DRY COW ANTIMICROBIALS USE TO CONTROL MASTITIS IN NORTHERN ALGERIA

The control of mastitis is a crucial step in the preparation of the next lactation in dairy cows. In order to assess the practices and attitudes surrounding the use of antimicrobials at dry-off, a survey was conducted among veterinary practitioners in fifteen provinces of Northern Algeria. The results revealed that 45.95% of the farms followed by the respondents were rather small in size comprising about ten cows per farm and that a large majority of the farmers practised gradual drying off (72.97%) without adjusting the feed ration (70.27%) to this stage. Antibiotic dry cow therapy (DCT) was a common practice and selectively performed in 86.49% of cases regardless of udder health status. Cefalexin was the most infused intra-mammary (IMM) antibiotic (40.54%), while tylosin was the one favoured for parenteral administration (48.15%). Analysis of factors influencing the antibiotic DCT efficacy showed that a frequent (13.51%) occurrence of new intramammary infections (IMIs) was related to farmers’ attitudes (self-medication) and the policy of blanket DCT. Although the use of a teat sealant was uncommon (71.43%) in the farming traditions, the substitution of antibiotics seems to be a plausible prospect, since the majority of participants (89.19%) agreed with the implementation of aromatherapy concept at dry-off, mainly as a complement to antibiotics. This survey gives an overview of risk practices regarding mastitis management in northern Algeria. Hence, further zootechnical, veterinary and organizational efforts need to be made to promote animal production and welfare as well as public health through improved udder health.

Tree-ring reconstruction of March-June precipitation from the Atlas cedar forest of Mount Takoucht, Béjaïa (northern Algeria)

Aim of study: A March-June precipitation has been reconstructed for the period 1830-2015 using Atlas cedar (Cedrus atlantica Manetti) tree-ring records. Area of study: Atlas cedar forest of Mount Takoucht (Béjaïa, northern Algeria). Material and methods: Seasonal correlations were computed in order to identify the best period of the year for the climate reconstruction. The temporal stability of the tree-ring signal for precipitation was checked using the split-sample calibration-verification procedure. The reconstruction was performed using the transfer function method. Main results: The reconstructed data revealed high interannual to decadal variation in late winter to early summer precipitation. Wet conditions dominated during the 1830s and 1840s and were followed by sustained dry conditions during the mid-19th century, which registered two of the most severe droughts (1858 and 1869) over the period of reconstruction. Relatively moderate climate conditions marked the late 19th and early 20th centuries. A gradual return towards drier conditions was observed from the 1920s and reached high frequencies of drought around mid-20th century. After an exceptional prolonged wet period of 24 years (1966-1989), the reconstruction registered its highest frequency in extreme dry/wet events: the decade 1993-2002 recorded the highest drought frequency of the reconstruction, with the third most severe dry event (1999), while the last years were marked by a clear shift toward wet conditions. Research highlights: These findings provide relevant records on past climate variability in one of the rainiest areas in Algeria and constitute valuable knowledge for specific drought and wet periods monitoring in the region.

Diversity of terrestrial gastropods in Kabylia region (Tizi-Ouzou, Northern Algeria)

The goal of this study was to record the malacofauna of the Kabylia region, Tizi-Ouzou, in Northern Algeria, at the edge of the Mediterranean Sea, and to report the distribution pattern of terrestrial gastropod diversity in five different types of habitat (dune, agricultural fields, rural sites, forests, and mountain locations). A total of 33 species of terrestrial snails and slugs were recorded, which represented 27 genera of 19 families, mainly Geomitridae and Helicidae. The rural habitat was the richest, with 23 species, while the mountain habitat yielded 20 species. The dune and forest habitats showed the smallest species richness.

IMPACT OF NATURAL ENEMIES ON LARVAE OF THAUMETOPOEA BONJEANI (LEPIDOPTERA NOTODONTIDAE) IN ASSOCIATION WITH THAUMETOPOEA PITYOCAMPA IN NORTHERN ALGERIA

The cedar processionary moth, Thaumetopoea bonjeani (Lepidoptera: Notodontidae), is a serious pest of the Atlas cedar Cedrus atlantica in north-western Africa and it is involved in the decline of this endangered tree species. Natural enemies of the cedar processionary moth are poorly known, especially for parasitoids, predators and pathogens of the larval-pupal life stages. Mature larvae were collected and examined in 2014 and 2015 in natural stands of Atlas cedar in the Djurdjura (northern Algeria), in occurrence with pine processionary moth Thaumetopoea pityocampa. The overall mortality rate of larvae of Thaumetopoea bonjeani ranged from 26.4% to 31.1%, with generalist predators and parasitoids being more effective than pathogens. Four primary parasitoid species were recorded, of which four tachinid flies and one braconid wasp, as well as four predatory beetles and one fungus. The most important species were the carabid Calosoma sycophanta and the tachinid Compsilura concinnata. The cooccurrence of T. bonjeani and T. pityocampa may offer to generalist natural enemies an extended period of availa- bility of similar preys, as the two processionary moths have different life cycles. The sharing of natural enemies between the two species of Thaumetopoea can mitigate the outbreaks of both species.