Observations on semen quality of dogs in the tropics

Semen was obtained from eight mongrels and 17 purebred dogs kept in a tropical climate. The mean spermatozoal output per ejaculate was 303.6 +/- 138.2 and 602.9 +/- 466.2 million, respectively. Values for individual progressive motility, live and abnormal spermatozoa were comparable with those obtained in temperate regions. The type and frequency of spermatozoal abnormalities are illustrated.     

Total antioxidant capacity and protein peroxidation intensity in seminal plasma of infertile and fertile dogs

The aim of this study was to evaluate the total antioxidant capacity and protein peroxidation intensity in seminal plasma of infertile and fertile dogs. The study was conducted on 10 infertile and 10 fertile dogs of various breeds. Infertility was defined as conception failure at least three matings with different bitches. Semen was collected by manual manipulation. The sperm concentration and motility parameters were evaluated using CASA Hamilton Thorne, Vers. IVOS 12.3. The morphology of spermatozoa and the percentage of live and dead sperm cells were assessed microscopically, total antioxidant capacity and the content of SH‐groups in seminal plasma were determined spectrophotometrically, the contents of protein peroxidation markers in seminal plasma, bityrosine and formylokinurenine, were determined using spectrofluorimetric methods. Sperm concentration and total sperm count were significantly (p < 0.05) lower in infertile dogs than in fertile dogs (99.92 ± 3 0.05 × 10⁶/ml vs. 282.07 ± 48.27 × 10⁶/ml; 214.19 ± 114.74 × 10⁶ vs. 747.57 ± 210.94 × 10⁶, respectively). The percentage of spermatozoa with normal morphology and the most determined motility parameters differed significantly (p < 0.05) between both groups. The mean values of total antioxidant capacity in the seminal plasma were significantly (p < 0.05) lower (19.95 ± 20.94 vs. 25.66 ± 23.18 µmol/g protein), whereas the mean contents of bityrosine and formylokinurenine in seminal plasma were significantly (p < 0.05) higher in infertile dogs than in fertile dogs (3.71 ± 4.83 µg/mg protein vs. 1.55 ± 2.00 µg/mg protein and 0.37 ± 0.45 µg/mg protein vs. 0.14 ± 0.08 µg/mg protein, respectively). In conclusion, the obtained results suggest that the poor semen quality and infertility in dogs could be associated with lowered total antioxidant capacity and increased protein peroxidation in seminal plasma as a consequence of oxidative stress.     

The ostrich (Struthio camelus) ejaculate--effects of the method of collection, male age, month of the season, and daily frequency

1. Over three breeding seasons on a farm in Poland, semen was collected from 11 ostriches using the dummy and the teaser method to study the effects of the method of collection, male age, month in the breeding season, and daily collection frequency on ejaculate characteristics.

2. A total of 259 ejaculates were collected, with an average volume of 1·28?±?0·6 (±SEM) ml. Sperm concentration was 3·34?±?0·08?×?10⁹/ml, the total number of spermatozoa 4·32?±?0·22?×?10⁹, and motility 4·56?±?0·04.

3. There was no difference in ejaculates collected by the dummy and teaser methods, but the between-individual variation was considerable. Ejaculate characteristics increased with male age and varied between months, with little evidence for seasonal decline. Daily collections for 10 days did not affect sperm output.

4. The results open up avenues for further research on development of a viable protocol for artificial insemination in ostriches and efficient semen storage.

5. The between-male variation suggests that the ejaculate output could be maximized through selection.     

The effect of vitamin a supplementation on seminal characteristics and vitamin a absorption in stallions

Fourteen mature stallions were paired based on age and pretreatment spermatozoal output. One member of each pair was assigned to either 1) control (3 ml corn oil) or 2) treated (132,000 IU retinyl palmitate in 3 ml corn oil) experimental groups. Treatments were added to oat rations every other day. Seminal characteristics (gel free volume, gel volume, total seminal volume, percent progressively motile spermatozoa, number of spermatozoa per ml, percentage morphologically normal spermatozoa and spermatozoal membrane stability) and total scrotal width of each stallion were recorded before (February) and after three months of vitamin A supplementation (June). Plasma vitamin A was measured at 0,6,12,24, and 48 hours following the first and last treatments to document absorption. There were no treatment effects (p>.05) on seminal characteristics or scrotal width. Seasonal increases were recorded in gel-free volume, total seminal volume, percent spermatozoal motility, total spermatozoal output, percentage of morphologically normal spermatozoa, and total scrotal width. Plasma vitamin A was lower during the second collection period (June) than the first (February) in both treatment groups. Peak plasma vitamin A was observed 48 hours following ingestion of the first dose of the vitamin but at 12 hours following the last treatment.     

