The spatio-temporal distribution of aromatase cytochrome in ovary throughout the canine oestrous cycle.

CONTEXT: New animal welfare legislation and ethical guidelines encourage alternative approaches for canine contraception, instead of surgical gonadectomy which is considered invasive and unjustified in healthy dogs. AIMS: Reversible contraception might be achieved by inhibition of aromatase (CYP19), an enzyme catalysing the conversion of androgens to oestrogens. This study provides insights into the spatio-temporal expression and distribution of aromatase in canine ovarian tissue. METHODS: Ovarian tissue was collected from 39 healthy and sexually mature bitches during different stages of the oestrous cycle: pro-oestrus (n =8), oestrus (n =12), dioestrus (n =9) (luteal phase) and anoestrus (n =10). Localisation of cytochrome P450 aromatase was determined by immunohistochemistry. KEY RESULTS: Aromatase activity in the dog is high during pro-oestrus, ovulation and early dioestrus. Comparing types of follicles and corpora lutea, the highest aromatase abundance was found in antral follicles and luteinising follicles, whereas corpora lutea and early antral follicles showed an intermediate presence of the enzyme. Interesting was the high abundance of aromatase in luteinising theca interna cells, prevailing over granulosa cells. CONCLUSIONS AND IMPLICATIONS: Understanding of cells involved in oestradiol production is important for targeted inhibition of oestradiol synthesis, possibly offering an approach for contraception and suppression of oestrus.

Immune cell characterization in spontaneous autoimmune orchitis in dogs.

With a prevalence of up to 35% in dogs with reproductive problems, azoospermia is one of the most important reasons for male infertility. Non-obstructive azoospermia, without clinical symptoms, but histopathological damage of the testicular tissue and immune cell infiltration is referred to as spontaneous autoimmune orchitis (AIO) in the literature. Published cases in dogs describe immune cell infiltration; however, there is no consent about the involved immune cell types. We aimed to characterize immune cells in testicular biopsies of dogs with AIO (n = 9) and to compare them to those in testicular specimens from healthy control dogs with normospermic ejaculates (CG; n = 5). Immunohistochemistry was performed using specific antibodies against CD3, PAX5, MAC387, IgG and IgM to proof the presence of T lymphocytes, B lymphocytes, macrophages and early and late plasma cells, respectively. Presence of immune cells in healthy testicular tissue was low and restricted to T lymphocytes and macrophages in the interstitium with the latter also being found within the blood vessels. Different to this, AIO samples revealed presence of all investigated immune cells, underlining lymphoplasmacytic nature of chronic asymptomatic immune-mediated orchitis. Canine spontaneous AIO is characterised by a significantly increased number of immune cells, namely ≥33 immune cells/mm2 (sensitivity/specificity: 100% based on our data). The pathogenesis of canine AIO is hypothesized to be as follows: 1. Macrophages initiate AIO via T lymphocyte activation. 2. T lymphocytes lead to a "delayed type immunological response" and development of AIO. 3. Invaded B lymphocytes later differentiating to plasma cells are responsible for the second humoral immunological response and cause progression of AIO. Different to the situation in CG, T lymphocytes and plasma cells were identified within the seminiferous tubules indicating that disruption of spermatogenesis in AIO might be related to invading immune cells. Testicular biopsies provide an essential tool in the diagnosis of spontaneous AIO.

Uterine expression of smooth muscle alpha- and gamma-actin and smooth muscle myosin in bitches diagnosed with uterine inertia and obstructive dystocia.

