Treatment of Acute Kidney Injury: A Review of Current Approaches and Emerging Innovations

Acute kidney injury (AKI) is a complex and life-threatening condition with multifactorial etiologies, ranging from ischemic injury to nephrotoxic exposures. Management is founded on treating the underlying cause of AKI, but supportive care-via fluid management, vasopressor therapy, kidney replacement therapy (KRT), and more-is also crucial. Blood pressure targets are often higher in AKI, and these can be achieved with fluids and vasopressors, some of which may be more kidney-protective than others. Initiation of KRT is controversial, and studies have not consistently demonstrated any benefit to early start dialysis. There are no targeted pharmacotherapies for AKI itself, but some do exist for complications of AKI; additionally, medications become a key aspect of AKI management because changes in renal function and dialysis support can lead to issues with both toxicities and underdosing. This review will cover existing literature on these and other aspects of AKI treatment. Additionally, this review aims to identify gaps and challenges and to offer recommendations for future research and clinical practice.

Measures to Increase Immunogenicity of SARS-CoV-2 Vaccines in Solid Organ Transplant Recipients: A Narrative Review

Purpose of review: To review the data on the immunogenicity of COVID-19 vaccines, administered by different strategies, in solid organ transplant recipients (SOTRs). Recent findings: COVID-19 booster vaccines were given to SOTRs as a widespread practice in many transplant centers, mostly as the third and/or fourth dose in an extended vaccine series, with a significantly improved humoral response compared with the initial two-dose scheme. However, one-third of SOTRs remained unresponsive, despite these boosters. Next steps: Vaccination with standard dosing remains the most feasible strategy for attaining protection against COVID-19. Additional booster doses and temporarily holding or reducing mycophenolate mofetil/mycophenolic acid may provide immunogenicity to vaccines, according to recent studies demonstrating some efficacy with these measures. Preexposure prophylaxis with monoclonal antibodies showed benefit in immunocompromised patients but is no longer recommended by the National Institutes of Health (NIH) due to diminished efficacy against Omicron and recent variants. Screening for the presence and titers of SARS-CoV-2-specific antibodies in SOTRs is not recommended in most clinical settings. T cell-based techniques are needed to evaluate vaccine efficacy and risk of infection. As SARS-CoV-2 continues to evolve, new vaccines based on conservative protein component/complexes of the COVID virus, in addition to its spike protein, are warranted to offer prolonged protection.

Effect of arachidonic acid on pre- and post-hatching in vitro bovine embryo development

CONTEXT

Arachidonic acid (AA) is the precursor of prostaglandins, which may play autocrine roles during early embryo development.

AIMS

To test the developmental effects of addition of AA to pre- and post-hatching culture media on in vitro-produced bovine embryos.

METHODS

Pre-hatching effects of AA were tested by culturing bovine zygotes in synthetic oviductal fluid (SOF) supplemented with 100 or 333μM AA. Post-hatching effects of AA were tested by culturing Day 7 blastocysts in N2B27 supplemented with 5, 10, 20 or 100μM AA up to Day 12.

KEY RESULTS

Pre-hatching development to blastocyst was completely abrogated at 333μM AA, whereas blastocyst rates and cell numbers were not altered at 100μM AA. Impaired post-hatching development was observed at 100μM AA, whereas no effect on survival rates was noted at 5, 10 and 20μM AA. However, a significant reduction in Day 12 embryo size was observed at 10 and 20μM AA. Hypoblast migration, epiblast survival and formation of embryonic-disc-like structures were unaffected at 5-10μM AA. AA exposure downregulated the genes PTGIS, PPARG, LDHA and SCD in Day 12 embryos.

CONCLUSIONS

Pre-hatching embryos are mostly irresponsive to AA, whereas AA was observed to have negative effects during early post-hatching development.

IMPLICATIONS

AA does not improve in vitro bovine embryo development and is not required up to early post-hatching stages.

