Erythrograms determined from whole blood analyses and serum analyses for aspartate aminotransferase (AST), gamma-glutamyl transpeptidase (GGT) and alkaline phosphatase (ALP) activities, and iron concentration, were used in infected and uninfected cattle to determine the type of anaemia and degree of hepatic damage caused by Fasciola hepatica. Blood samples from 86 infected and 30 uninfected cattle were taken at slaughter. Haematological analyses revealed decreased levels of packed cell volume (PCV), haemoglobin concentration, mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) in infected compared with uninfected cattle (P < 0.05). A decrease in the concentration of serum iron was also observed in infected cattle compared with uninfected cattle (P < 0.05). Significant increases in AST, GGT and ALP activities were observed in cattle infected with F. hepatica when compared with uninfected cattle (P < 0.05). It was concluded that the anaemia observed in cattle infected with F. hepatica is a normocytic, hypochromic anaemia and the most important aetiology of the anaemia is the chronic blood loss due to the blood-sucking activity of the adult flukes and leakage of blood from the bile duct to the intestine, which results in iron deficiency. The increased activities of serum enzymes indicated chronic hepatic and bile duct injuries associated with chronic infection with F. hepatica.

Cryptosporidiosis is a zoonotic protozoan disease that affects the gastrointestinal tract of animals and humans. Diarrhoea as the most important indication of the infection leads to high economic losses in livestock industries and is a life threatening infection in immunocompromised individuals. In the absence of the effective drugs, vaccine has an effective role in the prevention of infection. For this purpose we developed a vaccine utilizing recombinant P23 protein and immunized pregnant cows four times from 70 days to parturition every 2 weeks. After parturition, each calf received his dam colostrum and challenged with 1 × 10(7) Cryptosporidium parvum oocysts at 12 h of age. Results showed that in contrast with the control group, the antibody titre in the sera and first milking colostra of the immunized cows significantly increased and calves fed hyperimmune colostrum did not show cryptosporidiosis signs. Moreover, enriched colostrum not only reduced significantly the amount of oocyst excretion but also delayed its onset. Our study showed that recombinant P23 protein could be used for passive immunization of newborn calves against Cryptosporidium parvum.

Partial gene sequencing for the bovine coronavirus at the World Genebank is available for many countries, which are distributed unevenly in five continents, but so far, no sequencing of strains has been recorded in Iran. One hundred ninety‐four stool samples from calves with diarrhoea less than one‐month old were collected from five different geographical regions of country in order to detect coronavirus and characterize it if coronavirus was found. Samples were screened for the presence of BCoV by using a commercially available ELISA kit. Furthermore, RT‐PCR was carried out on positive samples for confirmation of the presence of N and S specific genes. Sequencing and phylogenetic analysis was carried out following RT‐PCR tests. 7.2% of samples, were positive for BCoV and all stool samples from the South‐West, Northeast and West regions of Iran were negative. The results showed that all the strains of coronavirus identified in Iran were completely in independent clusters and that they did not stand in the same cluster as any of the strains identified in other parts of the world. The strains from Iran were quite different from strains in other parts of the world but from the point of similarity these viruses showed some similarities to the European strains, such as those found in France, Croatia, Denmark and Sweden.

A seroepidemiological survey to determine the prevalence of Crimean-Congo haemorrhagic fever (CCHF) virus among dairy cattle in Iran was carried out during 2006 and 2008. Blood samples were collected from 876 animals in five different provinces of the country. Sera were tested by a sandwich enzyme-linked immunosorbent assay (ELISA) for quantitative determination of antibodies to CCHF virus. Serological evidence of infection was noted in 52 (5.9%) of 876 dairy cattle. Antibody prevalence increased with age; 78.8% seroprevalence in cattle older than 3 years versus 21.2% in animals less than 2 years old. There was a difference between provinces representing north-east (11.7%) and east (2%) of Iran.

Tetanus is an acute, often fatal, infectious neuromuscular disease in all farmed mammals caused by Clostridium tetani . The disease is sporadic but outbreaks of tetanus have been described, as a result of wound contaminated with spores of C. tetani , which sporulates to the vegetative form and produce toxins. The present study reports an outbreak of tetanus in a sheep flock, shortly after ear tagging. Three sheep from a large flock (with a population of 1000 sheep) were presented with signs of: convulsion, limb stiffness, incoordination and trismus (“lock jaw”). There were wounds and scabs in most livestock where ear tags had been attached 1 week prior. Clinical examination revealed tachycardia, dyspnoea with dilated nostrils, mild fever, erected ear pinnae, teeth grinding, mild bloat, muscles rigidity, prolapse of third eyelid and anxiety. According to the history stated by the owner, the case fatality rate of the disease from the beginning was 50% during the outbreak. Necropsy did not reveal any significant finding. Gram‐positive bacilli with terminal spores representing C. tetani were isolated in anaerobic cultures which were taken from ear wounds. Procaine penicillin G was administrated at 20 000 IU/kg BW for 5 days, but antiglobulin was not available to treat affected animals. Mortality significantly declined one day after onset of treatment. In this report, the organism was probably introduced by contaminated instruments which were used for ear tagging of sheep. Wound exudation and adhesion following rubbing, created a favourable anaerobic condition for the spores to germinate with production of neurotoxin. Vaccination can protect animals against tetanus, but it does not preclude the need to apply standard hygienic principles when performing management procedures causing wounds. In pasture holding system, many pathogens are present in environment, so tetanus should be considered important in farm animals, because of its high fatality rate and the long course of convalescence.