Blood sample collection in small laboratory animals is essential for various scientific research studies. The article outlines approved techniques for blood collection in rodents, lagomorphs, and nonrodents, emphasizing the need for methods that minimize stress and pain. It highlights the importance of following guidelines from regulatory agencies and obtaining approval from the Institute Animal Ethics Committee. General principles include ensuring the method is least painful, training for proper technique, and limiting blood collection to safe volumes. For nonrodents, a maximum of 10% of total blood volume can be collected, with fluid replacement if necessary. Techniques such as saphenous vein, tail vein, orbital sinus, and jugular vein are described, along with procedures for temporary cannula use and terminal methods like cardiac puncture. Each method has specific requirements and precautions to ensure the animal's welfare and the accuracy of results. The article also discusses the importance of proper labeling, limiting the number of attempts, and maintaining aseptic conditions to prevent complications. Overall, the focus is on ethical and effective blood collection practices in laboratory animals.Blood sample collection in small laboratory animals is essential for various scientific research studies. The article outlines approved techniques for blood collection in rodents, lagomorphs, and nonrodents, emphasizing the need for methods that minimize stress and pain. It highlights the importance of following guidelines from regulatory agencies and obtaining approval from the Institute Animal Ethics Committee. General principles include ensuring the method is least painful, training for proper technique, and limiting blood collection to safe volumes. For nonrodents, a maximum of 10% of total blood volume can be collected, with fluid replacement if necessary. Techniques such as saphenous vein, tail vein, orbital sinus, and jugular vein are described, along with procedures for temporary cannula use and terminal methods like cardiac puncture. Each method has specific requirements and precautions to ensure the animal's welfare and the accuracy of results. The article also discusses the importance of proper labeling, limiting the number of attempts, and maintaining aseptic conditions to prevent complications. Overall, the focus is on ethical and effective blood collection practices in laboratory animals.