Canine-specific tail-in, head-out sperm agglutination.

An interesting pattern of tail-in, head-out sperm agglutination was identified in a Brucella canis seronegative subfertile dog. Centrifuged seminal plasma from this dog could induce a similar pattern of agglutination in six other dogs, but not in ejaculates from a single stallion and two rams. The agglutination pattern was short-lived and appeared to depend on motility of spermatozoa, although intensity of agglutination may have been affected by concentration of agglutinating factor.

Curtailing parturition observation and performing preparturient cesarean section in bitches.

Properly planned elective cesarean section (CS) in bitches is considered safe and justified for some breeds. Therefore, planning a scheduled (fixed date and time) preparturient CS in bitches belonging to a subpopulation where a CS is unavoidable, seems justified. The first day of cytological diestrus (D0) was used to predict the date of parturition. The aims of this study were to (1) compare the mortality of puppies delivered by preparturient CS to those delivered by parturient CS, (2) determine the extent to which a preparturient CS (performed at 08:00 on D57, while the cervix is closed) would shorten gestation, (3) compare the level of progesterone at the time of preparturient CS to that at the time of parturient CS, (4) compare the change in hematocrit before and after CS for parturient- and preparturient CSs. Out of 99 gestations for which D0 was known and a preparturient CS planned, the CS was performed at the scheduled time in 61%, before the scheduled time because cervical dilatation had started in 32% and before the scheduled time in 7% because the bitches had started showing signs of impending parturition, although their cervices were still closed. This study showed high neonatal survival ratios and good Apgar scores after preparturient CS with 99% of puppies delivered by preparturient CS born alive and 98.8% surviving to 2 h. Performing preparturient CSs shortened gestation by four to 52 h. Progesterone level was significantly higher at the time of preparturient CSs than at the time of parturient CSs. Further studies are required to determine whether preparturient CSs on D57 are routinely safe in all breeds, does not affect long term survival of the puppies and to timeously identify bitches in which parturition starts prior to the date and time for the scheduled elective preparturient CS.

Is the biparietal diameter of fetuses in late gestation too variable to predict readiness for cesarean section in dogs?

Correct assessment of readiness for cesarean section is essential for timing elective cesarean section during late pregnancy in the bitch. In humans, biparietal diameter is sufficiently precise and accurate and used in a clinical setting daily. The objectives of this study were to determine whether fetal biparietal diameter in late gestation in the dog could be used to predict readiness for cesarean section by having reached a minimum cut-off value and to correlate the biparietal diameter to birth weight. The biparietal diameter of 208 puppies in 34 litters from 31 English bulldog bitches and 660 puppies in 78 litters from 70 Boerboel bitches were measured immediately after delivery by cesarean section, performed at full term, using digital calipers. At the same time the birth weight of the same 208 English bulldog puppies and 494 of the same Boerboel puppies in 59 litters from 54 bitches was measured by means of an electronic scale. With a cesarean section, all the puppies in a litter are delivered simultaneously and readiness for cesarean section must be determined for a litter. The minimum, median and maximum biparietal diameter varied from 21.1 to 47.8, 32.9 to 50.0 and 34.2-58.2 mm, respectively, among English bulldog litters and from 18.4 to 48.7, 35.5 to 49.7 and 39.8-54.3 mm among Boerboel litters. This large variation suggests that biparietal diameter is too variable within and among litters to be useful as a means of determining readiness for cesarean section.

The precision of predicting the time of onset of parturition in the bitch using the level of progesterone in plasma during the preparturient period.