Use of the flavonoid taxifolin for sperm cryopreservation from the threatened Bermeya goat breed

Taxifolin is a plant flavonoid effective as an antioxidant. This study aimed to assess the effect of adding taxifolin to the semen extender during the cooling period before freezing on the overall post-thawing sperm variables of Bermeya goats. In the first experiment, a dose-response experiment was performed with four experimental groups: Control, 10, 50, and 100 μg/ml of taxifolin using semen from 8 Bermeya males. In the second experiment, semen from 7 Bermeya bucks was collected and extended at 20 °C using a Tris-citric acid-glucose medium supplemented with different concentrations of taxifolin and glutathione (GSH): control, 5 μM taxifolin, 1 mM GSH, and both antioxidants. In both experiments, two straws per buck were thawed in a water bath (37 °C, 30 s), pooled, and incubated at 38 °C. Motility (CASA) was assessed at 0, 2, and 5 h, and sperm physiology was assessed at 0 and 5 h by flow cytometry (viability, intact acrosome membrane, mitochondria membrane potential, capacitation, intracellular reactive oxygen species -ROS-, mitochondrial superoxide, and chromatin status). In experiment 2, an artificial insemination trial (AI) was included with 29 goats for testing the taxifolin 5-μM treatment on fertility. Data were analyzed with the R statistical environment using linear mixed-effects models. In experiment 1 and compared to the control, T10 increased progressive motility (P < 0.001) but taxifolin decreased total and progressive motility at higher concentrations (P < 0.001), both post-thawing and after the incubation. Viability decreased post-thawing in the three concentrations (P < 0.001). Cytoplasmic ROS decreased at 0 and 5 h at T10 (P = 0.049), and all doses decreased mitochondrial superoxide post-thawing (P = 0.024). In experiment 2, 5 μM taxifolin or 1 mM GSH (alone or combined) increased total and progressive motility vs. the control (P < 0.01), and taxifolin increased kinematic parameters such as VCL, ALH, and DNC (P < 0.05). Viability was not affected by taxifolin in this experiment. Both antioxidants did not significantly affect other sperm physiology parameters. The incubation significantly affected all the parameters (P < 0.004), overall decreasing sperm quality. Fertility after artificial insemination with doses supplemented with 5 μM taxifolin was 76.9% (10/13), not significantly different from the control group (69.2%, 9/13). In conclusion, taxifolin showed a lack of toxicity in the low micromolar range and could benefit goat semen cryopreservation.

Medical student readiness to treat LGBTQ patients

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Background: The lesbian, gay, bisexual, transgender and queer (LGBTQ) community experiences cancer health disparities. It is thus imperative that medical trainees receive training in the care of LGBTQ populations. Identifying gaps in trainees’ knowledge and comfort in providing care for this population is important in preparing future physicians. Methods: A Likert-scale survey of US medical students at three institutions assessed attitudes, comfort and knowledge in providing care for LGBTQ patients. Results were quantified with descriptive and stratified analyses. Exploratory factor analysis found four factors in which attitude summary measure (ASM) scores were calculated; lower values indicate more agreeability with given attitude items. Total knowledge scores were calculated with higher values indicating greater knowledge. Results: Of 300 medical students who completed the survey, the majority were female (55.7%), white (54.7%), and heterosexual (64.3%). The majority of students felt comfortable (strongly agree/agree) participating in the care of patients who identify as lesbian (94.3%), gay (96.0%), and bisexual (96.3%); this percentage dropped to 82.3% for non-binary and 71.3% for transgender patients. Only 27.0% of students reported confidence in their knowledge of health needs of transgender patients. LGBTQ self-identification, percent of core rotations completed, and having LGBTQ friends/family were significantly associated with various ASM subscales (Table 1). Knowledge questions had high percentages of “neutral” responses, and students who identified as LGBTQ had significantly higher total knowledge scores. Conclusions: Overall, medical students feel comfortable and willing to provide care for LGBTQ patients. However, as in our prior study in oncologists, there is limited knowledge about specific LGBTQ health and cancer needs. More education and training in the needs of transgender and non-binary patients is indicated. [Table: see text]

Abstract PO-063: Medical students' knowledge and comfort in participating in cancer prevention for LGBTQ+ patients

