Effective genetic markers for identifying the Escherichia coli F4ac receptor status of pigs.

The F4ac receptor locus (F4acR), which encodes susceptibility or resistance to Escherichia coli diarrhoea, is inherited as an autosomal recessive monogenetic trait. F4acR is localized on pig chromosome 13 (SSC13q41-q44) near the MUC13 gene. Two flanking markers (CHCF1 and ALGA0106330) with a high linkage disequilibrium (LD) with F4acR were found to be effective for the genetic identification of F4ac-resistant pigs in the Swiss Large White breed (one recombinant out of 2034 genotyped pigs). Three recombinant boars, one each from the Duroc, Swiss Landrace and Piétrain breeds, were genotyped with seven different markers and phenotyped by means of a microscopic adhesion test. Only ALGA0072075, CHCF1 and CHCF3 indicated the correct phenotype. To test the effect of the resistance allele on production traits, 530 Large White pigs from the national test station were investigated. A significant difference existed among the F4acR locus genotypes in the intramuscular fat content of the longissimus dorsi muscle, whereas no other production traits were influenced by the resistance allele. The frequency of the CHCF1-C and ALGA0106330-A alleles associated with resistance in the Swiss Large White population was 60%, which is advantageous for implementing this trait in a breeding programme to select for E. coli F4ac-resistant animals. The selection of resistant pigs should start on the male side due to the inability of resistant sows to produce sufficient amounts of protecting antibodies in the colostrum. Selection of genetically F4ac-resistant pigs is a sustainable and suitable alternative to decreasing animal loss and antibiotic use due to diarrhoea.

Antigen-specific CD4+ and CD8+ T-cell responses in PBMC from pony mares immunized with either native or recombinant zona pellucida vaccines.

Few studies have investigated the cell mediated immune response during zona pellucida-based immunocontraception, despite hypothesized cytotoxic T-cell involvement in ovarian dysfunction associated with these vaccines. This study aimed to investigate antigen-specific anamnestic responses of helper (CD4+) and cytotoxic (CD8+) T-lymphocytes in peripheral blood mononuclear cells (PBMC) isolated from pony mares before and after their treatment with native porcine zona pellucida (pZP), recombinant pZP3 and pZP4 antigens (reZP) or adjuvanted saline. Mares were randomly assigned to pZP, reZP and control groups (n = 7 per group). Treatments consisted of a primary vaccination or saline (V1; Day 0) incorporating Freund's modified complete adjuvant, followed by a single booster (V2; Day 35) incorporating Freund's incomplete adjuvant. Peripheral blood mononuclear cells were isolated and cryopreserved immediately prior to V1 (Day 0) and five weeks post V2 (Day 70). Relative proliferation of T-lymphocytes in response to pZP antigen was assessed using carboxyfluorescein diacetate succinimidyl ester dilution with immunophenotyping, analysed via flow cytometry. Significant pZP-specific CD4+ and CD8+ T-lymphocyte responses were detected in PBMC isolated from mares treated with either pZP or reZP, in comparison to pre-treatment samples. In the pZP group, but not the reZP group, CD8+ T-cell proliferation showed significant negative correlations to circulating progesterone, oestradiol and anti-Müllerian hormone levels. Results suggest that antigen-specific CD8+ T-cells may play a role in ovarian suppression observed during pZP immunocontraception in this species.

Serum anti-Müllerian hormone dynamics in mares following immunocontraception with anti-zona pellucida or -GnRH vaccines.

Circulating anti-Müllerian hormone concentration (AMH) is positively correlated to the number of small growing follicles in the mare and may reflect ovarian function. Dynamics of AMH during immunocontraception have not previously been investigated. This study aimed to compare serum AMH in mares following treatment with native porcine zona pellucida (pZP), recombinant pZP3 and pZP4 (reZP) or gonadotrophin releasing hormone (GnRH) vaccines, and saline-treated controls. Stored sera collected during two previous studies examining ovarian activity in mares during zona pellucida (ZP) or GnRH immunocontraception were analysed for serum AMH. Data were compared among treatment groups using mixed-effects linear regression and one-way ANOVA with post hoc testing. Correlations between AMH and previously reported clinical variables were estimated using Spearman's rho. Mares immunized against GnRH showed variable but detectable AMH throughout successive breeding and non-breeding seasons that were not significantly different to unvaccinated control mares. Mares treated with pZP demonstrated marked, reversible suppression of AMH. Mares immunized using reZP showed an intermediate effect. In the ZP study, AMH was positively correlated to serum progesterone concentrations, mean ovarian volumes and antral follicle counts, whereas no correlations between AMH and serum progesterone concentrations, mean ovarian volumes, or the presence of one or more follicles ≥20 mm in diameter were detected in the GnRH study. In conclusion, marked suppression of AMH during pZP immunocontraception, but not during GnRH immunocontraception, suggested enhanced suppression of ovarian follicular development and, or follicular function during pZP immunocontraception. Serum AMH concentrations may provide a novel tool for the assessment of ovarian function during ZP-based immunocontraception.