Primary uterine inertia (PUI) is the most common type of dystocia in dogs. We hypothesized that PUI develops because of lower than normal expression of the basic contractile elements in the uterus, i.e., smooth muscle (SM) α- and γ-actin and SM-myosin, and that the expression of these proteins is influenced by the number of fetuses present in utero. Full-thickness inter-placental uterine biopsies were collected during Cesarean sections from dogs with PUI (n = 11), and from bitches with obstructive dystocia (OD) still presenting strong labor contractions (designated as the control group, n = 7). Relative gene expression was determined by semi-quantitative real-time (TaqMan) PCR, and protein localization by immunohistochemistry. Gene expression between PUI and OD bitches, and between PUI bitches carrying small, large, or average number of fetuses according to their breed, were compared. Uterine SM-γ-actin and SM-myosin mRNA levels were significantly higher in PUI than in OD dogs, while SM-α-actin did not differ. PUI bitches carrying large litters had lower uterine SM-γ-actin gene expression than those with small litters (P = 0.008). Immunostaining for SM-actin isoforms and SM-myosin was present in the myometrium, and localization pattern and staining intensity appeared similar in the PUI and OD groups. All proteins stained in blood vessels, and SM-γ-actin was also present in endometrial luminal and glandular epithelium. In conclusion, higher uterine SM-γ-actin and SM-myosin gene expression in PUI bitches, compared with OD dogs, might be an indication of abnormal progression with labor. Whether this is the cause of PUI due to an intrinsic error of the myometrium not becoming committed to labor, or the consequence of inadequate endocrine or mechanical stimuli, is not clear. Litter size was previously shown to be one of the risk factors for the development of uterine inertia in dogs, and our findings suggest possible differing uterine pathophysiology of PUI with respect to litter size.

Expression of PTGS2, PGFS and PTGFR during downregulation and restart of spermatogenesis following GnRH agonist treatment in the dog.

Prostaglandins (PGs) and prostaglandin endoperoxide synthase (PTGS) are considered to be relevant for spermatogenesis and steroidogenesis. PTGS2, prostaglandin F synthase (PGFS) and PGF receptor (PTGFR) are investigated in the adult male dog using the model of the GnRH-agonist implant downregulated canine testis and its subsequent restart of spermatogenesis following abolition of treatment (3, 6, 9, 12 weeks after implant removal). On the mRNA level (ratio), PTGS2, PGFS and PTGFR expression did not differ between downregulation, different stages of recovery of spermatogenesis and untreated adult controls (CG). On the protein level, Sertoli and Leydig cells in all samples and some peritubular cells stained immunopositive for PTGS2. In the tubular compartment, the percentage of the PTGS2-immunopositive area (PIA) and the mean PTGS2-staining intensity (gray scale, GS) did not differ between groups but in the interstitial compartment, the PIA (p = 0.0494) and the GS (p < 0.0001) were significantly upregulated during early recrudescence (week 3/6). Comparing downregulation by two GnRH-agonist implants with juvenile controls (JG) and CG, the mRNA expression (ratio) did not differ. In the tubular compartment, the GS (p = 0.0321) was significantly higher at downregulation compared to CG and in the interstitial compartment, the PIA (p = 0.0073) and the GS (p = 0.0097) were significantly higher in JG compared to downregulation/CG. PTGS2, PGFS and PTGFR mRNA and PTGS2 protein are regularly expressed in the adult, juvenile and downregulated canine testis and downregulation and subsequent recrudescence affect PTGS2 protein expression mainly in Leydig cells. PTGS2 expression in the downregulated testis resembles the one in seasonal Syrian hamster but not juvenile canine testis.

Bacteriological findings in the canine uterus during Caesarean section performed due to dystocia and their correlation to puppy mortality at the time of parturition.

