The Haematological and Biochemical Responses of Goat Bucks to Range Grazing and Indoor Concentrate‐Based Feeding Systems

Abstract

Background Range grazing remains the principal feed resource for goats in smallholder production systems, particularly in regions where range grazing and intensive concentrate‐based systems coexist. However, expanding cropland has reduced the availability of grazing lands and shifted production toward concentrate‐based feeding systems.

Objective This study aimed to evaluate the haematological and biochemical responses of goat bucks managed under range grazing and indoor concentrate‐based feeding systems.

Methods Forty yearling bucks (10 bucks/treatment) were randomly allocated to one of four 90‐day feeding groups: range grazing (T1) or three treatments with roughage‐to‐concentrate ratios of: 60:40 (T2), 50:50 (T3) and 40:60 (T4) on a DM basis. Blood samples (10 mL/animal) were collected every fortnight via jugular vein from all bucks and were subjected to haematological and biochemical analysis.

Results Bucks in T3 and T4 had significantly (p < 0.05) greater haemoglobin, red blood cell and packed cell volume compared to T1; nevertheless, the difference between T1 and T2 was not significant. Serum protein, albumin, glucose and testosterone concentrations were also higher in bucks fed concentrate diets (p < 0.05). White blood cells, mean corpuscular volume, mean corpuscular haemoglobin concentration, the red blood cell distribution widths, globulin, aspartate aminotransferase, alanine aminotransferase, alkaline phosphatase, urea and creatinine remained unaffected (p > 0.05). Calcium level was significantly higher in T4 than T1 (p < 0.05), while K, Na, Cl and P remained unchanged (p > 0.05).

Conclusion Bucks kept indoors on concentrate‐based diets showed better oxygen‐carrying capacity, iron status, nitrogen balance and body protein reserves than bucks reared under range grazing.