Characteristics of Buck Semen with Regard to Ejaculate Numbers, Collection Intervals, Diluents and Preservation Periods

To determine the number of ejaculates which can be collected within a 20‐min period after the smallest number of days of sexual rest, and a good diluent to preserve semen for routine AI, five mature Black Bengal bucks were used in three experiments. In experiment 1, semen from the bucks were collected by using artificial vagina at homosexual mounts as many times as possible during 20 min. The ejaculate numbers 1, 3 and 4 (or 5 when the buck could produce it) were examined for important semen characteristics. The mean ejaculate volume, density, mass activity, sperm motility, sperm concentrations, total spermatozoa/ejaculate, proportion of spermatozoa with normal acrosome, midpiece and tail, and the proportion with normal head morphology varied between 267 and 342 µl, 4.1–4.5 (1–5 scale), 4.1–4.2 (1–5 scale), 77–79%, 4187 × 10⁶–5064 × 10⁶/ml, 1140 × 10⁶–1746 × 10⁶, 91–94% and 99%, respectively, depending on the collection number of the ejaculate. The difference between the ejaculates was significant only with respect to volume (p < 0.05). In experiment 2, semen was collected from the bucks successively during 20 min after 1, 2, 3 and 4 day intervals, and the first ejaculates were evaluated for the above‐mentioned semen characteristics. Semen collected after 2 or more day intervals had significantly higher volume, sperm concentration and total spermatozoa/ejaculate (p < 0.05). In experiment 3, pools of two to three ejaculates were diluted (1 : 5; semen : diluent) in splits with glucose‐citrate‐egg yolk (GCEY), Tris‐fructose‐egg yolk (TFEY) or skim milk (SM) and preserved at +4 to +7°C. Before chilling or after 0 (15 min chilling), 1, 2, 3 and 4 days of preservation, semen was evaluated for motility and proportion of normal spermatozoa with respect to acrosome, midpiece and tail. In data pooled across the bucks, the sperm motility was better in GCEY and TFEY than in SM, and the proportion of normal spermatozoa was higher in SM than in the others (p < 0.05). However, the differences in proportion of normal spermatozoa between diluents were not significant when the data were analysed separately within preservation periods. The sperm motility consistently dropped after 1 day of preservation (p < 0.01); the motility remained 50% or more up to 4 days in TFEY, 3 days in GCEY and only 2 days in SM. The proportion of spermatozoa with normal acrosome, midpiece and tail, which was generally quite high ( 90%), decreased after 3 days of preservation (p < 0.01). We conclude that Black Bengal bucks can be collected three times during 20 min, every 3 days, and that buck semen holds good motility and proportion of normal spermatozoa up to 3 days in GCEY or TFEY at 4 to 7°C.     

Effect of Body Weight, Age and Breeding History on Canine Sperm Quality Parameters Measured by the Hamilton-Thorne Analyser

During the last decade, several computer assisted sperm analysis (CASA) systems have been validated for canine sperm quality assessment. Regarding the impressive possibilities of these systems, further research is required to determine which CASA measurements are of clinical importance in canine andrology. In the present study, the sperm quality parameters obtained by the Hamilton-Thorne Semen Analyser (Ceros 12.1; HTR) were correlated with the body weight and the age of the dogs. Moreover, the sperm quality parameters of dogs with a different breeding history were compared. The sperm-rich fraction was collected from 111 dogs of 50 different breeds, which were presented at our department. Immediately after collection, the concentration, the total sperm output (TSO) and 13 different sperm motility and velocity characteristics were measured by the HTR. The percentage of live spermatozoa and the spermatozoal morphology were examined on eosin/nigrosin stained smears. Based on their breeding history, the dogs were divided in three groups: 'fertile' (n = 60), 'subfertile' (n = 17) or 'not used for breeding' (n = 34). Significant (p < 0.05) correlations were established between the body weight of the dogs and the TSO (r = 0.245) and velocity curvilinear (VCL; r = -0.220), respectively. The age was negatively correlated with the percentage of normal spermatozoa (r = -0.203; p < 0.05). The correlations with all the other evaluated sperm parameters were low and not significant. Significant differences between the 'fertile' and the 'subfertile' group were found for all of the evaluated sperm quality parameters (except for BCF, LIN, STR and MEDIUM). In conclusion, dogs tend to produce ejaculates with a lower percentage of normal spermatozoa with increasing age and dogs with higher body weights produce ejaculates with a higher TSO and a lower VCL. Significantly poorer sperm characteristics were found for dogs with lower in vivo fertility results.     

