Seroprevalence of and associated risk factors for Leptospira interrogans serovar Hardjo infection of cattle in Setif, Algeria

Background: Leptospirosis is a cosmopolitan zoonosis caused by Leptospira interrogans responsible for heavy loss both economically and in health, in humans and animals. This study was conducted to determine the seroprevalence and risk factors associated with Leptospira interrogans serovar Hardjo infection in cattle in the state of Setif, northeastern Algeria.Methodology: Between the period 2015 and 2019, a total of 48 randomly selected herds of cattle were investigated, and 406 sera from apparently healthy cattle were analyzed using an indirect enzyme-linked immuno-sorbent assay (ELISA). In order to determine possible risk factors related to leptospirosis, a pre-validated questionnaire was administered to herd owners.Results: The herd prevalence of Leptospira interrogans serovar Hardjo was 31.25% (15/48, 95% CI 19.95–45.33) while the cattle prevalence was 5.42% (22/406, 95% CI 3.61–8.07). Multivariable logistic regression analysis showed that the age of cattle between 3 and 6 years (OR = 9.25; p< 0.03), breeding herd size > 20 cows (OR = 13.65; p< 0.01), and semi-intensive management system (OR = 0.21; p< 0,02) were significantly associated with seropositivity to Leptospira interrogans serovar Hardjo.Conclusion: We concluded from this study that Leptospira interrogans serovar Hardjo is circulating among cattle farms in the state of Setif, Algeria. Furthermore, we recommend more studies to be carried out to prove the infectivity and implementation good hygienic practices among cattle farms and people at risk. Keywords: ELISA, herds, questionnaire, leptospirosis, prevalence, Algeri

Salmonella Dublin associated with abortion in dairy cattle in Algiers and comparison of different diagnostic methods

Background: In cattle, many serotypes of Salmonella enterica are responsible for a wide variety of clinical manifestations, which can cause considerable economic loss. Some serotypes can cause cows to abort sporadically, such as the Dublin serotype. This study was carried out on different cattle farms in the Algiers region to determine the prevalence of Salmonella Dublin using bacteriological and immunological methods.Methodology: The prevalence of Salmonella was determined by bacteriological analysis in accordance with the reference method AFNOR NF U 47-100 on faecal samples collected from 184 cattle belonging to 19 different farms, and serotyping for S. Dublin. Immunological analysis by enzyme-linked immunosorbent assay (ELISA) for S. Dublin was carried out on milk samples collected from 91 cattle. A survey of case (n=5) and control (n=14) farms for comparative analysis was performed to demonstrate a link between abortion in cows and prevalence of S. Dublin with both bacteriological and immunological methods. Sensitivity, specificity, Cohen Kappa coefficient, McNemar test odds ratios, and confidence intervals were calculated using Winepiscope 2.0 and StatA 9.1 software,and p<0.05 was considered as statistically significant.Results: The bacteriological results showed a prevalence of 7.6% (95%CI: 3-10), for Salmonella and serotyping revealed a prevalence for S. Dublin of 2.7%. The immunological analysis of milk by the ELISA technique revealed a prevalence of 13.2% (95%CI: 5-20) for S. Dublin. The comparative study between immunological results from milk and bacteriological results from faeces for detecting S. Dublin  showed poor agreement between the two tests (k=0.25), with enzyme immunoassay being significantly more sensitive than the bacteriological test (p<0.05). The results of the survey did not demonstrate a clear association between bacteriological detection of S. Dublin in faeces and abortion in cows (OR=8.66, 95%CI: 0.58-130.12). However, with the immunological analysis of milk for S. Dublin, there was a significant positive association (OR=62.33, 95%CI: 2.13-18.22) between a positive antibody response to S. Dublin in milk and the presence of abortions on the farm.Conclusion: In view of these results, we can conclude that Salmonella infections should systematically feature in the differential diagnosis of abortions in dairy cattle in Algeria. Keywords: S. Dublin, cattle, faeces, milk, abortion, immunology, bacteriology, Algier

L'effet de l'extrait végétal de Yucca Schidigera sur l'excrétion oocystale chez le poulet de chair