Background: The majority of US medical schools have a required curriculum related to the care of LGBTQ+ people, which varies in length and content across schools. All medical specialties and sub-specialties have a component of need for cancer care; either in prevention, treatment, or care planning. As such, it is imperative that medical trainees receive relevant training in the care of LGBTQ+ populations, a community experiencing significant cancer health disparities. Assessing trainees' knowledge and confidence in providing care is an important aspect of preparing the next generation of physicians. Methods: This abstract reports on survey results from 3 US medical schools (New York University, University of Miami, University of Texas San Antonio) assessing the knowledge, attitudes and comfort in providing care for LGBTQ+ people. The survey was comprised of 54 Likert response (1=strongly disagree; 7=strongly agree) choice questions on: attitudes (30), knowledge (10), student demographics (13) and desire for additional LGBTQ+ education (1). Results were analyzed using descriptive and quantitative analyses. Results: A total of 360 medical students completed the survey and analyses revealed the majority of students had positive attitudes towards caring for LGBTQ+ patients, but lacked comfort in providing care for transgender/non binary patients (TNB) in general (p=0.05); specific cancer prevention care for TNB (p&lt; 0.01); reproductive care for TNB (p&lt; 0.01) and sexual heath (p=0.01). There was a significant correlation between high knowledge scores and comfort in asking a patient's pronouns (p&lt;0.01). More than 80% felt comfortable discussing cancer prevention care with LGB patients and 75% believed it was important to know the sexual orientation of patient to provide the best care. Eighty percent agreed there should be mandatory LGBTQ+ education in medical school. As in our prior studies, total knowledge scores did not correlate with attitudes. Conclusions: Medical students feel comfortable and willing to provide cancer prevention care for LGB patients but may need more education and training in the unique needs of TNB patients. Medical schools should consider specific education in cancer prevention and treatment for TNB populations.

Citation Format: Gwendolyn P. Quinn, Christina Tamargo, Devin Murphy, Megan Sutter, Lydia Fein, Fabio Ferrari, Amani Sampson, Mia Charifosn, Matthew B. Schabath. Medical students' knowledge and comfort in participating in cancer prevention for LGBTQ+ patients [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-063.

OUP accepted manuscript

Background

Gynecologic cancers standard treatment often requires the removal of some reproductive organs, making fertility preservation a complex challenge. Despite heightened oncofertility awareness, knowledge about fertility attitudes and decisions of young patients with gynecologic cancer is scarce. The aim of this systematic review was to highlight what is currently known about knowledge, attitudes, and decisions about fertility, fertility preservation, and parenthood among these patients.

Methods

Peer-reviewed journals published in English were searched in PubMed, Web of Science and EMBASE from January 1, 2000 to July 1, 2020. Childbearing, fertility, fertility preservation, pregnancy, and parenthood attitudes/decisions after gynecologic cancer from women’s perspective were evaluated.

Results

A total of 13 studies comprised the review. Most of the women valued fertility preservation procedures that could be regarded as a means to restore fertility. A unique feature identified was that fertility preservation was seen also as a way to restore gender identity perceived to be lost or threatened during diagnosis and treatment. Fertility counseling was suboptimal, with wide variability among studies reviewed. Comparisons between gynecologic cancers and other cancer types about fertility counseling rates were inconclusive. The potential negative impact of impaired fertility on patients’ mental health and quality of life was also documented.

Conclusions

Fertility and parenthood were important matters in patients’ lives, with the majority of patients expressing positive attitudes toward future childbearing. Results confirm that the inclusion of patients with gynecologic cancer in research studies focusing on this topic still remains low. Additionally, the provision of fertility counseling and referral by health professionals is still suboptimal.

Organic vs Stimulant-Induced Psychosis in the Peripartum Period

This is the case of a 30-year-old pregnant female who presented to the medical emergency department with signs and symptoms consistent with a psychotic episode. At the time of presentation, the patient was noted to have paranoia and delusions focused on her current pregnancy. On further evaluation in the emergency department, the patient’s urine toxicology was found to be positive for methamphetamines. Following medical clearance, the patient was admitted for acute inpatient psychiatric stabilization. During hospitalization, her psychosis rapidly resolved with only the use of two emergency treatment injections containing antipsychotic medication. This case presents an interesting differential diagnosis between a brief psychotic disorder with peripartum onset and a substance-induced psychosis, and allows for further discussion in the differentiation and clinical treatment of these diagnoses. 