Ovarian function and pregnancy outcome in pony mares following immunocontraception with native and recombinant porcine zona pellucida vaccines.

REASONS FOR PERFORMING STUDY: Few studies have investigated ovarian function in the mare undergoing porcine zona pellucida (pZP) immunocontraception despite reported ovarian dysfunction in other species. OBJECTIVES: This study aimed to describe ovarian function and oestrous cyclicity in pony mares following treatment with either the conventional pZP vaccine or a novel recombinant form of the vaccine derived from porcine ZP3 and ZP4 (reZP). In addition, the contraceptive efficacy of pZP vs. reZP was assessed. STUDY DESIGN: Blinded, randomised, prospective clinical trial. METHODS: Mares (n = 21) were randomised into 3 groups of 7: Group I received the pZP vaccine, with a booster 5 weeks later; Group II received the reZP vaccine, with a booster 5 weeks later; and Group III (controls) received 2 treatments, 5 weeks apart, of saline and adjuvant alone. Mares underwent weekly monitoring via transrectal palpation and ultrasound examination of the reproductive tract, with daily monitoring during oestrus. Data were collected over a 24 week period coinciding with the physiological breeding season; treatments commenced in Week 4. Serum samples were obtained for antibody titres and ovarian steroid level analyses at 7 day intervals. Cycling mares were bred via fresh semen artificial inseminations over a maximum of 2 consecutive oestrous cycles, commencing 5 weeks post booster vaccination. RESULTS: Control mares cycled throughout the trial. After treatment, 6 of 7 pZP mares (86%) and one reZP mare (14%) had an extended anoestrus that correlated with basal serum oestradiol and progesterone levels. All mares resumed cyclicity by 10 months post treatment. Pregnancies were diagnosed in all controls, 4 reZP- (57%) and none of the pZP-immunised mares. CONCLUSIONS: The current study demonstrates the reversible suppression of ovarian function in pony mares following treatment with pZP. The effect of the reZP vaccine on pregnancy outcome requires further investigation.

Fertility suppression of some wildlife species in southern Africa-a review.

Generally speaking, southern Africa's wildlife populations in small-to-medium-sized protected game reserves (10,000-65,000 ha) reproduce at rapid rates which often lead overpopulation of certain species. Most commonly these are large predators such as lions, African wild dogs and cheetahs, and elephants. Overpopulation of large predators leads to depletion of prey species, breakouts into neighbouring communities and increased risks for disease transmission. An overabundance of elephants leads to habitat destruction which is to the detriment of not only other herbivores but also certain bird species. By far, the most acceptable and effective method of population control is contraception. Another problem, particularly in South Africa, is the large numbers of large predators that are held in zoos, wildlife sanctuaries or captive breeding facilities. Once again, there is a need for contraception to control the rate of reproduction. In this review, we discuss the methods that have been most commonly used for some wildlife species in southern Africa. The methods include hormonal control and immunocontraception. We also address the problem of androgen-related aggressive behaviours in elephant bulls and giraffe males and present solutions that have been used to ameliorate such behaviours.

Standing sedation with medetomidine and butorphanol in captive African elephants (Loxodonta africana).

Doses for standing sedation allowing for various procedures in otherwise inaccessible, untrained captive African elephant bulls are presented. Thirty-three standing sedations were performed in 12 males aged 8-30 years (one to four sedations per animal). Each bull received a combination of 0.009 ± 0.002 mg/kg medetomidine and 0.03 ± 0.007 mg/kg butorphanol. Full sedation was reached on average 25.5 min after injection. The addition of hyaluronidase (1000-2000 IU) significantly reduced time to full sedation to 16.5 min (paired t test, P = 0.024). Reversal was induced with intramuscular atipamezole 0.008 (±0.002) and naltrexone 0.035 (±0.015) mg/kg. Recovery took on average 7 min (3-18 min). The medetomidine/butorphanol combination provided safe standing sedation for smaller procedures.

