Study on the antioxidant status of rats experimentally infected with Trypanosoma evansi.

The antioxidant status of rats experimentally infected with Trypanosoma evansi isolated from a camel was studied using established parasitological, haematological and biochemical methods. The results indicated that infections in all rats resulted in a fulminating parasitaemia. Changes in blood parameters in T. evansi-infected rats indicated leukocytosis and a macrocytic hypochromic anaemia. A degree of anisocytosis was also observed. The activities of plasma glucose-6-phosphate dehydrogenase and glutathione peroxidase in whole blood of infected rats were significantly higher (p<0.05 and p<0.001, respectively) compared with control. No statistically significant difference was observed in the activity of superoxide dismutase in infected and control rats. Results obtained indicated that trypanosomosis caused oxidative stress and induced antioxidant enzymes.

Concurrent infection with bovine leukaemia virus and Theileria annulata in a Friesian calf.

Concurrent infection with bovine leukaemia virus (BLV) and Theileria annulata was diagnosed in a Friesian calf about 6 months of age at a dairy farm at the Qassim region of central Saudi Arabia. The disease ended fatally with signs of liver and heart failure. There was anorexia, pyrexia, anaemia, generalized oedema and jaundice. Haematology showed low RBC counts, PCV percentage and haemoglobin concentration and WBC counts. Lymphocyte differential was high. Examination of blood smears stained with Giemsa's stain showed the presence of piroplasms in red blood cells. Autopsy showed enlarged lymph nodes and lymphosarcoma lesions in the omentum and the heart. There was hydroperitoneum, hydropericardium and hydrothorax. The liver was pale yellow and friable. Impression smears from sliced lymph nodes and stained with Giemsa's stain showed presence of Koch's blue bodies in lymphoblasts. Histopathological examination revealed fatty degeneration of hepatocytes and pleomorphic lymphoblasts and giant cells in lymph nodes. Lymphoblasts infiltrated the omentum and heart tissues. Amyloid was found around blood vessels in the liver, kidneys and lymph nodes. BVL infection was diagnosed by demonstrating antibodies against the virus in serum using agar gel immunodiffusion and was confirmed with ELISA.

Antioxidant levels in tissues of young and adult camels (Camelus dromedarius).

In this study, we measured the concentration of some antioxidant substances in erythrocytes hemolysate, liver, kidney and brain in young and adult camels. It has been found that the activity of the antioxidant enzymes glutathione peroxidase (GSH-Px), catalase (CAT), superoxide dismutase (SOD) and the concentration of glutathione, ascorbic acid and alpha-tocopherol are high in both young and adult camels. GSH-Px and CAT activities were higher in adult camels than in the young whereas no significant difference in the activity of SOD between young and adult camels was noticed. Glutathione was present in all tissues studied. Ascorbic acid was found to have significantly higher values in young camels. From this study it could be concluded that, as in other mammals, camel tissues contain a powerful antioxidant system. The liver has the highest contents of antioxidants and antioxidant enzymes indicating that it plays an important role in pro-oxidants detoxification. Age has a variable effect on the antioxidant system in camels.

The occurrence of Thysanosoma actinioides Diesing, 1834 (Cestoda: Anoplocephalidae) in a Najdi Camel in Saudi Arabia.

The fringed tapeworm Thysanosoma actinioides was recovered from the liver of a Najdi camel (Camelus dromedarius) slaughtered in central Saudi Arabia. T. actinioides is recorded for the first time as a parasite of old world camels.

An outbreak of neurofilariosis in young goats.

An outbreak of cerebrospinal microfilariosis in 23 kids, representing a whole kid crop, occurred on a farm in Qassim, Central Saudi Arabia. The morbidity and mortality rates were 100%. Clinical signs, in kids from the fourth to sixth week of age, manifested as weakness in the hind legs followed by incoordination of movement and feet dragging. Seven to ten days later, the hind legs were completely paralyzed, and within a week the front legs were also paralyzed. The animals continued to feed, drink and suckle normally, and were in good health. Paralyzed kids were helped to suckle by the farm attendants. With time, loss of control of motor functions occurred and the ability to hold the head in upright position was lost, ability to eat or drink was lost. The infected kids health deteriorated and they eventually died. Two dead kids were postmortemed. With the exception of a meningeal haemorrhage seen in one kid, no obvious macroscopic lesions were seen in any of the autopsied animals. Histopathological examination of the spinal cord and brain showed different microfilaria of different sizes between the meninges and the nervous tissue. This indicated that development of the parasite occurred in the nervous tissue. The larger microfilaria contained black deposits, most likely to be digested blood, in their guts. It is likely that the parasites are haematophagus. The main lesions caused by the microfilaria were migratory traumatic haemorrhagic tracts in the spinal cord and the brain. These sometimes contained parts of the microfilariae. In the brain malacic lesions and sporadic aggregates of lymphocytes were also noted.

Parasitological and clinico-pathological profiles in friesian cattle naturally infected with Theileria annulata in Saudi Arabia.

Clinico-pathological profiles were studied in adult and young Friesian cattle naturally infected with Theileria annulata in the Qassim Region, Saudi Arabia. Sixty-two clinical cases of T. annulata infection in adult and young Friesian cattle were diagnosed during the period from August 1999 to July 2000. Symptoms observed were marked fever, swelling of superficial lymph nodes, inappetance, tachycardia, dyspnoea and weakness. The most prominent gross pathological features were jaundice, petechial and ecchymotic haemorrhages involving mucosal and serosal surfaces of many organs as well as body fat. A number of young and adult Friesian cattle undergoing lethal T. annulata infection developed lymphoma-like lesions in a manner similar to that of T. parva. The main histological findings were necrosis and severe lymphocytic infiltration. The spleen, lymph nodes and Peyer's patches were devoid of typical lymph nodules.