Precise prediction of the time of onset of parturition in the bitch is of clinical importance. Many parturition management cases in clinical practice are presented in the last two weeks of pregnancy without a reliable estimate of the parturition date. The aim of this study was to assess the value of a single progesterone level in the blood plasma from a preparturient bitch to predict the time of onset of parturition. The temporal relationship between the decrease in the plasma progesterone levels and the time of cervical dilatation (TCD)-which correlates to the onset of stage 1 of parturition-was evaluated in 25 bitches in the preparturient period. Among bitches destined to reach TCD within 12 h there is a 2% probability of having a plasma progesterone level of 15.8 nmoL/L or above and a 6% probability of having a level of 8.7 nmoL/L or above. Conversely, if the level is below 8.7 nmoL/L there is a 99% probability of reaching TCD within 48 h and if the level is below 3.18 nmoL/L there is a 100% probability of reaching TCD within 24 h. These results allow the veterinary obstetrician to make prompt decisions in the management of parturition.

Estimated impact of multiple conceptuses per follicle on fecundity in the bitch.

Multiple conceptuses from one follicle due to multi-ovular follicles or monozygotic twins inflate the ratio between the numbers of conceptuses and corpora lutea and possibly the effect ascribed to experimental treatment. The aim of this study was to estimate the impact of multiple conceptuses per follicle on fecundity in the bitch. The numbers of conceptuses and corpora lutea of 105 bitches originated from 7 published experimental studies and of 132 from ovariohysterectomies done in a private practice and a welfare organisation. Ninety five bitches, producing 597 conceptuses, had at least as many conceptuses as corpora lutea; 83 had as many, 10 had one more and 2 had 2 more. Bootstrap resampling on these 95 bitches let us to conclude that 12.6% of bitches are expected to produce more oocytes that are each capable of yielding a conceptus than the number of follicles that ovulate and that 2.35% of conceptuses are expected to be in excess of the number of follicles that ovulate. Applying the results of the current study to 2 earlier studies showed that multiple conceptuses from one follicle may, at maximum, have increased the effect ascribed to prostatic fluid by 0.022 and 0.024 conceptuses per corpus luteum, which is minor in relation to the magnitude of the ascribed effects of 0.34 and 0.22 conceptuses per corpus luteum. The number of conceptuses relative to the number of corpora lutea provides a valid and precise measurement of fertility in the bitch.

Puppy survival and vigor associated with the use of low dose medetomidine premedication, propofol induction and maintenance of anesthesia using sevoflurane gas-inhalation for cesarean section in the bitch.

The safety of an anesthetic protocol consisting of medetomidine hydrochloride (7 µg/kg iv) as premedicant, propofol, (1-2 mg/kg iv) as induction agent and sevoflurane, at 2% in oxygen for maintenance of anesthesia was studied in 292 cesarean sections (CSs) and 2232 puppies delivered. Medetomidine effects were reversed using atipamezole hydrochloride at 50 µg/puppy sc immediately following delivery and in the bitch iv immediately following surgery. The protocol's safety for puppies was expressed using survival immediately, 2 h and 7 d after delivery, and Apgar scores (measurement starting 15 min after delivery of the last puppy). The maternal survival rate was established immediately, 2 h and 7 d after cesarean section (CS). The CSs included 148 on Boerboel, 84 on English bulldog and 60 on other purebred bitches, which resulted in 1378, 541 and 313 puppies, respectively. Boerboel, English bulldog and other purebred bitches yielded 97.39%, 96.67% and 91.69% live puppies at delivery, 95.43%, 88.35% and 89.78% alive by 2 h and 89.19%, 79.11% and 84.03% alive by 7 d. Sixteen (1.16%), 32 (5.59%) and 4 (1.28%) malformed Boerboel, English bulldog and other purebred puppies were euthanized. Thirty five, 18 and 26, Boerboel, English bulldog and other purebred puppies were stillborn respectively, of which 12, 9 and 15, respectively had been discovered dead upon ultrasound examination immediately before CS. After correction for fetuses found dead on ultrasound examination and malformed euthanized puppies, 98.21%, 95.60% and 94.30% of Boerboel, English bulldog and other purebred puppies survived until 2 h and 91.78%, 87.17% and 88.26% until 7 d. Two-hour survival rates are negatively correlated to the proportion of puppies in a litter with scores of 8 or below (r = 0.14, P = 0.01, n = 292 litters) and tends to be positively correlated to the lowest Apgar score in a litter (r = 0.11, P = 0.05, n = 292 litters). This study shows that medetomidine hydrochloride in the protocol used is a safe premedicant in bitches prior to cesarean section and is associated with good puppy vigor as well as 2 h and 7 d puppy survival rates. The use of medetomidine as premedicant permitted use of less than half the dose of propofol usually required as induction agent.

