a wide range of host tropism causing respiratory, enteric and central nervous system diseases in pigs, cats, dogs, rodents, cattle, avian species and human. Coronaviruses undergo genetic mutations and recombination at high rates which make them able to infect a wide range of host species from different geographical locations. According to the possible existence of gammacoronavirus in Iranian bird population including pigeons and lack of information about virus prevalence, isolation and molecular characterization of pigeon coronaviruses are needed. OBJECTIVES: The present study was conducted to detect avian coronavirus in flocks of Tehran province.               METHODS: samples were randomly collected from 25 pigeon flocks of Tehran province (250 tracheal swabs and 250 cloacal swabs, 20 specimens from each flock) between 2014-2015. The viral RNA was extracted from swab samples and RT-PCR reaction was run using the QIAGEN one-step RT-PCR Kit with primers targeting nucleocapsid (N) gene and 3’ untranslated region (3’-UTR) of gammacoronavirus. RESULTS: Gammacoronavirus was detected in one out of 25 (4%) flocks. CONCLUSIONS: The results of this study approve the presence of  gammacoronaviruses  in pigeon population and help to complete the map of  epidemiology of the virus in Iran. According to the low prevalence rate of coronavirus in pigeons, samples should be collected from pigeons showing respiratory or enteric signs of disease or from pigeons having contact with other birds or those which are housed near poultry farms.

Fifteen samples of fish fillets were collected from different Egyptian markets to detect the residues of some heavy metals in them. The average weights of fish fillets samples were 250g. The samples were separately packed in polyethylene bag and sent to the laboratory for preparation and analysis. All equipment surfaces and utensils which used in this study were thoroughly cleaned with detergent, rinsed with water, dried and then rinsed with 2-propanol solution. The samples were stored at –2C prior to analysis. The mean levels of lead and cadmium in fish fillets collected from the Egyptian markets were 1.51  0.34 and 0.60 0.0.25 mg/kg; respectively. The concentration of lead in fish muscle were less than the permissible heavy metal limit in fish meat (2.0 mg kg) as stated by the World Health Organization, also these results were in line with the corresponding EU regulations. However the level of cadmium concentration was over than the heavy metal limits in fish meat (0.5 mg/kg) for the World Health Organization.

This study was carried out on 68 randomly collected chickens located at Ras Sedr Research Station, Desert Research Center, 68 serum samples were examined serologically by complement fixation test (CFT). Twenty out of 68 (29.91%) had antibodies against Chlamydophila psittaci . Ten blood samples of the serologically positive cases were subjected to polymerase chain reaction (PCR) and showed positive results for Chlamydophila psittaci at 119 bp. Therefore PCR was found to be reliable, rapid, sensitive and specific technique for the detection Chlamydophila psittaci in birds. Serologically positive birds did not show any clinical symptoms of disease, but they were in contact with sheep and goat that showed previous abortion and were positive for C. abortus. It is recommended to avoid breeding of chickens with other animal species in the same yard because chickens become asymptomatic carrier with shedding of Chlamydophila psittaci in their feaces and respiratory discharges.

Peroxidase labeled immunoglobulins to camelpox virus (CPV) were prepared for use in various techniques of ELISA. Ten rabbits and three goats were inoculated with a mixture of camelpox virusand Freund’s adjuvant. Sera were pooled separately on the 10th day post the last inoculation and immunoglobulins were precipitated using saturated ammonium sulphate. The globulins were 2.8 g/dl and 2.5 g/dl for rabbits and goats respectively and used for peroxidase conjugation. The peroxidase labeled immunoglobulins were titrated and evaluated using direct solid phase ELISA, double antibody sandwich ELISA and dot immunoblot ELISA. The prepared conjugates gave specific and clear positive reactions till the dilution of 2000 and 1500 for rabbits and goats immunoglobulins respectively. The prepared labeled immunoglobulins could be successfully used in detection of camel pox viral antigen of local virulent and standard vaccinal strain of the virus using various ELISA techniques.

A total of one hundred samples of marketed fish farm; 25each of tilapia (Oreochromis niloticus), Mugil cephalus, Carp (Silver) and fry; were collected from different localities at Al- Behera and Kafr El-Shakh Provinces. The samples were examined for detection of testosterone hormone by Thin Layer chromatography (TLC) as well as it was quantitatively assayed by Radio-Immuno-Assay (RIA). The obtained result revealed that the testosterone residues were detected in flesh of farm fish of Tilapia (Oreochromis nilotocus) and Carp (Silver), each constituting 24% and 4 %; respectively but it could be failed to detect in each of Mugil cephalus and fry. The hormonal residues of testosterone was ranged from 3.25 to 34.9 ng/g with mean value 4.22±1.1 ng/g in positive samples of Tilapia, while only one sample of Carp showed 22.0 ng/g, Mugil cephalus and Fry showed no detectable level of hormonal residues. The public health significance of detectable levels was discussed as well as the recommendations to avoid health hazards from such fish were mentioned.

