Maintaining semen quality by improving cold chain equipment used in cattle artificial insemination

Abstract

Artificial insemination of dairy cattle is a common practice in the developing world that can improve farmer incomes and food security. Maintaining the fertilizing potential of frozen semen as it is manipulated, transported and stored is crucial to the success of this process. Here we describe simple technological improvements to protect semen from inadvertent thermal fluctuations that occur when users mishandle semen using standard equipment. We show that when frozen semen is mishandled, characteristics of semen biology associated with fertility are negatively affected. We describe several design modifications and results from thermal performance tests of several improved prototypes. Finally, we compare semen that has been mishandled in standard and improved equipment. The data suggest that our canister improvements can better maintain characteristics of semen biology that correlate with fertility when it is mishandled.

Introduction of a plasmid and a protein into bovine and swine cells by water-in-oil droplet electroporation

“…A decrease in the rate of conception is one of the doi: 10.1292/jvms.19-0475 greatest challenges especially for dairy farmers [10,18]. The low conception rate may be attributed to the fertilizing capacity of sperm [28]. To date several lines of study have attempted to improve male fertility by introducing exogenous gene fragments or proteins into sperm.…”

Using on-demand dry ice production as an alternative cryogenic cold chain for bovine artificial insemination outreach in low-resource settings1

“…Three 36 AWG T-type thermocouples (Omega, Stamford, CT) were positioned inside a blank 0.5-mL semen straw (17, 62, and 107 mm from the open end of the straw) filled with epoxy (Loctite Plastic Bonder, Westlake, OH) to secure their position. The instrumented semen straw ( Lieberman et al, 2016 ) was placed next to the bovine semen straws within each device for the duration of the in vitro experiments. Temperatures were logged using a Hobo data logger (Onset, Bourne, MA).…”

“…For each data point, a minimum of 500 sperm per straw were assessed using previously described methods ( Lieberman et al, 2016 ). Briefly, frozen semen straws were thawed in a water bath set at 35 °C for 30 s. Semen was then transferred to a 1.7-mL microcentrifuge tube and incubated at 35 °C for 1 h. Twenty microliters of semen solution was spread on a microscope slides and air-dried for 15 min.…”

A review of recent research on Theileria parva : Implications for the infection and treatment vaccination method for control of East Coast fever

“…One recent initiative which may increase the sustainability of delivery, by ultimately reducing the dependence on liquid nitrogen, involves simple modifications to the structure and handling of liquid nitrogen dewars that are designed to minimize temperature fluctuation in straws that are briefly exposed to ambient temperatures, when the flask is opened. This has worked well for improving artificial insemination by ensuring that the straws, although their contents are not thawed, do to reach the critical transition temperature of water of −137°C, which results in reorganization of water molecules and damage to membranes when the contents are returned to the liquid nitrogen (Lieberman, McClure, Harston, & Madan, ). As an extension of this work, the Seattle‐based company Intellectual Ventures is exploring the potential of keeping sporozoite stabilates on dry ice at −80, for various periods of time with support from the Intellectual Ventures Global Good Fund (funded by the Bill and Melinda Gates foundation).…”