Some Physiological and Immunological Responses of Growing Barki Lambs Fed on Biologically Treated Trimming Waste of Mandarin Trees in Siwa Oasis

Abstract

This study aimed to evaluate the effects of replacing traditional roughage with trimming waste of mandarin trees (TWMT), either untreated or biologically treated with Bio-Magic (BM), on thermorespiratory responses, hematological, biochemical, thyroid hormonal profiles, and immunological status of growing Barki lambs under the environmental conditions of Siwa Oasis. Thirty-three weaned Barki lambs (aged 5 months, average weight 31.56 ± 0.48 kg) were randomly assigned to three experimental groups (11 lambs per group) for a 4-month trial. The control group (CR) received Berseem Hay (BH) + Concentrate Feed Mixture (CFM). The untreated group (UR) was fed TWMT + CFM. The treated group (TR) received TWMT + CFM biologically treated with Bio-Magic at a rate of 10 kg fresh 
matter/ton CFM. Feed was offered as 70% CFM of total requirements, with roughage provided ad libitum. The results showed that biological treatment (TR) significantly reduced skin temperature, respiration rate, and heart rate compared to the control group, indicating improved thermal comfort and heat adaptability in Siwa Oasis conditions. Lambs in the TR group showed a significant increase in RBC count (8.24×106 / mm3), Hemoglobin (11.15 g dL-1), and PCV% (30.37%), as well as total WBCs count (11.59× 103/ cells / mm3) compared to UR and CR groups. TR significantly elevated Total Protein (8.55 g dL-1) and Albumin (4.19 g dL-1), while maintaining normal globulin levels. Thyroid hormones (T3 and T4) were significantly higher in the TR group (5.89 ng mL-1 and 98.70 ng mL-1) respectively, indicating enhanced metabolic rate and nutrient utilization. Liver enzymes (ALT, AST, GGT, Alk. Ph) and kidney markers (Creatinine and Urea) remained within healthy physiological ranges, showing a slight decrease in blood urea, which reflects improved ruminal nitrogen utilization efficiency without any systemic toxicity. TR significantly enhanced Immunoglobulin G (IgG: 2.33 ng mL-1), Total Antioxidant Capacity (TAC: 0.90 nmol mL-1), and Interleukins (IL-2 and IL-6) compared to untreated and control rations. Lipid parameters (Total Lipids, Total Cholesterol, HDL, and LDL) were significantly decreased in TWMT-fed groups (TR and UR), likely due to the active phytochemicals (flavonoids and tannins) present in mandarin residues. Conclusion: Utilizing biologically treated trimming waste of mandarin trees (TWMT + Bio-Magic) as a non-conventional roughage source can successfully replace traditional roughages. It improves growth performance, metabolic efficiency, antioxidant activity, and immune response without adverse effects on liver or kidney functions, offering an eco-friendly and cost-effective feeding strategy in arid region oasis conditions.