Biochemical profiles in Friesian cattle naturally infected with Theileria annulata in Saudi Arabia.

The biochemical parameters were studied in adult and young Friesian cattle naturally infected with Theileria annulatta in the Qassim Region, Saudi Arabia. Forty-three clinical cases of tropical theileriosis were studied, together with 40 clinically healthy Friesian cattle. Cattle clinically infected with T. annulata had significantly lower serum total protein, albumin, globulin, creatinine, calcium, phosphorus, magnesium, potassium, iron and copper concentrations and significantly higher AST activity and bilirubin concentration than the healthy cattle.

Haematological profiles in pure bred cattle naturally infected with Theileria annulata in Saudi Arabia.

The Abbott Cell Dyn 3500 haematology analyzer was employed to study haematological parameters in 41 adult and young Friesian cattle naturally infected with Theileria annulata in the Qassim region of Saudi Arabia. Comparison was made with clinically healthy adult and young Friesian cattle. Changes in blood parameters in T. annulata-infected cattle indicated severe macrocytic hypochromic anaemia, panleukopenia, lymphocytopenia, eosinopenia, neutropenia and thrombocytopenia but no reticulocytosis.

Diagnosis of Trypanosoma evansi in Saudi Arabian camels (Camelus dromedarius) by the passive haemagglutination test and Ag-ELISA.

The passive haemagglutination test and Ag-ELISA were employed to monitor antibody titres and antigenaemia levels in 4 Najdi camels experimentally infected with Trypanosoma evansi. The two tests were also used to determine the prevalence of trypanosomiasis in a total of 218 Najdi camels in the Gassim region, Central Saudi Arabia, during the period from October 1992 to September 1993. Trypanosoma evansi antibodies in the experimentally infected camels rose after 14-21 days and reached a maximum of between 1:64 and 1:128 by the 12th week post infection. Circulating antigens were detected in the experimentally infected camels one week post infection and antigenaemia levels fluctuated but generally remained above preinfection OD values. The results obtained from the field survey showed that 5.5% of the sampled camels were parasitologically positive for trypanosomes, while 19.7% were serologically positive by the passive haemagglutination test and 13.8% by Ag-ELISA. No significant age difference in seropositivity was observed in the tested camels.

The haematological and biochemical effects of the gastrointestinal nematodes prevalent in camels (Camelus dromedarius) in central Saudi Arabia.

Coprological examinations on 1200 Najdi camels (Camelus dromedartus) in the Gassim region of central Saudi Arabia between October 1992 and September 1993 revealed the presence of strongyle-type, Nematodirus and Strongyloides eggs. In addition, examination of the gastrointestinal tracts of 240 camels slaughtered in different abattoirs in the Gassim region from March to August 1994 revealed 11 species of helminths. Infection with gastrointestinal trichostronglyes resulted in normocytic, normochromic anaemia. Adult infected camels showed leukocytosis, a decrease in total serum protein concentration and increases in blood urea concentration and in serum creatine phosphokinase activity.

The effect of multiple transfers of immune serum on maturing Schistosoma bovis infections in calves.

To investigate the role of humoral factors in immunity, serum from cattle with naturally acquired immunity to Schistosoma bovis was injected intraperitoneally into calves that had been infected 4 weeks earlier with 10,000 S. bovis cercariae. Serum was injected weekly until 12 weeks post-infection to a total of 4,500 ml per calf and controls received normal serum or saline. No significant difference in worm or in faecal or tissue egg counts were seen in the three groups of recipients in spite of the observation that the serum donors had proved highly resistant to experimental challenge. In a second experiment, pre-infection or 4-, 8- or 12-week post-infection serum from donors given a single experimental infection with 10,000 S. bovis cercariae was injected intraperitoneally into groups of calves that had been infected 4 weeks earlier with 20,000 S. bovis cercariae. Injections were given weekly up to week 10 post-infection to a total of 2000-3500 ml serum per calf. In calves injected with immune serum there was a reduction in faecal and tissue egg counts and in the numbers of worms recovered as compared with the controls. In recipients of 8- and 12-week serum the reductions in faecal and tissue egg counts were higher than those in worm recovery, suggesting that 8- and 12-week post-infection sera contained factors capable of causing, in addition to worm death, suppression of worm fecundity. This provides further evidence of the importance of fecundity suppression in immunity to schistosomiasis.

Toxic effects of Crotalaria saltiana in mice.

Dry Crotalaria saltiana shoots were fed to strain ASL mice at 50, 10 and 1% of the diet. Feeding of Crotalaria shoots at 50 and 10% produced toxicity and death after 7 to 29 days. The signs of Crotalaria poisoning were inappetence, dullness, dyspnea and recumbency. The main lesions were necrosis, portal fibroplasia and hemorrhage in the liver, pulmonary congestion and emphysema, focal catarrhal enteritis, and degeneration of the cells of the renal tubules.

Effects of Crotalaria saltiana on Nubian goats.

Ten Nubian goats were given daily oral doses ranging from 0.5 to 10 g/kg/day of the fresh shoots of Crotalaria saltiana; they died at various times after dosing. The main signs of Crotalaria poisoning were dullness, dyspnea, inappetence, loss of condition and arching of the back. An increase in the concentration of ammonia, in the activity of GOT, and a decrease in total protein, calcium and magnesium were detected in the serum. The main pathological changes were hemorrhages in the lungs, heart and spleen, focal catarrhal enteritis, hepatic portal fibrosis, dilatation of the renal tubules and straw-colored fluid in the peritoneal cavity.