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The behaviour of mares is often detrimental to their performance resulting in frequent demand for methods to suppress gonadal function. In addition, prevention of unintended reproduction especially in feral horse populations may require methods for suppression of gonadal function. Surgical ovariectomy is a safe method but not an acceptable approach in feral mares and undesired in mares where future breeding is considered. There are different approaches for artificial prolongation of the luteal phase resulting in transient inhibition of oestrus and ovulation. Among those, treatment with natural or synthetic progestogens is considered the most common and successful method. Whereas application of intrauterine devices may result in prolongation of luteal function in non-pregnant mares, intrauterine insertion of glass balls is no longer recommended because of complications in individual mares. There are several safer alternatives that may be of interest, especially for population control in free-roaming horses. Treatment with long-acting deslorelin implants inhibited ovulation and oestrus behaviour in mares for limited and variable time intervals in a dose-dependent manner. The effect of GnRH vaccines varies considerably among individual mares, is age dependent, and oestrus-like behaviour may still occur. Contraception via immunization against native porcine or recombinant zona pellucida antigen is successful, but immunocontraception is as much a result of ovarian inactivity as an antibody-based block to sperm-oocyte binding. In conclusion, several treatments for suppression of gonadal function in mares are available, but there are advantages and disadvantages associated that have to be considered. The treatment of choice will thus differ with regard to the demands.

Giraffe present unique contraception challenges as males persistently pursue females during estrus. Year-round pursuit during frequent recurring estrus can pose significant risk under slippery conditions. Complete ovarian suppression is a useful tool in giraffe because it eliminates estrous behavior, interest from the male, and controls reproduction. Effective reproduction control in giraffes has been achieved with porcine zona pellucida, oral melengestrol acetate, and depot medroxy-progesterone acetate. However, these methods allow some degree of folliculogenesis and estrous behavior. Improvest® is a gonadotropin releasing hormone (GnRH) immunological product that elicits antibodies against GnRH and abrogates the effects of endogenous GnRH. This study evaluated the efficacy of Improvest® for gonadal suppression in seven females and one male giraffe by monitoring steroid hormones. Seven female giraffe were treated intramuscularly with an initial dose, a booster at 4 weeks and maintenance boosters at 3-month intervals (600 µg/dose) for 12 months. Six females were on supplemental contraception during the induction phase because separation from males was not possible. In the male (treated with 400 µg), testosterone concentrations decreased after the second injection. However, even with low serum testosterone concentrations, mounting (of nontreated females) behavior was still observed occasionally. Ovarian activity was suppressed in all treated females and interest by the males stopped; supplemental contraceptives (during the induction phase) did not impede the effect of Improvest®. After 15.3 months (seven doses), Improvest® was discontinued in three females which no longer needed contraception. In these females, ovarian activity was noted approximately 90 days after the last dose.

The aim of this study was to develop protocols for contraception in both sexes of giraffes (Giraffa camelopardalis) by using the GnRH vaccine Improvac®. We evaluated the success of immunization by analyzing fecal reproductive hormone metabolites in female (n = 20) and male (n = 9) giraffes. Endocrine analysis provided the basis for the successful immunization protocol, as well as for assessing long-term effects. Reliable reduction of fecal steroid metabolites to baseline levels in female giraffes was achieved with three, and in males with four or five injections at 4-week intervals. Effective booster injections were administered at 2-month intervals in the first year of treatment and at three to 4-month intervals in the following years. In addition to endocrine analysis, we determined vaccination efficacy in bulls by assessing testicular atrophy. Long-term (>2 years) use in females was often accompanied by prolonged periods of persistent corpus luteum activity, although normal cycles were not observed. Problems might occur with reversibility, because in a few males and females, even after more than 2 years since treatment had been stopped, fecal hormone metabolites have not returned to pretreatment levels. The results are somewhat ambiguous, as reproduction can be suppressed by use of Improvac®, but the question of reversibility remains unsolved.

Background Gonadotropin‐releasing hormone (GnRH) plays a pivotal role in regulating the reproductive endocrine system. Objective An immunocontraception vaccine aimed at inhibiting the functions of GnRH is tested as a potential tool for controlling animal populations. Methods We developed a recombinant immunocontraceptive vaccine composed of GnRH‐I and GnRH‐II (GnRH I+II), which was conjugated with Salmonella typhimurium flagellin. Forty‐eight BALB/c mice aged 4 weeks were divided into four groups (each group had n = 12): non‐vaccinated male (NVM), non‐vaccinated female (NVF), vaccinated male (VM), and vaccinated female (VF). Mice in the vaccinated groups were vaccinated twice by intramuscular injection at 0 and 2 weeks with 300 μg of the recombinant GnRH protein complex per mouse. Mice in the non‐vaccinated groups were injected with saline and served as the unimmunized controls. Twenty‐four pairs of male and female mice were mated for 10–12 weeks after initial immunization in four groups: 6 NVF × 6 NVM, 6 VF × 6 NVM, 6 NVF × 6 VM, and 6 VF × 6 VM. Results: An increase (p, We developed a new form of immunocontraceptive vaccine composed of GnRH‐I and ‐II complex conjugated with STF‐2. We provide the vaccine efficacies with higher anti‐GnRH antibodies in mice. The vaccine containing the GnRH‐I + II peptide linked to STF‐2 induced the suppression of fertility by inhibiting testicular and ovarian functions and reducing sex hormone levels in both male and female mice. In addition, the effects of fertility reduction were confirmed through mating experiments .

Increasing human-wildlife conflicts worldwide are driving the need for multiple solutions to reducing “problem” wildlife and their impacts. Fertility control is advocated as a non-lethal tool to manage free-living wildlife and in particular to control iconic species. Injectable immunocontraceptives, such as GonaCon, stimulate the immune system to produce antibodies against the gonadotrophin-releasing hormone (GnRH), which in turn affects the release of reproductive hormones in mammals. Feral cattle (Bos indicus or Bos taurus) in Hong Kong are an iconic species whose numbers and impacts on human activities have increased over the last decade. Previous studies have proven that a primer vaccination and booster dose of GonaCon in female cattle are safe and effective in reducing pregnancy levels one year post-treatment. The aims of this project were 1. to evaluate the longevity of the effect of GonaCon in feral cattle up to four years post-vaccination; and 2. to assess if a second booster dose of GonaCon, administered at either two or four years post-vaccination, extends the contraceptive effect in this species. Vaccination with GonaCon, administered as a primer and booster dose, was effective in causing significant infertility in free-living cattle for at least three years post-vaccination, with the percentage of pregnant animals in the vaccinated group decreasing from 76% at vaccination to 35%, 19% and 7% in years 2, 3 and 4 post-vaccination, compared with 67% at vaccination to 50%, 57% and 14% respectively in the control group. A second booster dose of GonaCon administered either 2 or 4 years after vaccination rendered 100% of the Treated cattle infertile for at least another year. These results suggested that vaccination with GonaCon can reduce feral cattle population growth and that a second booster dose can extend the longevity of the contraceptive effect.

