Role of livestock practices in the degradation of steppe spaces in Naâma area (south-western Algeria)

Steppe spaces of the Naâma area are rather well representative of all steppe spaces of western Algeria. They are exploited as rangelands with a mean carrying capacity of 10 sheep / hectare although the possibilities are only of 0.9 ha / sheep. Traditional livestock systems as currently practiced overexploit and degrade all kinds of vegetation along the year. They constitute the main threat on the sustainability of plant formations. The impact of the even archaic practices of livestock occurring in Naâma area, as in all the steppe spaces of Algeria, result in a yearly average regression of the density of 278 tufts / hectare. Concerning the total green biomass, we observe a mean annual reduction of 183 kg / ha. This impact is important and represents a serious short-term threat to the everlastingness of the steppe with Stipa tenacissima if no protective and rehabilitation measures are quickly undertakenLes formations végétales steppiques dans la région de Naâma, assez représentatives du sud-ouest oranais, sont soumises en permanence à un parcours ovin avec une charge pastorale moyenne de 10 ovins / hectare alors que les possibilités ne sont que de 0,9 ha / ovin. Cette surexploitation se traduit par une dégradation de la végétation et constitue la principale menace sur la pérennité des formations végétales. L'impact des pratiques d'élevage ne prenant pas en considération les possibilités de régénération des espèces palatables dans la zone de Naâma, comme dans tout l'espace steppique se traduit par une régression moyenne annuelle de la densité de l'alfa et du sparte de 278 touffes par hectare. Pour ce qui est de la biomasse verte totale, elle connaît une diminution moyenne annuelle de 183 kg par hectare. Cet impact est important et menace à court terme la pérennité des formations steppiques si aucune mesure de protection et de réhabilitation n'est entreprise rapidement

Insects as an alternative protein source for poultry nutrition: a review

This review summarizes the most relevant scientific literature related to the use of insects as alternative protein sources in poultry diets. The black soldier fly, the housefly, the beetle, mealworms, silkworms, earthworms, crickets, and grasshoppers are in the spotlight because they have been identified as an important future source of sustainable animal proteins for poultry feeding. Insect meals meet poultry requirements in terms of nutritional value, essential amino acid composition, nutrient digestibility, and feed acceptance. Furthermore, they are enriched with antimicrobial peptides and bioactive molecules that can improve global health. Results from poultry studies suggest equivalent or enhanced growth performances and quality of end-products as compared to fish meal and soybean meal. To outline this body of knowledge, this article states established threads of research about the nutrient profiles and the digestibility of insect meals, their subsequent effects on the growth and laying performances of poultry as well as the quality of meat, carcass, and eggs. To fully exploit insect-derived products, the effects of insect bioactive molecules (antimicrobial peptides, fatty acids, and polysaccharides) were addressed. Furthermore, as edible insects are likely to take a meaningful position in the feed and food chain, the safety of their derived products needs to be ensured. Some insights into the current knowledge on the prevalence of pathogens and contaminants in edible insects were highlighted. Finally, the effect of insect farming and processing treatment on the nutritive value of insect larvae was discussed. Our overview reveals that using insects can potentially solve problems related to reliance on other food sources, without altering the growth performances and the quality of meat and eggs

Rôle des types d’élevage dans la dégradation des formations steppiques dans la région de Naâma (Algérie sud-occidentale)

Role of livestock practices in the degradation of steppe spaces in Naâma area (south-western Algeria). Steppe spaces of the Naâma area are rather well representative of all steppe spaces of western Algeria. They are exploited as rangelands with a mean carrying capacity of 10 sheep/hectare although the possibilities are only of 0.9 ha/sheep. Traditional livestock systems as currently practiced overexploit and degrade all kinds of vegetation along the year. They constitute the main threat on the sustainability of plant formations. The impact of the even archaic practices of livestock occurring in Naâma area, as in all the steppe spaces of Algeria, result in a yearly average regression of the density of 278 tufts/hectare. Concerning the total green biomass, we observe a mean annual reduction of 183 kg/ha. This impact is important and represents a serious short-term threat to the everlastingness of the steppe with Stipa tenacissima if no protective and rehabilitation measures are quickly undertaken.Les formations végétales steppiques dans la région de Naâma, assez représentatives du sud-ouest oranais, sont soumises en permanence à un parcours ovin avec une charge pastorale moyenne de 10 ovins/hectare alors que les possibilités ne sont que de 0,9 ha/ovin. Cette surexploitation se traduit par une dégradation de la végétation et constitue la principale menace sur la pérennité des formations végétales. L’impact des pratiques d’élevage ne prenant pas en considération les possibilités de régénération des espèces palatables dans la zone de Naâma, comme dans tout l’espace steppique se traduit par une régression moyenne annuelle de la densité de l’alfa et du sparte de 278 touffes par hectare. Pour ce qui est de la biomasse verte totale, elle connaît une diminution moyenne annuelle de 183 kg par hectare. Cet impact est important et menace à court terme la pérennité des formations steppiques si aucune mesure de protection et de réhabilitation n’est entreprise rapidement.Yerou Houari, Benabdeli Kheloufi. Rôle des types d’élevage dans la dégradation des formations steppiques dans la région de Naâma (Algérie sud-occidentale). In: Revue d'Écologie (La Terre et La Vie), tome 68, n°2, 2013. pp. 157-165