Inheritance of porcine receptors for enterotoxigenic Escherichia coli with fimbriae F4ad and their relation to other F4 receptors.

Enteric Escherichia coli infections are a highly relevant cause of disease and death in young pigs. Breeding genetically resistant pigs is an economical and sustainable method of prevention. Resistant pigs are protected against colonization of the intestine through the absence of receptors for the bacterial fimbriae, which mediate adhesion to the intestinal surface. The present work aimed at elucidation of the mode of inheritance of the F4ad receptor which according to former investigations appeared quite confusing. Intestines of 489 pigs of an experimental herd were examined by a microscopic adhesion test modified in such a manner that four small intestinal sites instead of one were tested for adhesion of the fimbrial variant F4ad. Segregation analysis revealed that the mixed inheritance model explained our data best. The heritability of the F4ad phenotype was estimated to be 0.7±0.1. There are no relations to the strong receptors for variants F4ab and F4ac. Targeted matings allowed the discrimination between two F4ad receptors, that is, a fully adhesive receptor (F4adRFA) expressed on all enterocytes and at all small intestinal sites, and a partially adhesive receptor (F4adRPA) variably expressed at different sites and often leading to partial bacterial adhesion. In pigs with both F4ad receptors, the F4adRPA receptor is masked by the F4adRFA. The hypothesis that F4adRFA must be encoded by at least two complementary or epistatic dominant genes is supported by the Hardy-Weinberg equilibrium statistics. The F4adRPA receptor is inherited as a monogenetic dominant trait. A comparable partially adhesive receptor for variant F4ab (F4abRPA) was also observed but the limited data did not allow a prediction of the mode of inheritance. Pigs were therefore classified into one of eight receptor phenotypes: A1 (F4abRFA/F4acR+/F4adRFA); A2 (F4abRFA/F4acR+/F4adRPA); B (F4abRFA/F4acR+/F4adR-); C1 (F4abRPA/F4acR-/F4adRFA); C2 (F4abRPA/F4acR-/F4adRPA); D1 (F4abR-/F4acR-/F4adRFA); D2 (F4abR-/F4acR-/F4adRPA); E (F4abR-/F4acR-/F4adR-).

Reversibility of the effects of GnRH-vaccination used to suppress reproductive function in mares.

REASONS FOR PERFORMING STUDY: Active immunisation against gonadotrophin-releasing hormone (GnRH) provides a reversible method for control of oestrous behaviour and fertility in mares. Previous reports failed to demonstrate the interval to resumption of cyclic ovarian activity after GnRH-vaccination. HYPOTHESIS: Administration of the GnRH-vaccine Improvac in a large group of mares of various ages will result in effective, reliably reversible suppression of ovarian activity within a 2 year period. METHODS: The mares, subdivided into 3 age categories, were vaccinated twice (with a 35 day interval) using 400 µg Improvac and monitored via blood samples until Day 720 after initial vaccination for serum progesterone concentration determination by radioimmune assay and anti-GnRH antibody titre by enzyme immunoassay. Samples were collected until individuals resumed cyclic ovarian activity. RESULTS: All mares showed suppression of cyclic ovarian activity by clinical examination and serum progesterone concentration (SPC) ≤ 1 nmol/l by Day 70 and 92.2% resumed cyclic activity by SPC at Day 720 with a mean interval = 417.8 days (s.d. ± 23.9; range 232-488 days, median 344 days). A significant age effect (P = 0.028) on the interval, but not on GnRH-antibody titre response, was observed between the youngest (≤ 4 years) and oldest (≥ 11 years) categories. CONCLUSIONS: Immunising adult mares of all ages with Improvac resulted in a reversible suppression of cyclic ovarian activity in most mares. An age effect, with the youngest mares showing a longer interval to reversibility, was observed.

Characterisation and validation of an enzyme-immunoassay for the non-invasive assessment of faecal glucocorticoid metabolites in cheetahs (Acinonyx jubatus).

