No Abstract provided. Please read Chapter 5: "Conclusions and recommendations" / Dissertation (MInst Agrar (Animal Production Management))--University of Pretoria, 2006. / Animal and Wildlife Sciences / unrestricted

La infertilidad en el Perú, actualmente no se encuentra considerada como una enfermedad importante para el ámbito de la salud pública, no obstante, afecta al 15% de la población en edad reproductiva y la demanda de Centros de Reproducción Asistida cada vez aumenta. Se considera que el factor masculino contribuye con el 40% de los casos como factor de infertilidad en la pareja. El análisis clínico del semen aporta al conocimiento de la calidad seminal que pueda presentar, que luego permitirá tratar a los pacientes exitosamente. El objetivo de este estudio fue evaluar la calidad seminal de pacientes con problemas de fertilidad que asistieron al Centro de Reproducción Humana de Lima (NACER) durante el periodo de Mayo del 2015 hasta Mayo del 2016. La población de estudio estuvo conformada por 150 individuos con edades comprendidas entre 27 y 70 años, a quienes se les realizó un análisis seminal, donde se evaluó parámetros seminales como volumen, viscosidad, pH, vitalidad, concentración y morfología espermática, según el manual del líquido seminal de la Organización Mundial de la Salud en su 5ta edición 2010. Se calcularon los estadísticos descriptivos, frecuencias y medias de las anomalías más frecuentes y se compararon con una condición normal en los parámetros seminales más importantes en fertilidad. Todos los análisis se realizaron con un nivel de confianza de 95% utilizando el programa SPSS versión 23 para Windows 2010, además se realizó una tabla de frecuencias que fue utilizada para obtener gráficos en excel indicando la prevalencia e incidencias de las alteraciones en los espermatogramas realizados. Del total de muestras analizadas el 50.6% presentaron por lo menos un parámetro alterado, mientras que el 49.3% de los casos están sobre los valores de referencia establecidos en la 5ta edición del manual de la OMS (2010). La astenozoospermia fue la anomalía más prevalente en los pacientes con un porcentaje de 28%, seguido de la oligozoospermia e hipospermia con un porcentaje de 19.3% en ambos casos. En las características macroscópicas se encontró que 45 (30%) de los casos evaluados presentaron anormalidades en su consistencia y el 8.6% de los casos estudiados presentaron un cuadro de azoospermia. La presencia de alteraciones como astenozoospermia, oligozoospermia, hipospermia y teratozoospermia refleja la mala calidad seminal poblacional que viene experimentando el hombre en los últimos años.Infertility in Peru is not currently considered an important disease for the field of public health; however, it affects 15% of the reproductive-age population and demand for Assisted Reproduction Centers each time increases. It is considered that the male factor contributes 40% of cases as a factor of infertility in couples. The clinical analysis of semen provides the knowledge of seminal quality that can present, that then it will allow treat patients successfully. The aim of this study was evaluate the semen quality of patients with fertility problems who attended to the Human Reproduction Center of Lima (NACER) during the period May 2015 to May 2016. The study population consisted of 150 individuals with aged between 27 and 70 years who underwent a seminal analysis, where seminal parameters was assessed such as volume, viscosity, pH, vitality, concentration and sperm morphology according to criteria of the World Health Organization (2010). Descriptive statistics, frequencies and media of the most frequent anomalies were calculated and compared with a normal condition in the most important seminal parameters in fertility. All analyzes were performed with a confidence level of 95% using SPSS version 23 for Windows 2010, also it was performed a frequency table that was used for get graphics in excel indicating the prevalence and incidence of alterations in semen analysis made. Of the total samples analyzed 50.6% showed at least one parameter altered, while 49.3% of cases fulfill the benchmarks set out in the 5th edition of the WHO manual (2010). The astenozoospermia was the anomaly most prevalent in the patients studied with a percentage of 28%, followed by oligozoospermia and hipospermia with a percentage of 19.3% each anomaly. In the macroscopic characteristics it found that 45 (30%) of cases evaluated presented abnormalities in consistency and 29% of the cases studied presented azoospermia. The presence of alterations as astenozoospermia, oligozoospermia, hipospermia and Teratozoospermia reflects the decline in semen quality population that man has experienced in recent years.

No description available.

A preliminary test was conducted evaluating the effect of digestible lysine (dLys) on broiler breeder (BB) male semen quality from forty-one to forty-nine wk of age. Five dietary treatments: corn-soybean meal diet with 1,000 mg dLys/rooser/day (Soy1,000), distillers dried grains with solubles diet with 1,000 (DDGS1,000), 850 (DDGS850), 700 (DDGS700), and 550 (DDGS550) mg dLys/rooster/day. Semen quality was similar except percentage dead sperm which was higher in DDGS550. A second trail was conducted using the same dietary treatments as the preliminary test during twenty to thirty-nine wk of age. Semen quality was similar except percentage dead sperm which was higher in Soy1,000. Soy1,000 exhibited higher body weight (BW), breast weight, and plasma testosterone. In conclusion dLys levels from 1,000 to 700 mg/rooster/day will not adversely affect semen quality of BB males. Attention should be given to BW in BB as it could lead to an increased percentage dead sperm.

