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This paper examines the relationship between karst landforms and biological diversity. We investigated the distribution of a migratory threatened species, the Sooty Falcon (Falco concolor), within different karst landform zones identified in the White Desert National Park in the Farafra Oasis, Western Desert, Egypt. Field surveys of the distribution and breeding of Sooty Falcons were conducted within different karst landforms in the White Desert National Park during September to November from 2009 to 2013. Numbers of Sooty Falcon pairs recorded in the park have ranged from 33 to 101 per annum and the species has been recorded in all years from 2009 to 2013. The number of single adults and juveniles ranges from 11 to 71, while the nestlings recorded range between 29 and 88 through the study period. Our results confirm that the distribution pattern, density and breeding success of the falcons are strongly related to solution cavities formed within tower karsts which are the home base for the species. The increased numbers in the last two years are likely related to lesser impacts of human disturbance as a result of a decrease in tourist activity in the study area due to security concerns.

Fish with bacterial septicemic syndrome (BSS) exhibit very similar clinical signs regardless of the etiological agents. Members of Aeromonas, Pseudomonas, Vibrio, Edwardsiella, Streptococcus and Lactococcus species are considered the most reported bacterial pathogens incriminated in such syndrome. Aeromonas hydrophila, Edwardsiella tarda and Streptococcus iniae are 3 major pathogens share in the BSS associated losses in aquaculture and considered problematic for growth of tilapia and catfish production in Egypt. Therefore, rapid and accurate diagnosis is highly needed for controlling their disease outbreaks, particularly, in mixed infections. In an attempt to elucidate the main causative pathogen, a novel multiplex PCR (m-PCR) was newly designed in this study. The developed m-PCR involves amplifying the three multiple genes in single reaction based upon primers deduced from the regions carrying 16S rRNA, etfA and 16S RNA genes of A. hydrophila (Aeromonas spp.), E. tarda and S. iniae, respectively. Prior to perform m-PCR, individual PCR assays were carried out to adapt suitable laboratory and m-PCR assays conditions. The specificity of the developed m-PCR was confirmed by the fact that only specific fragments were amplified equivalent for 953, 415 and 300 bp corresponding to A.hydrophila, E. tarda and S. iniae, respectively, and that was evident with both extracted DNAs and the bacterial cells. More specifically, these specific bands were obtained also when either the extracted DNAs or the bacterial cells of the three pathogens mixed together in the reaction. The developed m-PCR is accurate, sensitive, fast and simple technique for the simultaneous detection of A. hydrophila (Aeromonas spp.), E.tarda, and S. iniae, three major bacterial pathogens involved in BSS incidence in Egypt.

A study was conducted to investigate the pathogenicity and the median lethal dose (LD50) of Aeromonas hydrophila isolated from clinically diseased catfish against apparently healthy homologous fish to evaluate the lethality of extra-cellular products (ECPs) of the isolated strain in vivo. For pathogenicity experiment, five different concentrations of Aeromonas hydrophila strain BNS 01614 including 3× 108, 1.5 × 108, 1.5 × 107, 1.5 × 106 and 1.5 × 105 CFU/fish used via intra peritoneal. The results revealed that pathogenicity of BNS 01614 was confirmed by the mortality of 30 % to 100 % of all tested fish within 4 to 12 days with LD50 1.5 × 107 CFU/fish. The Concentrated extracellular products (ECPs) of the selected bacterium were prepared and confirmed to be toxic in Clarias garipineus with LC50 of 20µg.

