Biological fluids such as blood, milk, fine needle aspirates, urine, and saliva from livestock play a critical role in veterinary medicine, animal husbandry, and agricultural research. These fluids serve as non-invasive or minimally invasive sources of valuable diagnostic information, enabling the monitoring of animal health, disease detection, and the assessment of physiological and metabolic states. Blood, the most widely studied fluid, provides insights into an animals overall health, immune status, and the presence of infections or metabolic disorders. Milk, particularly in dairy cattle, is crucial for assessing mammary gland health and detecting conditions like mastitis. Detection of milk somatic cells on a routine basis and keeping them low is desirable for milk and milk product quality. Fine needle aspirates (FNA) allow for the examination of specific tissues, such as lymph nodes and cancer masses, offering detailed information on cellular composition and the presence of pathological changes in cell morphology and cellular composition. Urine and saliva are increasingly recognized for their diagnostic potential. Urine analysis can reveal metabolic and kidney function and provide early indicators of systemic diseases. Saliva, being easy to collect, is a growing focus for non-invasive monitoring, hormonal changes, cancer, diseases and stress.