In Algeria, coccidiosis constitutes one of the main constraints which hinder the development of the poultry production and is responsible for major losses to the poultry industry, reducing performance and increasing production costs, especially an increase of mortality and misuse of antibiotics. These molecules have fatal effects on the animal and public health, thus, alternatives were introduced, in particular the extracts of plants. The present study, conducted in October 2013, was carried out in five hundred broiler chicks (Hubbard F15 strain). The chicks were monitored from birth to the 52nd day. These animals, with homogeneous weight of 93 g and mixed sexes, came from the same hatchery and underwent the same environmental conditions. Animals of the first lot, identified as “Control lot” received a food exempt from any additive but antibiotics added to water. The animals of the second lot, identified as “Experimental lot”, received a water exempt from any additive and the same food added with the Yucca Schidigera extract. The objective of this study was the evaluation of the oocystale excretion by Mac Master’s method to estimate the activity of the Yucca Schidigera extract. The results highlighted an increase of oocystale excretion until 82.250 oocysts.g-1 of feces in the control lot and 22.950 oocysts.g-1 of feces in the experimental lot. The average levels of oocysts were significantly lower during three weeks from J14 to J35 in the experimental lot, then remained comparable for the rest of the experiment period (J36 to J51). These results showed that this additive considerably reduced the coccidian eggs elimination and proved its efficiency in the coccidiosis control. Keywords: Yucca Schidigera, Coccidiosis, Broilers, Antibiotics.En Algérie, la coccidiose constitue l’une des principales contraintes qui entrave le développement de la production avicole et cause d’énormes pertes économiques, en l’occurrence l’augmentation du taux de mortalité et l’usage abusif des antibiotiques. Ces derniers ont des effets néfastes sur la santé humaine et animale. Ainsi, des alternatives ont vu le jour, en particulier l’utilisation des extraits de plantes. La présente étude, mise en place en octobre 2013, a été menée dans un élevage comportant cinq cent poussins d’un jour appartenant à la souche de type chair Hubbard F15. Les poussins ont été suivis de leur naissance jusqu’au 52ème jour. Ces animaux, d’un poids homogène de 93 g et de sexes mélangés, provenaient du même couvoir et ont subi les mêmes conditions d’ambiance. Les animaux du premier lot, identifié comme «Lot témoin», recevaient un aliment exempt de tout additif mais une eau additionnée d’antibiotiques. Les animaux du deuxième lot, identifié comme «Lot expérimental», recevaient une eau de boisson exempte de tout additif et un même aliment additionné de l’extrait de Yucca Schidigera. L’objectif de cette étude a été l’évaluation de l’excrétion oocystale, par la méthode de Mac Master, pour déterminer l’activité de l’extrait de Yucca Schidigera. Les résultats ont révélé une augmentation d’excrétion oocystale jusqu’à 82.250 oocystes.g-1 de matières fécales pour le lot témoin et 22.950 oocystes.g-1 de matières fécales pour le lot expérimental. Les nombres moyens d’oocystes ont été significativement plus bas durant 3 semaines allant de J14 à J35 dans le lot expérimental, puis devenaient comparables le reste du temps de J36 à J51. Ces résultats montrent que cet additif a considérablement réduit l’élimination des œufs de coccidies et prouvé son efficacité dans la maîtrise de la coccidiose. Mots clés: Yucca Schidigera, Coccidiose, Poulet de chair, Antibiotiques.   &nbsp

Advanced Biometric Technologies: Emerging Scenarios and Research Trends

Biometric systems are the ensemble of devices, procedures, and algorithms for the automatic recognition of individuals by means of their physiological or behavioral characteristics. Although biometric systems are traditionally used in high-security applications, recent advancements are enabling the application of these systems in less-constrained conditions with non-ideal samples and with real-time performance. Consequently, biometric technologies are being increasingly used in a wide variety of emerging application scenarios, including public infrastructures, e-government, humanitarian services, and user-centric applications. This chapter introduces recent biometric technologies, reviews emerging scenarios for biometric recognition, and discusses research trends