This study sought to determine if sheep suffer neurological symptoms when fed Acacia angustissima leaves, and whether an equivalent amount of 70% acetone extract would have the same effect. In addition, the study tried to determine if treatment of leaves with 70% acetone would destroy the activity of A. angustissima toxins, and whether extraction with 70% aqueous acetone extract would separate two components of a toxic system. Twenty-five Menz lambs were randomly assigned to one of five treatments (1) A angustissima leaves as half the diet, 2) dried extract (70% aqueous acetone) of the same quantity of leaves, 3) a corresponding amount of residues, 4) a recombination of the dried extract and dried residue, or (5) a control diet containing no A angustissima leaves or extract fractions. All animals fed the leaves and the recombined fractions died or were euthanized when they were observed to be dying of severe neurological derangement. None of the other animals showed any neurological signs of impairement. The results of this study indicate that healthy, well-fed sheep can be poisoned by A angustissima, that the toxins are not destroyed by acetone or oven drying, and that severe neurological intoxication requires two components, which can be separated by acetone extraction.

Aqueous decoctions obtained from the galls of Guiera senegalensis were screened to determine their phytochemical composition and in vitro antiviral activity against fowlpox virus. In addition, we wanted to investigate the toxic effects, if any, of crude extracts in chickens. Steroids as well as cardiac glycosides not previously reported, an alkaloid, polyphenols and saponins were detected in the various fractions of organic solvents used for extracting the decoctions. Antiviral activity was determined by cytopathic effect inhibition assay in primary chicken embryo skin cells. The 50 % inhibitory concentration (EC50) was shown to be 15.6 µg/ml. Toxicity for cells was established by determining the 50 % cytotoxic concentration (CCy50). A value of 90 µg/ml and a selectivity index (CCy50/EC50) of 5.8 were obtained. In vivo studies of toxicity were performed in chickens that were dosed orally with decoctions of several concentrations for 2 weeks and then monitored for 3 months. No significant changes in several blood chemical parameters were obtained, except for a significant decline in SGOT levels in birds dosed with 100 mg/kg. These levels were nevertheless within the accepted normal range. The findings suggest that aqueous decoctions of galls from G. senegalensis are non-toxic for chickens when administered orally, even at a daily dose of 100 mg/kg for 14 days.

The development of thyroid glands of New-Zeland rabbits was studied in 28fetuses (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.

Evaluation of amitraz against ticks and mites infestation in cattle and sheep in comparison with diazinon and deltamethrin was performed. Amitraz showed over 95 % inhibition of oviposition and hatching of laid eggs at dilution of 1:500 while diazinon and deltamethrin produced around 90 % inhibition of oviposition at the same dilution. Fed ticks were more susceptible for all tested acaricides than the unfed ticks, where amitraz reached its full effectiveness (100 % kill of fed and unfed) 2 weeks after application while diazinon and deltamethrin produced over 90 % at the same dilution. Spraying application of amitraz 12.5 % resulted in 100 % tick control by day 5 and the effect was maintained for further 28 days whereas diazinon and deltamethrin were fully effective by days 9 and 13, respectively and their efficacy were maintained for 16 and 20 days, respectively. Spraying application of amitraz 12.5 % produced 100 % efficacy as no live mites were found on day 17 and maintained in full effectiveness till day 33 where respraying was needed. In conclusion, amitraz produced rapid detachment of ticks from animals; its residual effect was long and protected animals from re-infestation for 29 days and was able to eradicate psoroptes mite infestation in sheep.

To analyze the major outer membrane proteins (OMPs) of the sensitive or resistant Pseudomonas aeruginosa strains, the OMPs were separated from the cellular elements by sarcosyl extraction method. OMPs profiles were conducted by SDSpolyacrylamide gel electrophoresis. Amoxicillin clavulanic acid (AMC) sensitive P.aeruginosa serotype K showed four protein bands; 35.713, 31.159, 26.107 and 22.869 KD. While AMC sensitive P. aeruginosa serotype H showed three bands of 35.713, 27.164 and 23.174 KD. Whereas AMC resistant P. aeruginosa serotype G, that was positive for the blaTEM gene by the PCR, modified its protein pattern. It has five protein bands of 52.142, 38.525, 30.690, 27.164 and 22.569 KD. These findings suggested that blaTEM gene and the outer membrane protein barrier are contributed to the resistance to amoxicillin clavulanic acid in P. aeruginosa. To determine a possible relationship between the resistance of P. aeruginosa and the production of antibodies against its outer membrane protein, antibodies against OMPs of AMC sensitive and resistant P. aeruginosa strains were prepared in mice and evaluated by ELISA. Our results showed that there was no association between immunogenicity of the outer membrane proteins and resistance of P. aeruginosa to antibiotics.