Dromedary camels can survive and reproduce in desert areas. The unique anatomical structure of the kidney enables the camel to prevent water loss. The present study aimed to investigate the ultrastructure of the peroxisomes in the normal kidney of the adult dromedary camel. Tissue samples were taken from the cortex and outer medulla of the kidney of eight camels. The samples were then processed for histological and ultrastructural investigations. The epithelial cells of the proximal tubules displayed peroxisomes with varying sizes and shapes. The peroxisomes were observed in either dispersed or clustered arrangement. Each peroxisome exhibited a homogenous matrix enveloped by a single membrane. Several peroxisomes exhibited one or more dark marginal plates that were always strongly associated with the smooth endoplasmic reticulum. The intensity of the peroxisomal matrix differed significantly, either within the same cell or across different cells. The intensity was light or dark, with a few peroxisomes presenting a similar intensity to that of the mitochondria. Some peroxisomes contained nucleoids within their matrix. The peroxisomes in the first and second sections of proximal convoluted tubules were scattered and primarily located in the region between the microvilli and the underlying mitochondria. The peroxisomes in the third region were abundant and frequently aggregated in clusters throughout the cytoplasm. In the fourth region, the number of peroxisomes was low. The proximal straight tubule had a limited quantity of peroxisomes. In conclusion, peroxisomes in the proximal tubule in kidney of normal dromedary camel were similar in shape and size to other mammals; however, heterogeneity exists as a result of differences in species‐specific peroxisomal proteins. Peroxisomes are suggested to be a major source of metabolic energy and act as hydrogen peroxide (H2O2) scavengers, resulting in the release of water and oxygen. [ABSTRACT FROM AUTHOR]

The present study was conducted to investigate the internal and external biosecurity levels and their association with Mycoplasma gallisepticum infection in broiler farms in Khartoum State, Sudan. Sixty-six broiler farms were selected. A questionnaire of 77 questions on internal and external biosecurity measures was administered during each farm visit. A total of 360 blood samples were collected and used for serological examination to detect antibodies against M. gallisepticum. The overall score of biosecurity was 0.57, and the average score of internal biosecurity (0.75) was higher (p<0.01) than the average score of external biosecurity (0.51). Poor internal biosecurity practices were observed in 23.4% of broiler farms, whereas most farms (93.6%) recorded poor external biosecurity. A significant (p<0.01) positive correlation was encountered between the external biosecurity and the number of houses (0.62), as well as the number of workers (rs= 0.54). Both internal and external biosecurity displayed significant positive correlations with the number of birds (rs= 0.64, 0.35; p< 0.05). Fifty percent of the farms were positive for M. gallisepticum. The disease incidence correlated positively with the spread of manure on neighboring farms (rs= 0.44, p<0.05). A negative correlation was observed between the presence of Mycoplasma and the distance between farms (rs= -0.50, p<0.01) as well as farm enclosure (rs= -0.44, p<0.05). It is concluded that broiler farms in Khartoum State exhibited low biosecurity measures and a high seroprevalence of M. gallisepticum infection. Further efforts are necessary to improve external biosecurity practices. [ABSTRACT FROM AUTHOR]

Lectins are carbohydrate‐binding proteins that are highly selective for sugar groups on other molecules. Siglec5 is a cell‐surface lectin that belongs to the sialic acid‐binding Ig‐like lectins (Siglecs) and acts as a suppressor of immune responses. In this study, immunohistochemistry, western blotting and quantitative real‐time polymerase chain reaction (qRT‐PCR) were used to detect the expression of Siglec5 in the male reproductive tract of dromedary camels during the rutting season. Siglec5 displayed strong immunostaining in the cranial and caudal testicular regions and moderate immunostaining in the rete testis. Different parts of the epididymis showed varying immunoreactions to Siglec5. The spermatozoa in the testes and epididymis also showed positive immunostaining for Siglec5, whereas, the vas deferens showed negative immunostaining for the protein. The results obtained by western blotting confirmed the immunohistochemical detection of the protein in the testicular and epididymal tissues. The results of qRT‐PCR showed that Siglec mRNA was expressed differently in each part of the testis and epididymis; the highest levels of expression were observed in the caudal part of the testis and in the head of the epididymis. In conclusion, the present study revealed that Siglec5 is mainly located in the testis and epididymis, where sperm production and maturation occur. Therefore, this protein may play an essential role in the development, maturation and protection of camel sperm. [ABSTRACT FROM AUTHOR]