Contraception: the Need for Expansion of Counsel in Adolescent and Young Adult (AYA) Cancer Care

Little is known about oncology provider recommendations regarding best practices in contraception use during cancer treatment and through survivorship for adolescent and young adult (AYA) cancer patients. This review examined the literature to identify related studies on contraception recommendations, counseling discussions, and methods of contraception in the AYA oncology population. A literature review was conducted using PubMed, including all peer-reviewed journals with no publication date exclusions. A systematic review of the literature was conducted using combinations of the following phrases or keywords: "oncology OR cancer" AND "contraception, family planning, contraceptive devices, contraceptive agents, intrauterine devices OR IUD, vaccines, spermatocidal agents, postcoital, immunologic, family planning, vasectomy, tubal ligation, sterilization" AND "young adult OR adolescent" AND "young adult AND adolescent". Reviewers assessed articles using the "Quality Assessment Tool for Quantitative Studies" which considers: (1) selection bias; (2) study design; (3) confounders; (4) blinding; (5) data collection methods; and (6) withdrawals and dropouts. A total of five articles were included and all studies were quantitative. Results showed no consistent recommendations among providers, references to guidelines, or methods of contraceptive types. Provider guidelines for discussions with AYA patients should be expanded to provide comprehensive, consistent, and quality cancer care in the AYA population.

Patient Perspectives on Deep Brain Stimulation Clinical Research in Early Stage Parkinson's Disease

The FDA has approved a multicenter, double-blind, Phase III, pivotal trial testing deep brain stimulation (DBS) in 280 people with very early stage Parkinson's disease (PD; IDE#G050016). In partnership with The Michael J. Fox Foundation for Parkinson's Research, we conducted a survey to investigate motivating factors, barriers, and gender differences among potentially eligible patients for participation in a trial testing DBS in early PD compared to standard medical treatment. The majority of survey respondents (72%) indicated they would consider learning more about participating. Early PD patients are therefore likely to consider enrolling in trials of invasive therapies that may slow symptom progression and help future patients.

Abstract A59: Providing care for LGBTQ individuals with cancer: A call for education and training

Background: Lesbian, gay, bisexual, transsexual/transgender, and queer/questioning (LGBTQ) individuals comprise a minority and underserved group with unique and often-unrecognized health needs. The LGBTQ community faces barriers to healthcare such as problems accessing health insurance coverage and stigmatization by some healthcare providers based on sexual orientation or gender identity. Additionally, the LGBTQ community has increased cancer risks due to lower screening rates, less use of regular health care, and an elevated prevalence of cancer risk factors, compared with heterosexual and gender-aligned populations. A recent review by Quinn et al. noted that anal, breast, cervical, colorectal, endometrial, lung, and prostate cancers may disproportionally affect the LGBTQ population. The goal of this project was to identify the attitudes, knowledge, and practice behaviors of healthcare providers specializing in these seven cancer types.

Methods: A 33-item web-based survey was sent by e-mail to oncology healthcare providers at a National Cancer Institute-Designated Comprehensive Cancer Center. The survey included five sections: demographics, attitudes, knowledge, practice behaviors, and open comments. Summary responses were examined only for providers who identified as specialists in breast, gastrointestinal (GI), genitourinary (GU), gynecologic (GYN), and thoracic cancers.

Results: Of the 108 oncology healthcare providers who completed the survey, 36 (33.3%) identified as specialists in breast, GI, GU, GYN, and thoracic cancers. Among this subgroup of clinicians, almost all (91.7%) stated they were comfortable treating LGBTQ patients and agreed the LGBTQ population has unique health risks and needs. However, less than half (49.5%) correctly answered knowledge questions related to health behaviors and cancer risks of LGBTQ individuals. As for practice behaviors, 33.3% actively inquire about a patient's sexual orientation when taking a history, 38.9% agree it is important to know their patients' sexual orientation to provide the best care, and 27.8% believe they are well-informed on the health needs of LGBTQ patients. Nearly 80% believe there should be more education in health professional schools on LGBTQ health needs and 41.7% agree there should be mandatory educational events in the workplace on these needs. Open-ended comments indicated that oncologists in the five highlighted specialties lack awareness of unique LGBTQ health concerns: for example, one thoracic oncology specialist stated that because he treats lung cancer patients, he was “not sure these questions are relevant to my specific area of focus.”

