Moufida Atigui

Isolation and characterisation of lactic acid bacteria strains from raw camel milk for potential use in the production of fermented Tunisian dairy products

The aim of this work was to study the suitability of camel milk for the production of dairy products by lactic acid fermentation. Sixty strains of lactic acid bacteria (LAB) were isolated from camel milk. The strains were tested for their acidification activity, ability to use citrate, exopolysaccharide production, lipolytic, proteolytic activities and resistance to antibiotics. Ten strains were investigated for their ability to metabolize carbohydrates and that resulted in the identification of 5 Lactococcus lactis, 1 Lactobacillus pentosus, 2 Lactobacillus plantarum, 1 Lactobacillus brevis and 1 Pediococcus pentosaceus strains. Two strains of Lactococcus lactis SCC133 and SLch14 were selected to produce traditional Tunisian fermented dairy products (Lben, Raib, Jben cheese and Smen). These strains were chosen based on their acid production capacity and their ability to produce a high yield of biomass.

Growth, feed intake and carcass characteristics of indigenous goats fed local resources in Tunisian arid land

Native genetic resource of goats is a pivotal source for meat and milk in southern Tunisia. Feeding is one of the most important activities of goat husbandry. Perceptions on the role of native feed resources for growth and carcass characteristics have not been well studied. Therefore, the present study was designed to help understand and to compare the influences of local forage resources (grass hay, dried olive leaves, Stipa tenacissima and oat hay) on growth performance and carcass characteristics of kids. The kids with the age of 4 months (average live bodyweight of 15 ± 58 kg) were selected for the study. The three study groups in the 90-day trial were as follows: Group C, where animals received oat hay only (control), Group OL, where animals received olive leaves (dried) + S. tenacissima and Group GH, where animals received grass hay. A daily allowance of commercially available concentrate (305 g DM/day) was offered to all groups (making about half of the total DM intake). At the end of the experiment, all animals were slaughtered. Statistical analysis showed that total DM intake was lower (P < 0.001) in C group (490.77 g) than the other two groups having similar DM intake (619.22 and 589.28 g for OL and GH, respectively). Average daily gain was comparable for the three groups (38.33, 40.71 g and 39.52, respectively, for C, OL and GH), with similar final liveweights. Cold carcass weight and carcass yield were not affected by diet treatment. Diet had no significant effect on individual organ weights and carcass composition. The use of the local forage resources evaluated in this trial could be used for the local goat population without loss of productivity when they make up about half of the diet along with a concentrate feed.