In the stallion, inconsistent sexual behavior and variable semen quality are common. This reproductive variability has been attributed to differences in circulating hormone concentrations. In order to further examine this relationship, 7 miniature stallions were observed for sexual behavior and semen characteristics. Blood was also drawn from each stallion 15 min before mating (time -15), immediately following ejaculation (time 0) and at times following ejaculation (times +15, +30, and +60). Plasma was later analyzed for concentrations of testosterone (T), estrone sulphate (ES) and cortisol. Semen was evaluated for volume, sperm concentration and progressive motility. Sexual behavior was quantified by assigning a libido score to each stallion, recording reaction time and the number of jumps required for ejaculation. Upon statistical analysis, data revealed both ES and cortisol increased at the time of semen collection (P < 0.05), while T did not. Regression analysis revealed that ES and the ratio of ES to T at times -15, +30, and +60 were negatively correlated to libido scores. Additionally, a positive relationship was found between ES at times -15 and +60 and reaction time, as well as between cortisol at times -15, 0, and +15 and libido scores. No relationship was observed between T and sexual behavior. However, T at time -15 was positively correlated to progressive motility, and the ratio of ES/T at time -15 was negatively correlated to progressive motility. No other association was detected between ejaculate parameters and hormone concentrations. These results not only serve to enhance understanding of stallion hormone profiles, but also provide further insight into the hormonal control of sexual behavior and sperm production. This knowledge can be used to generate improved management techniques for stallions that are inconsistent in sexual behavior and sperm output.

The objectives of this study were to characterize residual feed intake (RFI) in growing bulls and heifers and in mid-gestation females to examine relationships with performance, body composition, feeding behavior, digestibility (DMD) and heart rate (HR) and evaluate the impact of RFI on bull fertility and cow forage utilization. Additionally, use of the n-alkane method to predict individual animal variations in intake was investigated. To accomplish these objectives, multiple RFI studies were conducted. In all studies RFI was computed as the difference between actual and expected DMI from linear regression of DMI on mid-test metabolic BW and ADG. To evaluate phenotypic relationships between feed efficiency, scrotal circumference (SC) and semen-quality an experiment was conducted with yearling bulls (N=204). Residual feed intake was not correlated with BW and ADG, but was positively associated with 12th-rib back fat (BF) such that the more efficient bulls were leaner. Bulls with low RFI had similar SC and progressive motility of sperm compared to high-RFI bulls. However percent normal sperm were weakly associated with RFI in a negative manner. To examine phenotypic relationships between heifer postweaning RFI, and performance, efficiency, HR, and DMD of mid-gestation cows, RFI was measured in growing Bonsmara heifers (N=175). Forty-eight heifers with divergent RFI were retained for breeding. Subsequently, intake, performance and feeding behavior was measured on mid-gestation females. Pregnant females classified as having low postweaning RFI continued to consume 22% less feed, spent 25% less time eating, and had 7% lower HR while maintaining similar BW, ADG and body composition compared to high RFI females. A moderate association between RFI in growing heifers and subsequent efficiency of forage utilization in pregnant cows was found. Growing heifers identified as efficient had greater DMD, however DMD in mature cows was similar between RFI groups. The n-alkane method of predicting intake detected differences in intake between divergent RFI groups in mid-gestation females. Results from this study indicate that inclusion of RFI as a component of a multi-trait selection program will improve feed efficiency of growing animals and mid-gestation females with minimal impacts on growth, body composition, and fertility traits.

Please read the abstract in the section 00front of this document / Dissertation (M Inst Agrar (Animal Production Management))--University of Pretoria, 2006. / Animal and Wildlife Sciences / unrestricted

