Multinutrient blocks based on date scrap for sheep in arid areas. 3. Intake and growth performanceOriginal Title (non-English) Blocs multinutritionnels a base de rebuts de dattes pour ovins dans les zones arides 3. Ingestion et performances de croissance [French]

摘要

This work extends the previous two studies in which the physical, nutritional value and intake of Multinutrient blocks (MNB) based on date scrap (SD) were studied. It assesses the growth promoted by the three diets: R1: MNB65 (65% DS), R2: MNB35 (35% DS and 30% wheat bran) and R3: MNB358h (distributed for 8 hours, 8 am to 4 pm). The roughage was good straw quality (6% protein). It was distributed ad libitum as was drinking water. Over a 60-day period we used 6 sheep aged 18 months to measure: dry matter intake (DMI: g/per kg BW 0.75) by daily weighing of the quantities offered and refusal and daily weight gain (DWG) by weighing fasted animals each week. It appears that, as in previous studies, DMI of the blocks is important. It is 22 and 27 g respectively for R1 and R2 and 17 g for R3 (distributed for 8 hours). The presence of wheat bran in the formulation enhances the intake of blocks. The DMI of straw was similar (54 g) for R2 and R3, but lower than for R1 (68 g), which suggests the existence of phenomena of substitution when the blocks are heavily consumed. The energy value per kg DM of R1 was 0.61 lactation feed units (LFU) compared to 0.55 for R2. LFU intake was 1.11, 0.98, and 0.82 for R1, R2 and R3 respectively. The DWG for R1 was 160 g, and 100 g, and 50 g respectively for R2 and R3. By adjusting the proportion of SD and wheat bran and by modulating the block offered (ad libitum or limited), the blocks can be used to successfully contribute to feed animals such as pregnant ewes, lambs and, with some adjustment, to animal fattening.