Investigations were conducted to determine the influence of physiological stage and parity on some indicators of energy, nitrogen and mineral metabolisms in sheep Ouled Djellal living in the Algerian Southeast arid area. The study was carried out on 100 clinically healthy multiparous and primiparous ewes, aged 2 to 7 years. The animals were divided into three ewe groups: Pregnant (P), lactating (L), and empty (E). Biochemical analysis of blood samples concerned the determination of the values of 11 metabolites [glucose, cholesterol, triglycerides, urea, total protein, albumin, calcium (Ca), phosphates (PO 4 ), sodium (Na), potassium (K), and magnesium (Mg)]. The results showed that pregnant ewes and multiparous ones have the lowest blood glucose levels and the highest proteinemia. However, the lowest total protein and albumin values were found in empty sheep. Cholesterol and triglyceride levels were the highest in lactating and primiparous ewes. In this study, the most important calcium levels were recorded in lactating ewes which showed the lowest magnesium levels. The pregnant ewes had the highest sodium levels and low phosphatemia. Potassium levels were comparable in all animals. Statistical analysis showed that the physiological stage has a significant influence (p < 0.05) on serum glucose, triglycerides, phosphorus and potassium levels and a highly significant effect (p < 0.001) on urea, and magnesium levels. No parity effect has been observed in our study.

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Weather hazards and changing climatic regimes combined with socio-cultural changes are forcing farmers living in Algerian steppe territories to find new strategies to maintain their business, particularly in terms of animal feeding sources. Animal's nutritional needs in the past used to be met mainly by grazing lands which nowadays cover less than 40% of feeding sources. This study aimed to determine the status of livestock system practices used by breeders in Algerian steppe territories and presents a novel method in identifying intensive systems. Data were obtained from 90 farms through a survey in the province of Tebessa. The farms were divided by their characteristics with a discriminant analysis by zone to know the characteristics of each region. Moreover, a discriminant analysis was performed to select the variables that best differentiated the farms characterised by a different percentage of feed purchased (PFP), which was taken as an index of intensive management. A stepwise regression analysis was also conducted to get predictors variables that mainly influence the percentage of feed purchased and characterise the intensive livestock farms in this area. As a result, livestock systems in steppe territories are up to changing to more intensive forms. These trends appear as solutions for farmers to improve their productivity in the face of various problems. Nevertheless, not to worsen the situation of livestock farming with the orientation towards the intensive system, it is important for farmers to be informed about international policies for practising intensive livestock farming. HIGHLIGHTSThe current state of livestock production and practices was identified in the steppe areas. The percentage of purchased feed had greater effects in determining the nature of the livestock systems and identifying intensive systems. The use of modelling techniques in the identification of livestock intensification could be successfully used in the differentiation of livestock systems.

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