The non-invasive measurement of adrenocortical function in cheetahs is an important tool to assess stress in captive and free-ranging individuals, because stress has been suggested to be one of the causes of poor reproductive performance of captive cheetahs. We tested four enzyme immunoassays (EIA) in two captive cheetahs in Germany using adrenocorticotropic hormone (ACTH) challenges and identified the corticosterone-3-CMO EIA to be most sensitive to the increase in faecal glucocorticoid metabolite (fGCM) concentrations after the ACTH challenge. This EIA performed also well in five captive cheetahs in South Africa. The fGCM concentrations across all seven cheetahs increased within 24h by 681% compared to the baseline levels prior to ACTH. Storage of faecal samples at 0-4°C did not strongly affect fGCM concentrations within 24h, simplifying sample collection when immediate storage at -20°C is not feasible. The two cheetahs in Germany also received an injection of [(3)H]cortisol to characterise fGCMs in faecal extracts using high-performance liquid chromatography (HPLC) immunograms. HPLC fractions were measured for their radioactivity and immunoreactive fGCM concentrations with the corticosterone-3-CMO EIA, respectively. The results revealed a polar peak of radiolabelled cortisol metabolites co-eluting with the major peak of immunoreactive fGCMs. Thus, our EIA measured substantial amounts of fGCMs corresponding to the radioactive peaks. The peaks were of higher polarity than native cortisol and corticosterone, suggesting that the metabolites were conjugated, which was confirmed by solvolysis of the HPLC fractions. Our results show that the corticosterone-3-CMO EIA is a reliable tool to assess fGCMs in cheetahs.

Reproduction in the endangered African wild dog: basic physiology, reproductive suppression and possible benefits of artificial insemination.

The African wild dog (Lycaon pictus) is an endangered exotic canid with less than 5500 animals remaining in the wild. Despite numerous strategies to conserve this species, numbers of free-living animals are in decline. It is a highly social species with a complex pack structure: separate male and female dominant hierarchies with, typically, participation of subdominant adults in the rearing of the dominant breeding pairs' pups. Basic reproductive knowledge is largely missing in this species, with only limited information available on the profile of reproductive hormones, based on non-invasive endocrine monitoring. The dominant or alpha male and female are reproductively active and the subdominants are generally reproductively suppressed. However, the occasional production of litters by subdominant females and evidence of multiple paternity within litters suggests that fertility of subordinates is not completely inhibited. In this respect, there are still considerable gaps in our knowledge about the mechanisms governing reproduction and reproductive suppression in African wild dogs, particularly the influence of dominance and pack structure on both male and female fertility. Given concerns over the long-term survival of this species, further research in this area is essential to provide valuable information for their captive breeding and conservation. Reproductive information can also be applied to the development of Assisted Reproductive Techniques for this species; the utility of which in African wild dog conservation is also discussed.

Fecal 20-oxo-pregnane concentrations in free-ranging African elephants (Loxodonta africana) treated with porcine zona pellucida vaccine.

Because of overpopulation of African elephants in South Africa and the consequent threat to biodiversity, the need for a method of population control has become evident. In this regard, the potential use of the porcine zona pellucida (pZP) vaccine as an effective means for population control is explored. While potential effects of pZP treatment on social behavior of African elephants have been investigated, no examination of the influence of pZP vaccination on the endocrine correlates in treated females has been undertaken. In this study, ovarian activity of free-ranging, pZP-treated African elephant females was monitored noninvasively for 1 yr at Thornybush Private Nature Reserve, South Africa, by measuring fecal 5α-pregnan-3ß-ol-20-on concentrations via enzyme immunoassay. A total of 719 fecal samples from 19 individuals were collected over the study period, averaging 38 samples collected per individual (minimum, maximum: 16, 52). Simultaneously, behavioral observations were made to record the occurrence of estrous behavior for comparison. Each elephant under study showed 5α-pregnan-3ß-ol-20-on concentrations rising above baseline at some period during the study indicating luteal activity. Average 5α-pregnan-3ß-ol-20-on concentrations were 1.61 ± 0.46 µg/g (mean ± SD). Within sampled females, 42.9% exhibited estrous cycles within the range reported for captive African elephants, 14.3% had irregular cycles, and 42.9% did not appear to be cycling. Average estrous cycle duration was 14.72 ± 0.85 wk. Estrous behavior coincided with the onset of the luteal phase and a subsequent rise in 5α-pregnan-3ß-ol-20-on concentrations. Average 5α-pregnan-3ß-ol-20-on levels positively correlated with rainfall. No association between average individual 5α-pregnan-3ß-ol-20-on concentrations or cyclicity status with age or parity were detected. Earlier determination of efficacy was established via fecal hormone analysis with no pregnancies determined 22 mo post-treatment and onward. Results indicate the presence of ovarian activity amongst pZP-treated female African elephants in 2 yr after initial immunization. Further study should now be aimed toward investigating the long-term effects of pZP vaccination on the reproductive function of female African elephants.