Male infertility or subfertility is frequently associated with disruption of the hypothalamic-pituitary-testis axis events, like secondary hypogonadism. However, little is known how this condition affects the proteomic composition of the epididymal fluid. In the present study, we evaluated the proteomic changes in the cauda epididymal fluid (CEF) in a swine model of secondary hypogonadism induced by anti-GnRH immunization using multidimensional protein identification technology. Seven hundred and eighteen proteins were identified in both GnRH-immunized and control groups. GnRH immunization doubled the number of proteins in the CEF, with 417 proteins being found exclusively in samples from GnRH-immunized boars. CEF from GnRH-immunized boars presented an increase in the number of proteins related to cellular and metabolic processes, with affinity to organic cyclic compounds, small molecules, and heterocyclic compounds, as well changed the enzymatic profile of the CEF. Also, a significant increase in the number of proteins associated to the ubiquitin-proteasome system was identified in CEF from GnRH-immunized animals. These results bring strong evidence of the impact of secondary hypogonadism on the epididymal environment, which is responsible for sperm maturation and storage prior ejaculation. Finally, the differently expressed proteins in the CEF are putative seminal biomarkers for testicular and epididymal disorders caused by secondary hypogonadism.

Background Approximately 40% of human pregnancies are unintended, indicating a need for more acceptable effective contraception methods. New antibody production systems make it possible to manufacture reagent-grade human monoclonal antibodies (mAbs) for clinical use. We used the Nicotiana platform to produce a human antisperm mAb and tested its efficacy for on-demand topical contraception. Methods Heavy and light chain variable region DNA sequences of a human IgM antisperm antibody derived from an infertile woman were inserted with human IgG1 constant region sequences into an agrobacterium and transfected into Nicotiana benthamiana. The product, an IgG1 mAb [“Human Contraception Antibody” (HCA)], was purified on Protein A columns, and QC was performed using the LabChip GXII Touch protein characterization system and SEC-HPLC. HCA was tested for antigen specificity by immunofluorescence and western blot assays, antisperm activity by sperm agglutination and complement dependent sperm immobilization assays, and safety in a human vaginal tissue (EpiVaginal™) model. Findings HCA was obtained at concentrations ranging from 0.4 to 4 mg/ml and consisted of > 90% IgG monomers. The mAb specifically reacted with a glycan epitope on CD52g, a glycoprotein produced in the male reproductive tract and found in abundance on sperm. HCA potently agglutinated sperm under a variety of relevant physiological conditions at concentrations ≥ 6.25 µg/ml, and mediated complement-dependent sperm immobilization at concentrations ≥ 1 µg/ml. HCA and its immune complexes did not induce inflammation in EpiVaginal™ tissue. Interpretation HCA, an IgG1 mAb with potent sperm agglutination and immobilization activity and a good safety profile, is a promising candidate for female contraception. Funding This research was supported by grants R01 HD095630 and P50HD096957 from the National Institutes of Health.

A sequence of studies is reviewed that reported the domestic horse (Equus caballus) mare as an appropriate and accessible research platform for recording clinical and laboratory data post-immunisation with anti- GnRH and -zona pellucida (ZP) immunocontraceptive vaccines. Experience with a native porcine ZP (pZP) vaccine in African elephant (Loxodonta africana) cows highlighted needs for improving vaccine formulations and more clearly defining associated ovarian effects and safety profiles. Initially, the efficacy, reversibility and safety of the GnRH vaccine Improvac® in mares was demonstrated using reproductive tract ultrasonography and concurrently measuring serum antibody titres and progesterone concentrations. Results informed the study design and minimally invasive monitoring of post-treatment ovarian steroid responses of this vaccine in free-ranging African elephant cows. A subsequent sequence of studies reported reversible contraceptive and immunological efficacy in pony mares immunised with pZP formulated with Freund's adjuvants. By comparison, mares treated with a recombinant ZP3 and ZP4 (reZP) vaccine showed disappointing responses. Unexpectedly, most pZP-treated mares showed ovarian inactivity. In attempting to understand this response, results showed the involvement of cytotoxic (CD8+) T-cells negatively correlated to serum ovarian steroid and anti-Mullerian hormone (AMH) levels. Of concern was the prevalence of injection-site lesions ascribable to Freund's adjuvants. Following this, mares treated with both pZP and a novel reZP vaccine formulated with non-Freund's adjuvants showed comparable immunological responses and ovarian inactivity, notably without adverse treatment reactions. In addition, measuring AMH showed promise for monitoring ovarian function in anti-ZP-treated animals.

The small Indian mongoose (Herpestes auropunctatus) was introduced to Japanese islands and has impacted on the island’s biodiversity. Population control has been attempted through capturing but its efficiency has rapidly declined. Therefore, new additional control methods are required. Our focus has been on the immunocontraceptive vaccines, which act in an especially species-specific manner. The amino-acid sequence of the mongoose ovum zona pellucida protein 3 (ZP3) was decoded and two types of synthetic peptides (A and B) were produced. In this study, these peptides were administered to mongooses (each n=3) and the sera were collected to verify immunogenicity using ELISA and IHC. Treated mongoose sera showed an increasing of antibody titer according to immunizations and the antigen-antibody reactions against the endogenous mongoose ZP. In addition, IHC revealed that immune sera absorbed with each peptide showed a marked reduction in reactivity, which indicated the specificity of induced antibodies. These reactions were marked in peptide A treated mongoose sera, and the antibody titer of one of them lasted for at least 21 weeks. These results indicated that peptide A was a potential antigen, inducing autoantibody generation. Moreover, immunized rabbit antibodies recognized mongoose ZP species-specifically. However, the induction of robust immune memory was not observed. Also, the actual sterility effects of peptides remain unknown, it should be verified as a next step. In any case, this study verified synthetic peptides we developed are useful as the antigen candidates for immunocontraception of mongooses.

SpayVac® is an immunocontraceptive vaccine based on porcine zona pellucida (pZP) antigens and uses a patented liposome formulation (VacciMax™ or DepoVax®). It has delivered single-dose, long-lasting (4–10 years) immunocontraception in several species. Previous studies have demonstrated a positive correlation between levels of pZP antibodies produced and contraceptive effect; however, individual mares that were consistently infertile did not necessarily have the highest antibody titers. The objective of this study was to identify potential differences in specific immunoglobulin G (IgG) isotype responses among mares treated with SpayVac (VacciMax formulation) to improve our understanding of vaccine efficacy and potential management applications. We analyzed serum samples collected 1, 2 and 4 years post-vaccination from mares in another study that were continuously infertile or had foaled at least once during the 4-year period (n = 14 each). Additional samples from the continuously infertile mares were collected 5 years post-vaccination. A fluorescent bead-based assay was used to distinguish IgG isotype responses against pZP. IgG1 antibodies were generally higher in the infertile compared to the fertile mares, but only IgG4/7 antibodies were significantly higher in infertile mares during years 1 and 2 post-vaccination (p

