The development of thyroid glands of New-Zeland rabbits was studied in 28 fetuses (10-30 days) and 28 rabbits (3 days-5 years). The thyroid premordia appeared at the 12th day of gestation as 2 masses of cords and clumps of cells. The gland assumed the bilobed form with a narrow isthmus in between at the 18th day. Small primitive follicles with narrow empty lumina appeared in 14-day-old fetuses. True follicles were recorded in 20-22 days old fetuses while colloid was seen in the lumina of the central follicles at the 24th day. Light (C- or Parafollicular) cells were seen for the first time at the 12th day. With development of the follicles, C-cells appeared between the follicular cells and some of them come in contact with colloid. The ultimobranchial body (UBB) was observed in 20 days old fetuses close to the thyroid anlage and entered into its tissue at the 22nd day. Later on, it gave thyroid-like follicles or ultimobranchial cysts. With the electron microscope (EM) follicular cells of earlydeveloping fetuses were not yet differentiated. They contained few ill-developed rough endoplasmic reticulum (rER) and mitochondria. The organelles became well developed and the cells started to secrete colloid in full term fetuses. The maximum rate of secretory activity was achieved in the glands of adult rabbits. Changes in the thyroid glands during the postnatal life up to 5 years of age (age of senility) were followed up and described.

Elevated rectal temperature, mucopurulent nasal discharge, mortalities and abortion of pregnant ewes were the main clinical abnormalities recorded in sheep flocks at Seedy Salem Village, Kafr Al-Sheikh Governorate, Egypt following their vaccination by the attenuated Rift Valley vaccine. Meanwhile, 45 of the farmers in the village showed variable findings suggestive for a RVF epidemic and 17 farmers died of haemorrhagic fever as reported by the World Health Organization, WHO (2003). Blood serum samples were collected from 78 humans and 86 sheep and tested for RVF antibodies. We found that, where 11 (12.94%) and 10 (19.30%) of sheep and human sera respectively were positive. The recent history of vaccination of such flocks using the attenuated RVF vaccine lead us to suggest that the used vaccine might be the source of such epidemic.

The objective of this study was to determine whether Bos taurus cattle differ form Bos indicus in their susceptibility to infection with the Muguga stabilate of Theileria parva and in their resistance to the resultant disease. Ten Friesians (B. taurus), ten improved Borans (B. indicus), ten unimproved Borans (B. indicus) and ten Zebus (B. indicus) born to dams from an East Coast fever (ECF) endemic area were inoculated with an infective dose50 dilution of T. parva Muguga stabilate 147. All the animals except one Friesian and one Zebu developed schizont parasitosis. All the improved Borans, nine of the Friesians, eight of the unimproved Borans and six of the Zebus developed a febrile response. Four of the improved Borans, four of the Friesians and three of the unimproved Borans died of theileriosis. No significant difference (P > 0.05) in the prepatent period occurred between the groups, but the Zebus had a significantly shorter duration of schizont parasitosis (P > 0.05) and took a significantly shorter time to recover (P > 0.05) than the other three groups. There was no significant difference in the two parameters between the other three groups. The study showed that three B. indicus breds and a B. taurus breed are equally susceptible to T. parva infection. However, Zebus born to dams from an ECF endemic area showed a better ability to control the course of disease than cattle from ECF free areas.

This paper focuses on the geographical distribution and habitats of Bulinus forskalii, the snail intermediate host of the conical fluke of equids, Gastrodiscus aegyptiacus as reflected by the 1 209 samples in the database of the National Freshwater Snail Collection of South Africa. The 362 different loci on record represent an extensive distribution in KwaZulu-Natal Province, the Limpopo Province, the coastal areas of the Eastern Cape Province and the south-eastern part of the North West Province. Although it was recorded from all types of water-body represented in the database, the highest percentages of samples were recovered from dams (30.4 %) and brooks (28.2 %). The majority of samples came from perennial habitats (59.1%), 60.7% from habitats with standing water, 54.0 % from habitats with clear water and 71.8 % from habitats of which the water was described as fresh. The majority of samples (39.5 %) were collected in habitats of which the substratum was recorded as muddy. The highest percentage of samples, by far (81.5 %), was collected in habitats that fell within the mean yearly temperature interval ranging from 15-20 °C. An integrated decision tree constructed from the data in the database indicated that temperature and type of water-body played a decisive role in determining the presence of B. forskalii in a given area. The results of experimental exposure to miracidia of a local strain of both Schistosoma haematobium and Schistosoma mattheei in the laboratory indicated that a local strain of B. forskalii was incompatible with both these strains of parasite. Research to clarify the role of B. forskalii in the transmission of both Calicophoron microbothrium and G. aegyptiacus in South Africa, is recommended.