The aim of this study was to determine the efficacy of vaccination in preventing LSDV excretion in semen and negative effects on semen quality. Lumpy skin disease (LSD) is caused by a virus in the genus Capripoxvirus of the family Poxviridae. The virus has been reported to be excreted in the semen of experimental infected nonvaccinated bulls. Nevertheless, vaccination has been the most widely used method to reduce and prevent the spread of the disease. This work was done to determine the efficacy of lumpy skin disease vaccination in preventing the excretion of lumpy skin disease virus (LSDV) in semen of experimentally infected vaccinated bulls. It also determined further the effect of vaccination and experimental infection on semen quality. Six serologically negative bulls 11-16 months of age were vaccinated with an attenuated Neethling strain of LSD vaccine, and a repeated dose of vaccine was given twenty one days later. These bulls were then experimentally infected by intravenous injection with a virulent field strain of LSDV (V248/93). Six unvaccinated bulls were similarly infected to act as controls. All animals were observed for clinical signs, blood and semen was collected and evaluated twice a week until day 40 post vaccination and every two days until day 28 post-infection when the trial was terminated. Serology was done using the serum neutralization test and viraemia was determined by virus isolation. Semen was examined by polymerase chain reaction (PCR) for the presence of virus. Semen evaluation was done visually and microscopically. Two of the unvaccinated controls developed severe LSD, two showed mild symptoms and two were asymptomatic. No clinical abnormalities were detected following vaccination, and clinical signs were limited to mild lymph node enlargement in four bulls following challenge of the vaccinated bulls. There was a significant difference (P<0.05) in semen quality after experimental infection of the unvaccinated bulls. In the vaccinated bulls, semen quality showed no significant difference (P>0.05) following vaccination and challenge. Three of the vaccinated bulls were serologically positive at the time of experimental infection and four at the end of the trial. Five unvaccinated bulls were found to be viraemic during the course of the trial. No vaccinated bulls were found to be viraemic at any stage. Four unvaccinated bulls excreted the virus in their semen during the course of the trial. Viral nucleic acid was not detected in any semen samples following vaccination or challenge in vaccinated bulls. This study provides evidence that vaccination against LSD prevented the excretion of viral particles in semen. It also illustrated that LSD vaccination prevented any effect on semen quality after experimental infection with virulent virus. / Dissertation (MSc (Production Animal Studies))--University of Pretoria, 2006. / Production Animal Studies / unrestricted

<p> Substantial economic losses occur in the swine industry during periods of high ambient temperatures. Heat stress produces physiological changes such as increased body temperature and respiration rate resulting in production losses from decreased reproductive performance, growth rate and feed intake. Heat stress in growing gilts delays puberty and decreases ovarian follicle numbers. In boars heat stress decreases semen quality. Electronically-controlled floor cooling pads were designed and constructed to assist pigs with thermoregulation by removing excess heat from pigs in a production facility. Based on this study, experiments were conducted to further investigate the effects of electronically-controlled cooling pads on physiological and reproductive performances in gilts and boars. A study was conducted on limit-fed gilts at 32°C and 35°C during short-term heat stress. Gilts exposed to short term heat stress at 32°C and 35°C had increased respiration rate, vaginal temperature and skin temperature. Gilts on electronically-controlled cooling pads exposed to short term heat stress at 35°C were able to minimize negative impacts of HS such as reduced respiration rate and vaginal temperature. A study was conducted with 24 boars which were exposed to cyclical heat stress for a duration of 3 days at 32°C and 35°C. Boars exposed to cyclical heat stress for 3 consecutive days at 32°C or 35°C which increased respiration rate and body temperature followed by a decrease in semen quality over several weeks. Boars cooled with electronically-controlled floor cooling pads had reduced physiological effects of heat stress as well as consistent semen quality post HS. The use of electronically controlled floor cooling pads have implications towards minimizing or removing the negative impacts of heat stress in gilts and boars. </p>

Background: Emerging evidence from animals indicates that oxidative stress plays a crucial role in the effects of phthalate exposure on male reproductive dysfunctions, which has never been thoroughly explored in humans. Objective: To explore the potential mediating role of oxidative stress in the association of phthalate exposure with semen quality among 1034 Chinese men. Method: Repeated urine samples gathered from the male partners of sub-fertile couples were analyzed for 3 oxidative stress markers [8-hydroxy-2-deoxyguanosine (8-OHdG), 8-iso-prostaglandin F2α (8-isoPGF2α) and 4-hydroxy-2-nonenal-mercapturic acid (HNE-MA)], using a liquid chromatography-tandem mass spectrometry. Multivariate regression models were constructed to evaluate the associations of urinary oxidative stress markers with urinary phthalate metabolites and semen quality. We also explored the potential mediation effects by oxidative stress markers. Results: Significantly positive dose-dependent relationships were observed between each individual phthalate metabolite and all analyzed oxidative stress markers (all p for trend<0.05), except for monoethyl phthalate (MEP) in relation to HNE-MA. Additionally, significantly or suggestively inverse dose-dependent relationships were exhibited between urinary 8-isoPGF2α and sperm concentration (p for trend = 0.05), and between urinary 8-OHdG and percent of normal sperm morphology (p for trend = 0.01). Mediation analysis showed that urinary 8-isoPGF2α suggestively mediated 12% of the inverse association between monobutyl phthalate (MBP) and sperm concentration, and that urinary 8-OHdG suggestively mediated 32% of the inverse association of MEP with percent of normal sperm morphology (both p < 0.10). Conclusions: Although further investigations are required, our results suggest that oxidative stress may play a mediating role in the effects of phthalate exposure on impaired semen quality.