Canine intrauterine bacteriological flora during dystocia is unknown. Thus, frequency (bacterial growth (not) detected), quality (species and number of different bacterial isolates) and quantity (colony-forming units) of intrauterine bacteria in relation to in utero foetal death in 50 bitches undergoing emergency Caesarean section were investigated. Bacterial growth was quantified from single colonies, (+) (0.5), to strong growth, +++ (3) and was observed in 34 bitches (68%), with Staph. epidermidis (n = 12), Staph. intermedius-group (n = 7), ß-haemolytic streptococci (n = 6), Staph. aureus, α- and γ-haemolytic streptococci (n = 4 each) being most common and one to four bacteria per sample. Regarding the quantity, most often (n = 46) low growth was identified. In bitches with living pups only (group I), mean number of isolates was 0.78 ± 0.83 compared to 1.60 ± 1.10 (living + stillborn pups, group II) and 1.0 ± 1.15 (stillborn pups only, group III) and mean bacterial growth in groups I/II/III was + (1.0, quantity), + (1.4) and ++ (1.6). Taking just positive samples into consideration, mean number of bacterial isolates was significantly higher in group II compared to I (p = .0088). We concluded that the canine uterus cannot be considered free of bacteria during dystocia. Mean numbers of different bacterial isolates and quantity of bacterial growth are higher in bitches with in utero foetal death.

Blood calcium, glucose and haematology profiles of parturient bitches diagnosed with uterine inertia or obstructive dystocia.

Bitches with dystocia most often present with clinical signs of uterine inertia (UI). The aetiology of myometrial dysfunction in most of these cases is still not elucidated. We compared blood ionized calcium (iCa) and glucose concentrations in bitches diagnosed with primary UI (PUI, n = 14), secondary UI (SUI, n = 6) or obstructive dystocia (OD, n = 6), and we described their haematology profiles. Bitches diagnosed with UI had a patent birth canal and delivered no puppies yet (PUI) or only part of the whole litter (SUI). The OD group had no UI and showed strong abdominal contractions. Blood iCa did not differ between the PUI, SUI and OD groups and was not influenced by litter size. There was a significant positive relationship (R2  = .241, p = .013) between iCa concentrations and the dam's body weight. Glucose concentrations were also not significantly different between dystocia groups or influenced by body weight and litter size. Hypocalcaemia was detected in 11 bitches, and hypoglycaemia in two bitches. Pregnancy-associated anaemia was seen in about one-third of the bitches. Eight of 12 dogs had increased platelet counts, and ten had leukocytosis with mature neutrophilia. Although iCa did not differ between dystocia groups, low concentrations may have contributed to the development of UI in some of the small size bitches. Hypoglycaemia was uncommon, and therefore, we consider low glucose concentrations not to have played an important role in the pathogenesis of UI in our study population. Pregnancy-associated anaemia, thrombocytosis, leukocytosis and mature neutrophilia were common findings in otherwise healthy bitches diagnosed with different forms of dystocia.

Effect of dietary vitamin E and selenium supplementation on semen quality in Cairn Terriers with normospermia.

Among others, selenium (Se) and vitamin E (VitE) have been provided to dogs to improve semen quality. However, scientific evidence documenting an effect in dogs is lacking. The aim of this study was to investigate the effect of supplementation of these antioxidants on various ejaculate parameters in a randomized, double-blinded trial using Cairn Terrier males exhibiting normal seminal quality parameters. Three dogs each were fed a standardized diet and supplemented with 0.1 mg Se, 100 mg VitE or 0.1 mg Se + 100 mg VitE/dog for 3 months. Ejaculate analyses (volume, progressive motility, vitality, morphology, concentration) were performed before inclusion (D0) and after 1, 2 and 3 months (+1, +2, +3). At the same time, glutathione peroxidase (GSH-PX) and VitE in seminal plasma (SP) and GSH-PX in blood samples were determined. Vitamin E levels in SP were below the detection limit (1.0 mg/L) in all samples. GSH-PX in blood (164.0-2794.4 IU/L) and SP (18.4-4326.0 IU/L) was highly variable. Supplementation only significantly affected the total percentage of sperm head abnormalities (p = .011). Time significantly affected the percentage of morphologically abnormal sperm (p = .025), sperm head abnormalities (p = .007), proximal droplets (p = .001) and GSH-PX in SP (p = .015). Additionally, a significant interaction between time and group was identified for the percentage of membrane-intact sperm (p = .048), head abnormalities (p = .018), acrosomal defects (p = .043) and proximal droplets (p = .002). Although some effects could be identified for selected parameters, we failed to identify a clear trend about how a 3 months VitE and/or Se supplementation affects semen parameters in normospermic Cairn Terriers.