Semen Characteristics and Plasma Levels of Testosterone after Bilateral Vasectomy in Bucks

The effects of bilateral vasectomy on the seminal characteristics were assessed in six bucks of the Canarian breed. In addition, we tried to establish the effects of vasectomy on the plasmatic concentrations of testosterone and the libido of the bucks. Semen samples were collected once a week from 8 weeks before to 16 weeks after vasectomy; blood samples were collected prior to vasectomy, and then at once and 1 week after vasectomy and every 2 weeks from the week 4 to the end of the experiment. One week after the vasectomy, ejaculated spermatozoa were non‐motile and the percentage of live spermatozoa was below 5% in all vasectomized males; in addition, the total number of cells/ejaculate was 3100 × 10⁶ and 30 × 10⁶ spermatozoa in the control and vasectomized males, respectively. Our results suggest that the vasectomized males may be used as oestrus detectors, without risks of accidental fecundating, only 1 week after vasectomy. Before vasectomy, no significant differences were observed in plasma levels of testosterone between the vasectomized and control males (5.4 ± 1.2 and 3.9 ± 1.4 ng/ml, respectively); from 4 to 12 weeks after vasectomy, a marked decrease in the testosterone concentration in all males (vasectomized and control bucks) was observed. From 12 weeks after vasectomy until the end of the experiment, four of the vasectomized males and the control males recovered their normal libido. The results suggest that vasectomy did not exert a remarkable effect on the steroidogenic functionality of the testicle.     

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.     

Does a Boar's Season of Birth Determine Semen Parameters and Reproductive Performance?

This article studies the effect of a boar's birth season and breed on semen parameters and its further reproductive performance. Research material consisted of 72 boars from three breeds (24 Polish Large White PLW, 24 Polish Landrace PL, 24 Duroc × Pietrain D×P). During the whole period of the study, selected semen parameters were analysed: semen volume, spermatozoa concentration, total number of spermatozoa, total number of motile spermatozoa, number of insemination doses and also reproductive indicators: farrowing rate, total born litter size, total number of piglets born live and still, and average piglet weight. Boars born in the winter and summer months demonstrated the highest spermatozoa concentrations (383.25 and 392.37 × 10⁶/ml), total number of spermatozoa (91.75 and 93.21 × 10⁹), total number of motile spermatozoa (76.10 and 77.99 × 10⁹) and number of insemination doses (24.53 and 24.89; p ≤0.01). Statistically lower values for these parameters were observed for boars born in the spring and especially in autumn (p ≤0.01). The significant impact of birth season on farrowing rate (p ≤ 0.05) and average piglet weight (p ≤ 0.05) was confirmed for PLW boars. For the PL breed, only the total number of piglets born live was proven to be significantly affected (p ≤ 0.05). No impact of birth season was shown on semen quality or reproductive performance for D×P boars. In our study, we showed that the birth season of a boar had a more impact on the level of semen parameters, and less on the reproductive performance indicators. The results indicated that both the quality of semen and reproductive performance varied in terms of the study factors, as well as between individual breeds of boars involved in the experiment.     

