Probable spermatozoal diploidy in the semen of a golden retriever.

The semen of a 3-year-old golden retriever was examined for breeding purposes. When the morphology of the spermatozoa was analysed for the first time, 37% were observed to have giant heads. In most of the giant heads, a diadem defect was also found. The dog was successfully used for breeding. On re-examination, the percentage of giant heads was found to be greater than before. The right testicle exhibited tissue softening. To determine the reason for the defect, an aspiration needle biopsy was performed and ultrasound examination undertaken. In the biopsy smears, both normal spermatozoa and spermatozoa with giant heads were found. On ultrasonography, the echogenicities of both testicles were the same, and normal. DNA flow cytometry was performed to determine the DNA content of the spermatozoa. Two populations of sperm cells were detected, one having a median fluorescent intensity twice as high as that of normal spermatozoa, suggesting a diploid DNA content. Transmission electron microscopy (TEM) was performed to find out whether the altered intensity correlated with the ultrastructure of the spermatozoa. The nuclei of the sperm heads showed a normal chromatin condensation. Semen quality became worse over a period of 2 years, with 60% giant heads in the last sample. The process was considered to be progressive spermatogenic degeneration with diploidy. Relatives examined did not suggest any hereditary predisposition to the problem. The male was still fertile at the time of the last sample collected and sired a litter of 10 healthy puppies.

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.

Fertility parameters in male Irish wolfhounds: a two-year follow-up study.

The reproductive performance of 25 male Irish wolfhounds was examined in a two-year follow-up study. Results of a previous study showed that 37 Irish wolfhounds had lower libidos, smaller testicles and poorer semen quality than 67 control dogs examined. This study was undertaken to determine whether fertility parameters had changed after a further two years. Forty-four dogs of 21 breeds were used as controls. No change in libido was observed in either group after two years; the Irish wolfhounds still exhibited lower libidos than the control dogs. In both studies, the Irish wolfhounds showed a softening of testicular tissue with a significantly higher incidence than control dogs. This difference became more marked after two years. Semen quality had declined in Irish wolfhounds and the differences between the two groups became more accentuated. Inbreeding coefficients for the Irish wolfhounds were low, suggesting that this was a factor contributing to the poor reproductive function. However, several Irish wolfhounds had been ill during the follow-up period which, together with the decline in reproductive efficiency, may reflect a change due to ageing.

Poor semen quality in Irish wolfhounds: a clinical, hormonal and spermatological study.

On the basis of clinical observations, Irish wolfhounds were suspected as being subject to a relatively high incidence of soft testicular consistency and low semen quality. Thirty-seven Irish wolfhounds and 67 dogs of other breeds (control group) were therefore examined. Conventional andrological studies were performed in both groups, these included libido testing, palpation and measurement of testes and semen evaluation. Semen evaluation was performed both manually and by videomicrographic analysis. Testosterone concentrations were measured both before and after human chorionic gonadotropin challenge in the Irish wolfhounds. The Irish wolfhounds had lower libidos than the control group. More Irish wolfhounds (21.2 per cent) exhibited low semen quality than the control group (6.1 per cent). Soft testicular consistency occurred more frequently in Irish wolfhounds (25.7 per cent) than in the control group (10.5 per cent). In the control group, bodyweight correlated significantly with total sperm count. Serum testosterone concentration did not correlate with semen quality parameters.

Bovine uterine, cervical and ovarian androgen receptor concentrations. Correlation with estrogen and progesterone receptor concentrations.