Long-term effects of GnRH agonists on fertility and behaviour.

This review aimed to summarize the present knowledge about the effects of GnRH agonist slow-release implants (GnRH A-SRI) on fertility and behaviour in male and female dogs and cats with special focus on deslorelin. Following an initial stimulation of gonadotropin and testosterone secretion possibly associated with an improved semen quality, GnRH A-SRI induce long-term depression of fertility in male dogs and cats with, however, a large individual variation in onset and duration of efficacy especially in cats. The GnRH A-SRI furthermore interfere with testosterone-dependent/affected behaviour; a significant positive effect in reducing sexual behaviour and libido, hypersexuality, intermale dominance and excessive territorial urine marking has been described. Rates of improvement of the respective behaviour are comparable to those after surgical castration, making GnRH A-SRI a valuable option to predict castration-related effects on behaviour and to identify animals where surgical castration will not be beneficial. No effect has been seen in reducing aggression towards humans indicating the need for behavioural therapy to control this problem. Effects on spermatogenesis, steroidogenesis and behaviour have by now been shown to be fully reversible. Knowledge in females is more limited, and particularly, the initial induction of a possibly fertile oestrus and individual variation in duration of efficacy remain problems in bitches and queens treated for suppression of fertility. However, long-term suppression of oestrous cycle and fertility seems to be possible with induced effects shown to be reversible including restoration of normal fertility after the end of efficacy/GNRH A-SRI removal.

Changes in serum progesterone concentrations in Bernese mountain dogs and Cavalier King Charles Spaniels during pregnancy.

Progesterone (P4) concentrations during canine pregnancy follow a specific pattern. Although the general pattern is similar, it is likely that breed-specific differences exist. Detailed knowledge about the physiological range of P4 concentrations may be helpful in cases of suspected hypoluteoidism. The aim of this study was to investigate P4 changes during pregnancy in a small and a large breed, to obtain reference values for specific intervals during pregnancy and to test for breed- or body weight-specific differences. We studied P4 concentrations in pregnancies from healthy Bernese mountain dogs (BMDs, n = 6) and Cavalier King Charles Spaniels (CKCSs, n = 6) with a normal reproductive history. Blood samples for P4 were taken to determine the day of ovulation and after confirmation of pregnancy in regular intervals from Days 23 to 29 to Days 60 to 64. Bernese mountain dogs delivered 6.2 ± 2.6 puppies (range: 3-9) 63.4 ± 1.5 (range: 61-65) days after ovulation (excluding data from one BMD with elective c-section) and CKCS delivered 3.3 ± 1.9 puppies (range: 1-5) 63.5 ± 1.1 (range: 62-65) days after ovulation. In general, the P4 concentrations of individual dogs continuously decreased from the first to the last sampling during pregnancy. Respective mean concentrations were Days 23 to 29: 19.2 ± 4.3/22.2 ± 3.9 ng/mL (BMD/CKCS), Days 30 to 34: 15.6 ± 2.3/17.7 ± 5.8 ng/mL, Days 35 to 39: 12.5 ± 2.8/14.1 ± 3.4 ng/mL, Days 40 to 44: 8.9 ± 1.4/11.8 ± 3.7 ng/mL, Days 45 to 49: 7.7 ± 1.6/8.9 ± 1.9 ng/mL, Days 50 to 54: 6.0 ± 1.3/8.7 ± 7.1 ng/mL, Days 55 to 59: 4.7 ± 1.2/5.3 ± 2.8 ng/mL, and Days 60 to 64: 3.69 ± 1.86/2.62 ± 0.42 ng/mL. ANOVA indicated significant differences over time within each breed when considered individually (P < 0.0001 each), but not between breeds although mean P4 was slightly lower in BMD until Days 55 to 59. The present data clearly confirm the previously described P4 pattern during canine pregnancy with highest P4 concentrations obtained in the first interval (Days 23-29) and a subsequent decrease of P4. The lack of a significant rapid prepartal P4 drop might be related to methodological issues (time of last collection in regards to parturition). Other than expected, we failed to proof significant differences in P4 between CKCS and BMD. Further studies are required to confirm the results on a larger population of both breeds, but also other large-sized breeds to test for the hypothesis if BMD might have lower P4 concentrations and smaller litter size compared to other large breeds with larger litter size.