Human-wildlife conflicts are increasing worldwide. For instance, growing numbers of free-roaming feral cattle in Hong Kong are causing traffic accidents and damaging crops. Public antipathy towards lethal methods to manage wildlife has promoted research into alternative options, such as fertility control. The aims of this study were to assess the potential side effects and effectiveness of the injectable immunocontraceptive vaccine GonaCon on free-roaming feral cattle in Hong Kong. Sixty female cattle were captured and randomly assigned to treatment or control groups. Treatment animals were administered one dose of GonaCon, followed by a booster dose 3–6 months later. Control animals were administered an equivalent dose of a saline solution. The side effects of GonaCon were assessed by monitoring injection site, body condition and body weight at vaccination, at the booster stage and one year after initial vaccination. At the same times, blood samples were collected to quantify antibodies to the vaccine and to assess pregnancy status. GonaCon did not affect the body weight or body condition of cattle and had no adverse side effects such as injection site reactions, limping or abnormal behaviour. GonaCon did not appear to interrupt ongoing pregnancies but reduced fertility significantly: the proportion of pregnant animals in the GonaCon-treated group decreased from 76% at initial vaccination to 6% one year after vaccination, compared to 67% and 57% respectively in the control group. There was no difference between antibody titres at the booster stage or one year post vaccination, suggesting the booster dose maintained antibody levels. This study confirmed that GonaCon is safe and effective in inducing infertility in feral cattle, with a booster dose critical for maintaining infertility.

The aim of this study was to assess the effect of immune-spaying on sensory characteristics and the volatile organic compound (VOC) profile of dry-cured shoulders and loins by comparing Iberian × Duroc surgically spayed females, immune-spayed females and entire females. VOC profile of dry-cured shoulders was not significantly affected by the reproductive status, probably due to the large heterogeneity of dry-cured shoulders as a product. Correspondingly, dry-cured shoulders showed little differences among treatment groups, with better scores for marbling, hardness and chewiness attributes in the immune-spayed females. Dry-cured loin sensory traits such as brightness, marbling, chewiness and juiciness, presented better scores in immune-spayed females. Moreover, dry-cured loins showed a higher homogeneity that allowed the effects of spaying to be observed, thus the Principal Component Analysis performed on VOC profile data indicated a better separation of samples among treatment groups. Consequently, immune-spaying could be a viable alternative to surgical spaying from the point of view of meat quality.

Feral and semi-feral donkeys are recognised as a problem in some world regions. The main problem associated with uncontrolled donkey populations is habitat degradation and competition for feed resources, especially in arid climes. Controlling population numbers would reduce the impact of donkeys and other species. While removal by various means is effective, it has been shown to stimulate reproductive rate. Probably the most effective and humane solution is reducing reproduction using minimally invasive methods including immunocontraception. This study tested the immunocontraceptive efficacy and safety of zona pellucida (ZP) vaccines, both recombinant (reZP; three treatments) and native porcine (pZP; two treatments) vaccines formulated with Freund’s modified complete (primary) and Freund’s incomplete (boosters) adjuvants in donkey jennies. Control jennies received adjuvants only (two treatments). Twenty-five non-pregnant jennies were randomly assigned to reZP (n = 9), pZP (n = 8) or control (n = 8) groups. Weekly monitoring of the reproductive tract and ovaries via transrectal palpation and ultrasound and inspection of injection sites was conducted and anti-pZP antibody titers were measured. Five weeks after last treatment, one donkey jack was introduced to each group and rotated every 21 days. By 232 days after last treatment the number pregnant and median days to pregnancy was 2/9 and 214 (reZP group), 1/8 and 196 (pZP group) and 8/8 and 77 (control group). Median time to ovarian shut-down was 77 (9/9) and 56 (7/8) days for reZP and pZP groups, respectively. This was observed in association with a distinct reduction in mean uterine diameter. The antibody response was equally good for both ZP-treated groups. Incorporation of Freund’s adjuvants initially produced a high incidence of side effects from local swelling and intermittent lameness followed weeks later by sterile abscesses (reZP, 9/9; pZP, 7/8; control, 3/8). Both ZP vaccines effectively controlled reproduction in jennies, albeit with a high incidence of adjuvant-associated side effects.

This study aimed to analyze the effect and mechanism of immunization of oral

There is a need for permanent, non-surgical methods of contraception for many animal species. Here we discuss the hypothesis that transgene-mediated expression of fertility inhibiting molecules such as monoclonal antibodies, ligands for cell surface receptors, receptor decoys, or small RNAs can provide such a method, which we term vectored contraception. We outline the technologies involved, progress made, and discuss challenges to implementation.

Contraceptive vaccine (CV) is a valuable, non-invasive, and alternative method for purposeful contraception. Sperm antigens are useful targets for producing CVs due to their specialized expression in sperm. In this study, a recombinant protein containing three main sperm epitopes (IZUMO1, SACA3, and PH-20) was designed and evaluated as CV to control fertility in male mice. The chimeric recombinant protein was expressed and purified in E. coli. Male mice were immunized by 100 μg purified protein and sera were collected to assess IgG antibodies. Evaluating the reproductive performance, immunized male mice mated with normal-fertile female mice and mating rate and the number of newborns was studied. Immunized mice were sacrificed and necropsy and histopathology studies were conducted. The results revealed that the designed chimeric protein stimulated the immune system of the mice effectively. The level of IgG antibody was significantly higher in vaccinated mouse rather than control mouse. Eighty percent of the vaccinated mice became infertile and in the remaining ones, the number of children decreased to 4-6 offspring instead of 10-12 in normal mice. Histopathological studies showed that no organs including heart, brain, lung, liver, kidney and intestine were damaged. However, Normal spermatogenesis has been disrupted and necrotic spermatogonia cells were reported in Seminiferous tubules. We concluded that the designed chimeric protein containing IZUMO1, SACA3, and PH-20 epitopes can stimulate the immune system and cause male contraception without any side effects.

HLA-G is a nonclassical HLA immunotolerogenic molecule expressed in different human cell types. Successful embryo implantation is a consequence of information exchange between the uterus and the blastocyst. It is widely accepted that HLA-G expression by the fetus promotes the establishment of several mechanisms that, ultimately, would protect the developing embryo from maternal immune rejection and seems to be essential to both an adequate implantation and a healthy pregnancy. MicroRNAs miR-148a and miR-152 down-regulate HLA-G expression. The levels of both microRNAs in the placenta are very low. Although various contraceptive methods are available in the market, several of the most popular are based on hormone administration, an approach that have been causing concerns regarding their adverse effects. This scenario has led the research and development of new contraceptive methods meant to induce low disturbances in women body. Based on this context, we hypothesize that the delivery of miR-148a and miR-152 microRNAs, carried by liposomes, into the uterus, would locally induce a down-regulation of the immunotolerogenic HLA-G molecule. In this sense, a local concentration increase of both miR-148a and miR-152 would counteract HLA-G expression and therefore prevent pregnancy development, being a potential tool for the development of a new contraceptive therapy.

