Influence of Griseofulvin treatment on semen quality in the dog

Griseofulvin is used to treat dermatomycosis in many species and causes oligospermia in supra-pharmacological doses. The aim of the present study was to evaluate the effect of Griseofulvin administered at therapeutic doses upon semen quality in dogs. Four dogs were treated with Griseofulvin (25 mg/kg per day) for 30 days. Semen collections and analyses were performed before, during and for 100 days after treatment for the Griseofulvin group and 10 untreated control dogs. Semen analyses included mean percentage of forward progressively motile sperm, total sperm output, normal live sperm and normal dead sperm. There was no significant difference between control and treated dogs for each of the semen quality parameters. Therapeutic dosage of Griseofulvin had no deleterious effect upon semen quality in dogs, although this does not preclude potential embryotoxic and teratogenic effects.     

Semen evaluation in the chamois of Abruzzi (Rupicapra pyrenaica ornata)

The chamois of Abruzzi (Rupicapra pyrenaica ornata) has been classified as endangered by the World Union for Conservation. The objective of this study was to analyze seasonal differences in the characteristics of various male reproductive organs and in semen quality. The study was conduced during 2004 in the reserve of Lama dei Peligni (Italy) on three chamois males aged between 2 and 5 years. Males were captured during March-May months and October-December months. Various testicular and scrotal measurements were taken and semen was collected using an electroejaculator. Sperm motility pattern was evaluated using computer assisted sperm analyzer, membrane integrity using differential staining and morphology with phase contrast microscopy. Testicular size, sperm motility membrane integrity and the percent of morphological normal spermatozoa were greater during October-December. The authors concluded that sperm characteristics are strongly influenced by season and that semen collected in this period (breeding season) has suitable quality for manipulation and long-term preservation.     

Effect of season on fertility of frozen buffalo semen

Twenty double ejaculates from each of ten water-buffalo bulls were collected in June (non-breeding season) and again in November (breeding season). Fresh semen was screened for sperm quantity, motility, eosin uptake, and sperm morphology and was frozen using lactose, skim-milk, and Tris extenders. Thawed semen was checked for motility and Sephadex filtration. Half of each semen batch was used for artificial insemination in the breeding season and the other half during the non-breeding season.Laboratory screening revealed that June semen had a significantly lower Sephadex filtration rate and a higher percentage of abnormal sperm cells, and three June ejaculates were excluded from further processing due to poor sperm motility. In the remaining ejaculates the motility before freezing and the sperm cell quantity were higher in June semen than in November semen. Eosin uptake, mass motility, and post-freeze-motility did not vary with season. November semen produced significantly higher pregnancy rates than June semen over a total of 3220 inseminations in both seasons. Forty percent of the observed seasonality of buffalo fertility was attributable to the male. No fertility differences appeared between extenders used. When November semen was used, the fertility in adult buffaloes in both seasons was higher than in heifers.     

Semen characteristics of the guinea fowl Numida meleagris meleagris

Eighteen adult exotic Golden Sovereign guinea fowl (Numida meleagris meleagris) males identified by leg bands and housed individually in cages were ejaculated two times a week at 4- and 3-d intervals (Mondays and Thursdays) for 6 wk. Semen was obtained manually by gently massaging the dorso-lateral lumbo-sacral region. Semen collection and evaluation were done between 1400 and 1800 h each day of test. Mean semen volume was 0.032 +/- 0.001 ml, sperm motility was 37.1 +/- 0.1% and sperm concentration/ml was 2.62 +/- 0.01 x 10(9). Percentage live sperm averaged 91.6 +/- 0.1, while the mean percentage morphologically normal spermatozoa was 76.9 +/- 0.5. Primary and secondary sperm abnormalities were 11.9 +/- 0.2% and 11.3 +/- 0.2%, respectively. Birds differed significantly in all ejaculate characteristics studied except percent secondary abnormalities, indicating that considerable variation exists for improvement of these semen traits. There were significant bird x collection interval (P<0.05) and bird x week (P<0.01) interactions for sperm concentration/ml and bird x week interaction for sperm motility (P<0.05). The results generally are within acceptable levels and show that the semen is suitable for use in artificial insemination.     

