The morphology of the large intestine in birds is different. In addition to its nutritional role, because of the existence of lymphatic tissue, it plays an important immunological role. The present study was designed and conducted to expand the histological knowledge of the gastrointestinal tract in birds by evaluating the histomorphology of the cecum and colon at different ages. For this purpose, 36 ostrich chicks were selected in 6 age groups. These samples were selected from slaughterhouses around Tehran at the ages of one and fifteen days and one, three, six, and twelve months. In this study, it was found the epithelium of the cecum is pseudostratified and simple columnar, and the number of goblet cells increases with the age of the chickens. The muscularis mucosa at the base of the cecum was indistinct and thin, but clear at the apex of the cecum and colon. The thickness of the muscular layer increased with age the Auerbach plexus were mostly seen between the fibers of the longitudinal layer of the muscular layer. The lymphatic tissue was also observed in follicular shape in the lamina propria of the cecum from the age of six months. Based on the results, it can be concluded that in general, in terms of histomorphological features, the development of the large intestine in ostrich chickens is very similar to other birds, especially the Struthioniformes. However, the differences can be found in the condition of the muscularis mucosa and the distribution and timing of lymphatic tissue formation.

There are limited studies about nutrition of ostriches, and its role in the body’ s metabolic status. The aim of this study was to investigate the effects of different concentrate: alfalfa hay ratio on concentrations of blood protein and energy metabolites, electrolytes and activity of some enzymes of African domestic ostrich chickens at 8 and 10 month of age. Three treatments were as follows: 700g of concentrate plus 300g alfalfa hay (treatment 1), 650g of concentrate plus 350g alfalfa hay (treatment 2) or 600g of concentrate with 400g of alfalfa hay (treatment 3) per kg of diet. A total of 18 ostrich chickens, with average weight of 63 ± 3. 15 kg, were used in this experiment (6 birds per treatment). The treatment 1 had significantly higher blood glucose and lower uric acid levels compared with treatment 3 (P<0. 05). The treatment 3 also showed the lower enzyme activity of aspartate transaminase and cholesterol and LDL-C levels compared with treatment 1 (P<0. 05). With increasing age, the blood glucose level was decreased, whereas the urea level was increased (P<0. 05). Dietary treatment and age had no significant effects on values of total protein, albumin, globulin, alkaline phosphatase, alanine aminotransferase, gamma glutamyl transferase, triglycerides, HDL-C and VLDL-C (P>0. 05). From the results of this study, it could be concluded that the use of diet containing higher crude fiber and lower metabolizable energy (ME) in ostriches’ diet was particularly effective to improve the metabolic profile, especially plasma lipid profile, compared with diets containing lower fibers and higher ME.

Birds are routinely exposed to this fungus and only rarely become pathogenic and the lower respiratory tract is most severely affected by inhalation rout. There have been some recent reports about respiratory aspergillosis in ostrich (Kyoung 2001, Marks et al 1994). Aspergillus spp usually cause disease under condition of stress, immunosupression, and prolonged treatment with antibiotics or massive exposure to the microorganism. Clinical signs of aspergillosis in ostriches are weight loss, lethargy and dyspnea (Kyoung 2001). Other less common forms of aspergillosis in birds are encephalitis, ophthalmitis, osteomyelitis, dermatitis and systemic form (Fitzgerald & Moisan (1995). A fumigatus was isolated in some cases of respiratory aspergillosis (Campbell (1986). It has been reported that aspergillosis was observed in ostriches in the late 19th and early 20th centuries, but is relatively uncommon today (Terzich &. Vanhooser (1993). This is the first case report of aspergillosis due to A ftnigatus in Iran. The ostriches of this report had received chloramphenicol and enrofloxacin for a long time (45 days) so these drugs may have been the cause of the pulmonary aspergillosis.

Most highly pathogenic avian influenza viruses (AIV) emerge after field passage of non-pathogenic AIVs in birds. The outbreak of low-pathogenic H7N1 avian influenza virus in Italy during 1999-2000 followed by outbreak of highly pathogenic H7N1 avian influenza virus is one example in this regard. This experiment has been designed to investigate the effect of pre-infection of birds with LPAI on subsequent challenge with HPAI virus from the same outbreak. chickens were inoculated intranasally with LP H7N1 A/CK/Italy/1279/99 avian influenza virus at 3 weeks of age and two groups of 10 birds were challenged at 18 and 24 weeks of age with homologous HP H7N1 A/ostrich/Italy/984/00 virus from the same outbreak. The overall mortality of birds was 60%; pre-infected challenged birds died 4-17 days post challenge (PC), while naive birds died 2 days PC. Pre-infected birds showed peritonitis, salpingitis and oophoritis in necropsy and histopathology showed very severe necrosis of the spleen, pancreas, moderate to severe necrosis of the liver and inconsistent degeneration and inflammation of the lung. Necropsy of the control bird showed petechial haemorrhage on the heart, caecal tonsils and the tracheal mucosa.

In ostriches, mycoplasmas are generally, related with respiratory diseases and causes rhinotracheitis, airsacculitis and inflammation of the upper respiratory tract. The aim of current study was to isolation of pathogenic mycoplasmas in ostrich farms of Iran using PCR and culture methods. Materials and Methods: In this study, 100 samples were taken from lung, trachea and air sacs of ostriches with respiratory disease at slaughter time. Samples was evaluated by culture, rapid serum test and PCR. Results and conclusions: The PCR tests results indicated 21.05% of samples was positive, which 7.89% and 14% was M. gallisepticum and M. synoviae, respectively. In culture method, 6.14% of samples was positive in view of M. gallisepticum and 7.01% of M. synoviae. Also according to clinical evaluation highest rate of positive cases was in lungs, air sacs, and trachea, respectively. According to prevalence of poultry mycoplasmas in ostriches, it is essential to exact evaluation of their pathogenesis in ostriches, to determine the importance of prevention.

Th e present study was carried out to determine the development of pancreas in ostrich embryo. For this purpose ostrich embryos obtained on 10, 13, 16, 22, 26, 30 and 36 days of prehatching and 1 day of post hatching life. Th e specimens were stained with haematoxylin eosin [H&E], Gomori and Toluidine blue, and then were explored by light microscopy. Th e Results showed the primitive pancreas near the liver and duodenum on day 13. Histological observations showed that the pancreas was consisted of undiff erentiated epithelial cells, connective tissue, non-organized ducts and blood vessels. On day 16, pancreas was composed of two dorsal and ventral lobes with the same structure of day 13. Th e zymogen granules were evident in developed acini on day 22. By aging the level of connective tissue and ducts were decreased and the acinar cells were increased. Pancreatic islets were determined on the day 1 aft er hatching.

Since the implementation and development of a productive activity would be recommendable and can be developed after identifying. its economic aspects, and because the accuracy of implementation of projects in different fields is extremely important, especially in animal husbandry, economic evaluation of production units in order to evaluate the performance of units is enjoy a special place. In this research effort were given to the examination of economic evaluation of ostrich fattening breeding units in Hamadan province, according to the present sitnations. units selected in this study using stratified sampling and data collected through interviews and questionnaires of ostrich farmers in Hamadan. Indices studied in this research were net present value, benefit to cost ratio and internal rate of return. The results showed that the net present value of ostrich fattening breeding units was positive and greater than zero, the benefit to cost ratio was greater than one internal rate of return was high. In other words, the construction of ostrich fattening breeding in Hamedan Province is economically beneficial.