Date of Graduation
12-2025
Document Type
Thesis
Degree Name
Bachelor of Science in Agriculture
Degree Level
Undergraduate
Department
Animal Science
Advisor/Mentor
Dr. Brittni Littlejohn
Committee Member
Dr. Jeremy Powell
Second Committee Member
Dr. Tsung Cheng Tsai
Abstract
Feral swine are an invasive species in the United States that negatively impact native ecosystems, agricultural operations, and the national economy, as well as livestock, companion animal, and human health. Despite heavy investments on the individual, state, and national levels, the feral swine population continues to increase annually. Gossypol is a polyphenolic compound found in the cottonseed plant that has been found to negatively impact fertility in males of various species. The objective of this study was to determine the influence of gossypol- containing cottonseed oil supplemented to domestic boars on various semen quality parameters and body weight as a model for feral hog reproductive control. Sexually mature boars (n = 18) were stratified by body weight and parentage into 4 treatment groups. The 4 treatment groups were supplemented with cottonseed oil containing varying concentrations of gossypol: 0 mg/kg of bodyweight (0G), 4 mg/kg of body weight (4G), 8 mg/kg of body weight (8G), or 12 mg/kg of body weight (12G). A mixture of gossypol-free cottonseed oil (Riceland Foods, Inc.; Stuttgart, AR) and gossypol-containing cottonseed oil with known concentrations was prepared for each treatment group. Treatments were administered for a 42-day period, followed by a 70- day recovery period. During the recovery period, all boars were fed a diet that did not contain any cottonseed oil. Semen collections were performed biweekly during both the treatment and recovery periods. Parameters evaluated included sperm motility, sperm progressive motility, concentration of sperm cells per mL of semen, semen weight, semen volume, and body weight. Data analysis showed that percent motility and progressive motility of sperm had a treatment by time interaction (P < 0.01). Percent motility and progressive motility decreased in the 4G, 8G, and 12G treatment groups relative to the 0G treatment group by day 42 of the treatment period and returned to similar percentages as the 0G treatment group by day 70 of the recovery period. Concentration was affected by treatment (P = 0.02) and time (P = 0.01). The 8G treatment group had decreased concentration relative to the 0G treatment group. There was no treatment by time interaction for concentration (P = 0.93). There was a treatment by time interaction (P = 0.02) and effect of time (P < 0.01) for body weight. Boars in the 12G treatment group gained less weight over time relative to the 0G, 4G, and 8G treatment groups, likely due to palatability issues and decreased feed intake associated with the high concentration of gossypol in the diet fed to this group. There was no effect of treatment (P = 0.28) on body weight. There was no effect of time, treatment, or the treatment by time interaction on semen weight (P > 0.05). There were some fluctuations in semen volume over time (P = 0.05). However, there was no effect of treatment (P = 0.27) or a treatment by time interaction (P = 0.44). The results of decreased sperm motility, progressive motility, and concentration in boars supplemented with gossypol-containing cottonseed oil support the potential for gossypol-containing cottonseed oil to be utilized as a contraceptive in feral boars.
Keywords
Swine; Reproduction; Contraceptive
Citation
Turner, Z. A. (2025). Influence of Gossypol from Cottonseed Oil on Semen Quality in Domestic Boars as a Model for Feral Hog Control. Animal Science Undergraduate Honors Theses Retrieved from https://scholarworks.uark.edu/anscuht/84
