India ranks as the world’s leading milk producer, with buffaloes contributing nearly half of the total output (BAHS, 2024). Among these, the Murrah buffalo is renowned for its high milk yield, adaptability to varying climatic conditions, and economic importance in the dairy sector (Marai and Haeeb,2009; Matera et al. 2022). Despite advances in nutrition, reproduction, and disease management, morphological traits of the udder remain one of the most decisive factors influencing the quantity, quality, and efficiency of milk production. Udder morphometry encompassing its shape, dimensions, and teat structure not only determines the storage capacity and ease of milk evacuation but also has a direct bearing on udder health and susceptibility to mastitis (Prasad et al. 2010; Danish et al. 2018). Shapes such as bowl and globular are generally considered ideal due to their symmetrical quarters, well-developed suspensory ligaments, and balanced teat placement, which collectively support high yields and reduce the risk of injury (Abdullah et al. 2013; Raju et al. 2022). Conversely, pendulous udders often predispose animals to mechanical injury and environmental contamination, while goaty udders, with reduced cisternal volume, tend to limit production potential (Ibrahim 2017). Teat morphology plays an equally critical role in milking efficiency and udder health. Traits such as teat length, diameter, placement, and shape influence the rate of milk flow, completeness of udder emptying, and milking comfort (Poudel et al. 2022; Kaur et al. 2017). Cylindrical teats are typically associated with optimal milking performance, whereas irregular shapes, such as pear or funnel, may impede milk let-down or predispose to teat-end hyperkeratosis. Previous studies have explored the relationship between udder conformation and milk production in various dairy breeds (Jaayid et al. 2011; Prasad et al. 2010; Poudel et al. 2022). However, comprehensive evaluations in Murrah buffaloes under organized Indian dairy farm conditions, particularly involving both udder and teat morphometry across lactation stages, remain limited. The present study was undertaken to classify Murrah buffaloes based on udder and teat shapes, record and compare detailed morphometric measurements across these categories and to evaluate their association with key milk production parameters from early to mid-lactation.

A total of 45 freshly calved Murrah buffaloes were randomly selected and maintained under uniform feeding and housing conditions. All animals were clinically healthy and free from udder abnormalities at the start of the trial. The buffaloes were visually classified into four udder shape categories (Fig. 1) like bowl, pendulous, goaty, globular (Ranjintha et al. 2021).

Teat shapes were also recorded and classified into cylindrical, conical, funnel, bottle, and pear shapes (Ranjintha et al. 2021). Figure 2 represents all 5 teat shapes found in Murrah buffaloes.

Milking was carried out twice daily at 4:00 a.m. and 4:00 p.m. using a Delaval speed line flat barn milking parlour machine milking system (16 units) under hygienic conditions. Animals were kept in holding area for at least 20–30 minutes. Holding area was fitted with automated water sprinklers and fan system with 45 seconds sprinkling followed by 5-minute fan. Pre-milking udder preparation included washing and cleaning of udder and drying of udder using paper towel before attaching teat cups.

The udder and teat morphometric parameters were recorded before milking at monthly intervals from early lactation (90 days) through mid-lactation (90days) to ensure comprehensive tracking of anatomical changes. The following traits were measured according to standardized procedures: udder width (UW) Bhuiyan et al. 2004, defined as the horizontal distance Horizontal distance across the mid-portion of the udder between the hind legs; udder height (UH), the vertical distance from the base of the udder to its point of suspension; fore udder depth (UDF) and rear udder depth (UDR) Radekar et al. 2003, representing the vertical distances from the teat base to the lowest points of the fore and rear udder attachments, respectively; teat length for both front (TLF) and rear (TLR) teats (Boselli et al. 2010), quantified from the base to the tip; teat diameter for front (TDF) and rear (TDR) teats, determined at the mid-point along the teat by measuring the circumference and calculating diameter; and horizontal distances between the centres of the front teats (DFT) and rear teats (DRT) as done by Rogers & Spencer. (1991). All measurements were carried out using a flexible measuring tape for length and circumference parameters, following established protocols to maximize precision and reproducibility. To minimize inter-observer variability, a single trained observer performed all measurements throughout the study period.

Milk yield was recorded daily for each buffalo throughout the study period. The data were compiled to calculate the following parameters: Early Lactation Milk Yield (ELMY), defined as the total milk yield from day 0 to day 90 post-calving; Mid-Lactation Milk Yield (MIDLMY), representing the total yield from day 90 to day 180 post-calving; Total Yield (TY), calculated as the cumulative milk yield across early and mid-lactation phases; and Peak Yield (PY), corresponding to the maximum daily milk yield recorded during the entire lactation period.

