First detection and molecular characterization of rabbit hemorrhagic disease virus (RHDV) in Algeria.

Since the first detection of rabbit hemorrhagic disease (RHD), the rabbit hemorrhagic disease virus (RHDV) has been responsible for high morbidity and mortality worldwide, both in domestic and in wild rabbits. Despite the apparent control of RHD in rabbitries through vaccination, several studies highlighted the rapid evolution of RHDV by recombination, which may facilitate the emergence of new pathogenic strains. The aim of this study was to confirm the presence and characterize RHDV in Algeria. For this, rabbit samples were collected in the north of Algeria, between 2018 and 2021, from small farms where the virus was suspected after the sudden death of a high number of rabbits, and from healthy hunted wild rabbits. The domestic rabbits revealed clinical signs and lesions that were suggestive of RHD. RT-PCR showed that 79.31% of the domestic rabbit samples were positive for RHDV, while in 20.69%, including the hunted rabbits, the virus was not detected. Phylogenetic analysis of the Algerian strains allowed the confirmation and identification as GI.2 (RHDV2), and showed a close relation to GI.3P-GI.2 recombinant strains, suggesting a potential introduction from other countries, with an older strain potentially originated from neighboring Tunisia, while more recent isolates grouped with strains from North America. Our study reports for the first time the presence of GI.2 (RHDV2) in Algeria with multiple routes of introduction. Consequently, we propose that RHDV control in Algeria should be based on epidemiological surveys in association with an adequate prophylactic program.

Productive performance, metabolic, and hematologic parameters of pregnant nulliparous rabbit does according to dietary protein level.

OBJECTIVE: This study aims at investigating the productive performance, metabolic, and hematological profiles of Algerian local rabbits does during their first pregnancy and according to dietary protein content. MATERIALS AND METHODS: A total of 52 nulliparous rabbit does, 3,116 ± 72.9 g live weight, were allocated individually to three groups (17/18 females per group) being on isoenergetic diets [2,600 kcal Digestible Energy (DE)/kg] that differ in their digestible protein content by 15%, 17%, and 19%, respectively, for L, M, and H diets. All these diets were provided ad libitum. RESULTS: The use of a high protein diet did not affect does weight and feed intake during the pregnancy period. Statistically, no significant difference (p > 0.05) was recorded in born or alive litter size and birth weight. There was no effect of diet and sampling time (p > 0.05) on plasma metabolites but there were significant effects of sampling time (p < 0.0001) on the metabolic parameters studied with prolificacy used as a covariate. Hematologic indices in pregnant rabbits were not affected by the diet exceeded the red blood cells rate that increased significantly (p < 0.05) with the increase in dietary protein content during the different periods of gestation. CONCLUSION: The use of a high protein diet has no effect on weight during the pregnancy period. No effect of diet and sampling time on plasma metabolites and hematological profiles are recorded; however, significant effects of sampling time are recorded on the metabolic parameters.

Growth performances, carcass traits, meat quality, and blood metabolic parameters in rabbits of local Algerian population and synthetic line.

AIM: The objective of this work was to study the growth performance, slaughter traits, meat quality, and metabolic profile in rabbits of local Algerian population and a synthetic line. MATERIALS AND METHODS: In total, 120 weaned rabbits were used (60 per group). Growth traits were recorded from weaning (35 days) to slaughter (91 days). At slaughter, carcass traits, meat quality, and metabolic profiles were measured. RESULTS: The synthetic line showed heavier total weight and faster daily weight gain than the local population (+15% and +19%, respectively), better feed conversion (3.92 vs. 4.81 g/g), and heavier weight of cold carcass, and perirenal fat (+15%). No differences were found between the two groups in dressing out percentage, muscular pH, weight of liver, or scapular fat. Wider intestinal villi were found in the synthetic line (+20%, p<0.0001) allowing better absorption surface in this line. The synthetic line also showed higher fat content (3.41% vs . 2.22%, p<0.0001) in the meat and lower protein content (22.02% vs . 18.98%, p=0.0002). Glucose level was 19% higher in the local population than in the synthetic line. CONCLUSION: The synthetic line is well adapted to the local conditions of Algeria. This line has shown better growth, daily gain, and feed conversion, due to its better intestinal absorption surface.

Prevalence of coccidian infection in rabbit farms in North Algeria.

AIM: The aim of the present study was to determine the prevalence and intensity of rabbit coccidiosis (Oryctolagus cuniculus) in North Algeria. MATERIALS AND METHODS: During the study, 40 rabbit farms were investigated. The farms are located in the provinces of Tizi Ouzou, Médéa, and Djelfa which distributed, respectively, into three regions: East Tell Atlas Mountains, Central Tell Atlas Mountains, and High Plateaus. The number of oocyst per gram of feces (OPG) was determined by McMaster technique, and the Eimeria species were identified using morphological criteria. RESULTS: In the farms investigated, the prevalence of coccidian infection was estimated to 90% (80.7-99.3%) in rabbits after weaning. The classification of the farms according to their parasite load allowed us to show that 37.5% of the prospective farms have an oocyst excretion between 104 and 5×104 oocysts per gram and 22.5% excrete >5×104 oocysts per gram. Excretion levels by region show that the region of East Tel Atlas Mountains ranks first with 79% of farms with a parasitic load >104 coccidians compared to the regions of Central Tel Atlas Mountains and High Plateaus. In total, eight species of Eimeria were identified from oocyst-positive samples. Mixed infections with four Eimeria species were common. E. magna is the dominant species in comparison with E. media and E. irresidua with respective frequencies of 42.5% and 17.6% and 14.9% (p<0.001). Our results showed that the farms using anticoccidial drugs for their rabbits were low (25%) and the percentage of farms with poor hygienic conditions was 65%. There was a significant association between increased oocysts excretion and control measures of coccidian infection. CONCLUSION: The study revealed an overall prevalence of 90% in the three Algerian regions. A strong association was observed between Eimeria infection and hygienic status and preventional chemotherapy.