Reproduction, Fertility and Development Reproduction, Fertility and Development Society
Vertebrate reproductive science and technology
RESEARCH ARTICLE

Sperm function during incubation with oestrus oviductal fluid differs in bulls with different fertility

A. Kumaresan A B , A. Johannisson A and A.-S. Bergqvist A C

A Division of Reproduction, Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, PO Box 7054, SE-750 07 Uppsala, Sweden.

B Present address: Theriogenology Laboratory, Animal Reproduction, Gynaecology and Obstetrics, National Dairy Research Institute, Karnal, 132001 Haryana, India.

C Corresponding author. Email: ann-sofi.bergqvist@slu.se

Reproduction, Fertility and Development - https://doi.org/10.1071/RD15474
Submitted: 14 November 2015  Accepted: 1 March 2016   Published online: 26 April 2016

Abstract

Spermatozoa undergo several modifications in the oviduct before acquiring fertilising capacity. Although spermatozoa are exposed to similar conditions in the oviduct, the speed of the response varies with the male and the state of the spermatozoa. We hypothesised that spermatozoa from bulls with different fertility may differ in their ability to respond to oviductal fluid (ODF). Frozen–thawed spermatozoa from four bulls were incubated with oestrus oviductal fluid (OODF) for 6 h. Sperm kinematics, tyrosine phosphorylation, phosphorylation patterns, capacitation and acrosome reaction were analysed at hourly intervals. The amplitude of lateral head displacement (ALH) and straightness coefficient (STR) were higher (P < 0.05) in bulls with higher fertility compared with those with lower fertility, at 1–4 h of incubation. At 4 h of incubation and onwards, spermatozoa from bulls with higher fertility showed a lower degree (P < 0.05) of tyrosine phosphorylation and higher degree of capacitation and acrosome reaction. At least five tyrosine-phosphorylated sperm proteins were detected in all bulls. However, the expression of two phosphorylated sperm proteins (183 and 109 kDa) was upregulated in bulls with lower fertility. It may be concluded that cryopreserved spermatozoa from high- and low- fertile bulls differ in their ability to respond to OODF. This may help in developing tools for assessing fertility of bulls, once validated in more animals.

Additional keywords: acrosome reaction, bovine, capacitation, tyrosine phosphorylation.


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