The precision of peri-oestrous predictors of the date of onset of parturition in the bitch.

Precise prediction of the date of onset of parturition in the bitch is clinically important. The study compared the precision with which four peri-oestrous predictors predict the date of onset of parturition. The predictors evaluated in 24 bitches were: the date of the first or only day of the LH surge, the date on which the concentration of progesterone in the blood plasma first exceeded 6 nmol/L, the date on which the concentration of progesterone in the blood plasma first exceeded 16 nmol/L and the date of onset of cytological dioestrus. Among the 24 bitches, the date of onset of cytological dioestrus predicted the date of onset of parturition with greater precision than the other three predictors. Following the evaluation of another 218 intervals between the onset of cytological dioestrus and the date of onset of parturition, it was shown that the onset of cytological dioestrus predicted the date of onset parturition with a precision of ±1 d, ± 2 d and ±3 d in 88%, 99% and 100% of the 242 pregnancies. This study concludes that the first day of cytological dioestrus is a useful predictor of the date of onset of parturition.

The first case of genetically confirmed monozygotic twinning in the dog.

Monozygotic twinning has not previously been genetically confirmed in the dog. This case report describes the finding of two viable male monozygotic foetuses within one placental site during caesarean section. Their umbilical cords attached to a single placenta. Genetic profiling using a total of 38 microsatellite markers, as well as amelogenin and SRY for sex determination, revealed identical DNA profiles, whether derived from blood or tissue (buccal swabs) samples. To the best of our knowledge, this is the first report of monozygotic twinning in the dog confirmed using DNA profiling.

Hematocrit changes in healthy periparturient bitches that underwent elective cesarean section.

Hematocrits were measured before each of 406 cesarean sections performed on 324 bitches at term and again after crystalloid fluid therapy administered at 35 mL/kg over 1½-2 hours starting from induction. The mean hematocrit was 44.2% (95% confidence interval [CI] 43.8%-44.6%) before cesarean section and 37.8% (95% CI 37.3%-38.2%) after cesarean section and fluid therapy, with a mean decrease of 6.4% points (95% CI 6.1%-6.7%) over all 406 cesarean sections. These results provide the clinician with clear guidelines of the normal expected ranges of hematocrits in bitches before and after cesarean section. Results of this study show that bitches have hematocrits at term that are at the lower end of the normal reference ranges for nonpregnant dogs and that there is no true anemia of pregnancy. It is therefore suggested that if late term bitches present with anemia, other causes besides pregnancy should be considered.

Validation of merocyanine 540 staining as a technique for assessing capacitation-related membrane destabilization of fresh dog sperm.