The findings of this investigation provide valuable insights into how specific udder and teat morphometric characteristics shape the lactational performance of Murrah buffaloes managed under uniform farm systems. Analysis revealed that Udder shape had a clear numerical influence on milk yield, with globular and bowl-shaped udders producing higher total and peak yields compared to pendulous and goaty udders. Although differences were not statistically significant, the superiority of globular and bowl udders may be attributed to symmetrical quarter development, stronger suspensory ligaments, and better teat placement, all of which contribute to increased cisternal capacity and efficient evacuation of milk. Similar observations regarding the positive association of well-developed udders with productivity have been reported earlier in buffaloes (Abdullah et al. 2013; Bharadwaj et al. 2007). On the other hand, goaty udders, characterized by uneven quarters and poor development, were consistently associated with the lowest yields, supporting earlier findings that such udder types are less desirable for milk production (Bhuiyan, 2004). Conversely, Jaayid et al. (2011) associated pendulous udders with reduced milking efficiency and higher susceptibility to mastitis. This trend, though not always statistically significant, underscores the functional advantages conferred by balanced udder quarters, robust suspensory ligaments, and optimal teat arrangement, which collectively support efficient milk storage and evacuation. Teat morphology further emerged as a pivotal determinant of performance; teat shape had a significant (p < 0.05) effect on yield parameters. Cylindrical teats showed the highest early lactation yield and total yield, followed by conical teats, while pear-shaped teats recorded the lowest performance. The superior productivity of cylindrical teats may be related to optimal teat canal morphology and uniformity, which support efficient and consistent milk flow during machine milking. Similar results were found by Ranjintha et al. (2021); Bharadwaj (2007); Abdullah et al. (2013); Poudel et al. (2022), who found that cylindrical teats facilitate more efficient milk extraction. Similarly, Kaur et al. (2017) reported that non-uniform teat shapes, such as pear or funnel, may hinder milking and increase teat-end keratin deposition. The symmetrical and uniform architecture of cylindrical teats is likely beneficial for the consistent flow of milk and complete udder emptying during machine milking. By contrast, less regular shapes such as pear and conical were associated with reduced milk extraction, which could be due to anatomical constraints affecting milk ejection or residual retention within the mammary gland. Among morphometric traits, udder width and udder depths (both front and rear) were positively correlated with milk yield, while inter-teat distances (DFT and DRT) showed negative correlations. In the pooled data, udder width exhibited a moderate positive correlation (r = 0.237, p < 0.01), while rear teat distance showed a significant negative correlation (r = − 0.173, p < 0.01). This indicates that wider udders with greater depth are associated with higher cisternal capacity and more secretory tissue, whereas excessive teat separation may hinder efficient machine milking and lead to incomplete evacuation. These observations align with previous studies linking udder size and morphology with milk yield potential in buffaloes and cattle (Jaayid et al. 2011; Danish et al. 2018). Detailed morphometric correlations in this study reinforced the importance of dimensional attributes such as udder width, fore and rear depths, and teat lengths, all of which showed positive associations with milk production, and these findings are in agreement with the findings of Jayyid et al. (2011). Importantly, excessive separation between teats, evaluated both at the fore and rear, negatively correlated with yield, potentially reflecting suboptimal cluster attachment or increased risk of inefficient milking. The effect of these relationships varied according to udder shape subgroup, suggesting that effective selection must consider not just individual traits but their coordinated expression within the context of overall udder architecture. For bowl-shaped udders, strong positive intercorrelations among udder depths, teat lengths, and teat distances indicate coordinated udder and teat conformation in bowl-shaped udders, emphasizing the structural integrity of the mammary system. For bowl-shaped udders, udder width and depth are important positive predictors of milk yield (Table 3), whereas teat lengths (both fore and rear) show no direct significant influence (Table 4). The balance of teat spacing also appears important, with wider spacing potentially detrimental to production efficiency. For goaty udders, udder width and teat lengths positively influence milk yield, while increased spacing between teats, especially measured as distance between front and rear teats, is negatively correlated with milk production (Table 8). In conclusion, these findings emphasize the importance of balanced udder and teat morphology for optimized lactation performance in this udder shape category. From a breeding and management perspective, these findings advocate for the routine integration of udder and teat morphometry into genetic selection and animal evaluation protocols. Focusing on morphometric traits such as increased udder width, balanced depths, moderate teat dimensions, and maintaining optimal inter-teat spacing, particularly in selecting for globular or bowl conformation and cylindrical teats, emerges as a practical and cost-effective route to improving milk yield and mammary health. Particular attention should also be directed toward managing third-parity buffaloes, as this group demonstrated maximal yield, reflecting optimal mammary gland maturity.

In conclusion, the study emphasizes that prioritizing favorable udder and teat conformation in Murrah buffaloes is likely to yield substantial gains in productivity and operational efficiency on Indian dairy farms. Such an approach is well-positioned to enhance not only the economic returns for producers but also sustain long-term animal health by reducing the incidence of milking-related disorders and inefficiencies. This strategy thus presents a holistic pathway for progressive herd improvement rooted in evidence-based structural evaluation.