The pharmacokinetic profile of difloxacin was investigated in camels after single intravenous and intramuscular administration of 5 mg kg-1 b.wt. After i. v. injection, serum concentration time curve was best described as two compartment open model. The distribution and elimination half lives (t0.5 (') and t0.5())) were 0.513± 0.01 h and 6.3±0.15 h. respectively. Difloxacin was distributed extravascularly with a volume of distribution (Vdss) 1.10 ± 0.035 l kg-1., and total body clearance (CLB) of 0.141+ 0.031 l kg-1 h-1. following intramusclar injection, peak serum concentration (Cmax) 2.59 ± 0.19 ug ml-1 attained after Tmax 3.05 ± 0.035 h. The absorption and elimination half lives (t0.5 (ab) and t0.5 (el)) were 0.95 ± 0.003 and 5.86 ± 0.33 h., respectively. The systemic bioavailablility (F) and the plasma protein binding were 87.95 and 23 %, respectively.

A total of 980 camels were employed in this study for evaluation of some diagnostic procedures used for diagnosis of camel trypanosomiasis. Clinical examination revealed that 180 (18.37%) camels showed sings of illness including, loss of body weight, anemia, abortion, decrease of animal production and edema in some parts of the body. Parasitological examination of camel’s blood smears revealed the presence of Trypanosoma evansi in 57 (5.82%) camels. ELISA detected 99 (63.06%) positive cases while suratex test identified 80 (50.96%) positive cases. Results of mice inoculation test for detection of Trypanosoma evansi among camels showed that 69 (43.95%) camels were positive. The present study clarified that suratex test was 100% sensitive for diagnosis of trypanosomiasis followed by ELISA (98.55%).

Hyalomma anatolicum anatolicum nymphs were collected from two localities in the Sudan: Eddamer in Northern Sudan and Wad-Medani in Central Sudan. They were allowed to moult to adult ticks, which were assessed for Theileria infection in their salivary glands using Feulgen stain. At Eddamer, 49.6 % of 123 ticks examined were infected with Theileria and the mean intensity of infection was 1.3 (i.e. the number of infected acini / number of infected ticks). At Wad-Medani, 8.6 % of 162 ticks were infected and the mean intensity of infection was 7.9. The prevalence of infection was higher in female than in male ticks at both localities. When adult H. a. anatolicum were applied onto two susceptible calves, both animals developed the severe form of theileriosis.

A single-tube duplex nested polymerase chain reaction (sdn-PCR) was developed for the detection of and discrimination between ovine herpesvirus-2 (OvHV-2) and alcelaphine herpesvirus-1 (AlHV-1). These viruses respectively cause sheep- and wildebeest-associated malignant catarrhal fever (SAMCF and WA-MCF). In the first step of the sdn-PCR, two primers with high annealing temperatures based on conserved regions of the tegument genes were used for DNA amplification. In the second step, two primer sets based on variable regions of the respective OvHV-2 and AlHV-1 genes and with annealing temperatures > 11 °C below the primers used in the first step, were used. Internal regions of different sizes from amplicons produced in the first step were amplified. This single-tube test obviates the need for two separate assays to detect both viral types, thereby reducing time, labour and cost.

An experimental study was conducted on 14 donkeys. The animals were classified into two main groups. The first group included 5 donkeys that are used for induction of duodenal, obstruction for determination of the different clinical and biochemical changes and for determination of the mean survival time after obstruction. The second group contained 9 donkeys that were used for the determination of proper time for surgical intervention. Results revealed that mean survival time after obstruction was 20-35 h and the critical time for surgery was 14-35 h.

In this study, Brucella abortus RB51 could be detected in the vaginal exudates of 5 out of 26 aborted cows following vaccination of three dairy cattle herds of 3810 animals including heifers and pregnant and non-pregnant cows by RB51 vaccine. Abortion associated with isolation of RB51 vaccinal strain from recently vaccinated cows in this study served as evidence that the vaccinal RB51 strain was the cause of abortion due to extensive bacterial multiplication and colonization in the uterus of vaccinated pregnant cows