To minimize human-animal conflicts for habitation and burden of zoonotic diseases, it is imperative to develop new strategies for wildlife population management. In this direction, contraceptive vaccines eliciting immune response against hormones/proteins critical for reproduction have emerged as one of the promising options. Contraceptive vaccines based on neutralization of gonadotropin releasing hormone (GnRH) have been used for inhibition of fertility in various species such as wild horses, white-tailed deer, pigs, cats, dogs etc. It has been used for immunocastration of male pigs to improve meat quality. However, additional safety studies of GnRH vaccine will be needed in light of presence of its receptor at extra-pituitary sites. Native porcine zona pellucida (PZP)-based contraceptive vaccines have shown their utility in the management of the population of both captive and free-ranging wild horses and white-tailed deer. Long-term use of the PZP-based contraceptive vaccines has also demonstrated their safety. Ideally single injection of the contraceptive vaccine should elicit long lasting immune response and desired contraceptive efficacy, which will require development of novel vaccine delivery platforms and more potent adjuvants.

Contents Over the last 40 years, researchers have explored methods to non-surgically suppress fertility in animals. Immunocontraception has been used to control wildlife populations but does not confer long-term immunity. The gonadotropin-releasing hormone (GnRH) agonist deslorelin, formulated as an implant to provide 6-month to 1-year suppression of fertility in male dogs, is available commercially in some countries. Neither of these approaches provide permanent sterility. A single-dose, permanent treatment would be a valuable tool in dog and cat population control. The Michelson Prize and Grants (MPG) programme was initiated “to eliminate shelter euthanasia of healthy, adoptable companion animals and reduce populations of feral and free-roaming cats and dogs” offering a $25 million US prize for a non-surgical sterilant that is effective as a single treatment in both male and female dogs and cats. Michelson Prize and Grants programme has offered US $50 million in grant money for research and has attracted scientists worldwide. Approaches under study include gene therapy, small interfering RNA to inhibit reproductive targets and delivery of cytotoxins to pituitary gonadotrophs or GnRH producing neurons in the hypothalamus. Research in implant technology that could deliver compounds over an animal's lifetime is also underway. Details of funded grants and results to date can be found at: http://www.michelsonprizeandgrants.org/michelson-grants/research-findings. The next steps are translating the most promising research into products. The Alliance for Contraception of Cats and Dogs (ACC&D) is helping to research practical methods of marking sterilized animals to avoid costly retreatment and population modelling that will help guide field workers in use of resources for sterilization programmes.

Immunocastration (vaccination against boar taint) is an alternative method to prevent boar taint without the need for surgical castration. This study investigates the evolution of boar taint compounds in serum and fat, serum steroid compounds as well as behavior in immunocastrated pigs from 3 sire lines: 15 stress positive Belgian Piétrain (BP), 20 stress negative French Piétrain (FP), and 20 stress negative Canadian Duroc (CD). Hormone and boar taint compounds in serum were determined at 4 time points; boar taint compounds in fat were determined at 3 time points. Behavior, skin lesions, animal and pen fouling were also recorded before the first vaccination (V2). Aggressiveness, eating and drinking and general activity behavior declined from V2 for all sire lines. Pigs from BP were cleaner than FP and CD pigs. Even though immunocastration was effective in general (reduced testosterone, estradiol as well as androstenone in serum) for all sire lines, some individual pigs showed either androstenone or skatole levels in fat above cutoff values. While the immunocastration mechanism works as intended for androstenone, and also for skatole for the three sire lines, the risk of carcasses with boar taint compounds above cutoff levels (respectively 1.9 and 3.7%) still remains to some extent. ispartof: RESEARCH IN VETERINARY SCIENCE vol:124 pages:293-302 ispartof: location:England status: published

Immunocontraception has been suggested as an optimal alternative to surgical contraception in animal species. Many immunocontraceptive vaccines have been designed to artificially produce antibodies against gonadotropin-releasing hormone-I (GnRH-I) which remove GnRH-I from the vaccinated animals. A deficiency of GnRH-I thereafter leads to a lack of gonadotropins, resulting in immunocontraception. In this study, we initially developed three immunocontraceptive vaccines composed of GnRH-I, GnRH-II, and a GnRH-I and -II (GnRHI+ II) complex, conjugated to the external domain of Salmonella Typhimurium flagellin. As the GnRH-I+II vaccine induced significantly (p < 0.01) higher levels of anti-GnRH-I antibodies than the other two vaccines, we further evaluated its immunocontraceptive effects in male rats. Mean testis weight in rats (n = 6) inoculated twice with the GnRH-I+II vaccine at 2-week intervals was significantly (p < 0.01) lower than in negative control rats at 10 weeks of age. Among the six vaccinated rats, two were non-responders whose testes were not significantly reduced when compared to those of negative control rats. Significantly smaller testis weight (p < 0.001), higher anti-GnRH-I antibody levels (p < 0.001), and lower testosterone levels (p < 0.001) were seen in the remaining four responders compared to the negative control rats at the end of the experiments. Furthermore, seminiferous tubule atrophy and spermatogenesis arrest were found in the testis tissues of responders. Therefore, the newly developed GnRH-I+II vaccine efficiently induced immunocontraception in male rats. This vaccine can potentially also be applied for birth control in other animal species.

The feral pig populations of many countries continue to increase. Scientific studies on population size are scarce, while the numbers of reported observations on presence of and damage caused by feral pigs are increasing. Feral pigs can carry and spread several diseases (including zoonotic), but African Swine Fever (ASF) is of most concern. It is a highly transmissible viral disease associated with an extremely high mortality rate. Since 2009 ASF has appeared in several European countries, with cases being identified first among local feral pigs and consequently in domestic pig production units, indicating a clear linkage with the movement of the feral pig population and the spread of the disease across national boundaries. Control of feral pig populations is currently under discussion. Because massive culling raises questions of animal welfare and ethics, fertility control could represent an important and effective means to control feral pig populations. Contraceptive vaccines have been used with some degree of success in many wild species because they are able to provide a long-term effect without any consequent health problems. However, extensive and efficacious use of vaccines to control feral pig populations is not simple. The aim of this article was to review the progress in immunocontraception use in feral pigs, providing an account of the current status and future perspectives.

INTRODUCTION: Brazilian spotted fever (BSF), a lethal tick-borne Rickettsioses (2000 - 2018 >600 human deaths) involving synanthropic capybara as host. METHODS: We introduced an alternative to mitigate human-capybara conflicts and epidemiologic concerns of BSF. Complex aspects like transmission dynamics, risk areas, host mobility, and birth rate control, were considered to develop a prevention strategy using an anti-GnRH vaccine. RESULTS: The propositioned immunocontraceptive potentially remove and prevent the spread of BSF from endemic areas. CONCLUSIONS: We propose the anti-GnRH vaccine as a BSF prevention strategy based on these favorable results.