Survival of the neonate relies on the integrated expression of appropriatebehaviours from both mother and young. In this study, the effect of birth difficulty on maternal and lamb behaviours and its influence on lamb survival was investigated in crossbred primiparous ewes (½ Finnish x ½ Rahmani). Assisted ewes spent significantly (P<0.05) less time licking (30.83±1.39 min/2 h) and nosing (24.25±1.79 time/2 hr) their lambs than unassisted mothers (38.52±2.96 min, 28.80±1.68 time/2 h) respectively. They were found to be more aggressive towards their lambs when attempt to suck (9.80±0.37, 12.90±0.84 and 10.50±0.50 time/2 h) when compared with unassisted one (8.00±0.40, 10.20±1.52 and 7.66±0.88 time/2h) respectively. Lamb behavioural development were found to be significantly (P<0.05) affected by birth difficulty with lambs that require assistance at birth even if they survive the birth process, they were slower to progress through the sequence of neonatal behaviours. These lambs were therefore at greaterrisk of not surviving to weaning (28.57% vs. 11.42). It could be concluded that ease ofdelivery was an important factor determining the subsequent behaviour of the lamb and ewe and hence lamb survival, thus manipulation of husbandry and breeding system to improve delivery will improve lamb survival

A total of 40 samples of beef and chicken luncheon (20 samples for each) were collected from different markets in Giza city. Samples were subjected to Mycological investigations. Beef luncheon were highly contaminated than chicken luncheon (3.1 x 103 /g ±0.3x 10³) and (4.0 x 102 /g ±0.2x 10² ) respectively . Seven mould genera were isolated from examined samples. The majority of which were Aspergillus (19.7% and 18.1%) and Penicillium (18.9% and 15.7 %), while, Mucor (7.1% and 4.7%), Cladosporium (4.7% and 3.9%) and other genera were also isolated from the same samples but in low percentages from beef and chicken luncheon respectively. The predominant identified Aspergillus species were; A. niger (18.7% and 14.5%), A. flavus (18.7% and 12.5%) and A. ochraceous (6.3% and 6.3%) in the two products respectively. The main identified Penicillium species were; P. citrinium (20.6% and 13.6%), P. expansum (11.4% and 13.6%) and P. verrucosum (6.8% and 6.8%) from the same products respectively. Examination for mycotoxin production revealed the detection of ochratoxin A at a higher level (mean 21.0 and 27.0 ng /kg) from 2 (10%) samples of beef luncheon and one (5%) sample of chicken luncheon, respectively. Aflatoxin B1 (mean 15.3 and 9.8 ng / kg) was detected in 4 (20%) samples of beef luncheon and 3 (15%) samples of chicken luncheon, respectively. Other mycotoxins (AFB2, AFG1, AFG2 and T-2) were detected but in minor levels. Public health significance of the identified mould species and the detected mycotoxins were discussed.

A penta-dog inactivated cell culture vaccine was prepared to protect dogs againstcanine distemper virus, canine parvovirus, canine adenovirus1, 2 and rabies virus.The potency of this vaccine was compared with that of single inactivated vaccinesprepared against each disease, in different groups of susceptible dogs. It was foundthat the protective dose of penta-dog vaccine (2ml) including the protective amounts of the five viral proteins resulted in full protection of vaccinated dogs against the challenge with virulent strain of the used viruses showing no antagonizing effect between each other with and no adverse postvaccinal reaction. So, the prepared inactivated cell culture penta-dog vaccine is a safe and potent vaccine for dogs which resulted in saving time, cost, and effort stress factors on animals and providing good immune statues.

The incidence of E. coli O157, Salmonella typhimurium, Listeria monocytogenes, and Yersinia enterocolitica were studied in some locally produced cheeses. Thirty samples of each kind of the cheese were tested for the presence of some pathogens, which are frequently associated with food born disease. E. coli O157: IMS; Listeria monocytogenes were enumerated on modified Oxford agar; Salmonella was enumerated using standard procedures from Dynal manual using anti-Salmonella antibodies. Y. enterocolitica was enumerated on Yersinia selective agar base. Romano and processed cheese were found to be free from all tested pathogens but Kareish and Feta cheese were found to harbor E. coli and Y. entertocolitica. The results indicated the presence of some food borne pathogens in our food supply. Certain types of locally produced cheese still pose a significant health threat for the consumers. The finding of this study warrant the need for educational programs for dairy producers about the risks associated with consumption of certain cheeses manufactured from raw or insufficiently heated milk.

In this study a total of 120 diarrheic buffalo calves were examined clinically andbacteriologically was investigated. The role of E. coli in diarrheic buffalo calves. E.coli, could be isolated from 31 (25.80%) calves. K99 antigen could be detected in(12.90%) isolates. Studying some virulence factors of E. coli isolates revealed that 28 (90.30) isolates showed congored binding, 29 (93.50%) isolates were able to survive in serum and 23 (74.19%) were able to grow in calf serum, 25 (80.64 %) isolates could be proved as enterotoxin producers and caused accumulation of fluids in the intestinal tract of the inoculated mice. In addition, 28 (90.30 %) were able to produce verotoxins. The present study demonstrated the correlation between the presence of different virulence factors in E. coli isolates and its pathogenicity to newborn calves and its role in diarrheic calves