Characterization of semen collected from beagles and captive Japanese black bears (Ursus thibetanus japonicus)

This study characterized semen collected from the Japanese black bear, Ursus thibetanus aponicus, to provide information on semen cryopreservation for artificial breeding. Preliminary studies using a beagle dog as the model species showed that sperm concentration and total sperm count were lower in semen collected by electroejaculation than in semen collected by digital manipulation, but that sperm motility, viability and morphology were similar. Characterization of semen obtained from Japanese black bears by electroejaculation under general anesthesia revealed that semen volume and total number of spermatozoa collected were lower; but that sperm concentration, motility, viability and morphology were equivalent to those reported in other ursids. When semen was collected via a catheter inserted into the urethra during the stimulation for ejaculation, the sperm concentration, total sperm count and motility were relatively higher than when semen was collected directly in a test tube. Specific normal semen characteristics (mean +/- SEM) were pH, 7.6 +/- 0.0; volume, 0.212 +/- 0.038 mL; sperm concentration, 361 +/- 100 x 10(6)/mL; total sperm count, 84.0 +/- 32.2 x 106; +++ motility, 30 +/- 5%; motility, 77 +/- 3%; viability 77 +/- 2%; and abnormal morphology, 11+/- 2%. These results suggest that semen can be collected from Japanese black bears by electroejaculation.     

Genetic and phenotypic parameter estimates for scrotal circumference and semen traits in young beef bulls

Estimated in this study were heritabilities and genetic and phenotypic correlations involving scrotal circumference (SC), percent live sperm, sperm number, sperm concentration, sperm motility, and an overall measure of a bull's potential breeding efficiency. Potential breeding efficiency is a composite trait based on a consideration of sperm concentration, sperm motility, sperm morphology and scrotal circumference. Data used were from three sources. Records on 863 Angus, 753 Polled Hereford, and 302 Simmental bulls were made available through the Missouri Performance-Tested Bull Sale and records on 1169 Polled Hereford bulls came from the American Polled Hereford Association. Information from these first two data sets were used to estimate heritability of scrotal circumference. The third data set was provided by Nichols Farms of Bridgewater, Iowa, and included information from the records of 465 yearling Polled Hereford and 264 yearling Simmental bulls. This latter data set was used to estimate all of the above mentioned parameters. Each data set was kept separately for the purpose of statistical analysis. Parameters were estimated using components from paternal half-sib analysis of variance and covariance. Pooled estimates of heritability for SC, sperm concentration, sperm motility, percent live sperm, sperm number and potential breeding efficiency were 0.51 +/- 0.09, 0.20 +/- 0.13, 0.11 +/- 0.12, 0.00, 0.19 +/- 0.14 and 0.13 +/- 0.12, respectively. Phenotypic correlations involving the six traits were very consistent for the two breeds. Combined across breeds their values ranged from 0.47 for SC and percent live sperm to 0.96 for sperm concentration and potential breeding efficiency. Corresponding genetic correlations were generally positive and high and ranged from 0.65 for SC and sperm motility to 1.14 for sperm number and potential breeding efficiency.     

Trehalose enhanced the freezability of Poodle dog sperm collected by an artificial vagina (AV)

