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Fertility control of feral equids is difficult. A 4-month pilot study was conducted with a hormone-free intrauterine device (iUPOD). There was evaluation of i) device retention; ii) contraceptive efficacy; iii) fertility following device removal; iv) effects of device on estrous cycle periodicity and; v) abundance of biofilm on devices after removal from the uterus. The iUPODs were inserted trans-cervically in eight mares at random stages of the estrous cycle. Mares were confined in a paddock with a stallion the following day and remained with the stallion for 120 days. Transabdominal detection of the iUPOD, using a non-invasive handheld magnetic detector wand, was performed weekly. Mares were examined using transrectal ultrasonography on days 0 (Time at insertion = day 0), 14, and 30, and subsequently every third week to assess number and size of follicles, corpora lutea, and whether there was intrauterine fluid (IUF) present. The mares and stallion were observed daily for mating behavior. Weekly samples were assayed for progesterone (P 4 ) at day 0 and until 3 weeks subsequent to stallion removal. None of the mares became pregnant while fitted with the iUPOD. Two of four mares conceived within 30 days subsequent to iUPOD removal. Three of eight mares fitted with the device had periods greater than 14 days with P 4 concentrations <1 ng/mL, and seven of eight mares had periods greater than 14 days with P 4 concentrations>1 ng/mL. There was a marked abundance of biofilm on devices of two mares at the time of device removal., (Copyright © 2021 The Authors. Published by Elsevier B.V. All rights reserved.)

Wild boar and feral swine number and range are increasing worldwide in parallel with their impact on biodiversity and human activities. The ecological and economic impact of this species include spread of diseases, vehicle collisions, damage to crops, amenities and infrastructures and reduction in plant and animal abundance and richness. As traditional methods such as culling have not contained the growth and spread of wild boar and feral pigs, alternative methods such as fertility control are now advocated. We used empirical data on two isolated wild boar populations to model and compare the effects of different regimes of culling and fertility control on population trends. We built a Bayesian population model and applied it to explore the implications for population control of various management options combining culling and/or contraception. The results showed that, whilst fertility control on its own was not sufficient to achieve the target reduction in wild boar number, adding fertility control to culling was more effective than culling alone. In particular, using contraceptives on 40% of the population to complement the culling of 60% of the animals, halved the time to achieve our target reduction compared with culling only. We conclude that, assuming the effort of adding fertility control to culling was found to be cost-effective in terms of population reduction, these two methods should be used simultaneously if a rapid decrease in wild boar number is required for a closed population., Competing Interests: The authors have declared that no competing interests exist.

Overabundant populations of ungulates have caused environmental degradation and loss of biological diversity in ecosystems throughout the world. Culling or regulated harvest is often used to control overabundant species. These methods are difficult to implement in national parks, other types of conservation reserves, or in residential areas where public hunting may be forbidden by policy. As a result, fertility control has been recommended as a non-lethal alternative for regulating ungulate populations. We evaluate this alternative using white-tailed deer in national parks in the vicinity of Washington, D.C., USA as a model system. Managers seek to reduce densities of white-tailed deer from the current average (50 deer per km2) to decrease harm to native plant communities caused by deer. We present a Bayesian hierarchical model using 13 years of population estimates from 8 national parks in the National Capital Region Network. We offer a novel way to evaluate management actions relative to goals using short term forecasts. Our approach confirms past analyses that fertility control is incapable of rapidly reducing deer abundance. Fertility control can be combined with culling to maintain a population below carrying capacity with a high probability of success. This gives managers confronted with problematic overabundance a framework for implementing management actions with a realistic assessment of uncertainty.

