Algeria represents a reservoir of genetic diversity with local sheep breeds adapted to a large range of environments and showing specific features necessary to deal with harsh conditions. This remarkable diversity results from the traditional management of dryland by pastoralists over centuries. Most of these breeds are poorly productive, and the economic pressure leads farmers to realize anarchic cross-breeding (that is, not carried out in the framework of selection plans) with the hope to increase animal's conformation. In this study, eight of the nine local Algerian sheep breeds (D'men, Hamra, Ouled-Djellal, Rembi, Sidaoun, Tazegzawt, Berber and Barbarine) were investigated for the first time by genome-wide single-nucleotide polymorphism genotyping. At an international scale, Algerian sheep occupied an original position shaped by relations with African and European (particularly Italian) breeds. The strong genetic proximity with Caribbean and Brazilian breeds confirmed that the genetic make-up of these American breeds was largely influenced by the Atlantic slave trade. At a national scale, an alarming genetic dilution of the Berber (a primitive breed) and the Rembi was observed, as a consequence of uncontrolled mating practices with Ouled-Djellal. A similar, though less pronounced, phenomenon was also detected for the Barbarine, another ancestral breed. Genetic originality appeared to be better preserved in Tazegzawt, Hamra, D'men and Sidaoun. These breeds should be given high priority in the establishment of conservation plans to halt their progressive loss. For Berber and Barbarine that also occur in the bordering neighbor countries, urgent concerted transnational actions are needed.

Exposition of variations between breeds is very important for genetic diversity. Determination of this variation is needed to reveal population structure and relationship between populations and planning national breeding and conservation programmes. This study was carried out in 296 animals from 12 different local sheep breeds (Barbarine, Ouled Djellal, Ifilene, Srandi, Darâa, Rembi, Berbere, Taâdmit, Hamra, Sidaou, Tazegzawt and D'men) reared in different regions of Algeria. Fifteen microsatellite markers were used to determine between breed genetic diversity. The population of 12 sheep breeds studied from Algeria exhibited a high number of alleles (24.67) and polymorphic information content (0.90). Observed heterozygosity values were lower than expected for all molecular markers except INRA0123 locus. Obtained G ST value from the present study indicated that 1.9% of total genetic variation resulted from the differences between the breeds. The present study supplied important information to understand between breed genetic differences. Moreover, it has provided the opportunity to discuss with previously reported results. In light of these findings, it can be said that studied microsatellite markers can be successfully used to determine genetic diversity and population structure in Algerian sheep breeds. ARTICLE HISTORY

This experiment was carried out on Ouled Djellal rams in order to study the effect of season on testicular size, serum testosterone level and semen characteristics for a period of one year. Blood samples were obtained via jugular vein, and semen was collected by using an electro-ejaculator from six fertile male rams (2-4 years of age) on a monthly basis. In this breed, testis parameters varied seasonally showing the highest average values during autumn. However, the variation of body weight, GSI, serum testosterone levels, mass motility, individual motility and sperm concentration were not significant during the sampling period. The results reported show that the lowest and highest levels of semen volume were recorded in winter (0.62±0.11 ml) and in autumn (1.23±0.09 ml) respectively. The pH value and total number in sperm showed a uniform pattern with low scores during breeding season and high scores in non-breeding season. High percentage of live sperm was recorded during the summer, and high percentage of abnormal sperm was recorded during winter.

There is no doubt that the well-being of cattle, as for other beef species, is a consumer concern. The pre-slaughter period includes a series of potentially stressful interventions to which animals are subject can significantly affect the quality of meat. This is closely related to the disturbances of the physiological state of the animal and its possible reactions to stress. The present study was involved in 38 beef cattle of different ages (<2 years n=19 and >2 years n=19), sexes (male n=20 and female n=18), and breeds (Prim'Holstein n=19, autochthone cattle n=19).The evaluation of stress response of cattle was carried out during their landing in slaughterhouse, before and at the time of slaughter by exploration do some blood biochemical indices (cortisol, testosterone and ACTH) and urinary parameters (cortisol, catecholamines and glucose). The results showed significant breed effect on cortisolemia with a high levels in autochthone cattle compared to Prim'Holstein particularly 20mn before the slaughter (26.8 ng / ml vs 8.6 ng / ml, p <0.05). Similarly, females had high but no significant cortisolemia compared to males before and at bloodletting(21.75 ng / ml vs 18.67 ng / ml at 12h ante mortem, 18.75 ng/ml vs 17 ng/ml at 20 mn before slaughter and 29.25 ng / ml vs. 21.33 ng / ml at bloodletting, P>0.05). Older animals were more reactive to slaughter stress at 20 mn ante mortem and bloodletting (Cortisolemia:21 ng/ml and 29.8 ng/ml) than young, ones who showed more cortisolemia 12h ante mortem (21.2 ng / ml) and also significant difference of testosterone levels (p <0.01) .The urinary parameters did not showed any significant changes during the slaughter preparation stages and bleeding (P>0.05) and they were not significantly influenced by animals characteristics (age, breed and sexe; P>0.05).

The objective of this study was to predict the body weight of 66 females and 15 males Ouled Djellal breed aged over 2 years using fourteen simple linear body measurements and CREVAT formula. The total body length (TBDL), body length (BDL), scapular-ischial length (SIL), withers height (WH), heart girth (HG), chest depth (CD), paunch girth (PG), shoulder width (SW), hip-width (HW), trochanter width (TW), ischia width (IW), pelvis length (PL), cannon length (CL) and cannon perimeter (CP) were measured in centimeters, and body weight (BW) was determined in kilogram using a weighing scale. Results of the correlation coefficient showed that heart girth and the withers height were highly correlated with body weight (r = 0.93 and r =0.91 respectively), with variations by sex. Results of the stepwise regression showed that heart girth (HG), withers height (WH), scapular-ischiallength (SIL) and thecannon perimeter (CP) are the best prediction parameters of body weight in animals studied. From the CREVAT formula, the body weight was estimated by the HG (in meters): BW = 57.9 HG3. According to the different statistical methods used and the formula of CREVAT, we can conclude that body weight in Ouled Djellal breed can be estimated using simple linear body measurement of heart girth.