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Antimicrobial and anti-Varroa destructor L. activity of the essential oil (EO) of clove (Syzygium aromaticum L. Myrtaceae) was evaluated in this study. Antimicrobial activity concerned 9 bacterial strains (Bacillus cereus, Escherichia coli ATCC 25911, Staphylococcus aureus 29213 ATCC, Proteus mirabilis, Serratia marcescens, Enterobacter sakazakii, Pseudomonas aeruginosa ATCC, Escherichia coli and Acinetobacter sp.), a fungal strain (Penicillium sp.) and a yeast species (Candida albicans). The extraction of the EO was carried out by the method of hydrodistillation. Results showed that EO has no toxicity on bees Apis mellifera. EO demonstrated effective and stable anti-V. destructor activity, indicating the absence of possible resistance, in contrast to what was observed for Amitraz. The inhibitory activity of EO revealed an inhibition zone of diameter varying between 20 mm and 42 mm for bacteria. However, no inhibition zones were observed for Pseudomonas aeruginosa ATCC. The inhibitory activity of EO on Penicillium sp and Candida albicans revealed an inhibition zone of 39 mm in diameter. This study shows that the EO of cloves constitutes a simple and natural treatment, without inconveniences, with a high activity antimicrobial and anti-Varroa destructor which merits it to be proposed as a means to fight against varroosis and the tested pathogens. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop statistical models to predict body weight from goat's body measurements. Data on 1702 goats for circumferences of chest (CG), abdominal circumference (AC) and spiral circumference (SC), height at withers (WH), body length (BL), and body weight (BW) were analysed to study the relationship between linear body measurements and body weight. The present study revealed that in the goats from all breeds studied (Arabia, Makatia, Kabyle, M'zabite, Saanen and Alpine), the weight evolved in the same direction and at the same rate as the linear measurements chosen. The linear measurements were all significantly correlated with animal weight (p<0.001). Results indicated that Arabia goats had the highest WH (71.07 cm) and CG (17.72 cm). The highest measurements were reported in Alpine goats for AC (97.73 cm), BL (78.05 cm), SC (106.29 cm) and BW (41.60 kg). The Kabyle breed were recorded with the lowest values for the WH (64.95 cm), BL (67.58 cm) and BW (29.52 kg). The average live weight was 38.15±10.90 kg with differences according to age, sex and breed (Arabia, Makatia, Kabyle and M'Zabite). Positive and highly significant (p<0.001) correlations were observed between BW and the majority of independent variables. The highest relationship was illustrated between CG with BW (r=0.922). Linear regression analyses were performed to develop the models. The simple regression analysis found all parameters to be significant (p<0.001) (WH, BL, CG, AC and CS) and CG gave more precision on the weight when using a single measurement parameter (R2 varied between 0.950 and 0.967). Therefore, the following formula can be used to estimate the live weight of the animals using only the chest circumference (P=75*CG). The development of these equations would enable producers and researchers to predict the animal body weight and develop strategic plans for the relevant goat herds. [ABSTRACT FROM AUTHOR]

This study aims to investigate, for the first time in Algeria, the effect of seasonal climatic changes on the hematological profile of Holstein dairy cows as an indicator for their physiological status assessment. The study was conducted between November 2018 and October 2019 and was performed on a lot of 14 dairy cows. Blood samples were collected quarterly during this study period. The data regarding seasonal changes in hematological parameters were not significant concerning red blood cell count (RBC), hemoglobin concentration (Hb) and mean corpuscular volume (MCV). However, variations were significant for hematocrit (HCT), mean corpuscular hemoglobin content (MCH), mean corpuscular hemoglobin concentration (MCHC) and blood platelets (PLT). The percentage of HCT was higher in autumn (27.99%) and spring (28.58%) compared to winter (26.52%) and summer (26.75%), (p<0.05). MCH, MCHC and PLT levels were higher in summer compared to the other seasons (p<0.05), (p<0.01) and (p<0.001), respectively. The highest number of WBC was generally observed in summer and autumn and the lowest in winter and spring (p<0.01). The ratio neutrophils/lymphocytes (N:L) was equal to 1.01, 0.79, 0.98 and 0.89 in autumn, winter, spring and summer, respectively of which this difference was not significant. This study might be helpful for providing base line information on the hematological profile of dairy cattle for the evaluation of physiological status. [ABSTRACT FROM AUTHOR]