In an attempt to develop a suitable freezing method for Poodle dog sperm, an experiment was conducted to investigate semen collection methods of digital stimulation and an artificial vagina (AV), using Tris and trehalose-egg yolk extender, on the characteristics and cryopreservation of sperm. Two dogs (dogs A and B) were subjected to semen collection by digital stimulation and AV. The volume, sperm concentration, sperm motility index (SMI) and acrosome status of ejaculates were determined immediately after collection. The remainder was frozen as pellets in Tris and trehalose-egg yolk extender. Sperm motility index was evaluated after thawing and during a thermal resistance test, and acrosome integrity was also assessed. No significant differences regarding sperm concentrations, SMI and acrosome integrity were observed between semen collected by AV and digital stimulation. However, when dog sperm were collected by an AV and frozen in trehalose-egg yolk extender, the motility index of frozen-thawed sperm was significantly improved compared to sperm frozen in Tris-egg yolk extender which were collected by digital stimulation. In conclusion, semen collected by an AV and frozen in trehalose-egg yolk extender was effective in enhancing the freezability of Poodle dog sperm.     

Identification of a premature stop codon in the melanocyte-stimulating hormone receptor gene (MC1R) in Labrador and Golden retrievers with yellow coat colour

We have examined whether black/yellow coat colour in Labrador retrievers is controlled by allelic variants at the extension locus. As the gene encoding the melanocyte-stimulating hormone receptor (MC1R) has been shown to correspond to the extension locus in several species, we have determined the genomic MC1R sequence in Labrador retrievers with black and with yellow coat colour. Using primers based on the fox (Vulpes vulpes) MC1R sequence we initially isolated and sequenced the innerpart of the canine MC1R. By means of inverse PCR we succeeded in the characterization of both flanking regions of the MC1R gene (Genbank: AF064455). Comparison of the complete MC1R sequences of a yellow and a black Labrador retriever revealed a single C-->T mutation at nucleotide position 916 in the yellow dog. This transition changed the codon for arginine at position 305 into a stop codon, resulting in the elimination of the evolutionary strongly conserved 10 carboxyterminal amino acid residues. With an allele-specific-oligonucleotide (ASO) test it was shown that the mutation cosegregated with the recessively inherited yellow coat colour in the Labrador retriever. Golden retrievers also appeared to be homozygous for the mutation. Seventeen other breeds were all negative for the mutation. Since the Labrador and Golden retriever are closely related, we suggest a common founder for the yellow coat colour in Labrador and Golden retrievers.     

Semen collection,cryopreservation and artificial insemination in the dromedary camel

Collection of semen with a bovine artificial vagina (AV) was attempted with each of 14 camels over a period of 2 years. Semen samples were evaluated, extended and cryopreserved. Frozen thawed semen, diluted cooled semen or whole semen was used to inseminate some female camels which were induced to ovulate with hCG. Males ejaculated semen into the AV in 74.6% collection attempts. The male copulated for at least 200s in 62.9% attempts. The remaining copulations were of shorter duration. Similarly, 49.3% ejaculates were at least 3ml of semen. Libido and donation of semen improved from December onwards and reached a peak after mid January with peak performance persisting until April. It declined during May. The majority of camels had lost libido and refuse to donate semen by the end of May. Camel semen is in gel form. While 35.9% of 203 semen samples exhibited no individual sperm motility, 28.5% exhibited low to fair grade individual sperm motility and only 35.4% exhibited >50% sperm motility. Differences existed between animals (P<0.01) and months (P<0.05) of collection, while effect of copulation time was not significant. Mass motility was not observed in camel semen. Individual sperm motility develops after liquefaction of semen. Addition of caffeine but not chymotrypsin improved the individual motility. The mean live percent sperm count and normal acrosome were 73.3+/-1.0 and 92.0+/-0.5, respectively. Only 51.1% of 45 semen samples with pre-freeze motility of >50% and 25% of 16 semen samples from low pre-freeze motility group with an overall success of 44.2% of 61 semen samples were successfully preserved. Wide variation was observed in the freezability of semen from different males. Attempts to impregnate female camels with liquid semen, frozen thawed semen and whole semen after hCG induced ovulation resulted in 0/10, 1/13 and 4/10 pregnancies.     