The aim of this study was to determine whether flow cytometric evaluation of combined merocyanine 540 and Yo-Pro 1 (M540-YP) staining would identify viable dog sperm that had undergone membrane stabilization known to be associated with capacitation in other species, and whether such destabilization is detected earlier than when using the tyrosine phosphorylation and ethidium homodimer (TP-EH) stain combination with epifluorescence microscopy. Semen from nine dogs was collected and incubated in parallel in bicarbonate-free modified Tyrode's medium (-BIC), medium containing 15 mM bicarbonate (+BIC), dog prostatic fluid, and in PBS. Aliquots for staining were removed at various time points during incubation of up to 6 hours. Staining with M540-YP allowed the classification of dog sperm as viable without destabilized membranes, viable with destabilized membranes, nonviable without destabilized membranes, or nonviable with destabilized membranes. The percentage of viable sperm detected using EH (83.5 ± 1.37%; mean ± SEM) was higher than when using YP (66.7 ± 1.37%: P < 0.05; n = 54 semen samples). On the other hand, M540-YP identified a higher percentage of viable sperm with destabilized membranes than TP-EH (75 ± 1.76% vs. 35 ± 1.70%: P < 0.05; n = 54 semen samples). Staining with M540-YP indicated a rapid increase in the percentage of viable sperm with destabilized membranes, reaching a maximum during the first 30 minutes of incubation in +BIC. For all other treatments (i.e., -BIC, prostatic fluid, and PBS), the peak in the percentage of viable sperm with destabilized membranes was reached as much as 90 to 210 minutes later than incubation in +BIC. The lowest percentage of viable sperm showing signs of capacitation was recorded during incubation in PBS. We conclude that YP identifies sperm committed to cell death earlier than EH, and that the M540-YP stain combination identifies membrane destabilization known to be associated with capacitation in other species earlier than the TP-EH stain combination.

Prediction of the optimal time for insemination using frozen-thawed semen in a multi-sire insemination trial in bitches.

The aims of the study were to determine which of Days 5, 6 or 7 after the blood plasma progesterone concentration (PPC) of bitches first reached 6-9 nmol/L (Day 0) yield the highest fertility and whether day of insemination affects the gender ratio of conceptuses. Six bitches were inseminated on Days 5 and 6 and 6 on Days 6 and 7. Ten million progressively motile frozen-thawed sperm from each of 5 dogs were pooled for the first insemination. The same number of sperm from 5 other dogs were pooled for the second insemination. Only one batch of semen from each dog was used on all bitches, which largely prevented any effect of male and semen. Twenty-three autosomal microsatellites and the amelogenin gene were used to determine the paternity and gender of the conceptuses. Pregnancy rate was 100%. Out of 103 ovulations 66 conceptuses were conceived (conception rate: 64%). The proportion of available oocytes fertilised was 0.11, 0.56, and 0.27 for Days 5, 6, and 7, respectively. The odds of fertilisation was 16.7 and 4.2 times higher from insemination on Day 6 compared to Day 5 (P<0.001) and Day 7 (P = 0.013), respectively. The numbers of male- and female conceptuses were equal (33 each) and gender was independent of insemination day (P = 0.18). This study suggests that intrauterine insemination of bitches should best be done 6 days after PPC first reaches a value between 6 and 9 nmol/L with a second insemination one day later.

The progression of small-follicle reserves in the ovaries of wild African elephants (Loxodonta africana) from puberty to reproductive senescence.

This study aimed to determine whether the follicle reserve in the ovary of the African elephant declines progressively after puberty and whether its depletion constrains the fertility of older females. Elephant ovaries were fixed in 4% neutral buffered formalin and small-follicle counts made using stereological protocols. Excepting a slight rise in small-follicle numbers between 16 and 25 years of age, there was a trend for follicle numbers to fall from puberty to 70 years. Reproductive status did not impact significantly on small-follicle numbers (P=0.31). The number of early primary follicles, initially higher in number than true primary follicles, fell from post-puberty to nil at 45 years of age. Six of the seven oldest animals in the study showed signs of recent ovarian activity in the form of antral follicles, corpora lutea or large corpora nigra. The four oldest elephants (mean age 69 years) had a median small-follicle count of 11,113. In summary, it appears that the elephant ovary is capable of supplying oocytes for ovulation right up to the time of death at the age of maximum life expectancy, although the follicle reserve becomes depleted in some older elephants.

Development of the germinal ridge and ovary in the African elephant (Loxodonta africana).

