Although Theiler became internationally known for his pioneering veterinary research a distant century ago, there are probably few veterinary researchers today who have not heard of him. Onderstepoort, the research institute he created, is equally well, if not even better, known. Moreover, the name Onderstepoort is not only associated with his institute but also with the only South African faculty of veterinary science, another Theiler 'baby'. The purpose of this presentation is to determine why this was so, and to what extent the fame was justified. Was it due to the 'Spirit of Onderstepoort' sometimes referred to by Theiler in the early as well as later stages of his career, or was there perhaps more to it, and what was Theiler's share in the development of that spirit, that fame

The studies were carried out on 32 rams of the ossimi breed (270 days of age). Sixteen rams (group 1) received a ration containing 0.2 ppm. Se , and 30 mg vit.E, the other 16 rams (group 2) received 0.5 ppm. Se, and 50 mg vit.E/kg feed mixture .The feeding test was conducted from 270 days until 360 days of age. During the experiment the rams were subjected to live evaluations, i.e. testes circumference, libido level, semen characteristics, as well as selenium concentration and glutathione peroxidase (GSH-Px) activity in blood serum and seminal plasma. Routine macroscopic and microscopic analyses of semen quality were accompanied by measurement of Se content and GSH-Px activity in blood and semen. The Se concentration in blood plasma, seminal fluid and spermatozoa was measured by fluorometric method, while the GSH-Px activity by method based on NADPH - coupled reaction .Comparing the results in animals of both groups , it was clear that the all were in good health conditions as ascertained by clinical examination. No significant variation was detected in body weight of animals of both groups. Significant elevation (p<0.05) in the values of semen conc., semen conc./ ejac , semen motion , sperm motility / ejac.as well as total sperms count were observed in animals of group 2 as compared to those of group 1 .

Forty five, 21-day-old balady chick were used in this experiment. Chicks were divided into three equal groups. The 1st group used as control. The 2nd and 3rd groups were supplemented with lead (Pb) acetate (1500 ppm) in drinking water but the latter group received ration containing 20% barley. Blood samples were collected from the wing vein after 1, 2 and 3 weeks. RBCs count Hb concentration and PCV were significantly decreased in group II during the experimental period. RBCs indices showed a significant decrease in MCH and MCHC in group II after 2 and 3 week of experiment. Leukogram showed heteropenia and moncytopenia. Total protein values showed significant decrease in group II due to decrease in serum albumin level after 2 and 3 week of experiment. Significant increase in activity of liver enzymes AST & ALT and serum uric acid were observed in group II after 3 weeks of experiment. Measurement of serum level of malondialhyde (MDA) revealed a significant increase in group II after 2 weeks of experiment while the total antioxidant capacity (TAO) showed significant decrease in group II after 2 and 3 weeks of experiment. Results of the lead residues in the experimental groups revealed that lead residue in muscle, liver and kidney were rise in group II compared with groups I and III.

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.

Two fish pathogens, namely Listonella anguillarum (Vibrio anguillarum) and Vibrio vulnificus, which were beta-haemolytic, hemagglutinating with 1% D-mannose and hydroxamate siderophore producer were used in this study. The extracellular products (ECPs) of both species were of high enzymatic and haemolytic activities. SDS-PAGE analysis of ECPs of L. anguillarumand V. vulnificus revealed 4 band (20.7 to 47.5kDa) and 2 bands (30.1 to 46kDa) respectively. The cumulative mortalities in O. niloticus produced by crude ECPs of L. anguillarum (0.2ml/fish; 2.4mg protein /ml) and V. vulnificus (0.2ml/fish; 1.6mg protein /ml) were 90% and 80%. Heat treatment of ECPs of L. anguillarum and V. vulnificus at 56°C for 30 min reduced the mortalities to 30% and 20%, respectively. LD50 values in O. niloticus using crude and heat treated ECPs of L. anguillarum were 1.7 and 3.9 ^g protein/g fish; while those of V. vulnificus were 1.34 and 2.8 ^g protein /g fish, respectively. Injection of levamisole at a dose of 5mg/Kg fish, concurrently with ECPs of L. anguillarum and V. vulnificus resulted in subsidence of the mortality percentages from 90 to 40 and from 80 to 30, respectively. Ten laying hens were immunized with ECPs of L. anguillarum for preparation of specific egg immunoglobulins. The total protein content of IgY preparations collected from eggs of hens immunized with ECPs of L. anguillarum reached its peak 2 weeks post 3rd booster dose (3.820 ± 0.0700 g/dl). The molecular weight of separated protein bands of IgY preparations ranged from 183-191kDa. Fish injected (I/P) with specific anti ECPs IgY of L. anguillarum (4 mg/ fish) followed by I/P injection of ECPs of L. anguillarum (0.2 ml/fish; 2.4 mg protein /ml) showed a 10% mortality rate, while those challenged after receiving specific anti ECPs (100 mg/ kg B.W. orally) showed no mortalities.

Monthly total body tick collections from 13-20 camels were conducted for 2 consecutive years (2000-2001) in Northern Sudan. Tick populations were correlated with locality, season, predeliction site, sex and coat colour. Hyalomma dromedarii was found to be the predominant (89 %) tick species infesting the camels. Other tick species found in very low numbers were Hyalomma impeltatum (7.7 %), Hy alomma anatolicum anatolicum (3.3 %), Hyalomma truncatum (0.29 %), Hyalomma marginatum rufipes (0.25 %), Rhipicephalus praetextatus (0.30 %) and Rhipicephalus sanguineus group (0.09 %). Nymphs of the genus Hyalomma were collected in significant numbers. Adult ticks significantly preferred to attach to the lower parts of the camel's body for feeding while the nymphs preferred the back of the animal.