Simple and Effective Methods of Freezing Capercaillie (Tetrao urogallus L.) Semen

A continuous decline in the number and range of capercaillie (Tetrao urogallus L.) in many European countries can be observed, mostly due to habitat destruction by human activity, unecological forestry management, and increased density of natural predators. Ex situ in vitro gene banks provide a unique opportunity to preserve the genetic material for future generations. Simple and effective cryopreservation methods for capercaillie semen are discussed. Semen was collected from seven males kept in the Capercaillie Breeding Centre at Forestry Wisła in Poland. Within five minutes after collection, ejaculates were diluted with EK diluent, then divided into two parts, and subjected to two freezing procedures: in pellets and in straws. In fresh semen, ejaculate clearness, viscosity, color and volume, as well as sperm concentration, motility and morphology, were evaluated, while in frozen-thawed semen only motility and morphology of sperm were determined. Fertilizing ability of thawed semen was examined for samples frozen in straws. Significant (P<0.05) differences between individual males were found in relation to the majority of fresh semen traits: ejaculate volume averaged 102.1 µL (varying from 49.0 to 205.0); average sperm concentration was 632.5 x10⁶ mL^-1 (178.8–1257.1); percentage of live normal cells varied from 39.2 to 70.3% (58.7% on an average); percentage of motile cells ranged from 76.0 to 85.7%) and motility parameters were male dependent, as well. Both cryopreservation methods had a negative effect on morphology and motility of frozen-thawed semen; however, the straw method yielded 60.7% and the pellet method 42.5% of live cells in total in thawed semen (P<0.05), while the number of live normal (intact) cells was similar (22.4 and 22.2%, respectively). Egg fertility varied between 77.8 and 91.7% (average 84.4%). Both freezing procedures seem to be effective in obtaining acceptable viability and high fertilizing potency of thawed sperm and can be used to create a gene bank of capercaillie semen.     

The efficacy of ultrasound treatment as a reversible male contraceptive in the rhesus monkey

ABSTRACT: BACKGROUND: The use of therapeutic ultrasound as a contraceptive approach has involved nonhuman primates as well as rats and dogs. The current study was undertaken to determine whether this treatment could be a method for reversible contraception, using a model with testes size similar to adult humans. METHODS: Two methods of ultrasound exposure were used, either the transducer probe at the bottom of a cup filled with saline (Cup) or direct application to the surface of the scrotum (Direct). Four adult rhesus (Macaca mulatta) males with normal semen parameters were treated with therapeutic ultrasound at 2.5 W/cm(2) for 30 min. Treatment was given 3 times, one every other day on a Monday-Wednesday-Friday schedule. For each male, semen quality was evaluated a minimum of three times over several months prior to ultrasound exposure and weekly for two months following ultrasound treatment. RESULTS: Semen samples from all males, regardless of exposure method, exhibited a decrease in the percentage of motile sperm following ultrasound treatment. There was an average reduction in motility of 40% the week following treatment. Similarly, curvilinear velocity and the percentage of sperm with a normally shaped flagellum were also reduced in all males following ultrasound treatment. A significant reduction in the total number of sperm in an ejaculate (total sperm count) was only observed in males that received ultrasound via the cup method. Following treatment via the cup method, males exhibited up to a 91.7% decrease in average total sperm count (n = 2). Sperm count did not approach pre-treatment levels until 8 weeks following ultrasound exposure. CONCLUSIONS: The sustained reduction in sperm count, percent motility, normal morphology, and sperm vigor with the cup exposure method provides proof of principle that testicular treatment with ultrasound can be an effective contraceptive approach in humans.     