Effect of seminal plasma vesicular structures in canine frozen-thawed semen.

Membrane vesicles (MVs) in the ejaculate have been identified in various species and are considered to affect membrane fluidity due to their characteristic molecular composition. Addition of MV to human frozen semen has been shown to improve post-thaw motility. Similarly, a beneficial effect has been suggested for frozen equine semen. As post-thaw canine semen quality varies widely between dogs, the aim of our study was to test for the effect of addition of canine MV on post-thaw semen quality in dogs. Semen samples from 10 male dogs were purified from MV and prepared for freezing. In experiment 1, three groups were compared: sperm frozen (1) with MV (S1); (2) without MV, but MV added immediately after thawing (S2); and (3) without MV (C). Semen analysis included computer-assisted sperm analysis of motility parameters immediately after thawing (t0), after 10 (t10) and 30 minutes (t30), % living sperm, % membrane intact, % morphologically normal sperm (all t0 and t30). Computer-assisted sperm analysis motility distance and velocity parameters (all P < 0.05) and % living sperm (P < 0.001) were significantly affected by treatment with a temporary increase of distance and velocity parameters at t0 to t10, but a significant decrease of the aforementioned parameters at t30 in samples with MV. In experiment 2, different MV protein concentrations added after thawing were compared: 0.05 mg, 0.1 mg, and 0.2 mg/mL. Computer-assisted sperm motility analysis was performed at t0, t10, and t30. No differences between MV concentrations were identified, only a significant interaction between effect of treatment and time for progressive motility (P < 0.01). Our study identified a short-term beneficial effect of canine MV on post-thaw distance and velocity parameters, whereas at t30 progressive motility, motility parameters and % living sperm were reduced in samples with MV compared to C. The results point to species-specific differences regarding the MV effect on frozen semen and indicate the need for further studies using different semen and MV purification protocols and more frequent analyses. At the moment, addition of MV is not an option to improve post-thaw semen quality in dogs.

Morphological characterisation of vesicular structures in the canine ejaculate.

Membrane vesicles (MV) have been identified in seminal plasma from various species and they are thought to have a significant impact on semen quality and fertilisation. Although recently presence of MV has been also described in the canine ejaculate, detailed knowledge on their morphology is missing by now. This is, however, needed to provide a basis for detailed biochemical and functional studies as it is generally assumed that different MV populations are responsible for distinct tasks. MV were prepared for light (LM) and transmission electron microscopy (TEM) analysis using samples from normospermic dogs (n=15), hypokinozoospermic dogs (n=2, h) and one castrated azoospermic dog (a). For TEM, a new preparation protocol was used resulting in a higher MV retrieval rate. Using fractionated semen samples, most MV were identified in the second (sperm-rich) fraction in LM. Using pooled ejaculates, three different MV types could be identified in LM: (1) large MV with a marginal accumulation of opaque, granulated material, (2) medium- to small size MV with dense, opaque content and (3) small MV with no further defined contents. No direct contact between sperm and MV could be visualised. In TEM, 11 different MV types were identified based on diameter, structure, contents and electron density of contents as well as presence, number and size of smaller MV inside the MV itself. In normospermic males, secondary vesicles (type i, H, K1/2) included smaller vesicles and had a weighted mean diameter of 409.46 nm; hereof types i, H and K1 were smaller (mean: 287.55 nm, range: 51.25-994.86 nm) and type K2 was larger (mean: 1746.43 nm, range: 1003.66-3289.34 nm). Primary vesicles (mean diameter: 135.29 nm) - without vesicles inside - were differentiated into larger MV (A, B, C1/2) with a mean diameter of 219.63 nm (range: 39.08-1300.13 nm) and small primary MV (F, G) with a mean diameter of 66.12 nm (range: 24.62-99.84 nm). Whereas all mentioned MV were round to oval and mostly double-, rarely multiple-membrane surrounded, one longish primary MV type (L) was identified. In general, small primary vesicles were most common independent of semen quality, but distribution frequency of vesicle types differed between normospermic, pathospermic dogs and the castrated male. Mean weighted diameter of MV was 195.14 nm (range: 24.62-3289.34 nm) in normospermic males with the maximum diameter being smaller in the other dogs (h: 2096.78 nm; a: 1314.06 nm). Our results provide new information about ultrastructure and distribution frequency of canine MV in normospermic males and point to possible differences in MVs depending on semen quality. They provide the basis for further detailed functional analysis of MV subpopulations. Furthermore, the presence of MV in the castrated azoospermic male confirms an at least partly prostatic origin of canine MV.