Use of a computerized system for evaluation of equine spermatozoal motility

Three ejaculates from each of 3 stallions were used to evaluate a computerized system (Hamilton-Thorn motility analyzer; HTMA) for measuring equine spermatozoal motility. Variance components (ejaculate-within-stallion, chamber-within-ejaculate, and microscopic field-within-chamber) were determined for each stallion after diluting ejaculates to 25 x 10(6) spermatozoa/ml with a skim milk-glucose seminal extender. The HTMA was compared with frame-by-frame playback videomicrography (VIDEO) for determining: percentage of spermatozoal motility and spermatozoal number in microscopic fields; curvilinear velocity and straight-line velocity of individual spermatozoa for 5 track types; and repeatability of those velocity measurements. The effect of spermatozoal number per microscopic field on incidence of intersecting spermatozoa and the outcome of intersecting spermatozoa also were evaluated. Greatest variability in motility measures was generally attributed to the microscopic field-within-chamber component. The HTMA was highly correlated with VIDEO for estimation of spermatozoal numbers per microscopic field (r = 0.99; P less than 0.001) and motility (r = 0.97; P less than 0.001); however over the entire range of spermatozoal numbers, the HTMA yielded higher spermatozoal numbers per microscopic field (P less than 0.05) and higher motility (P less than 0.05) than did VIDEO. The HTMA- and VIDEO-derived measurements of curvilinear and straight-line velocities were highly correlated for all spermatozoal track types, but both measures were higher (P less than 0.05) by use of the HTMA than by use of VIDEO for most track types. For 3 of 5 track types, measurements of curvilinear and straight-line velocities were less variable (P less than 0.05), using the HTMA, rather than VIDEO.(ABSTRACT TRUNCATED AT 250 WORDS)     

Seasonal influences on gonadal and extragonadal sperm reserves in Small East African zebu (Bos indicus) bulls in Ethiopia

Summary Body weight and scrotal circumference (SC) data were takenante mortem and genitalia collected after slaughter from Small East African zebu (SEAZ) bulls slaughtered during the wet (n=46) and the dry (n=53) seasons. Bulls slaughtered during the wet season were significantly heavier (47 kg) and had significantly larger SC measurements (3·3 cm) than those slaughtered during the dry season. Mean (±s.e.m.) paired testes weights were 233·7±13·8 and 292·8±11·3 g and epididymal weights 26·8±0·9 and 35·9±1·1 g in bulls slaughtered during the dry and wet seasons, respectively. Daily sperm production rates and epididymal sperm reserves were 2·2±0·1×10⁹ and 3·0±0·1×10⁹; and 16·1±0·3×10⁹ and 17·6±0·4×10⁹ in bulls slaughtered during the dry and wet seasons, respectively. These differences were significant. It was concluded that season affected reproductive capacity of zebu bulls probably due to variations in the quality and quantity of nutrition. However, the confounding effects of ambient temperature and nutrition on reproductive capacity of zebu bulls in tropical regions need further examinations.

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Résumé Le poids vif et la circonférence scrotale de petits zébus males à courtes cornes d'Afrique de l'est a été mesuré anti-mortem au cours de la saison humide (n=46) et de la saison séche (n=53). Parallèlement, des organes génitaux ont été prélevés après abattage. Les veaux abattus pendant la saison humide étaient incontestablement plus lourds (47 kg) et les mesures de leur circonférence scrotale étaient bien plus importantes (3,3 cm) que celles des animaux abattus au cours de la saison sèche. Les poids moyens (+s.e.m.) des deux testicules étaient de 233,7±13,8 et 292,8±11,3 g; les poids de l'epididyme étaient de 26,8±0,9 et 35,9±1,1 g chez les males abattus durant la saison sèche et la saison humide. Les taux quotidiens de production de sperme ainsi que les réserves de l'epididyme étaient de 2,2±0,1×10⁹ et 3,0±0,1×10⁹ et 16,1±0,3×10⁹ et 17,6±0,4×10⁹ chez les males abattus durant la saison sèche et la saison humide. Les différences étaient significatives. On a conclu que les saisons affectaient la capacité de reproduction des zébus males probablement à cause des variations qualitatives et quantitatives de l'alimentation. Cependant, les effects interactifs de la température ambiante et de l'alimentation sur la capacité de reproduction des zébus males sous des climats tropicaux nécessitent de plus amples examens. Resumen Se tomaron el datos sobre peso corporal y la circunferencia escrotal (CE) ante-morten y después de sacrificados, en toros Cebú peque?os de Africa del Este. Para el efecto, se sacrificaron 46 animales durante la estación lluviosa y 53 durante la estacioń seca. Los toros sacrificados durante la estación seca fueron más pesados (47 kg) y tuvieron CE mayores (3·3 cm), que aquellos sacrificados durante la estación seca. El promedio de peso de los testículos fue de 233·7±13·8 y 298·8±11·3 g y de los epidídimos 26·8±0·9 y 35·9±1·1 g en toros sacrificados durante la estación seca y lluviosa, respectivamente. La tasa diaria de producción de esperma y las reservas epididimales fueron 2·2±0·1×10⁹ y 3·0±0·1×10⁹ y 16·1±0·3×10⁹ y 17·6±0·4×10⁹ en toros sacrificados durante la estación seca y lluviosa, respectivamente. Las diferencias fueron significativas. Se concluye que la estación afecta la capacidad reproductiva de los toros Cebú, probablemente debido a la cantidad y calidad de la nutrición. Sin embargo, la interacción entre ambiente y nutrición sobre la capacidad reproductiva del Cebú en regiones tropicales, necesita más estudios.