Anti-sperm antibodies and seminal characteristics after testicular biopsy or epididymal aspiration in dogs

A study was performed to determine if performing testicular biopsies or epididymal aspirates in dogs would induce sperm-bound anti-sperm antibodies (ASA), affect long-term sperm production or semen quality. Semen was collected from 8 mature dogs 3 times a week before and after hemicastration and then 3 times a week after testicular biopsy (n=3 and 1 control) or epididymal aspiration (n=3 and 1 control). Detection of anti-sperm IgG (ASA) on sperm cells was performed by flow cytometry analysis using a flow cytometer. Two dogs with testicular biopsies became positive for ASA 16 d after testicular biopsy and remained positive for 7 and 9 d, respectively. One dog that had an epididymal aspirate became positive 13 d after epididymal aspiration and remained positive for 35 d. One dog became positive 21 d after hemicastration and remained positive for 28 d. Sperm output declined significantly in 7 of 8 dogs after hemicastration. A control epididymal aspirate treatment dog had decreased sperm output, and a testicular biopsy treatment dog had increased sperm output. None of the dogs with ASA had significant changes in sperm output after treatment. Sperm motility declined significantly in 3 dogs after hemicastration. An epididymal aspiration treatment dog had a decrease in sperm motility, a control epididymal aspirate treatment dog and a control testicular biopsy treatment dog each had increases in sperm motility. None of the dogs with ASA had significant changes in motility. The percentage of normal spermatozoa significantly decreased in 3 dogs and significantly increased in 1 dog after hemicastration. Two dogs that had testicular biopsies and 1 dog that had an epididymal aspiration had decreases in percent normal sperm. Two of 3 dogs with decreases in percent normal sperm after treatment had ASA, but 2 dogs with ASA had no change in motility. Hemicastration, epididymal aspiration, and testicular biopsy can induce ASA production within 2 wk of the procedure, but ASA are transient and do not have a predictably negative effect on total sperm output or motility. Testicular biopsy and epididymal aspiration are safe diagnostic procedures, but further work investigating post-treatment fertility must be done before final conclusions can be made.     

Morphometry of normal and teratozoospermic canine sperm heads using an image analyzer: work in progress

Combining the traditional morphologic evaluation of spermatozoa with computer assisted image analysis adds randomness, objectivity, repeatability and accuracy to morphometric measurements. We collected semen from 10 fertile, normospermic dogs aged 1 to 7 yr and from 3 teratozoospermic breed-matched dogs. Sperm head morphology was examined in Giemsa-stained smears by light microscopy, using a computer-assisted image analyzer and by transmission electron microscopy. We found significant variation in sperm head area, length, width and degree of roundness among normospermic individual dogs, indicating that it would be necessary to examine many more dogs before the size and shape of normal dog spermatozoa could be determined. The normospermic dogs were used as controls for the teratozoospermic cases. Case 1: A 2-yr-old subfertile Cavalier King Charles Spaniel had semen with small and narrow-based sperm heads and a proximal cytoplasmic droplet in most of the spermatozoa. With the image analysis system, sperm heads were shown to be smaller and more oval than in normospermic dogs. The variatons in size and shape were similar in magnitude to those of control dogs. An examined infertile half-brother had similar semen quality. Case 2: A 3-yr-old Petit Basset Griffon Vendeen with 2 unsuccesfull matings exhibited spermatozoa with severe abnormalities. Measured by image analyzer, sperm heads were irregular in shape and very small in area. One of the two littermates examined had semen of the same quality as the case dog. Case 3: A 3-yr-old fertile Golden Retriever had semen with giant sperm heads in about 50% of spermatozoa. Image analyzing results revealed 2 populations of different sized sperm heads. Giant heads consisted of 52.2% of all spermatozoa. The results of the study reported here suggest that the image analysis technique may be useful in evaluating structural changes in sperm morphology, supplementing visual assessment that is used in conventional methods.     

