Identification of protein candidates in spermatozoa of water buffalo (Bubalus bubalis) bulls helps in predicting their fertility status

Abstract

The water buffalo (Bubalus bubalis) is an indispensable part of the Indian dairy sector and in several instances, the farmers incur economic losses due to failed pregnancy after artificial insemination (AI). One of the key factors for the failure of conception is the use of semen from the bulls of low fertilizing potential and hence, it becomes important to predict the fertility status before performing AI. In this study, the global proteomic profile of high fertile (HF) and low fertile (LF) buffalo bull spermatozoa was established using a high-throughput LC-MS/MS technique. A total of 1,385 proteins (≥1 high-quality PSM/s, ≥1 unique peptides, p < 0.05, FDR < 0.01) were identified out of which, 1,002 were common between both the HF and LF groups while 288 and 95 proteins were unique to HF and LF groups respectively. We observed 211 and 342 proteins were significantly high (log Fc ≥ 2) and low abundant (log Fc ≤ 0.5) in HF spermatozoa (p < 0.05). Gene ontology analysis revealed that the fertility associated high abundant proteins in HF were involved in spermatogenesis, sperm motility, acrosome integrity, zona pellucida binding and other associated sperm functions. Besides this, the low abundant proteins in HF were involved in glycolysis, fatty acid degradation and inflammation. Furthermore, fertility related differentially abundant proteins (DAPs) on sperm viz., AKAP3, Sp17, and DLD were validated through Western blotting and immunocytochemistry which was in coherence with the LC-MS/MS data. The DAPs identified in this study may be used as potential protein candidates for predicting fertility in buffaloes. Our findings provide an opportunity in mitigating the economic losses that farmers incur due to male infertility.

Regression coefficient of semen characteristics of buffalo bulls on seminal plasma proteins

“…Still, details concerning their presence in seminal plasma, their significance in sperm metabolism, and their relation to bull fertility were not investigated extensively [8, 9,10]. The proteins in seminal plasma have an essential role in sperm protection, their capacitation inside the female reproductive tract, acrosome reaction, sperm-egg binding, and early conception and embryonic development [11,12]. Detection of seminal proteins for good and bad semen will provide further details concerning the early prediction of buffalo bull fertility via their role in sperm metabolism.…”

Effect of Melatonin Implantation on Sexual Behavior and some of Semen Quality of Iraqi Buffalo Bulls

“…Therefore, the semen of buffaloes is more susceptible to lipid oxidative damage by reactive oxygen species (ROS), which leads to an increase in the percentage of abnormalities, damage to the genetic material, and a decrease in fertility [9,10]. Buffalo bulls are characterized by a lack of sperm concentration, motility, viability, a weak sperm mitochondrial membrane, and maturation within the epididymis [11]. The effects of reactive oxygen species on the semen of buffalo bulls appear during spermatogenesis and cryopreservation [6,10,12,13].…”

“…In semen, free radicles or ROS are generated by leukocytes, dead, abnormal, and immature spermatozoa. Buffalo bulls are characterized by a lack of sperm concentration, motility, and viability, a weak sperm mitochondrial membrane, and maturation within the epididymis [12]. The effects of free radicals or ROS on the semen of buffalo bulls appear during spermatogenesis and cryopreservation [6,11,13,14].…”

Protein Profiles in Seminal Plasma of Iraqi Buffalo Bulls (Bubalus bubalis) Associated with Fresh and Cryopreserved Semen Quality

“…The field fertility of bulls is affected depending on the pregnancy rate of cows and buffaloes by several factors, including the health status of the bulls, genetic characteristics, the capacity of the reproductive organs, herd management, semen quality, and the steps used for sperm cryopreservation [1,3,4,5,6]. On the other hand, biomarkers such as various proteins play an essential role in the biological systems of bulls, but detailed information about their presence in seminal plasma, their importance in sperm metabolism, and their relationship to the fertility of buffalo bulls have not been widely studied [7][8][9][10][11]. The seminal proteins play principal roles in sperm protection, capacitation, acrosome reaction, spermegg binding, fertilization, and early embryonic development [12].…”