The follicular reserve and its ontogeny in the elephant are of interest because elephants have the longest reproductive life of all land-based mammals. They also have the longest recorded pregnancy, which allows a protracted view of the series of significant events involved in the development of the embryonic and fetal gonads. The large elephant population of Zimbabwe provided the opportunity to collect conceptuses from elephants culled for management reasons and hunted professionally. Five embryos aged 76-96 days and the ovaries of four fetuses aged 4.8-11.2 months were fixed in 4% buffered formalin and studied by conventional histological sectioning and a stereological protocol to calculate the follicle reserve of each fetus. These observations enabled the conclusion that the migration of primordial germ cells into the indifferent gonad terminates at around 76 days of gestation while entry of oogonia into meiosis along with first follicle formation starts at around 5 months. Peak numbers of follicles are present by mid-gestation towards the end of the 6-month mitotic-meiotic transition period. It appears that the cortex of the elephant fetal ovary at mid-gestation (11 months) has already reached a developmental stage exhibited by the ovaries of many other mammals at full term.

Which fields under a coverslip should one assess to estimate sperm motility?

Under field conditions the motility of bull semen often has to be estimated under a coverslip on a microscope slide. This study was aimed at determining which combination of fields under coverslips provides measurements of sperm motility that best represent the motility in semen specimens as measured in a specially designed chamber for use in a computer-assisted sperm analyzer (CASA). We measured the motility (percentages motile, progressively motile, and aberrantly motile spermatozoa) in each of four straws of frozen-thawed semen from each of 10 bulls five times, ranging from 5 to 120 minutes after thawing with each bull by straw by time combination yielding one semen specimen. Motility was measured in duplicate in a Hamilton, Thorne IVOS CASA; once in each of 12 fields equally spaced along the equatorial radius of a coverslip (Field 0 at the edge and Field 11 at the center) and once in each of eight equally spaced fields along the equator of a Leja 4 chamber designed for use in a CASA. We used the weighted average motility of all fields in a chamber as gold standard and compared it to the average motility of each the following combinations of fields under the coverslip: all 12 fields, Fields 2 to 4, Fields 2 and four, Field 3 and the center three fields. The concordance correlation coefficient (CCC) was determined between the motility in each combination of fields under coverslips and the chambers as a reproducibility index, which evaluates the agreement between the readings under the coverslips and the gold standard readings in the chambers (n = 187 for each CCC). We performed pairwise comparisons of the CCCs (P < 0.005 for each comparison) and established that the average motility under all 12 fields better reproduced the motility in the chamber than the center three fields or Field 3. The averages of Fields 2 to 4 and Fields 2 and 4 reproduced chamber motility as well as the average of all 12 fields, except for the percentage motile sperm, where the average of all 12 fields was better. Using the average motility of Fields 2 and 4, 50% of estimates fell within 6%, 4% and 3% above or below the percentages motile, progressively motile and aberrantly motile spermatozoa in the Leja 4 chamber, 80% of estimates fell within 12%, 8% and 7% thereof and 95% fell within 23%, 13% and 12% thereof. In conclusion, for the method of spreading semen under a coverslip and the range in motility values used, this study shows that the average of the motility over the 12 fields along the equatorial radius under a coverslip provides the best estimate of the motility of a semen specimen, while the average of Fields 2 and 4 is also suitable for the subjective estimation of motility under field conditions, although the estimated motility is expected to fall within 6% above or below the motility of the specimen in only 50% of semen specimens.

The distribution of small preantral follicles within the ovaries of prepubertal African elephants (Loxodonta africana).