Effect of diet on the incidence of and mortality owing to gastritis and renal disease in captive cheetahs (Acinonyx jubatus) in South Africa.

Seventy-two adult cheetahs were evaluated for the degree of gastritis by endoscopic biopsy and for renal disease by serum creatinine. Cheetahs free of Grade 3 gastritis and renal disease were placed on Trial A; remaining cheetahs were placed on Trial B, which ran concurrently. All cheetahs were monitored for 4 years. Cheetahs exited Trial A and entered Trial B if they developed Grade 3 gastritis or renal disease. Cheetahs exited Trial B if they developed clinical gastritis or renal disease that required a dietary change or aggressive medical therapy or died owing to either disease. Cheetahs on Trial A were fed either a supplemented meat diet (N = 26) or commercial cat food (N = 22). Cheetahs on Trial B were fed either the same meat diet (N = 28) or a commercial dry cat food formulated for renal disease (N = 16). Cheetahs fed meat on Trial A had a daily hazard of developing Grade 3 gastritis 2.21 times higher (95% CI 0.95-5.15) than cheetahs fed commercial cat food. This hazard was not statistically significant (P = 0.07). Mean gastritis scores were not significantly different between the two groups. Cheetahs fed commercial cat food in both Trials had lower serum urea levels and higher creatinine levels than those fed meat. Evidence for the effect of diet in cheetahs with gastritis and/or renal disease (Trial B) was inconclusive. The number of cheetahs dying of gastritis or renal disease at the facility has dropped markedly since the study began. These results indicate that diet may play an important role in the incidence of Grade 3 gastritis and that dietary and/or therapeutic management of gastritis may reduce mortality owing to gastritis and renal disease in captive cheetahs.

Non-invasive monitoring of glucocorticoid metabolites in brown hyaena (Hyaena brunnea) feces.

The brown hyaena (Hyaena brunnea) is the least known of the large predators of southern Africa. The current IUCN status of the brown hyaena is "Near Threatened", and there are conservation concerns related to a general lack of biological knowledge of the species. For instance, a better knowledge of the responses to environmental and social stressors would improve our abilities to sustainably manage brown hyaena populations in both captive and free-ranging environments. We conducted adrenocorticotrophic hormone (ACTH) challenges in one female and one male adult brown hyaena at Lion Park Zoo, South Africa, to validate measurements of glucocorticoid metabolites (GCM) in brown hyaena feces via an enzyme immunoassay (EIA). We also measured gastrointestinal transit times (GIT times) and the GCM degradation in feces left in ambient temperature for up to 32 hr to more reliably assess the use of this assay as a tool for non-invasive glucocorticoid measurements. Intramuscular injections of synthetic ACTH yielded GCM levels of 388% (female) and 2,682% (male) above baseline with peak increases occurring 25- to 40-hr after injection. The time delay of fecal GCM excretion approximately corresponded with food transit time in the brown hyaenas. Fecal GCM levels declined significantly over time since defecation. Our results provided a good validation that fecal GCMs accurately reflect circulating glucocorticoid stress hormones in brown hyaenas, but we highlight that samples have to be frozen immediately after defecation to avoid bias in the measurements as a result of bacterial degredation.

Vaccination against GnRH may suppress aggressive behaviour and musth in African elephant (Loxodonta africana) bulls--a pilot study.