An important determinant in the selection of any contraceptive agent is the impact on ovarian function, both in the short and longer term. In this study, ovarian activity was monitored in mares immunised with one of the following vaccine formulations; native porcine zona pellucida (pZP), recombinant zona pellucida proteins ZP3 and ZP4 (reZP), pZP and reZP combined or a commercially available anti-GnRH vaccine. The ZP antigens were prepared in an adjuvant formulation consisting of 6% polymeric adjuvant (Montanide™ PetGel A, Seppic, France) and 500 μg polyinosinic-polycytidylic acid - TLR3-agonist (Poly(I:C) HMW VacciGrade™, Invivogen, USA). A vehicle-only control group was administered the adjuvant formulation without antigen. Ovarian activity was monitored using clinical observations (transrectal palpation and ultrasonography of the reproductive tract) in addition to blood sampling for serum progesterone and anti-Müllerian hormone (AMH) concentrations while employing a low sampling frequency. Treatments and measurements were initiated in December (southern hemisphere summer) and subsequent data collection was performed in January, February, March and May. Both reZP and anti-GnRH vaccination were associated with clinically evident ovarian suppression in the short term. Ovarian activity in mares administered a reZP or anti-GnRH vaccine was significantly different to adjuvant control and pZP treated mares. Serum AMH concentrations were different between pZP and anti-GnRH treated mares 3.5 months after the final vaccination. Serum AMH concentrations were significantly correlated with mare age, serum progesterone and ovarian volume.

The functional competence of leukemia inhibitory factor (LIF), as immunocontraceptive vaccine in mice, was investigated. Balb/c mice were divided into two groups of vaccinated and controls. The recombinant human LIF (rhLIF) protein and phosphate buffer saline was emulsified with Freund's adjuvant and injected into vaccinated and control groups, respectively. Theinhibition of implantation was evaluated in mice uterine. The concentration of secreted interferon-γ (IFN-γ) and interleukin (IL)-4 were measured in cultured splenocyte of mice stimulated by rhLIF. The expressions of immune responsive gene 1 (IRG-1), cochlin (COCH), amphiregulin(Ar), and heparin-binding EGF-like growth factor (HB-EGF) genes were determined. Mice were assessed for inhibition of fertility after delivery, reversibility of immune response against rhLIF, and survival rate. Active immunization of mice with rhLIF resulted in reduction of the implantation and fertility rate up to 80.49% and 75%, respectively. All mice produced a high titer of anti-rhLIF antibodies in serums and vaginal fluids washes after 16 weeks; however, these antibodies were cleared from vaginal fluid washes after six months. A significant down-regulation in mRNA levels of IRG-1, Ar and HB-EGF was observed in vaccinated group compared to controls; however, no significant change in the expression profile of cochlin gene was detected. The results showed that rhLIF prevented pregnancy in a high percentage of female mice. Although the immunization of female Balb/c mice with rhLIF inhibited fertility and expression of genes associated with this molecule, further studies are needed to support this protein as a suitable candidate for contraceptive vaccine in mammals.

Boar stations raise only entire male pigs for selection as reproductive boars, but the majority of them will fail the selection process, ending at slaughter with a high risk of boar tainted meat. The aim of this study was to investigate whether a single dose of Improvac given to 16-week old boars had a negative effect on their subsequent sperm numbers and motility in 16 artificial insemination boars. We also aimed to generate more knowledge on incidence of boar taint at slaughter among Finnish pigs, compare production performances as average daily gain, feed conversion ratio, and carcass and meat quality (lean meat percentage, back fat, pH, color, androstenone, and skatole) of immunocastrated boars (n = 248) with those of entire boars (n = 268). Moreover, we aimed also to explore whether a fat biopsy taken at 16 weeks of age could already reveal the presence of boar taint compounds and be predictive of boar taint development at slaughter age. We found that 32% of entire boars (Figen Landrace, Figen Large White, and their crossbreed) slaughtered at an age of 25 weeks presented levels of androstenone and/or skatole above the threshold for boar taint in their meat. These boars (control) had higher androstenone and skatole levels in the back fat samples at slaughter (0.77 ± 0.55 and 0.09 ± 0.06 μg/g, respectively, mean ± standard deviation) than those in the immuno group (0.20 ± 0.25 and 0.06 ± 0.03 μg/g, respectively, P < 0.001). A single dose of anti-GnRH vaccine, given at 16 weeks of age, did not affect future sperm numbers and motility of boars selected for artificial insemination. We found no difference in the levels of testosterone, anti-GnRH antibodies titers, testicle morphology, and sperm numbers and motility between the boars vaccinated once, at 16 weeks of age, with anti-GnRH vaccine and the control boars (no vaccination). There were no differences in average daily gain, feed conversion ratio, lean meat percentage, and back fat between the immunocastrated boars and entire boars. Meat from immunocastrated boars had a higher pH and better color than meat from entire boars (P < 0.001), suggesting slightly improved meat quality.

Effects of sex class (physically castrated, PC or immunologically castrated, IC) and diet (0 or 5mg/kg ractopamine hydrochloride, RAC) on characteristics of ham and bellies were determined from pigs slaughtered in three groups with similar ending live weights. One carcass per pen per marketing group (n=8) was selected to evaluate further processing characteristics. Data were analyzed as a 2×2 factorial design with a split plot in time and fixed effects of sex, diet, marketing group, and their interactions. IC fresh bellies were thinner (P0.01) and softer (P0.01) than PC bellies. IC hams and bellies were leaner (P0.05) than those from PC pigs. RAC feeding did not affect (P0.05) fresh ham or belly characteristics but decreased (P0.01) fat in cured PC bellies. Marketing group affected (P0.05) fresh quality, processing characteristics, and composition of hams and bellies. Immunological castration and RAC produced leaner finished products but did not alter processing yield of hams or bacon.

Problem The development of a new and suitable contraceptive methods, as well as in-depth and systematic research into underlying contraceptive mechanisms, is crucial. IZUMO1 plays an important role in the fusion of the sperm and ovum during fertilization. Izumo−/− mice are infertile. Therefore, IZUMO1 may be a potential target for the development of a contraceptive vaccine. Method of study Linear B-cell epitopes (BCE) were identified in IZUMO using biosynthetic peptides and used to immunize female mice. Results Five IZUMO BCE were identified: DLVLDCL177-183, YSFYRV196-201 (named BCE-2), YLT217-219, SMVGPED221-227, and DAGNY228-232. Active immunization with the BCE-2 vaccine sharply decreased the fertility rate in female mice in a safe and reversible manner. In vitro fertilization showed that the BCE-2 vaccine interferes with and blocks the fusion of the sperm and the ovum. Conclusions B-cell epitopes-2 may be a new candidate for the development of contraceptive vaccine due to its effectiveness, safety, and reversibility.

International audience; Due to the initiative to stop piglet castration, meat from entire male pigs is expected to take important share on the European market which can affect dry-cured ham industry. In the present study, hams of entire males (EM) and immunocastrates (IC) were submitted to dry-curing process. Sex category and salting regime were evaluated using standard (18days; HS) and shortened salting (6days; LS). At the end of processing, compared to HS, LS hams had lower (40%) salt content, were more proteolysed, were less salty, and had softer texture and different volatile profile. Sex effect was less evident; still, hams from EM exhibited higher processing losses and salt intake, and were drier, less marbled, harder, and more intensively coloured than IC hams. The panellists perceived higher off-flavours in hams with high boar taint compounds (correlation 0.67 and 0.53 for skatole and androstenone, respectively). The effect of sex category on volatile profile was negligible.

