45 research outputs found
EC97-276 Management Strategies for Pen-mating Female Pigs
The master control switch of a pork production enterprise is weaning day. Pork production managers have little or no control concerning when a weaned female will cycle or how long she will be in estrus after weaning. When females are pen-mated, the producer needs to use management procedures to prevent an excessive number of estrous females from expressing the standing response at the same time, try to manage estrous females so that they are bred at the proper time, try to manage boars so they maintain an adequate level of fertility, evaluate boars for level of sexual behavior before and during the mating period and heat-check gestating females. Regardless of the boar-to-female ratio used or the management procedures implemented, there is no guarantee all females will be satisfactorily serviced during their first estrus after weaning
Heterospermic Insemination in Swine
The studies report herein were conducted to evaluate (1) if there is a difference in pregnancy rate and litter size in swine between heterospermic and homospermic inseminations, (2) the effect of mixing various fresh cm n components involving spermatozoa in the sperm-rich fraction, seminal plasma from the centrifuged post-sperm fraction and Beltsville Ll extender on oxygen consumption, pH, motility and percent dead spermatozoa and (3) the effect of storage (54 hours) on oxygen consumption, pH, motility and percent dead spermatozoa in the various combinations. One Hampshire and one Yorkshire boar were used in the pregnancy rate and litter size study
The Effect of Photoperiod on Sexual Development in Young Boars
The effects of photoperiod in stimulating reproductive function in prepubertal boars was studied in 40 crossbred boars. One group of boars was exposed to a regimen where day length was increased from 12 to 14.5 h/d (from 8 to 20 weeks of age) and then decreased from 14.5 to 12 h/d (from 20 to 32 weeks of age); whereas, the other group of boars was exposed to a regimen where day length was decreased from 12 to 9.5 h/d and then increased from 9.5 to 12 h/d. Exposing prepubertal boars to a long photoperiod inhibited the development of the testis at 24 weeks of age. The inhibitory effect of long days on testis development at 24 weeks of age was overcome by decreasing the photoperiod. Short days reduced the level of sexual behavior at 25 and 26 weeks of age. The inhibitory effects of short days on sexual behavior was overcome by exposing boars to a longer period. This study implies that young boars reared during short days may need to be exposed to a longer photoperiod before expressing an adequate level of sexual behavior and young boars reared during long days may need to be exposed to shorter days to increase their sperm production capability
Poly-epsilon-lysine based hydrogels as synthetic substrates for the expansion of corneal endothelial cells for transplantation
Patterns of patient-reported symptoms and association with sociodemographic and systemic sclerosis disease characteristics: a scleroderma Patient-centered Intervention Network (SPIN) Cohort cross-sectional study
Background Systemic sclerosis is a heterogenous disease in which little is known about patterns of patient-reported symptom clusters. We aimed to identify classes of individuals with similar anxiety, depression, fatigue, sleep disturbance, and pain symptoms and to evaluate associated sociodemographic and disease-related characteristics.
Methods This multi-centre cross-sectional study used baseline data from Scleroderma Patient-centered Intervention Network Cohort participants enrolled from 2014 to 2020. Eligible participants completed the PROMIS-29 v2.0 measure. Latent profile analysis was used to identify homogeneous classes of participants based on patterns of anxiety, depression, fatigue, sleep disturbance, and pain scores. Sociodemographic and disease-related characteristics were compared across classes.
Findings Among 2212 participants, we identified five classes, including four classes with āLowā (565 participants, 26%), āNormalā (651 participants, 29%), āHighā (569 participants, 26%), or āVery Highā (193 participants, 9%) symptom levels across all symptoms. Participants in a fifth class, āHigh Fatigue/Sleep/Pain and Low Anxiety/Depressionā (234 participants, 11%) had similar levels of fatigue, sleep disturbance, and pain as in the āHighā class but low anxiety and depression symptoms. There were significant and substantive trends in sociodemographic characteristics (age, education, race or ethnicity, marital or partner status) and increasing disease severity (diffuse disease, tendon friction rubs, joint contractures, gastrointestinal symptoms) across severity-based classes. Disease severity and sociodemographic characteristics of āHigh Fatigue/Sleep/Pain and Low Anxiety/Depressionā class participants were similar to the āHighā severity class.
Interpretation Most people with systemic sclerosis can be classified by levels of patient-reported symptoms, which are consistent across symptoms and highly associated with sociodemographic and disease-related variables, except for one group which reports low mental health symptoms despite high levels of other symptoms and substantial disease burden. Studies are needed to better understand resilience in systemic sclerosis and to identify and facilitate implementation of cognitive and behavioural strategies to improve coping and overall quality of life
Yeast targets for mRNA methylation
N6-Methyladenosine (m6A) is a modified base present in the mRNA of all higher eukaryotes and in Saccharomyces cerevisiae, where there is an increase in m6A levels during sporulation. The methyltransferase, Ime4, is responsible for this modification and has a role in the initiation of meiosis. However, neither the function, nor the extent of distribution of this nucleotide modification is established. We demonstrate that in S. cerevisiae, substantial levels of internal adenosine methylation are present in the GpA context in mRNA from sporulating cells, which is consistent with the preferred methylation consensus of higher eukaryotes. Based upon our quantification data, every second transcript could contain one m6A during meiosis. As methylation is distributed across all mRNA size ranges, it is likely that m6A is not limited to a small population of messages. We developed a new antibody based method for identifying m6A containing messages, and using this method the transcripts of three key, early regulators of meiosis, IME1, IME2 and IME4 itself, were identified as being methylated. The position of m6A in IME2 was narrowed down to a region in the 3ā²-end. Methylation of these and other targets suggests mechanisms by which IME4 could control developmental choices leading to meiosis
EC85-219 1985 Nebraska Swine Report
This 1985 Nebraska Swine Report was prepared by the staff in Animal Science and cooperating departments for use in the Extension and Teaching programs at the University of Nebraska-Lincoln. Authors from the following areas contributed to this publication: Swine Nutrition, swine diseases, pathology, economics, engineering, swine breeding, meats, agronomy, and diagnostic laboratory. It covers the following areas: breeding, disease control, feeding, nutrition, economics, housing and meats
The Effect of Oxytocin at the Time of Insemination on Reproductive Performance ā A Review
Oxytocin is released from the brain of the sow at the time of mating in response to stimulation by the boar. It is assumed that it enhances sperm transport to the oviduct. Several investigators have studied whether injecting oxytocin into semen before artificial insemination improves farrowing rate and litter size. The conclusions from review of these studies are: 1) Adding 4 to 5 IUās of oxytocin to a dose of semen improves farrowing rate and litter size; 2) Use of oxytocin-treated semen is more effective in multiparous sows than gilts; 3) During the summer months, oxytocin-treated semen significantly increased farrowing rate and litter size; and 4) In most studies, the use of oxytocin at the time of insemination was profitable. Oxytocin should be added to the semen with an insulin syringe immediately before attaching the semen vessel to the insemination catheter