     

Assessment of Suitable Porcine Semen for Freezing,According to the Ejaculate Characteristics in the Iberico × Landrace Breed

A total of 35 ejaculates were studied in order to assess the suitability of porcine semen for freezing according to the ejaculate characteristics. The effects of the freezing procedure were identified; a decrease in motility and acrosome quality was found after thawing. The best results on motility were linked to the ejaculates with a volume of less than 100 ml of the sperm‐rich fraction, a concentration lower than 450 × 10⁶ spermatozoa/ml and an agglutination score below 2. However, the best normal apical ridge (NAR) was found when the volume of the sperm‐rich fraction was greater than 150 ml. For this reason, an intermediate volume of the sperm‐rich fraction of the ejaculate for the best motility and the best NAR, a concentration lower than 450 × 10⁶ spermatozoa/ml and a rate of agglutination below 2 should provide the best quality after freezing. This study also attempted to determine whether a positive effect of ejaculate selection on the overall freezing performance might be expected.     

Induction and characterization of acrosome reaction in equine spermatozoa

Equine spermatozoa were incubated in a chemically defined medium for 8 hours. The medium preserved spermatozoal viability, as assessed by total spermatozoal motility, progressive spermatozoal motility, and spermatozoal exclusion of eosin stain. Effects of time and divalent cation ionophore, A23187, on the occurrence and character of the spermatozoal acrosome reaction were determined. Two light microscopic assays, a triple-stain technique and a chlortetracycline fluorescence assay, were calibrated with transmission electron microscopy for detection of the acrosome reaction. Incubation time and A23187 addition increased the percentage of acrosome reactions in sperm populations (P less than 0.05).     

Breeding soundness examination of North American bison bulls

OBJECTIVE: To evaluate the breeding soundness examination procedure in plains bison bulls. DESIGN: Multiyear (1993 through 1997) cross-sectional clinical procedure evaluation. ANIMALS: Two hundred thirty-four 28- to 30-month-old bison bulls at Custer State Park. PROCEDURE: Breeding soundness examinations were performed on all bison bulls using 1992 Society for Theriogenology guidelines for beef cattle semen evaluation and reproductive tract examination. Linear and logistic regression analyses were used to detect correlations and associations among breeding soundness examination variables. RESULTS: Scrotal circumference (SC) was significantly correlated with body weight, percentage of normal spermatozoa, percentage of primary spermatozoal defects, and percentage of motile spermatozoa. Scrotal circumference was positively associated with increased odds of semen collection, satisfactory motility (> or = 30% motility), satisfactory morphology (> or = 70% normal spermatozoa), and simultaneous satisfactory motility and morphology. Receiver-operator characteristic curve analysis selected 29 cm as the optimal SC cutoff most predictive of simultaneous satisfactory spermatozoal motility and morphology. Only 36.2% (83/229) of the bison bulls had a SC of 29 cm or greater and satisfactory spermatozoal motility and morphology. CLINICAL IMPLICATIONS: SC is a good indicator of adequate spermatozoal motility and structure in bison. We recommend use of 30% spermatozoal motility, 70% normal spermatozoal morphology, and 29-cm SC as minimal satisfactory measurements for breeding soundness examinations of 28- to 30-month-old bison bulls that have been raised on forage-based nutrition.     