Seasonal variation in serum testosterone, testicular volume and semen characteristics in coatis (Nasua nasua)

The objective was to characterize seasonal changes in serum testosterone concentration, testicular volume and sperm quantity and quality in captive coatis (Nasua nasua) from Pantanal, MT, Brazil. Sampling was done once monthly for 1 y. Mean (± SEM) serum testosterone concentrations (767.37 ± 216.2 ng/ml) and total and progressive sperm motility (79.6 ± 3.9%; 3.8 ± 0.3, on a scale of 0 to 5) peaked in July. The highest combined testis volume (10.3 ± 0.4 cm³) and sperm concentration (403 million ± 102 sperm/ml) occurred in August, at the peak of the winter breeding season. No seasonal effects on percentages of morphologically normal sperm, acrosome integrity, or live sperm were detected; however, the percentage of secondary sperm defects was higher in the winter. In conclusion, intricate relationships between testosterone concentration, testis volume, semen concentration and total and progressive sperm motility with high levels of breeding activity were observed during the dry season in the winter (June, July, August), followed by a subsequent decline in these activities during the wet season (i.e., summer: December, January, February). There was no seasonal pattern for production of functionally intact and morphologically normal sperm.     

Semen quality in dogs and the influence of a short-interval second ejaculation

Semen quality was examined in each of 65 known fertile dogs. Values were found to be similar to those previously published, although an apparent breed influence was demonstrated, with German shepherd dogs producing ejaculates of larger volume and greater total spermatozoal output than other breeds. A second ejaculate was collected from each dog with a mean interval of 63 min. The second samples had significantly lower values for the volume of the second fraction, the spermatozoal concentration and the total spermatozoal output. There were no differences for the percentage motility or the percentage of morphologically normal live spermatozoa. While there was no increase in semen quality of the second ejaculate, the technique may be useful since it results in the collection of approximately 70% more spermatozoa than a single ejaculate. These spermatozoa also had normal motility and morphology and could, therefore, be used for insemination or cryopreservation.     

Artificial insemination in canids: a useful tool in breeding and conservation

Artificial insemination (AI) and semen freezing have become services available to dog owners worldwide, and the demand for services to freeze semen is increasing. In other canids such as the fox, the fur industry utilizes fresh or frozen semen to artificially inseminate vixens to produce pelts. Clearly, AI facilitates the use of a male to sire several females by diluting the ejaculate, increases breeding hygiene, and allows crossing between species with slightly different breeding seasons. The African wild dog (Lycaon pictus) is currently considered by the World Conservation Union (IUCN) as one of most endangered canids. In captive populations of African wild dogs, semen has been frozen with encouraging results, using a standard cryopreservation protocol for domestic dogs, but successful AI has not been reported. In wolves, there is one report regarding the live birth of an offspring after intravaginal AI of a deslorelin-induced estrous female. In 2005, three Mexican gray wolf females were artificially bred by intrauterine insemination with freshly collected semen from unrelated males, and all females whelped. Artificial insemination may be vaginal, intrauterine or intratubal, and the semen may be fresh, fresh and chilled (diluted), or frozen-thawed, and the source of semen may be epididymal or ejaculated. In the domestic dog, the results are good to excellent for AI with all three types of processed semen when the source is ejaculated semen, whereas epididymal sperm still yields poorer results. Species differences in female physiology, as well as differences in the cryotolerance of the sperm from various canid species, warrant further research and development.     

Retrospective Analysis for Genetic Improvement of Hip Joints of Cohort Labrador Retrievers in the United States: 1970–2007

Background

Canine Hip Dysplasia (CHD) is a common inherited disease that affects dog wellbeing and causes a heavy financial and emotional burden to dog owners and breeders due to secondary hip osteoarthritis. The Orthopedic Foundation for Animals (OFA) initiated a program in the 1960''s to radiograph hip and elbow joints and release the OFA scores to the public for breeding dogs against CHD. Over last four decades, more than one million radiographic scores have been released.

Methodology/Principal Findings

The pedigrees in the OFA database consisted of 258,851 Labrador retrievers, the major breed scored by the OFA (25% of total records). Of these, 154,352 dogs had an OFA hip score reported between 1970 and 2007. The rest of the dogs (104,499) were the ancestors of the 154,352 dogs to link the pedigree relationships. The OFA hip score is based on a 7-point scale with the best ranked as 1 (excellent) and the worst hip dysplasia as 7. A mixed linear model was used to estimate the effects of age, sex, and test year period and to predict the breeding value for each dog. Additive genetic and residual variances were estimated using the average information restricted maximum likelihood procedure. The analysis also provided an inbreeding coefficient for each dog. The hip scores averaged 1.93 (±SD = 0.59) and the heritability was 0.21. A steady genetic improvement has accrued over the four decades. The breeding values decreased (improved) linearly. By the end of 2005, the total genetic improvement was 0.1 units, which is equivalent to 17% of the total phenotypic standard deviation.