Conclusions: Survey results indicate that oncology providers in specialties where LGBTQ patients may be disproportionately affected are accepting of LGBTQ individuals and acknowledge the existence of unique needs for this population, yet are largely unaware of specific health behaviors and risk factors of, and best practices regarding, this population. This study also highlights the potential need for improved LGBTQ-related content in health professional school curricula, as well as for continuing education and training for providers that addresses the care of LGBTQ patient populations.

Citation Format: Christina Tamargo, Julian A. Sanchez, Steven K. Sutton, Peter A. Kanetsky, Vani N. Simmons, Susan T. Vadaparampil, Matthew B. Schabath, Gwendolyn P. Quinn. Providing care for LGBTQ individuals with cancer: A call for education and training. [abstract]. In: Proceedings of the Eighth AACR Conference on The Science of Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; Nov 13-16, 2015; Atlanta, GA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2016;25(3 Suppl):Abstract nr A59.

Oncofertility in adolescent and young adult hereditary cancer: Considerations for genetics professionals

Adolescents and young adults (AYA) with a cancer diagnosis or those at risk for cancer due to hereditary cancer syndromes may benefit from genetic counseling and testing not only to manage personal risk but also to address reproductive concerns, especially fertility. The opportunity for genetic counselors to provide important risk information is relevant to both the newly diagnosed as well as to unaffected carriers and survivors. However, genetic counselors may need additional training in reproductive options related to AYA cancer to provide this valuable counsel. This commentary uses hereditary breast and ovarian cancer syndrome as a model to highlight important considerations when discussing preimplanatation genetic diagnosis and prenatal diagnosis, particularly in the context of expanded testing for hereditary cancer risk including multigene panels or whole exome or whole genome sequencing. Other hereditary cancers are also addressed; however, less is known about the psychosocial and fertility concerns in these AYA populations. Additionally, we provide an overview of the concept of “oncofertility” - the linkage between cancer care and reproductive medicine that aims to expand the reproductive opportunities of cancer patients - and offer support for the expansion of guidelines to include genetic counselors in AYA cancer patients’ treatment planning related to reproductive health and fertility.

14 MORPHOLOGICAL AND FUNCTIONAL PARAMETERS OF ENDANGERED BERMEYA GOAT BREED SEMEN

The Bermeya goats are an endangered autochthonous breed distributed in the north of Spain. To ensure their genetic diversity and long-term survival, morphological and functional parameters of the semen must be known in order to preserve the current genetic stock in a germplasm bank. The aim of this work was to establish basic characteristics and post-thaw survival of Bermeya goat's semen obtained by electro-ejaculation, that is not well described in the literature. The semen was collected by electro-ejaculation from 7 bucks, 1 to 7 years old, twice per week, for 9 weeks (n = 83). Fresh semen was evaluated for volume (V), concentration (C), motility, morphology, functional integrity of the sperm (spz) membranes (hypoosmotic swelling test; HOST), and acrosome integrity rate (NAR). Individual and progressive sperm motility were analyzed by means of a computer-assisted sperm analysis system (CASA: SCA 2002�, Microptic, Barcelona, Spain) immediately after dilution with the extender at 37�C, and after cooling to 4�C; five fields per sample (diluted to 204 � 106 spz mL–1) were evaluated under a phase contrast microscope (100�). The NAR and morphological abnormalities of sperm head, midpiece, tail, and cytoplasmic droplets were determined by counting 100 spz under 1000�. For freezing, ejaculates with at least 80% motile spz were diluted at 32�C with Krebs-Ringer solution containing 20% egg yolk and 14% glycerol to a final concentration of 400 � 106 spz mL–1, cooled to 4�C for 90 min, aspirated into 0.25-mL plastic straws (IMV�, L'Aigle, France), frozen at 7 cm above liquid nitrogen (LN2) phase for 10 min, and then plunged into the LN2. Straws were thawed in a water bath at 39�C for 30 s for post-thaw survival analysis. Data were analyzed by the GLM and FREQ procedures (SAS; SAS Institute, Inc., Cary, NC, USA) and expressed as means � standard error. Fresh semen characteristics were: V = 1.7 � 0.1 mL; C = 2619 � 106 � 153 spz mL–1; total and progressive motility were 89.0 � 2.1% and 66.9 � 2.1%, respectively. Percentages of head abnormalities were 4.8 � 0.5; midpiece: 3.8 � 0.7; tail: 4.7 � 1.0; cytoplasmic droplets: 8.3 � 0.7; intact acrosome: 91.8 � 0.6; and membrane integrity: 49.2 � 2.1. At 4�C, the % of total motile spz was 62.6 � 1.6, and the post-thaw survival rate was 46.3 � 1.5. There were only individual differences (P < 0.001) between bucks on sperm concentration, head abnormalities, and cytoplasmic droplets. In conclusion, our results indicate that semen quality is related to each individual animal and that electro-ejaculation allows collection of semen of satisfactory quality to use as fresh and for cryopreservation. However, the validity of our results for possible future sperm banking of endangered Bermeya goats semen must be confirmed by field trials.