BACKGROUND: Data on the distribution of primordial (single layer of squamous granulosa cells), early primary (some granulosa cells cuboidal) and primary (all granulosa cells cuboidal) follicles, grouped together as small follicles (SF) within the ovary of the elephant is lacking, yet such information is necessary to be able to estimate accurately the total numbers of small follicles in the ovaries of elephant throughout their lifespan. AIM: To determine if the density of SF differs between ovaries, between the surfaces of an ovary, or between the interpolar and intermarginal zones of an ovary. MATERIALS/METHODS: Stereological techniques were employed on 25µm thick histological sections of the ovaries recovered from 12 prepubertal elephant calves aged 2 months to 4.5 years. Cell densities were calculated using the optical brick method and Cavalieri's principle for volume calculation. RESULTS: The density of SF (numbers of SF per unbiased counting frame [UCF]) did not differ between the left (1.11±0.39 (mean±sd)) and right (1.10±0.39) ovaries (P=0.82, n=12), or between the lateral (median 1.24; interquartile range 0.85-1.39) and medial (1.03; 0.76-1.36) surfaces of the ovary (P=0.22, n=24) or among the 5 segments of the ovary between the two poles (P=0.20, n=24). The third of the cortex nearest to the mesovarial margin of the ovary had fewer small follicles per UCF (0.85; 0.51-1.28) than the middle third (1.01; 0.78-1.42; P=0.034), and the third adjacent to the free margin (1.27; 0.79-1.51; P=0.0024), n=24 per group. CONCLUSION: Providing a random sample is taken from the full interpolar and intermarginal dimensions of ovary of a non-pregnant elephant, the density of small follicles throughout the cortex may be accurately measured using stereological techniques applied to one of its surfaces.

Early primary--rather than primordial follicles constitute the main follicular reserve in the African elephant (Loxodonta africana).

Information on the ovarian follicle reserve in the African elephant (Loxodonta africana) is lacking. This study set out to determine the ratios of early preantral follicles and their relative dimensions in the ovaries of 16 African elephant aged 10-34 years. The ovaries were sectioned histologically. Follicles were counted and classified according to expansion of the pre-granulosa cells. Early primary follicles were the most common (75.8%±11.8%), followed by true primary follicles (23.8%±11.8%), whereas primordial follicles were the most rare (<2%). Measurements made on at least 100 early preantral follicles from each animal (n=1464) indicate that growth in oocyte and nuclear diameters started with transition to the true primary stage P<0.01. This, together with the observed ratios between the three types of early preantral follicles suggest that both classical primordial and early primary follicles contribute to the ovarian reserve in the African elephant.

Effect of heterologous seminal plasma and semen extenders on motility of frozen-thawed ram spermatozoa.

Ram seminal plasma increases the fertility of frozen-thawed ram spermatozoa deposited into the cervix. The aim of the current study was to compare the effect of ram seminal plasma to that of bull seminal plasma, dog prostatic fluid, protein-free TALP TrilEq (Triladyl with 0.5 mt of Equex STM paste added to each 100 mt) and heat-treated skim milk on longevity and percentages of progressively motile and aberrantly motile frozen-thawed ram spermatozoa. Three ejaculates from each of 6 rams were extended in TrilEq, pooled and frozen in straws as a single batch per ram. One hundred and eight straws (3 straws from each ram for each fluid) were thawed in random order. Once thawed, a straw was emptied into a tube with 0.85 ml of the appropriate fluid at 37 degrees C and kept at that temperature for 6 h. Motility was assessed at x200 magnification immediately (time zero) and 2, 4 and 6 h after thawing. Progressive motility decreased from each time to the next (P < 0.05) and was 39.0 % (0 h), 26.0 % (2 h), 19.6 % (4 h) and 12.6 % (6 h); SEM 1.24, n = 108 for each group. Ram seminal plasma resulted in higher progressive motility than bull seminal plasma, lower than milk, and similar to the other fluids. Ram seminal plasma resulted in lower aberrant motility than protein-free TALP and similar aberrant motility to other fluids. The effect of ram seminal plasma and dog prostatic fluid was very similar. The effect of ram seminal plasma on the fertility of frozen-thawed ram spermatozoa deposited into the cervix is not due an exceptionally beneficial effect on the motility of spermatozoa.