Conclusion/Significance

A steady genetic improvement has been achieved through the selection based on the raw phenotype released by the OFA. As the heritability of the hip score was on the low end (0.21) of reported ranges, we propose that selection based on breeding values will result in more rapid genetic improvement than breeding based on phenotypic selection alone.     

Epigallocatechin-3-gallate added after thawing to frozen dog semen: Effect on sperm parameters and ability to bind to oocytes’ zona pellucida

Dog sperm cryopreservation is gaining importance both in breeding dogs for commercial purposes and for pet animals. Anyway, cryopreservation of mammalian spermatozoa, including dog ones, induces some negative effect on sperm fertility, leading to a lower use of this technique and limiting its widespread use. Therefore, studies to improve the quality of canine semen after cryopreservation could have a relevant impact on both the scientific advancement and the clinical practice. The aim of the present work was to investigate the putative ameliorative effect of Epigallochatechin-3-gallate (EGCG) addition to post thawing medium on dog sperm motility, mitochondrial activity, acrosome integrity and on zona-binding ability (zona binding assay). Spermatozoa were thawed in Tris-fructose-citrate medium supplemented with EGCG (0, 25 and 50 μM) and sperm motility, mitochondrial activity and acrosome integrity were assayed at 0.5, 1.5, 3 and 6 h after post thawing incubation at 37 °C. An aliquot of semen from each treatment group after 1.5 h post thawing incubation was washed and used to perform heterologous (using porcine oocytes) or homologous zona binding assay. The results obtained showed that no significant effect is exerted by EGCG on sperm parameters analysed neither at 0.5, 1.5, 3 or 6 h after thawing excepting for the reduction of the percentage of live cells with active mitochondria at the higher dose at 6 h; furthermore, both homologous or heterologous zona binding ability, was not influenced by EGCG. In conclusion, EGCG supplementation to thawing medium does not improve dog sperm quality or zona binding capacity.     

Quality and fertility of cooled-shipped stallion semen at the time of insemination

Stallion semen processing is far from standardized and differs substantially between AI centers. Suboptimal pregnancy rates in equine AI may primarily result from breeding with low quality semen not adequately processed for shipment. It was the aim of the study to evaluate quality and fertility of cooled-shipped equine semen provided for breeding of client mares by commercial semen collection centers in Europe. Cooled shipped semen (n = 201 doses) from 67 stallions and 36 different EU-approved semen collection centers was evaluated. At arrival, semen temperature was 9.8 ± 0.2 °C, mean sperm concentration of AI doses was 68 ± 3 x 10⁶/ml), mean total sperm count was 1.0 ± 0.1 x 10⁹, total motility averaged 83 ± 1% and morphological defects 45 ± 2%. A total of 86 mares were inseminated, overall per season-pregnancy rate in these mares was 67%. Sperm concentration significantly influenced semen motility and morphology at arrival of the shipped semen. Significant effects of month of the year on volume, sperm concentration and total sperm count of the insemination dose were found. The collection center significantly influenced all semen parameters evaluated. Semen doses used to inseminate mares that became pregnant had significantly higher total and progressive motility of spermatozoa and a significantly lower percentage of morphological semen defects than insemination doses used for mares failing to get pregnant. Results demonstrate that insemination with semen of better quality provides a higher chance to achieve pregnancy. Besides the use of stallions with good semen quality, appropriate semen processing is an important factor for satisfying results in artificial insemination with cooled-shipped horse semen.