Aggressive behaviour and musth are constant problems in captive and sometimes in free-ranging African elephant bulls. Aggressive bulls are difficult and musth bulls almost impossible to manage without severely restricting their movement either by leg-chaining or using tranquillisers. This study investigated the relationship between faecal androgen metabolites (FAM) and faecal cortisol metabolites (FCM) concentrations and aggressive behaviour and tested a GnRH vaccine as a means of down-regulating aggressive behaviour and musth in 1 free-ranging and 5 captive elephant bulls. The bulls were non-aggressive (n=3), aggressive (n=2) or in musth (n=1) at the onset of the study. The bulls were injected with a GnRH vaccine-adjuvant combination 3 or 4 times at 3- to 7-week intervals. Behaviour, FAM and FCM concentrations were measured during every week prior to vaccination until 4 months after the last vaccination. FAM concentrations were positively correlated with aggressive behaviour before the 1st vaccination. Androgen production, as reflected by FAM concentrations, was down-regulated in 3 of the 6 immunised bulls. At least 2 bulls and possibly a 3rd showed behavioural improvement following GnRH vaccination and in all 3 temporal gland secretion ceased. No further aggressive behaviour was observed until the end of the study in any of the bulls. The results of this 1st GnRH immunisation study suggest that it could be a useful method to control aggressive behaviour and musth in African elephant bulls.

Refined localization of the Escherichia coli F4ab/F4ac receptor locus on pig chromosome 13.

Diarrhoea in newborn and weaned pigs caused by enterotoxigenic Escherichia coli (ETEC) expressing F4 fimbriae leads to considerable losses in pig production. In this study, we refined the mapping of the receptor locus for ETEC F4ab/F4ac adhesion (F4bcR) by joint analysis of Nordic and Swiss data. A total of 236 pigs from a Nordic experimental herd, 331 pigs from a Swiss experimental herd and 143 pigs from the Swiss performing station were used for linkage analysis. Genotyping data of six known microsatellite markers, two newly developed markers (MUC4gt and HSA125gt) and an intronic SNP in MUC4 (MUC4-8227) were used to create the linkage map. The region for F4bcR was refined to the interval SW207-S0075 on pig chromosome 13. The most probable position of F4bcR was in the SW207-MUC4 region. The order of six markers was supported by physical mapping on the BAC fingerprint contig from the Wellcome Trust Sanger Institute. Thus, the region for F4bcR could be reduced from 26 to 14 Mb.

Captive breeding of cheetahs in South Africa--30 years of data from the de Wildt Cheetah and Wildlife Centre.

The de Wildt Cheetah and Wildlife Centre was established in 1971 and the first cheetah cubs were born in 1975. During the period 1975-2005, 242 litters were born with a total of 785 cubs. Mean cub survival from 1 to 12 months and greater than 12 months of age was 71.3 and 66.2%, respectively. The majority of losses (84.9%) occurred during the first month postpartum whereas only 15.1% deaths took place between 1 and 12 months of age. Females were first bred at an age of approximately 3 years, reached maximum reproductive age at 6-8 years, where after fertility declined. Males reached peak reproduction at 6 and maintained this for up to 12 years of age. Male fertility was best correlated with sperm morphology. During recent years, for practical purposes, males were allocated to 'good' (>or=70% normal), 'fair' (40-70% normal) and 'poor' (<40% normal) categories according to sperm morphology count. The breeding males were selected from the good (preferably) and fair categories but poor category males were also used at times. Average litter sizes for 'good', 'fair' and 'poor' males were 3.44 (n = 21), 3.14 (n = 18) and 2.28 (n = 18), respectively. In females the heritability for litter size was high at 0.5848 (532 progeny, 1975-2007) and the maternal heritability for cub mortality was estimated to be 0.596. The data from the de Wildt Cheetah and Wildlife Centre and two other centres in the world (Kapama and Wassenaar) demonstrate that cheetah can be bred successfully in captivity.

Bull breeding soundness evaluation in Southern Africa.

The motivation for and process leading up to the publication of a new bull breeding soundness certification standard endorsed by the South African Veterinary Association is described. The veterinary certificate of bull breeding soundness and explanatory notes and minimum standards are shown. The first component of the certificate is a declaration by the veterinarian that the bull complies with the minimum standards set for examinations for the selected purpose, these being for use as a natural service sire, as a donor of semen for distribution, and for insurance purposes. This is followed by the details of the bull and owner, and a list of the recommended examinations and tests for the bull with provision for which were performed. Certificates are available in book form with the explanatory notes and minimum standards on the reverse, and a carbon copy which remains in the book. The clarity and ease of completion of the document are regarded as being positive features. Bulls are either classified as breeding sound or not, with no actual parameters indicated on the document and no certificate issued for those which do not meet the set criteria. Contact details of the parties involved are shown on the certificate to allow for communication as a means of avoiding disputes.