Bovine cytosol androgen receptor (ARC) concentrations were examined simultaneously in various regions of the uterus and in ovarian tissues of cows, and were related to cytosol estrogen (ERC) and progesterone receptor (PRC) concentrations and circulating steroid levels. ERC concentrations were 3-7-fold and PRC concentrations 13-29-fold those of ARC in bovine endometrial and myometrial tissues. When serum progesterone levels were low, both endometrial and myometrial ARC, endometrial ERC, and endometrial and myometrial PRC concentrations were higher (p < 0.05) than those observed during higher progesterone concentrations. Because serum 5 alpha-dihydrotestosterone (5 alpha-DHT) concentrations were higher during the luteal phase, it is possible that ARC was down-regulated by this natural ligand at this phase of the cycle. There were no differences between uterine horns in endometrial or myometrial ARC concentrations. Bovine cervical and ovarian stromal tissue also contained ARC, and the concentrations were about the same as in the endometrium and the myometrium. The relative binding affinities (RBAs) of some steroid hormones towards ARC in vitro were: the synthetic compound R1881 (146%), 5 alpha-dihydrotestosterone (100%), testosterone (75%) while estradiol-17 beta, progesterone and dexamethasone had lower RBAs (2, < 1, < 1% respectively). Cytosol androgen receptor concentrations correlated significantly with cytosol progesterone (PRC) and estrogen receptor (ERC) concentrations, both in the endometrium and myometrium. These data show that androgens, such as 5 alpha-DHT, may participate the endocrine regulation of bovine reproductive tissues.

Relationship between testicular measurements, body weight and semen quality in young dairy bulls.

Dairy bulls, 322 Ayrshires (Ay) and 85 Friesians (Fr), were studied at the age of 11 months. Of the bulls, 286 Ay-bulls and 80 Fr-bulls produced semen of acceptable quality for use in A.I. Scrotal circumference, tonometer measure, scrotal fold thickness, 1-year body weight and testicular palpation were used to predict unsuitable bulls for A.I. Non-return rate was used as a measure of fertility. Scrotal fold thickness and 1-year weight had no significant correlation with fertility or semen quality. Scrotal circumference had a significant positive correlation with fertility. Tonometer ratio had a significant negative correlation with fertility. Testicular palpation was the best basis for predicting bulls with poor semen quality in this study. Twelve bulls were recorded as having testicles of different sizes, 1 testicle being more than 20% bigger than the other. Only 2 of these 12 bulls produced semen of acceptable quality. One of these 2 bulls was, after slaughter, diagnosed as having a hereditary testicle disease. Friesians were shown to have significantly higher fertility than Ayshires.

Ultrasonography revealing the accumulation of rete testis fluid in bull testicles.

Ultrasonography was used for diagnosing accumulation of rete testis fluid in live bulls. When 447 bulls of Ayrshire breed selected for artificial insemination were studied by ultrasonography, eleven were detected in which the ultrasonograms visualized accumulation of rete testis fluid in the testicles. In 7 bulls the accumulation (spermiostasis) was bilateral and in 4 unilateral. In only four out of 18 testicles, macroscopically epididymal cysts were seen after slaughter. At the age of 16 months four bulls with bilateral spermiostasis were azoospermic. When studied by ultrasonography, the rete testis of normal testicles was echogenic and narrow but in affected testicles anechogenic and wide. Nine of the affected bulls were sons of three fathers. We suggest that spermiostasis is hereditary in Ayrshire bulls and, as in the goat, is progressive by nature.

Three types of acrosomal aberrations of bull spermatozoa and their relation to fertility.

The effect of acrosomal aberrations of the spermatozoa of Finnish Ayrshire bulls on the corrected non-return rate within 60 days of the first 500 inseminations was studied. The material consisted of sperm samples examined by the artificial insemination societies. All samples had been accepted for use in artificial insemination. One Giemsa-stained slide was studied for each of the 95 bulls concerned. Samples showing distinct acrosomal defects were studied by electron microscopy. Three different types of acrosomal aberration were found. One was obviously associated with subfertility in all 6 bulls in which it was detected.

Bovine steroid hormone and SHBG concentrations postpartum and during the oestrous cycle.