Detection of antibodies against epidermodysplasia verruciformis-associated canine papillomavirus 3 in sera of dogs from Europe and Africa by enzyme-linked immunosorbent assay.

The role of papillomaviruses (PVs) in the development of canine cancers is controversial. However, recently a novel canine PV (CPV3) was detected in a dog affected with a condition reminiscent of epidermodysplasia verruciformis (EV). The aim of the present study was to investigate the seroprevalence of CPV3 by using generic enzyme-linked immunosorbent assays (ELISAs) for the detection of antibodies against either canine oral PV (COPV) or CPV3. Therefore, the capsid proteins of both PV types were expressed as glutathione S-transferase fusion protein antigens and adsorbed to glutathione-casein-coated ELISA plates. After showing that PV type-specific antibodies could be detected in the sera from dogs with confirmed COPV or CPV3 infection, CPV3- and COPV-seropositive samples were detected in two sets of canine sera collected in Switzerland and South Africa, respectively. We found specific antibodies against COPV and CPV3 among the tested sera and also a large number that were positive for both antigens. The seroprevalences of PV antibodies of 21.9% (COPV) and 26.9% (CPV3) among the tested dogs from South Africa were higher than those among the dogs from Switzerland at 10.5% (COPV) and 1.3% (CPV3). Our data suggest a need for further CPV-related seroepidemiological surveys in different countries, especially in the context of clinical manifestations and possible breed predispositions. For this purpose, the newly developed ELISAs can be a useful tool.

The comparative prevalence of five ixodid tick species infesting cattle and goats in Maputo Province, Mozambique.

This study compares the prevalence of ixodid tick species on cattle and goats in Maputo Province. Adult ticks as well as the nymphs of three species, and only the adults of two species were collected from sets of five cattle at 21 localities throughout the province and compared with those collected from similar sets of goats at the same places. Amblyomma hebraeum adults and/or nymphs were present on cattle and on goats at all 21 localities, and 90 cattle and 22 goats were infested with adult ticks. Rhipicephalus (Boophilus) microplus adults and/or nymphs were collected from cattle at 20 and from goats at 15 localities, and 92 cattle and 34 goats were infested [Chi-square test (chi2), P<0.001]. The total length of several maturing female R. (Boophilus) microplus collected from cattle and goats exceeded 5 mm, indicating that they successfully engorge on both host species. Rhipicephalus appendiculatus adults and/or nymphs were present on cattle at 15 and on goats at 13 localities, but 28 cattle and only one goat were infested with adult ticks (chi2, P<0.001). Adult Rhipicephalus evertsi evertsi were recovered from cattle at 20 and from goats at 17 localities, and 74 cattle and 69 goats were infested. Adult Rhipicephalus simus were collected from cattle at 18 and from goats at 11 localities (Fisher's exact test, P=0.04), and 60 cattle and 14 goats were infested (chi2, P<0.001). These findings underscore the advisability of including goats in acaricide application programmes designed for the control of tick-borne diseases in cattle at the same locality.

A simple multidimensional system for the recording and interpretation of sperm morphology in bulls.

This study reports on the development of a data capture sheet for recording the sperm morphology of bulls. The arrangement of the data capture sheet permits the simultaneous recording of the viability and morphology of spermatozoa, and the recording of multiple defects in spermatozoa. Apart from deriving the prevalence of each type of defect, the sheet permits the derivation of the percentages spermatozoa with nuclear defects, defects of the acrosome or tail, respectively, as well as the percentages morphologically normal and normal viable spermatozoa. The arrangement of the data capture sheet further permits the rapid and easy interpretation of the sperm morphology regarding the stage of development, site and extent of malfunction of the reproductive organs, the prognosis for change in the sperm morphology over time and the extent to which defects may be compensated for by normal spermatozoa and the likely fertility of the particular semen sample. The data capture sheet permits a multidimensional, holistic interpretation of the sperm morphology of a bovine semen sample.