Experimental neosporosis in bulls: Parasite detection in semen and blood and specific antibody and interferon-gamma responses

AIM

To investigate the presence of Neospora caninum in semen and blood, and the development of specific antibody and interferon-gamma (IFN-gamma) responses in experimentally infected bulls.

METHODS

Eight bulls were intravenously infected with 10(8) live N. caninum tachyzoites of NC-1 isolate. The presence of N. caninum in semen and blood was assessed using a nested-PCR procedure. PCR-positive semen samples were bioassayed using a BALB/c nu/nu mouse model. Specific anti-N. caninum antibody and IFN-gamma responses were also examined. In parallel, eight seronegative bulls were studied as non-infected controls. All bulls were monitored for 26 weeks.

RESULTS

All eight experimentally infected bulls showed N. caninum DNA in their semen and/or blood samples at some time during the course of the study. Parasite load in semen ranged from 0.1 to 14.5 parasites/ml (mean 6.0). N. caninum could not be detected in BALB/c nu/nu mice inoculated with PCR-positive semen samples. A significant increase in mean serum specific IgM antibody response to N. caninum was detected between 10 and 28 days post-infection (p.i.). Serum specific IgG, IgG1, and IgG2 antibody levels in experimentally infected bulls were significantly different after 21, 10, and 14 days p.i. as compared to controls, respectively. Specific anti-N. caninum IgG were detected in seminal plasma from infected bulls and values obtained were different from controls after 25 days p.i. Mean specific IFN-gamma responses in experimentally infected bulls were significantly higher than controls 3 days p.i.

CONCLUSIONS

This is the first study to report the presence of N. caninum DNA in the semen and blood of experimentally infected bulls. Our observations indicate an intermittent presence of N. caninum in low numbers in semen and associated with chronic stage of the infection. This study is also the first to report the detection of anti-N. caninum IgG in seminal plasma of experimentally infected bulls.

