Animal welfare is an important aspect to consider in the cattle industry. Enhancing their quality of life on the farm is essential for ethical and sustainable farming practices. A key focus area is understanding the affective states of these animals - how they feel and their emotional well-being, particularly in the case of cows. While significant advancements have been made in studying human emotions and behaviors using technologies such as machine learning, computer vision, and various sensors, research into animal emotions is still evolving. Researchers from multiple disciplines, such as neuroscience and animal welfare science, strive to better understand animal affective states and emotions. Although the direct assessment of emotions in animals remains challenging, indicators such as neural, behavioral, and physiological responses provide valuable insights into their well-being. Leveraging computer vision to study these indicators can help improve the welfare of dairy cows, ultimately enhancing productivity and boosting the livelihoods of small- and medium-scale farmers.