Suppression of fertility in adult cats.

Cats are animals with highly efficient reproduction, clearly pointing to a need for suppression of fertility. Although surgical contraception is highly effective, it is not always the method of choice. This is predominantly because it is cost-intensive, time-consuming and irreversible, with the latter being of major importance for cat breeders. This article reviews the use of progestins, scleroting agents, immunocontraception, melatonin, GnRH antagonists and finally, GnRH agonists, in adult male and female cats in detail, according to the present state of the art. By now, various scientific and clinical options are available for the suppression of fertility in adult cats and the decision as to which should be chosen - independent of the legal registration of any state - depends on different facts: (i) feral or privately owned animal? (ii) temporary or permanent suppression of fertility wanted/needed? (iii) sex of the animal? New effective and available methods for hormonal contraception include melatonin implants for short-term post ponement of oestrus in adult queens and slow-release GnRH-agonist implants containing deslorelin (Suprelorin(®) ) for short- and long-term contraception in male and female companion and breeding cats.

Status of the down-regulated canine testis using two different GNRH agonist implants in comparison with the juvenile testis.

Testicular function in the dog was down-regulated using two different GNRH agonist implants, with adult and juvenile testes serving as controls. Treatment resulted in an increased percentage of the interstitial area and decreased area of Leydig cell nuclei. Expression of StAR and the steroidogenic enzymes cytochrome P450 side-chain cleavage enzyme (P450scc, CYP11A1) and cytochrome P450 17α-hydroxylase-17,20-lyase (P450c17, CYP17A1) in Leydig cells was blocked at the mRNA and protein level, showing no differences between the two agonists. Staining for androgen receptor (AR) by immunohistochemistry was positive in Sertoli, Leydig and peritubular cells and some spermatogonia, with in situ hybridization confirming expression in Sertoli cells. At the mRNA level, expression of AR was not affected; however, translation was blocked (reduced percentage of AR-positive Sertoli cells), with the number of nuclei in basal position being decreased. In the juvenile testes, mRNA expression of StAR, CYP11A1 and CYP17A1 was higher compared with the other groups but distinctly lower for the AR. At the protein level, the expression was at the limit of detection for StAR; AR-positive Sertoli cells were not detected. Our observations show that the down-regulated testis is different from the juvenile one rather resembling the testicular status in seasonal breeders out of season.

[Exfoliative vaginal cytology in the bitch--indications, procedure, interpretation]. / Die exfoliative Vaginalzytologie bei der Hündin--Indikationen, Durchführung, Interpretation.