20 SPERM CHARACTERIZATION OF ASTURCON PONIES AFTER COLLECTION AND EQUILIBRATION/REFRIGERATION BEFORE FREEZING

The need to conserve farm animal biodiversity is accepted by many countries through the ratification of the convention of biological diversity, and sperm quality is known to be an important criterion in the evaluation of breeding soundness. The aim of this work was to characterize the semen of a local breed of ponies 'Asturcon' (maintained free over the mountains all year around) before its incorporation into a germplasm bank. Semen was obtained from six stallions (6–17 years of age) using an artificial vagina, 3 days/week, during 12 weeks. Immediately after collection, gel-free semen was evaluated for volume, sperm concentration, and motility. Semen motility was again evaluated after equilibration/refrigeration. For evaluation of individual (IM) and progressive motility (PM) rates, semen was diluted (20 � 106 spermatozoa/mL) and analyzed with a CASA System (SCA; Microptic S.L., Barcelona, Spain). Five fields per sample were evaluated (minimum 500 spermatozoa/sample) under a phase contrast microscope (100�). Semen samples were subjected to a hypo-osmotic swelling test (HOS) test to detect the presence of swollen tails in a 100 mM citrate–fructose solution. Percentages of altered acrosomes and morphological abnormalities were determined by counting 100 spermatozoa (1000�). Then, semen was diluted and centrifuged for 10 min at 600g. After the supernatant was discarded, the pellet was re-suspended in freezing medium (skim milk extender containing 2% egg yolk and 2.5% glycerol) to a final concentration of 100 � 106 spermatozoa/mL, and equilibrated/cooled (60 min) to 4�C. Statistical analysis was carried out by means of the GLM and CORR procedures and Duncan test for means (SAS Institute, Inc., Cary, NC, USA). A significant effect between males (P &lt; 0.05) on semen quality, such as volume of the ejaculate, sperm concentration, and morphological abnormalities, were detected among stallions. On the other hand, positive and significant correlations were found between the sperm motility immediately after collection and after equilbration/refrigeration (r = 0.73; P &lt; 0.05); moreover, sperm motilities (both fresh and refrigerated) correlated with the results of the HOS test (r = 0.56; P &lt; 0.001, and r = 0.27, P &lt; 0.05, respectively). These preliminary results confirm that the sperm of the Asturcon ponies breed can be collected and will survive the equilibration/refrigeration procedures. Conservation and development of local breeds is important because they represent a unique source of genes for improving health and performance traits of industrial breeds. However, complementary studies on the ability of the stallion sperm to survive freezing/thawing procedures in rates higher than 30% are needed to ensure that genetic banks are correctly created. This work was performed in collaboration with ACPRA and Dep�sito de Sementales de Santander (Spain), and supported by RZ2004-00031-C02-01.

111 ESTIMATION OF SPERM QUALITY IN FRESH AND FROZEN - THAWED SEMEN FROM ASTURIANA DE LOS VALLES BULLS

Artificial insemination and semen cryopreservation have significantly improved the breeding potential of male animals. However, current freezing techniques commonly result in reduced semen quality (Januskauskas et al. 1999 Theriogenology 52, 641-658), and surviving cells are affected post-thaw either structurally or functionally (Nagy et al. 2004 Anim. Reprod. Sci. 80, 225-235). In this work we analyze the impact of cryopreservation on Asturiana de los Valles bull sperm. Ejaculates (n = 373) from seven adult bulls were weekly collected by means of artificial vagina. Immediately after collection, routine parameters including volume (V), mass motility (MM), and concentration (C) of sperm cells were evaluated. Then the semen was extended with a commercial extender, loaded into 0.25-mL plastic straws at a concentration of 23 � 106 per straw, frozen and stored for further analysis. Four straws per ejaculate were thawed, pooled and analyzed for motion characteristics by means of a CASA system (Sperm Class Analyzer, SCA 2002� Microptic S. L., Barcelona, Spain) added to an optical phase-contrast microscope with heatable (37�C) stage. Immediately after thawing, we analyzed the % of motile spermatozoa (MS) and the % of progressively motile spermatozoa (PMS); then samples were incubated for 3 h at 37�C and MS and PMS were measured again (MS3 and PMS3, respectively). Functional integrity of the plasmallema was evaluated by the hypoosmotic swelling test (HOST) together with the % of typical tail coiling/swelling (percentage of HOST-positive spermatozoa, HOST-PS). The % of viable spermatozoa (VS) [membrane integrity was evaluated by fluorescence microscopy with a dual staining system (propidium iodide (PI) and 6-carboxyfluorescein diacetate (CFDA)]. Sperm showing partial or complete red fluorescence (PI staining) were considered nonviable, whereas sperm showing complete green fluorescence were considered viable. Altered acrosomes (AA) and morphological abnormalities were also determined. The % of morphological abnormalities was classified according to their location in head (HA), midpiece (MA), and tail (TA). Proximal and distal cytoplasmic droplets were counted as separate abnormalities (CD). Data were analyzed by the MEANS procedure of SAS (SAS Institute, Inc., Cary, NC, USA). A significant (P < 0.05) decrease in the sperm motility was observed after freezing/thawing (MS: 80.20 � 0.75 vs. 47.36 � 1.04, and PMS: 68.73 � 0.73 vs. 42.14 � 0.96 for fresh and frozen-thawed semen, respectively). Also, the frozen-thawed sperm showed increased % of HA, MA, AA, HOST-PS, and VS (P < 0.05). These morphological abnormalities could contribute to decreasing sperm motility. The new computer and video technologies provide useful information about sperm quality and can be used in the daily routine of processing semen. This work was performed in collaboration with ASEAVA.