The objective of this study was to compare pork quality and sensory characteristics of pork from gilts, physical castrates, entire males, and immunological castrates. Loins (Longissimus thoracis et lumborum) were collected at harvest, aged for 10 days, and subsequently cut into chops and roasts. Two chops and one roast were frozen for a minimum of 14 days to a maximum of 30 days and chops and roasts from the same loin were evaluated in fresh form. A trained sensory panel evaluated the samples and results showed that gilt pork, physical castrate pork, and immunological castrate pork were similar in terms of boar odor and pork flavor. The evaluated pork quality characteristics showed no differences among sexes except for marbling in the frozen samples (P0.05). Results suggest that pork from immunologically castrated males is similar to pork from physical castrates in terms of sensory and pork quality characteristics and between fresh and frozen products.

The objective was to determine the effects of time after a second dose of anti-GnRF immunization on fresh belly characteristics and slicing yields of immunologically castrated (IC) barrows, physically castrated (PC) barrows and gilts slaughtered at 24 weeks of age. The second dose was staggered so that IC barrows were slaughtered at 4, 6, 8, or 10 weeks after the second dose. Fresh belly characteristics (N=141) were collected at slaughter and bacon was manufactured commercially. The main effects in the model were treatment and the random effects of block and block within replication. Thickness, flop distance, and lipid content increased (L; P

Background Stray dogs are the reservoirs and carriers of rabies and are definitive hosts of echinococcosis. To control the overpopulation of stray dogs, zona pellucida 3 (ZP3), a primary receptor for sperm, is a potential antigen for developing contraceptive vaccines. To enhance the immune responses and contraceptive effects of canine ZP3 (cZP3), dog gonadotropin-releasing hormone (GnRH) and a T cell epitope of chicken ovalbumin (OVA) were selected to construct two fusion proteins with cZP3, ovalbumin-GnRH-ZP3 (OGZ) and ovalbumin-ZP3 (OZ), and their contraceptive effects were evaluated in mice. Methods The synthesized DNA sequences of OGZ and OZ were cloned into plasmid pET-28a respectively. The fusion proteins OGZ and OZ were identified by SDS-PAGE and Western blot. Mice were immunized with OGZ, OZ and cZP3, and the infertility rates were monitored. Mice immunized with mouse ZP3 (mZP3) or adjuvant alone were used as positive control and negative control, respectively. cZP3- and GnRH-specific antibodies (Abs) were detected by ELISA. The bindings of the Abs to oocytes were detected by indirect immunofluorescence assay. The paraffin sections of mice ovaries were observed under microscope for analyzing pathological characteristics. Results SDS-PAGE and Western blot analyses showed that the two fusion proteins OGZ and OZ were correctly expressed. ELISA results showed that OGZ vaccine induced both cZP3- and GnRH-specific Abs, and OZ vaccine induced cZP3-specific Ab, which lasted for up to 168 days. The levels of follicle stimulating hormone (FSH) and estradiol (E2) in sera were significantly decreased in OGZ immunized mice. Indirect immunofluorescence results showed that Abs induced by cZP3 and mZP3 could bind to the mouse ZP and dog ZP each other. Compared with the adjuvant group, all vaccine immunized groups significantly decreased the fertility rate and mean litter size. Interestingly, the fertility rate in OGZ-immunized group is the lowest, and only 1 mouse out of 10 mice is fertile. Histological analysis of murine ovarian sections indicated that most of the infertile mice in the immunized groups lacked mature follicles as well as accompanied by inflammatory infiltration. Meanwhile, immunization with OGZ decreased the number of corpora lutea in the infertile mice. Conclusions The fusion protein OGZ resulted in the lowest fertility rate and the least mean litter size in the immunized mice. OGZ might be a promising antigen for developing a new contraceptive vaccine for stray dog controlling.

Wildlife and humans are increasingly competing for resources worldwide, and a diverse, innovative, and effective set of management tools is needed. Controlling abundance of wildlife species that are simultaneously protected, abundant, competitive for resources, and in conflict with some stakeholders but beloved by others, is a daunting challenge. Free-ranging horses (Equus caballus) present such a conundrum and managers struggle for effective tools for regulating their abundance. Controlling reproduction of female horses presents a potential alternative. During 2009-2017, we determined the long-term effectiveness of GnRH vaccine (GonaCon-Equine) both as a single immunization and subsequent reimmunization on reproduction and side effects in free-ranging horses. At a scheduled management roundup in 2009, we randomly assigned 57 adult mares to either a GonaCon-Equine treatment group (n = 29) or a saline control group (n = 28). In a second roundup in 2013, we administered a booster vaccination to these same mares. We used annual ground observations to estimate foaling proportions, social behaviors, body condition, and injection site reactions. We found this vaccine to be safe for pregnant females and neonates, with no overt deleterious behavioral side effects during the breeding season. The proportion of treated mares that foaled following a single vaccination was lower than that for control mares for the second (P = 0.03) and third (P = 0.08) post-treatment foaling seasons but was similar (P = 0.67) to untreated mares for the fourth season, demonstrating reversibility of the primary vaccine treatment. After two vaccinations, however, the proportion of females giving birth was lower (P

Silica nanoparticles (SiNPs) have been shown to have significant potential for drug delivery and as adjuvants for vaccines. We have simulated the adsorption of GnRH-I (gonadotrophin releasing hormone I) and a cysteine-tagged modification (cys-GnRH-I) to model silica surfaces, as well as its conjugation to the widely-used carrier protein bovine serum albumin (BSA). Our subsequent immunological studies revealed no significant antibody production was caused by the peptide-SiNP systems, indicating that the treatment was not effective. However, the testosterone response with the native peptide-SiNPs indicated a drug effect not found with cys-GnRH-I-SiNPs; this behaviour is explained by the specific orientation of the peptides at the silica surface found in the simulations. With the BSA systems, we found significant testosterone reduction, particularly for the BSA-native conjugates, and an antibody response that was notably higher with the SiNPs acting as an adjuvant; this behaviour again correlates well with the epitope presentation predicted by the simulations. The range of immunological and hormone response can therefore be interpreted and understood by the simulation results and the presentation of the peptides to solution, paving the way for the future rational design of drug delivery and vaccine systems guided by biomolecular simulation.