Implementing immunocontraception in free-ranging African elephants at Makalali conservancy.

The goal of programmes to provide contraception for elephants should be to formulate an approach that does not require the relocation or immobilisation of the same individual year after year, which would be long-lasting and cause minimal disruption to social and reproductive behaviour. The programmes should be simple to administer, safe and cost-effective, and must meet the objectives defined by managers in the field. An immunocontraceptive programme was initiated in a small free-roaming population of elephants at the Greater Makalali Private Game Reserve in Limpopo Province in 2000 to determine whether the porcine zona pellucida (pZP) vaccine can successfully control population sizes. Further objectives were to determine implementation costs and efficiency through a multi-faceted approach. We have demonstrated that immunocontraception meets the objectives set by managers in the field. Minimal social disruption was observed over the course of treatment, with the mode of delivery (ground or aerial vaccinations) determining the degree of stress within herds and speed of resumption of normal movement patterns. Aerial vaccinations resulted in the least disturbance, with target herds being approachable within a day. In 2005, implementation costs were R880-R1000/elephant/year, inclusive of darts, vaccine, helicopter and veterinary assistance. Irrespective of the source or method of vaccine delivery, a non-pregnant elephant is rendered infertile from 1st vaccine administration. The sooner immunocontraception is implemented, the sooner population growth rates can be controlled. pZP contraception is a realistic alternative management tool, particularly if used as part of a long-term management strategy. Mass-darting from the air eliminates the need for detailed individual histories of each elephant or for employing a person to monitor elephants. Thus, implementation of immunocontraception in larger populations is feasible and practical.

Prevalence and body distribution of sarcoids in South African Cape mountain zebra (Equus zebra zebra).

There are no reports in the literature describing any tumours, and specifically sarcoids, in zebras. The equine sarcoid, a locally aggressive, fibroblastic skin tumour, is the most common dermatological neoplasm reported in horses. The Cape mountain zebra (CMZ) has been described as one of the most vulnerable mammals in South Africa with current populations existing in isolated units. All South African CMZ are descendants from no more than 30 individual animals originating from 3 populations, namely the Mountain Zebra National Park, and Kammanassie and Gamka Mountain Nature Reserves near Cradock. The possibility therefore exists that the existing populations arose from a very small gene pool and that they are considerably inbred. A reduction in major histocompatibility complex diversity due to genetic bottlenecks and subsequent inbreeding probably contributed to uniform population sensitivity and the subsequent development of sarcoid in two CMZ populations, namely in the Bontebok National Park and Gariep Nature Reserve. The entire population of CMZ in the Bontebok National Park was observed and sampled during 2002 to document the prevalence and body distribution of sarcoids. During the same year, a comparative study was carried out on an outbred population of Burchell's zebra in the Kruger National Park. The prevalence in CMZ in the Bontebok National Park was 53 %, while the Burchell's zebra in Kruger National Park had a prevalence of 1.9 %. The most common sites for sarcoid in CMZ were the ventral abdomen and limbs. Prevalence of sarcoids in horses recorded in the literature varies between 0.5 % and 2 %. The Gariep Nature Reserve recently reported a prevalence of almost 25 % in CMZ in the reserve.

The use of a probiotic in captive cheetahs (Acinonyx jubatus).

Juvenile captive cheetahs (Acinonyx jubatus) often present with diarrhoea that is commonly associated with bacterial infections. A species-specific probiotic containing Lactobacillus Group 2 and Enterococcus faecium was prepared from healthy adult cheetahs. Juvenile cheetahs (n = 27) between 8 and 13 months of age were included in the probiotic trial. The animals were observed prior to and after feeding of the probiotic which was made available for 28 days. Feeding of the probiotic resulted in a significantly increased body weight in the treatment group (P = 0.026), while there was no increase in the control group. A relative improvement in the faecal quality in the probiotic group during the treatment period compared with the pre-treatment (P = 0.0363) and post-treatment (P = 0.004) period was observed. This was accompanied by an absence of blood and mucus in the faeces during the treatment period in the probiotic group.