This study was carried out on 180 pregnant ewes located at Ras Sedr research station - desert research center, from 2003 to 2005. Twenty five cases of abortion were recorded and examined serologically by complement fixation test (CFT). 17 (68%) out of these 25, showed positive results against Chlamydophila abortus and 3(15%) out of 20 apparently healthy pregnant ewes were serologically positive. Due to the fact that both clinical signs and pathological findings are not specific in case of chlamydial infection and also due to the fact that CFT is accompanied by false positive reactions due to cross reactivity between chlamydial species, five samples from serologically positive aborted dams were subjected to polymerase chain reaction (PCR). They revealed positive results for Chlamydophila abortus at 119 bp. Therefore, PCR is proven to be reliable, rapid and specific diagnostic technique in thediagnosis of chlamydial infection.

The aim of the study was to determine the effect of the vitamins, omega-3 polyunsaturated fatty acid and minerals in the supplement Toryum administered before and during oestrus synchronisation on some fertility parameters of ewes during the non-breeding season. The experimental animals were clinically healthy Pirlak ewes, 55–75 days postpartum, aged 2–4 years and weighing 40–50 kg. A sponge was inserted into the vagina for 10 d (G1, n = 30; G2, n = 30) or 14 d (G3, n = 30; G4, n = 30) for oestrus synchronisation, and on the day of removal, 400 IU equine chorionic gonadotropin was injected. Toryum soft capsules were administered individually (1 capsule/ewe p.o.) to G1 and G3 ewes seven days before the sponge was inserted and on the day it was removed. Oestrus detection was started 12 h after sponge removal. Pregnancy was diagnosed by transrectal ultrasonography on the 30ᵗʰ day after mating. The pregnancy rate was statistically different between G1 and G4 (P < 0.05). The onset of oestrus was statistically different (P < 0.001) between the 10-d groups (G1 and G2) and the 14-d groups (G3 and G4). The litter size and oestrus, conception, lambing, multiple birth, and survival rates were not significantly different between the groups (P > 0.05). Toryum administered to Pirlak ewes during progesterone-based oestrus synchronisation protocols during the non-breeding season may increase pregnancy rates. The relationship between Toryum and fertility parameters in ewes would be better understood by comprehensive studies.

The plate counting method widely used at present to discern viable from non-viable Brucella in the host or cell is time-consuming and laborious. Therefore, it is necessary to establish a rapid, simple method for detecting and counting viable Brucella organisms. Using propidium monoazide (PMA) to inhibit amplification of DNA from dead Brucella, a novel, rapid PMA-quantitative PCR (PMA-qPCR) detection method for counting viable Brucella was established. The standard recombinant plasmid with the target BCSP31 gene fragment inserted was constructed for drawing a standard curve. The reaction conditions were optimised, and the sensitivity, specificity, and repeatability were analysed. The optimal exposure time and working concentration of PMA were 10 min and 15 μg/mL, respectively. The correlation coefficient (R²) of the standard curve was 0.999. The sensitivity of the method was 10³ CFU/mL, moreover, its specificity and repeatability also met the requirements. The concentration of B. suis measured by the PMA-qPCR did not differ significantly from that measured by the plate counting method, and the concentrations of viable bacteria in infected cells determined by the two methods were of the same order of magnitude. In this study, a rapid and simple PMA-qPCR counting method for viable Brucella was established, which will facilitate related research.

White sturgeon iridovirus (WSIV) disease is caused by a virus of the eponymous family and is mostly triggered by stressful environmental conditions, i.e. high rearing density, excessive handling, or temporary loss of water. The aim of this study was to develop the most effective diagnostic method for quick and efficient confirmation or exclusion of the presence of WSIV. A total of 42 samples (spleen, gills, intestine, skin, kidney, and brain) were collected from eight sturgeon (Acipenser gueldenstaedtii and A. oxyrinchus) aged ≤5+ farmed or caught between 2010 and 2014 in open waters (Dąbie Lake and Szczecin Lagoon). They were tested for WSIV presence using conventional PCR, qPCR, and in situ hybridisation (ISH). In gross examination, all fish appeared to be healthy. Neither species showed clinical signs typical of WSIV infection. In the majority of cases, fragments of iridoviral DNA were found using molecular methods in the kidneys, and also in the liver, gills, and skin. The detection rate using ISH was 47.37% and most commonly the brain and kidney tissues were positive. The most efficient of the methods used was real-time PCR, with 100% effectiveness in detection of WSIV DNA. The study demonstrates the capabilities for WSIV diagnosis available to sturgeon farmers and water administrators, indicating useful methods of adequate sensitivity as well as organs to sample in order to achieve the highest probability of viral detection.

The aim of the study was to determine the transmission potential of carp edema virus (CEV) and koi herpesvirus (KHV) introduced to Europe by the invasive round goby (Neogobius melanostomus). A total of 70 round goby specimens were collected from the Szczecin Lagoon, Poland, and locations in Germany in the third and fourth quarters of 2018. The fish were analysed to detect KHV and CEV by PCR. Six fish specimens were positive for the presence of KHV, while none of the gobies examined showed the presence of CEV. The CEV genome was detected in the goby specimens from Germany and from Poland. Considering the high pace of the spread of the round goby and its effectiveness in acquisition of new ecological niches, it should be kept out during refilling of carp ponds. Further studies should focus on experimental cohabitation of CEV-infected round gobies and specific-pathogen-free (SPF) carp to investigate the potential for active virus transfer.