Changes in consecutive estimates of milk progesterone concentrations and serum steroid hormone and sex hormone-binding globulin (SHBG) concentrations in the postpartum period were examined in Finnish Ayrshire and Friesian dairy cows which were divided according to feeding into a hay group and a silage group. Milk progesterone concentrations rose above 10 nmol/l, indicating the start of ovarian luteal activity, slightly earlier in the silage group (28.4 +/- 8.7 (S.D.) days, n = 19) than in the hay group (33.4 +/- 10.3, n = 28) after calving. Likewise, the first normal oestrous cycles began slightly earlier in cows fed with silage. On the other hand, no differences in the beginning of ovarian luteal activity were observed between the breeds. Serum oestradiol-17 beta, oestrone, testosterone, 5 alpha-dihydrotestosterone (5 alpha-DHT), pregnenolone and progesterone concentrations were fairly unchanged during postpartum anoestrus after uterine involution and before ovarian cyclic activity. After first ovulation, considerable increases in milk and serum progesterone concentrations were observed. The increase was accompanied by elevations in serum pregnenolone and 5 alpha-DHT concentrations. In the late luteal phase, progesterone, 5 alpha-DHT and pregnenolone concentrations rapidly declined, leading to low hormone levels in pro-oestrus. Thereafter, serum pregnenolone and 5 alpha-DHT concentrations slightly increased during the follicular phase. On the other hand, oestradiol-17 beta concentrations were elevated in pro-oestrus and decreased after that, being lowest at met-oestrous. Serum testosterone concentrations appeared to be unchanged during postpartum anoestrus and over the oestrous cycle. Serum SHBG concentrations were unchanged during postpartum anoestrus and over the oestrous cycle, as well as in pregnant animals. The serum SHBG concentrations were about double those found in women with normal menstrual cycles, whereas oestradiol concentrations were much lower. At present, it cannot be explained how the biological effects of oestradiol become evident under such conditions.

Tail stump sperm defect in Ayrshire bulls: morphogenesis of the defect.

Three cases of tail stump sperm defect have been presented in Finnish Ayrshire bulls. The semen samples of the bulls showed markedly reduced number of sperm with almost total absence of tails. Transmission and scanning electron microscopy of the testicular samples revealed the testicular origin of the defect. The anlagen of the implantation fossa, proximal and distal centrioles, connecting piece, nuclear ring, manchette and annulus were demonstrated, but the axoneme formation was completely blocked. A separate population of spermatids showed nuclear bending and was possibly destroyed by the phagocytic activity of Sertoli cells. The pedigree of the bulls supports the concept that the defect is inherited by a single recessive autosomal gene.

Detomidine in pregnant cows.

Evidence that the course of gestation in dairy cattle is not influenced by the administration of detomidine, a novel sedative and analgesic agent.

Ovarian cysts in dairy cattle--observations of symptoms and milk progesterone values; therapy with GnRH and a combination of GnRH and PG.

Ovarian cysts of 59 cows were treated with an intramuscular dose of 50 micrograms GnRH analogue. Half of the cows were 9 days later further treated with 0.5 mg cloprostenol. The clinical symptoms were recorded. Whole milk progesterone was monitored on day of the treatment (GnRH) and on day 7. Most of the cows that had a high progesterone level showed no clinical symptoms of the ovarian cysts. The majority of the cows (50/59) had a low progesterone status (less than 10 nmol/l) at the time of the initial treatment. In only 7 cows the level had not risen by day 7. The cows of GnRH + PG group came into heat sooner (P less than 0.01) and conceived rather well; the treatment-conception interval was not, however, significantly shorter than in the GnRH group.

Ovarian cysts in dairy cattle--some aspects of diagnosis, treatment with GnRH and HCG and subsequent milk progesterone values.

Ovarian cysts in 87 cows were treated with an intramuscular dose of 50 micrograms GnRH analog or 2500 IU HCG. Milk progesterone values were determined on day 0, 7 and 10 post-treatment. The cows were divided into three progesterone profile categories: I: low--rising progesterone, II: continually low progesterone, III: initially high progesterone. Fertility was restored about equally in groups I and III. Cows in group II came into heat quickly but conceived poorly. HCG and GnRH were equally effective in restoring the fertility. It was difficult to evaluate the progesterone status of the cow with rectal examination. Vaginoscopy seemed to be a somewhat more reliable method.

Ultrastructure of a tail stump sperm defect in an Ayrshire bull.

The sperm cells in the ejaculate of a sterile Ayrshire bull were studied by light microscopy as well as scanning and transmission electron microscopy. The spermatozoa showed an almost total lack of tails, whereas the heads appeared morphologically normal. The cytoplasmic residue at the caudal end of the head contained numerous membrane structures as well as mitochondria and incomplete elements of the proximal centriole and striated column. The basic disturbance appears to be a hereditary defect in the spermiogenesis.