Objectives Non-surgical contraceptive management of free-roaming cat populations is a global goal for public health and humane reasons. The objectives of this study were to measure the duration of contraception following a single intramuscular injection of a gonadotropin-releasing hormone-based vaccine (GonaCon) and to confirm its safe use in female cats living in colony conditions. Methods GonaCon (0.5 ml/cat) was administered intramuscularly to 20 intact female cats (queens), and saline was administered to 10 queens serving as sham-treated controls. Beginning in late February, 4 months after injection, all cats were housed with fertile male cats in a simulated colony environment. Time to pregnancy, fetal counts and vaccine-elicited injection-site reactions were evaluated. Results All control cats (n = 10/10) and 60% (n = 12/20) of vaccinated cats became pregnant within 4 months of the introduction of males. Two additional vaccinates became pregnant (70%; n = 14/20) within 1 year of treatment. Average fetal counts were significantly lower in vaccinated cats than in control cats. Vaccinates had a significantly longer ( P = 0.0120) median time to conception (212 days) compared with controls (127.5 days). Injection-site reactions ranging from swelling to transient granulomatous masses were observed in 45% (n = 9/20) of vaccinated cats. Conclusions and relevance A single dose of GonaCon provided contraception lasting for a minimum of 1 year in 30% (n = 6/20) of treated cats. The level of contraception induced by this GonaCon dose and vaccine lot was not sufficiently effective to be recommended for use in free-roaming cats.

An alternative to surgical sterilization for fertility control of animals (wild, zoo, farm, and domestic) is needed to prevent problems related to overpopulation, including culling and relocation. A PubMed and Google Scholar database search was conducted using the keywords 'contraceptive vaccine animals,' 'immunocontraception animals,' 'non-surgical sterilization animals,' 'PZP vaccine,' and 'GnRH vaccine.' The searches from 1972 to 2015 yielded over 1500 publications. These articles were read, and 375 were selected for detailed analysis. Articles referenced in these publications were also thoroughly examined. PZP and GnRH contraceptive vaccines (CVs) have been extensively investigated for fertility control of wild, zoo, farm, and domestic animal populations. Both vaccines have shown tremendous success with PZP vaccines taking the lead. Novel technologies and targets are being developed to improve existing vaccines and generate second-generation CVs. Single-shot vaccines, which can be delivered remotely, will greatly advance the field of immunocontraception for animal use with potential human application.

Problem Necessity to elicit antibody response above the protective threshold titres by sexually active women immunized to prevent pregnancy. Method of study Recombinant hCGβ-LTB vaccine expressed as both DNA and protein. Balb C mice employed for testing immunogenicity. Results Necessity to give three primary injections of the vaccine to elicit proper antibody response. Immunization twice with DNA form of the vaccine at fortnightly interval followed by the protein elicits a distinctly higher antibody response than proteinic vaccine alone. Antibodies generated are bio-effective against hCG. Conclusion Immunization with the DNA form of the recombinant hCGβ-LTB vaccine twice at fortnightly interval followed by the proteinic form of the vaccine induces distinctly higher antibody response.

Problem In our previous study on adult male mice, we had identified one immunodominant epitope in hEppin and three epitopes in hFSHR that caused fertility inhibition. But it only demonstrated a moderate inhibitory effect on fertility, and the antifertility effect was unsatisfactory. Method of study Based on the protein prime–peptide boost inoculation modalities, we further investigated whether the antifertility capacity could be enhanced by a combined immunization with the two antigens. Results The results displayed a enhanced suppressed fertility (F2EP2C 6.67%) in male mice similar to that seen after four separate administrations of the two proteins (F12E-4 5%). The most likely mechanism by which this antifertility efficacy was achieved was probably through the production of antibodies that led not only to impairment of spermatogenesis but also to inhibition of sperm motility. Moreover, this treatment also induced high concentrations of neutralizing antibodies which were secreted into the lumen of the epididymis. Conclusion Thus, a combination immunization with hFSHR and hEppin enhanced the contraceptive effects and may provide a better means of immunocontraception.

Urokinase-type plasminogen activator (uPA) is closely related to male reproduction. With the aim of investigating the possibility for uPA as a potential contraceptive target, in the present work, Kunming male mice were immunized by human uPA subcutaneous injection at three separate doses for 3 times. Then the potency of the anti-human uPA antibody in serum was analyzed, and mouse fertility was evaluated. Serum antibody titers for human uPA in immunized groups all reached 1:10,240 or higher levels by enzyme linked immunosorbent assay, and mating experiments revealed that pregnancy rates and the mean number of embryos implanted after mating declined obviously (P < 0.05) when compared with control groups. However, the mating capacity and reproductive organ weights had no obvious change, and histological analysis of the testes and epididymides also showed normal morphology for immunized male mice. Sperm function tests suggested that the sperm concentration, sperm viability, sperm motility, and in vitro fertilization rate for the cauda epididymis sperm in uPA-immunized groups were lower than those in the controls (P < 0.05). Together, these observations indicated that subcutaneous injection human uPA to the male mice could effectively reduce their fertility, and uPA could become a new target for immunocontraception in male contraceptive development.

Single and combined effects of ractopamine supplementation (RAC, 7.5 vs. 0 ppm), castration method (surgical castration: SC vs. immuno-castration: IM) and genotype (genotype A: GA vs. GB containing 25% or 50% Pietrain) were determined on longissimus muscle (LM) fiber traits and quality of pork (n=512). RAC increased fiber IIX cross-sectional area (P=0.009) and decreased glycolytic potential (P=0.02) and pork tenderness (P

This study validated the effect of gender (female, immunocastrated male; n = 50), electrical stimulation (none or 150 mA constant current for 30 s at 2 min post-slaughter) and ageing period (2 or 14 d) on the eating quality of pork roast and stir fry sourced from the loin (M. longissimus thoracis et lumborum) and silverside (M. biceps femoris) and steak from the loin only. Moisture infusion was applied to 2 d aged, non-stimulated primals as a positive control treatment. Neither gender nor ageing period influenced (P > 0.05) eating quality. Electrical stimulation and moisture infusion were each effective interventions in improving pork eating quality, but their effects were inconsistent between the five cuts evaluated. No interventions achieved the fail rate target of

Background: Population control of domestic, wild, invasive, and captive animal species is a global issue of importance to public health, animal welfare and the economy. There is pressing need for effective, safe, and inexpensive contraceptive technologies to ad-dress this problem. Contraceptive vaccines, designed to stimulate the immune system in order to block critical reproductive events and suppress fertility, may provide a solution. Fil-amentous bacteriophages can be used as platforms for development of such vaccines. Objective: In this review authors highlight structural and immunogenic properties of fila-mentous phages, and discuss applications of phage-peptide vaccines for advancement of immunocontraception technology in animals. Results: Phages can be engineered to display fusion (non-phage) peptides as coat proteins. Such modifications can be accomplished via genetic manipulation of phage DNA, or by chemical conjugation of synthetic peptides to phage surface proteins. Phage fusions with antigenic determinants induce humoral as well as cell-mediated immune responses in ani-mals, making them attractive as vaccines. Additional advantages of the phage platform include environmental stability, low cost, and safety for immunized animals and those ad-ministering the vaccines. Conclusion: Filamentous phages are viable platforms for vaccine development that can be engineered with molecular and organismal specificity. Phage-based vaccines can be pro-duced in abundance at low cost, are environmentally stable, and are immunogenic when administered via multiple routes. These features are essential for a contraceptive vaccine to be operationally practical in animal applications. Adaptability of the phage platform also makes it attractive for design of human immunocontraceptive agents.