In goat production, the reproductive efficiency of bucks must be taken into account. Testicle size is the most appropriate parameter to directly improve the reproductive performance of females. In this study, body weight (BW), body condition score (BCS) and testicular and epididymal parameters of Arabia goats were studied. A total number of 200 bucks were randomly selected and classified into three age categories (6-12 months, 13-24 months and >2 years). BW, BCS, mean scrotal circumference, testicular volume, testicular diameter, testicular length, testicular weight, testicular density, epididymal weight, epididymal length, epididymal tail length, caput weight, corpus weight, caudal weight, Gonadosomatic Index, Epididymosomatic index and Epididymal-Testicular weight ratio were measured. A highly significant correlation was found between all parameters (p<0.05). The values of all parameters increased significantly with age, with the exception of the gonadosomatic and epididymosomatic indices, which decreased with age (p<0.05). These results provide data that can be used to anticipate an adequate ante-mortem sperm reserve based on testicular size in the preliminary selection of breeding males from the local sexually mature population. [ABSTRACT FROM AUTHOR]

Subclinical mastitis (SCM) is the most common form of mastitis and the greatest cause for concern in dairy cows. The overuse of antibiotics for the treatment of mastitis leads to the development of resistance, resulting in the use of symbiotics. The study was carried out between February and May 2017 at a pilot dairy cattle farm in the Tipaza region (north-central Algeria) aiming to investigate the effect of a symbiotic on SCM. California Mastitis test (CMT) was used to diagnose SCM in a total of 240 dairy cows. A number of 58/240 (24.16%) cows were found to have SCM. These mastitis cows were then divided into two lots; an experimental lot of 37 cows and a control lot of 21 cows. A symbiotic was administered to the experimental lot once a month for three months. Cell count, microbiological analysis and analysis of certain physicochemical parameters of the milk were applied before and after each administration of the symbiotic. The results revealed that the average somatic cells count (SCC) in cows from the control lot was higher than that of cows from the experimental lot throughout the study period (p<0.0001). Staphylococci were isolated from 51/58 (87.93%) of the mastitis cows, of which 21 (36.20%) were infected with Staphylococcus aureus and 30 (51.72%) with coagulase-negative Staphylococcus. Enterobacteriaceae were isolated from 36/58 (62.07%) of the mastitis cows, of which 21 (36.20%) were due to Escherichia coli strain and 15 (25.86%) to other strains of Enterobacteriaceae. After administration of the symbiotic, the prevalence of S. aureus and E. coli decreased significantly in the experimental lot compared to the control lot (p<0.001). The physicochemical characteristics of the milk were not altered by the administration of the symbiotic. All these results show that the symbiotic constitutes an adequate solution to replace antibiotics in the treatment of SCM. [ABSTRACT FROM AUTHOR]

In the reinforced concrete study, the concrete steel connection is a "key element» in the behavior of this composite because it will allow the transfer of forces between steel and concrete. The understanding of this phenomenon and its inclusion in the numerical analysis of reinforced concrete structures are the main objects of this research work; the approach suggested for modeling this problem is the extended finite element method (X FEM) that allows the introduction of the interface independently by the mesh. Steel and concrete bond has been studied through a pull-out test as recommended by RILEM. This work provides some ideas about the adhesion's behavior, thus an experimental campaign was carreid out, measuring the concrete's andsteel's constraints and sliding over concrete. The bond stress -slip curve shows a similar behavior between experimental and theoretical results. The obtained results show the improvement of the adhesion constraint according to the increase of concrete compressive strength. Indeed, the transmission of forces between reinforcement and concrete enclosing it gives rise to a relatively complex state of stress. This paper presents a stabilized formulation for 3D contact problems, in the framework of X-FEM. It is shown that the choice of a simple algorithm and the type of mesh (concrete - steel bond) is a good solution for the determination of the adhesion behavior. [ABSTRACT FROM AUTHOR]

The article discusses a study which assessed the natural infection in young dairy calves at several regions in northeastern Algeria using the description of the prevalence and intensity of oocyst excretion and diarrhea pattern. The modified Ziehl-Neelsen staining techniques were used to process and analyze the feces of dairy calves. Cryptosporidiosis is described as a zoonotic protozoan disease which affects a large range of vertebrate hosts. One risk factor for this disease is the age of the animals. The study revealed the frequent occurrence of Cryptosporidium sp. among the calves in the study.