Correlation of testicular artery Doppler velocimetry with kinetics and morphologic characteristics of epididymal sperm in dogs

Sperm quality can be affected by a reduction in testicular blood flow, which can be measured by Doppler ultrasonography. The aim of this study was to correlate the Doppler velocimetry of the testicular artery with kinetics of the epididymal spermatozoa in dogs. Twenty-two dogs (44 testicles) were evaluated by Doppler ultrasonography in five regions of the testicular artery before orchiectomy. Spermatozoa were recovered by the epididymal tail compression technique and analysed for kinetics on a computer-assisted semen analysis (CASA system). Morphology (modified Karras) and sperm membrane integrity were analysed by eosin–nigrosine staining. Data were analysed by Pearson's correlation test (p < .01). The mean total motility was 69.0% ± 17.7, progressive motility was 43.7% ± 14.7, average path velocity (VAP) was 127.0 µm/s ± 20.7, curvilinear velocity (VCL) was 221.0 µm/s ± 31.1, and sperm velocity index (SVI) was 389.9 ± 56.1. There were positive correlations between the peak systolic velocity (PSV) in the proximal supratesticular region with the SVI (r = .529), VCL (r = .555) and VAP (r = .473), and a negative correlation with the percentage of slow spermatozoa (r = −.463). The results suggest that the testicular artery blood flow velocity can positively affect the speed of spermatozoa movement. For the first time, we have correlated sperm kinetics with the Doppler evaluation of the testicular artery in dogs.     

Influence of different anaesthetic protocols over the sperm quality on the fresh,chilled (4°C) and frozen‐thawed epididymal sperm samples in domestic dogs

This study assessed the influence of three different anaesthetic protocols on semen quality obtained from the epididymis. Sixty male dogs undergoing to routine sterilization were assigned to three anaesthetic protocols: thiopental group (TG, n = 20), propofol group (PG, n = 20) and ketamine–dexmedetomidine group (KDG, n = 20). Immediately after orchidectomy, the cauda epididymides and vas deferent ducts were isolated and then a retrograde flushing was performed to collect spermatozoa. In experiment 1, after the initial evaluation of the semen (sperm concentration, sperm motility and the percentages of live spermatozoa, abnormal spermatozoa and acrosome membrane integrity), semen samples were diluted in Tris‐glucose‐egg yolk extender and chilled for 48 hr, and the sperm motility was assessed at 6, 24 and 48 hr. In experiment 2, semen samples were diluted in Tris‐glucose‐egg yolk extender and chilled for 24 hr, and then samples were frozen in two extenders with different glycerol concentrations, to reach a final concentration of 50–100 × 10⁶ spermatozoa ml^?1, 20% egg yolk, 0.5% Equex and 4% and 5% glycerol, respectively. Mean values of total sperm concentration, sperm viability and the percentages of intact acrosome and abnormal spermatozoa were not significantly different between experimental groups, and therefore, the anaesthetic protocols assessed did not affect sperm parameters mentioned above. However, our study confirmed a detrimental effect of the use of thiopental (TG) over the total sperm motility (p < 0.05) and progressive sperm motility (p < 0.05) of the fresh and chilled epididymal sperm samples. The anaesthetic protocols including the application of propofol or ketamine–dexmedetomidine can be used to recover sperm in domestic canids without significant changes in sperm quality compared when semen is collected routinely and these techniques could be applicable to endangered wild canids.     

Influence of Inseminate Components on Porcine Leucocyte Migration In Vitro and In Vivo after Pre- and Post-Ovulatory Insemination