Exfoliative vaginal cytology as an essential part of the gynaecological examination is a simple, non-invasive method for the determination of the phases of the oestrous cycle (anoestrus, prooestrus/oestrus, metoestrus) and is additionally applied in cases of silent heat, or suspected ovarian cysts, ovarian remnant syndrome, postpartal disturbances in the endometrial involution or Sticker sarcoma. The exfoliated cells reflect the hormonal, in particular the oestrogenic state, of the bitch. Due to the oestrogenic influence, an increase in cell layers, keratinisation and exfoliation is observed in the follicular phase during prooestrus, such that the 3-4 layered epithelium in anoestrus becomes 20-layered during oestrus. The cells change characteristically in size and nuclear morphology. In anoestrus, predominantly parabasal cells with a large nucleus and homogenous cytoplasm are found. During early prooestrus, single parabasal cells are identified among erythrocytes and intermediate cells. As this phase progresses, the percentage of large intermediate cells and nucleated superficial cells increases. The oestrus is characterised by a high cell number, initially superficial cells with pyknotic nuclei, later anucleated squamous cells that are located in cell nests. The switch to metoestrus is associated with a large number of neutrophil granulocytes and a sudden change of cytology within 24-48 hours. Vaginal cytology can be performed in any practice due to its simplicity and the limited equipment necessary (speculum, cotton wool wad, slide, staining and microscope). Because the results are rapidly available, it is a useful addition to gynaecological examination to differentiate the stage of the cycle (anoestrus, prooestrus/oestrus, metoestrus) and to diagnose infectious, inflammatory and tumorous conditions in the bitch.

Retrospective analysis of canine semen evaluations with special emphasis on the use of the hypoosmotic swelling (HOS) test and acrosomal evaluation using Spermac(®).

Routine semen evaluation includes volume, motility, vital staining for live-dead ratio and pathomorphology including Spermac(®) staining for evaluation of the acrosome. In recent years, depending on the species, also the hypoosmotic swelling (HOS) test has been applied routinely for evaluation of semen quality. In this respect, a significant correlation between the ability of spermatozoa to swell in HOS test and the fertilizing ability has been reported. Also for evaluation of dog semen, reference has been made to the HOS test; however, its correlation to conventional semen parameters so far is discussed controversially. In the present study, the results of 400 semen examinations from stud dogs presented at our clinic were evaluated for their correlations between conventional semen parameters (motility, live/dead ratio, pathomorphology), conventional semen parameters and age, Spermac(®) staining and HOS test, respectively. We found a significant correlation of age and sperm concentration (p < 0.01), total sperm count (p < 0.0001), percentage of progressively motile sperm (p < 0.01) and live spermatozoa (p = 0.012). Furthermore, several correlations between conventional semen parameters were identified. Percentage of sperm with normal acrosome identified by Spermac (®) staining correlated significantly with live spermatozoa (p < 0.0001) and percentage of progressively motile sperm (p < 0.01). A significant correlation was proven between curled tails in HOS test and age (p < 0.001), motility (p < 0.0001), live sperm (p < 0.0001), acrosomal status (p < 0.05), pathomorphology (p < 0.0001) and sperm concentration (p = 0.011). These results indicate that Spermac(®) staining and the HOS test are useful in improving canine semen analysis.

[Perinatal mortality of puppies after caesarean section caused by intrauterine infection]. / Tod eines Wurfs Hundewelpen nach Sectio caesarea aufgrund einer intrauterinen Infektion.

Perinatal mortality in dogs and cats is relatively high. Whereas the death of puppies within the first 3 weeks of life is commonly assumed to be due to infectious causes, peracute death of neonates immediate- ly after parturition or caesarean section results in a high potential for conflict between owner and veterinarian. In this respect, the owner often postulates a wrong anaesthetic regime or a too prolonged duration of surgery. This case report, however, clearly shows that also in the case of immediate perinatal death, infectious causes - e.g. due to intrauterine infection - have to be taken into consideration and that pathological, virological and bacteriological post-mortem examinations of puppies is an important procedure to identify the reason for perinatal death.

The use of a slow release GnRH-agonist implant in female ferrets in season for oestrus suppression.

