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The objective of the current study was to determine the fatty acid composition of sperm from Holstein bulls with different freezability (Good and Poor; n = 12). Fatty acids were extracted from frozen sperm in 1:2 (v/v) chloroform–methanol solvent, fractionated into neutral and polar fractions, and composition determined by gas chromatography–mass spectrometry. Thirty-four fatty acids were quantified and their concentrations and percentages within each lipid fraction were calculated. Overall, saturated fatty acids (SFA) were predominant, accounting for 71 to 80% of fatty acids in neutral and polar lipid factions. There were marked differences in fatty acid composition between the lipid fractions (P < 0.001). The branched chain fatty acid (BCFA) concentration (15 to 18 µg) was almost twice as much as polyunsaturated fatty acids (PUFA) concentration found in the polar lipid fraction (8 to 9 µg; P < 0.001). Sperm with different freezability phenotypes only had a few differences in 22:0, 18:1 cis 9, and 14:0 13-methyl fatty acids (P ≤ 0.011). These results are significant because they reveal key understandings of fatty acid composition of sperm membrane and lay a foundation for the manipulation of membrane integrity, fluidity, and stability to advance the assisted reproductive technologies.

The running walk of the Tennessee Walking Horse is often described as a faster variation of the walk, indicating the importance of velocity on the mechanics of the gait. Variations in gait variables create difficulties in clearly identifying the normal and abnormal running walk in a clinical evaluation. The objectives of this study were, therefore, to describe the flat shod running walk and to determine the relationship between velocity and the running walk. From frame-by-frame analysis of 60 Hz film, temporal variables were averaged for 6 strides from 6 horses performing an 'easy' (slow) and 'strong' (fast) running walk during a flat shod, easy-rider Tennessee Walking Horse show class. The running walk at both velocities was a 4-beat, symmetrical stepping gait with a lateral footfall sequence and lateral couplets. The velocity ranged from mean +/- s.d. 2.66 +/- 0.34 to 3.80 +/- 0.18 m/s. For both velocities (slow, fast), hind stance as a percentage of stride duration (58 +/- 3%, 56 +/- 2%) was significantly longer than fore (51 +/- 5%, 48 +/- 1%); diagonal advanced placement (29 +/- 2%, 37 +/- 4%) and lift-off (35 +/- 5%, 39 +/- 2%) were significantly longer than lateral (advanced placement: 22 +/- 2%, 12 +/- 3%; lift-off: 18 +/- 4%, 10 +/- 2); and lateral bipedal support (50 +/- 9%, 67 +/- 7%) was significantly longer than diagonal (27 +/- 6%, 16 +/- 4%). Strong correlations were found between velocity and diagonal advanced placement (0.640), lateral lift-off (-0.924) and diagonal (-0.648) and lateral (0.904) bipedal support. Understanding the running walk and the gait variations due to velocity may be important to both the performance and soundness of the Tennessee Walking Horse.

Developing a deeper understanding of biological components of sperm is essential to improving cryopreservation techniques and reproductive technologies. To fully ascertain the functional determinants of fertility, lipidomic methods have come to the forefront. Lipidomics is the study of the lipid profile (lipidome) within a cell, tissue, or organism and provides a quantitative analysis of the lipid content in that sample. Sperm cells are composed of various lipids, each with their unique contribution to the overall function of the cell. Lipidomics has already been used to find new and exciting information regarding the fatty acid content of sperm cells from different species. While the applications of lipidomics are rapidly evolving, gaps in the knowledge base remain unresolved. Current limitations of lipidomics studies include the number of available samples to analyze and the total amount of cells within those samples needed to detect changes in the lipid profiles across different subjects. The information obtained through lipidomics research is essential to systems and cellular biology. This review provides a concise analysis of the most recent developments in lipidomic research. This scientific resource is important because these developments can be used to not only combat the reproductive challenges faced when using cryopreserved semen and artificial reproductive technologies in livestock such as cattle, but also other mammals, such as humans or endangered species.

Equine assisted learning (EAL) is a form of experiential learning that is quickly growing in interest within the educational community. A challenge with experiential learning programs for at-risk youth is creating an emotionally safe environment that opens up the participants to learning. Nevertheless, EAL has been credited with the development of life skills in youth that promote educational achievement, but research tracking the development of emotional safety and learning, specifically associated with programming dedicated to educating participants about the horse, is limited. Therefore, the objective of this study was to determine if EAL, with programming centered around equine education, will promote emotional safety and learning in at-risk youth. Youth labeled as at-risk participated in a 4-week EAL session focused on teaching participants horse behavior, management, handling, and riding, while incorporating the 4 themes of emotional safety (self-esteem, personal security, respect, and connectivity). To determine participant learning of the equine topics covered, a pre- and post-program test was given to each participant. Acquirement of the themes of emotional safety was tracked for each participant using weekly debriefing interviews. While this was the first time to perform this assessment protocol for evaluating learning and emotional safety in at-risk youth, the completion rate for both forms of assessment utilized in this study was 100%. Evaluation of debriefing interview answers and test scores from the equine knowledge questions showed improvement by the end of the session in both equine knowledge and emotional safety, particularly as it relates to personal security. These results suggest EAL, with programming directed towards educating the participant about the horse, promotes emotional safety and learning for at-risk youth.