A post‐breeding migration of leucocytes (PMN) into the uterus is considered to be an important reason for sperm losses. Minimizing such effects may be necessary for successful insemination with low sperm numbers, as required with sex‐sorted spermatozoa. We examined the magnitude of PMN influx 3 h after pre‐ or post‐ovulatory insemination with various combinations of seminal plasma (SP), semen extender Androhep? (AH; Minitüb, Tiefenbach, Germany) and sperm preparations (S). Pre‐ovulatory inseminations with preparations containing 98% AH caused a massive influx of PMN, independent of whether spermatozoa were present (628 ± 189 × 10⁶ leucocytes/uterine horn) or not (580 ± 153 × 10⁶). Post‐ovulatory, 98% AH caused a comparable immigration only in the absence of sperm cells (AH: 569 ± 198 × 10⁶, AH+S: 162 ± 102 × 10⁶). The presence of SP significantly dampened the numbers of recruited uterine leucocytes. The reaction to all inseminates containing 98% SP both with and without spermatozoa, used before ovulation (SP: 14 ± 6 × 10⁶, SP+S: 73 ± 27 × 10⁶) and after ovulation (SP: 60 ± 32 × 10⁶, SP+S: 51 ± 33 × 10⁶) did not differ significantly from controls using phosphate buffered saline (PBS) (pre‐ovulatory: 1 ± 1 × 10⁶, post‐ovulatory: 11 ± 9 × 10⁶). Quantitative in vitro transmigration assays with blood‐derived PMN proved that AH‐induced leucocyte migration into the uterus to be not as a result of direct chemotaxis, because, on account of the chelator citrate, AH significantly inhibited the transmigration towards recombinant human Interleukin‐8 (rhCXCL8) (AH: 14 ± 5% migration rate vs controls: 37 ± 6%, p < 0.05). Supernatants of spermatozoa incubated in PBS for 1, 12 or 24 h showed neither chemoattractive nor chemotaxis‐inhibiting properties. SP at ≥0.1% [v/v] significantly inhibited the in vitro transmigration of PMN. With respect to in vivo migration of neutrophils, the striking difference in the results between semen extender and seminal plasma suggests that adaptation of extender composition is needed to reflect more closely the in vivo regulatory potential of natural seminal plasma.     

Cryopreservation of Nili‐Ravi buffalo (Bubalus bubalis) semen in AndroMed® extender; in vitro and in vivo evaluation

The study was designed to evaluate AndroMed^® for the freezability and fertility of Nili‐Ravi buffalo semen. Semen was collected from four adult Nili‐Ravi buffalo (Bubalus bubalis) bulls for 3 weeks (replicate). Semen ejaculates from each buffalo bull were divided into three aliquots. One aliquot was used for evaluation of motility, plasma membrane integrity, livability, viability, DNA integrity and normal apical ridge. Remaining two aliquots were diluted (37°C; 50 × 10⁶ spermatozoa/ml) in tris‐citric egg yolk or AndroMed^® extender and cryopreserved in 0.5 ml French straws. After thawing, per cent post‐thaw motility (47.9 ± 0.8, 49.2 ± 1.7), plasma membrane integrity (44.4 ± 1.2, 46.8 ± 1.8) and normal apical ridge (81.4 ± 0.3, 83.2 ± 0.3) were recorded similar (p > .05) in tris‐citric egg yolk and AndroMed^® extender. Higher (p < .05) percentage of sperm livability (70.5 ± 1.4 and 64.4 ± 1.0), viability (67.5 ± 1.5 and 61.5 ± 0.6) and DNA integrity (97.0 ± 0.3 and 93.4 ± 0.21) were recorded in AndroMed^® compared to tris‐citric egg yolk post‐thaw. Values for all the aforementioned spermatozoal quality parameters were observed lower (p < .05) in frozen‐thawed compared to fresh semen irrespective of the experimental extenders. Fertility rates of buffalo semen did not differ (p > .05) either cryopreserved in tris‐citric egg yolk or AndroMed^® extender (45.5% vs. 49%). It is concluded that AndroMed^® is capable in protecting the buffalo bull sperm during freeze‐thawing process and can be adopted safely for routine use replacing the tris‐citric egg yolk extender in artificial insemination programme.     

Inherited copper toxicosis in the Bedlington terrier: the prevalence in asymptomatic dogs

Copper toxicosis in the Bedlington terrier is an inherited defect. This paper describes the investigation of 62 Bedlington terriers, none of which had shown any clinical signs of liver disease, in order to assess the prevalence of copper toxicosis in the breed in the United Kingdom. Twenty one (33·9 per cent) of the dogs investigated had abnormally high levels of copper in the liver. No reliable circulating haematological or biochemical parameters were found to identify those dogs with increased hepatic copper levels and the diagnosis could only be established by liver biopsy. Affected dogs had liver copper levels of between 257·5 and 2558·0 μpg per g of wet weight (1163·8 ± 164 μg/g, mean ± SEM) compared with normal dogs which had between 9·9 and 118·6 μg/g of wet weight (49·0 & 4·4 μg/g, mean ± SEM). Copper accumulation in the liver of affected dogs could also be detected on histological examination using special stains.