The jill is a long-day breeder with a constant oestrus without mating. Persistent oestrogen production results in clinical signs of hyperoestrogenism including pancytopenia and death if untreated. As spaying is thought to be related to the development of hyperadrenocorticism, a non-invasive, safe and effective long-term treatment is needed for oestrus suppression in jills. Seven jills in oestrus were treated with a 4.7mg deslorelin implant. Blood samples for estradiol-17ß (E2) and progesterone (P4) determination were obtained before as well as 4 and 8 weeks after treatment; data are given as geometric mean (deviation factor, DF). Mean E2 was 280.2 pmol/L (1.7) before, 36.4 pmol/L (1.4) 4 and 21.6 pmol/L (1.1) 8 weeks after treatment (p < 0.0001). P4 before treatment was 1.4 nmol/L (2.6), 57.8 nmol/L (1.9) on week 4 and 3.8 nmol/L (2.6) on week 8 (p < 0.0001) indicating ovulation had occurred after implant insertion. Oestrous signs within the observation period of up to 32 months remained suppressed.

Restart of steroidogenesis in dogs during recrudescence of testicular function following downregulation with a GnRH-agonist implant.

To date, no details are available concerning the restart of steroidogenesis following the downregulation of testicular endocrine and germinative function by gonadotrophin-releasing hormone (GnRH)-agonist implants. This restart was assessed by determining the expression of steroidogenic acute regulatory (StAR) protein, cytochrome P450 side-chain cleavage enzyme (P450scc) and cytochrome P450 17α-hydroxylase,17,20-lyase (P450c17). The re-establishment of steroidogenesis was initiated by the removal of the GnRH-agonist implant (18.5 mg azagly nafarelin, Gonazon) at 5 months after treatment. Testes were removed at 3-week intervals (weeks 0-24) and four groups were formed according to the stage of spermatogenesis as revealed by the most developed germ cells observed (developmental group [DG] spermatocytes to DG elongated spermatids). Five dogs served as untreated controls. Positive immunostaining for StAR, P450scc and P450c17 was restricted to Leydig cells. Western blot indicated the specifity of the respective antibodies with hints of a expression of canine-specific P450scc and P450c17 proteins. A significant effect of group was observed for a percentage of the immunopositive area (PIA) as an indicator of active Leydig cells for StAR (P<0.05), P450scc (P<0.001) and P450c17 (P<0.001), with PIA being lowest for the DG spermatocytes. With regard to the strength of the immunopositive signal, a significant effect of group was found for P450scc (P<0.01) and P450c17 (P<0.05), with the lowest intensity being observed in DG spermatocytes. At the mRNA level, the upregulation from DG spermatocytes to DG round spermatids was clearly evident but was only significant for P450scc (P<0.05). Thus, downregulation affects the whole cascade of steroidogenesis, whereas withdrawal of inhibition results in a rapid restart, in part indicating a rebound phenomenon.

[Uterine torsion in cattle - frequency, clinical symptoms and theories about the pathogenesis]. / Torsio uteri beim Rind - Häufigkeit, klinische Symptomatik und Theorien zur Pathogenese.

UNLABELLED: Aim of the present study was to summarize the available literature about the incidence, frequency, clinical symptoms and ideas as to the pathogenesis of uterine torsion in the cow. MATERIALS AND METHODS: Analysis of the literature using electronic libraries (Pub Med, Medline), German veterinary medicine journals and obstetrical textbooks. RESULTS: Uterine torsion is a very important maternal reason for dystocia as most cases occur during parturition. The post-cervical torsion (combined uterine and vaginal torsion, Torsio uteri and vaginae) is more commonly diagnosed than an intra-cervical or pre-cervical torsion. Torsions to the left occur more frequently than to the right. Clinical symptoms clearly vary depending on the degree of torsion. The frequency in relation to all parturitions is described as between 0.5 and 1%, whereas the percentage of uterine torsions presented to the veterinarian as a reason for dystocia varies between 2.7 and 65%. The pathogenesis of uterine torsion remains unclear; however, general agreement exists that the cow is predisposed to uterine torsion due to its anatomy. It appears that the Brown Swiss is more often affected than other cattle breeds.