Vaccines based on gamete specific proteins have been proposed for fertility inhibition. In the present study, immunogenicity and contraceptive potential of E. coli-expressed recombinant fusion protein TT-KK-ZP3-GGG-Iz, comprising promiscuous T cell epitope of tetanus toxoid (TT) followed by dilysin linker (KK), a fragment of dog zona pellucida glycoprotein-3 (ZP3), triglycine spacer (GGG) and a fragment of dog Izumo (Iz) without any affinity tag has been evaluated in female FvB/J mice. In addition, recombinant TT-KK-ZP3 and Izumo linked to the promiscuous T cell epitope of bovine RNase (bRNase-KK-Iz) and their physical mixture were also used. SDS-PAGE and immunoblot studies revealed ∼32kDa band corresponding to TT-KK-ZP3-GGG-Iz, ∼22kDa band of TT-KK-ZP3 and ∼11kDa band of bRNase-KK-Iz. Groups of mice immunized with the above recombinant proteins led to the generation of high antibody titres against the respective proteins. Immunization with recombinant TT-KK-ZP3-GGG-Iz generated higher antibody titre as compared to mice immunized with physical mixture of TT-KK-ZP3 and bRNase-KK-Iz. Antibodies against TT-KK-ZP3-GGG-Iz and TT-KK-ZP3 recognized mouse and dog ZP and those against TT-KK-ZP3-GGG-Iz and bRNase-KK-Iz recognized mouse and dog acrosome-reacted sperm in an indirect immunofluorescence assay. Immune sera from groups of mice immunized with the above recombinant proteins led to a significant reduction in mouse in vitro fertilization. Mating studies revealed significant reduction in fertility as compared to adjuvant control group. Highest infertility was observed in group of mice immunized with TT-KK-ZP3 followed by TT-KK-ZP3-GGG-Iz. Infertility was associated with the antibody titres against ZP3, whereas no association in the inhibition of fertility and antibody titres against Izumo was observed. In conclusion, these studies revealed the contraceptive potential of ZP3, which could not be further enhanced by the inclusion of Izumo.

Measurement of circulating luteinizing hormone (LH) concentrations in cats and temporal changes following ovariohysterectomy (OHE) or possibly GnRH vaccination may be informative for assessing their fertility, contraception or sterilization status. In this study, serum LH concentrations were measured in domestic cats (n = 6) immediately prior to and up to 120 days post-OHE. Basal LH concentrations of females previously subjected to OHE (n = 4; ~1.5 years post-OHE) were compared pre- and post-vaccination with a GnRH immunocontraceptive, and to LH concentrations in intact females. Basal serum LH concentrations (2.67 ± 0.43 ng/ml; mean ± SEM) in intact females increased (p

Contents Sterilization is a key strategy to reduce the number of domestic cats entering and killed in shelters each year. However, surgical sterilization is expensive and labour-intensive and cannot fully address the 70 million free-roaming cats estimated to exist in the United States. GonaCon™ is a gonadotropin-releasing hormone vaccine originally developed for use as a wildlife immunocontraceptive. An earlier formulation was tested in domestic cats and found to be safe and effective for long-term contraception. However, the current Environmental Protection Agency (EPA)-registered formulation consists of a different antigen-carrier protein and increased antigen concentration and has never been tested in cats. A pilot study was undertaken to evaluate the short-term safety of a single GonaCon immunization, assess the consequences of vaccinated cats receiving an accidental second GonaCon injection and determine the humoral immune response to immunization. During Phase 1, cats in Group A (n = 3) received a single intramuscular injection of GonaCon and Group B (n = 3) received a single intramuscular injection of saline. During Phase 2, Group A received a second GonaCon injection and Group B received their initial GonaCon injection. All cats developed GnRH antibodies within 30 days of vaccine administration. The endpoint titre (1:1,024,000) was similar among all cats, and levels remained high throughout the duration of the study. Four cats developed a sterile, painless, self-limiting mass at the site of injection. The mean number of days to mass development was 110.3 (range, 18–249 days). In conclusion, this preliminary study suggests that the EPA-registered GonaCon formulation is safe for continued testing in domestic cats, an accidental revaccination should not increase the risk of a vaccine reaction and the EPA-registered formulation effectively elicits a strong humoral immune response.

Leukocytospermia is a physiologic condition defined as human semen with a leukocyte count of >1 x 106 cells/ml that is often correlated with male infertility. Moreover, bacteriospermia has been associated with leukocytospermia ultimately leading to male infertility. We have found that semen samples with >1 x 106/ml leukocytes and/or bacteriospermia have oxidative predominance as evidenced by augmented protein carbonyl and lipid peroxidation status of the semen which is implicated in sperm dysfunction. It has been reported that Streptococcus agalactiae is present in bacteriospermic samples. Previous research has shown that human leukocyte antigen beta chain paralog (HLA-DRB) alleles interact best with the infected sperm cells rather than the non-infected cells. Little is known about the interaction of major histocompatibility complex (MHC) present on leukocytes with the sperm upon bacterial infection and how it induces an immunological response which we have addressed by epitope mapping. Therefore,...

The common physical and chemical methods for controlling rat pest are less than satisfactory and inhumane. Immunocontraception approach has been considered more humane and it can be accomplished by inducing the relevant host immune response that block further development of reproductive gametes. ZP3 proteins are known to play very important role during sperm-ovum fertilization. It is a self-antigen and only localized in female ovaries. Therefore, an immunization with ZP3 protein elsewhere will induce a generalize host immune response against ZP3 protein. This study employed rat ZP3 (rZP3) gene prepared from its cDNA of Rattus rattus diardii. It was delivered and expressed in vivo by naked plamid DNA (DrZP3) or recombinant ZP3-Adenovirus (Ad-rZP3). Expression studies in vitro with DrZP3 or Ad-ZP3 showed rZP3 proteins were successfully expressed in Vero cells. Hyperimmune serum against rZP3 that were prepared by immunizing several rats with purified rZP3-pichia yeast fusion protein showed it blocked sperms from binding DrZP3-transfected Vero cells. Female Sprague Dawley rats immunized with DrZP3 demonstrated a long-term effect for significant reduction of fertility up to 92.6%. Ovaries from rats immunized with DrZP3 were severely atrophied with disappearance of primordial follicles from ovarian cortex with an increased in the amount of oocyte-free cell clusters. Female rats immunized with Ad-rZP3 demonstrated 27% reduction of fertility. The infertility induced by Ad-rZP3 is comparatively low and ineffective. This could be due to a strong host immune response that suppresses the recombinant virus itself resulted in minimum rZP3 protein presentation to the host immune system. As a result, low antibody titers produced against rZP3 is insufficient to block oocytes from maturity and fertilization. Therefore, immunization with DrZP3 for immunocontraception is more effective than Ad-rZP3 recombinant adenovirus. It is proposed to explore further on the use of adenovirus or other alternative viruses to deliver ZP3 protein and for the development of enhanced expression of rZP3 in target host.