Relevance: Non-surgical contraceptives or sterilants need regulatory approval to be sold for that use. This approval process gives veterinarians the information required to assess the benefits and risks of each product, and to provide comprehensive information on the required dose, method and duration of use, safety and effectiveness., Aim: This article reviews the information that must be developed and provided to regulatory agencies worldwide, with a focus on the European Union and the United States, in order to achieve regulatory approval., Processes: The main components of developing a drug include developing extensive information on the safety and effectiveness of the product, and also the safety to the environment and to humans handling and administering the drug. Most importantly, a robust method of manufacturing both the drug itself and the formulated drug product (pill, liquid implant or injection) must be developed to assure quality and consistency in each batch. This information is then compiled and submitted to regulatory agencies; in the United States, this includes the Food and Drug Administration, the United States Department of Agriculture and the Environmental Protection Agency, and, in Europe, the European Medicines Agency., Challenges: Because of the unique nature of non-surgical contraceptives for use in cats and dogs, particularly the desire to have these products last over multiple years, there are special challenges to their regulatory approval that are discussed in this review., (© The Author(s) 2015.)

Overview: Trap-neuter-return (TNR) for cat management is transitioning from an enterprise driven mainly by an urge to 'help' into an enterprise that draws useful guidance and precedent from the fields of population biology and wildlife management. This transition is in its infancy, however. At the present time many TNR programs do not produce substantial and persistent reductions in cat populations, and those that do often fail to effectively document this achievement or to publicize their success., Challenges: As a result, TNR has become increasingly controversial, with TNR advocates and wildlife conservationists often staking out fundamentally incompatible positions. This may ultimately prove to be an unproductive debate, since public opinion in developed countries is unlikely to support a total abandonment of TNR in favor of widespread cat management using lethal methods, and since wildlife advocates are unlikely to support TNR as it is typically practiced., Advancements: In contrast, improving the effectiveness of TNR as a population management tool can benefit both cats and wildlife, potentially on a broad scale. Making these advancements requires the diligent promotion, dissemination and adoption of tools like population modeling, population monitoring and adaptive management. By virtue of their training and exposure to the scientific method, veterinarians are uniquely well positioned to translate the more technical aspects of these approaches to TNR practitioners, and to facilitate their wider use., Aim: The purpose of this review is to describe for a veterinary audience how to facilitate more effective sterilization-based management of outdoor cats, using a combination of theoretical knowledge derived from population modeling and empirical knowledge derived from population monitoring. Using both of these information sources synergistically can offer a viable pathway to better management outcomes., (© The Author(s) 2015.)

Several fertility control agents have recently been registered with the U.S. Environmental Protection Agency for management of wildlife or other free-ranging animals. The registration of GonaCon Immunocontraceptive Vaccine for use in white-tailed deer (Odocoileus virginianus) and OvoControl for use in Canada geese (Branta canadensis) and pigeons (Columba livia) has caused state wildlife and land management agencies to review their regulatory authority over the use of contraceptives in wildlife. As a result, many states are taking steps to ensure legislation or policies are current with emerging technologies. This article examines the various approaches states are taking to regulate the use of contraceptives. Regardless of the final regulatory approach, biological, social, economic, and political implications must all be discussed as this new tool is introduced into the field of ona wildlife management. Thoughtful consideration of all aspects of wildlife contraceptive use will lead to the development of sound, best management practices for current and future products.

There are only two nonlethal approaches with which to manage wildlife populations: remove excess individuals or decrease reproductive rates. In the case of wild horse management, the latter has already been shown to be a more humane and less costly approach. Contraception has been known for many years to be effective in wild horses with regard to both fertility and population alteration. Field testing under real-world management situations is a critical aspect of wildlife contraception assessment. Field testing also requires documentation to justify eventual large-scale use of fertility control in population management. Furthermore, it is likely that full support by the managing agencies and acceptance of fertility control by the public will not occur until success has been demonstrated at the population level in the field. Because the transition from laboratory and captive animal trials to the real world of field research and testing of management potential in free-ranging wildlife is both essential and difficult, we identify considerations for optimizing success in the field, especially for controlling wild horse and white-tailed deer populations. This study identified the following categories for assessment: 1) field-specific logistics and tactics (including access to and identification of horses, censuses, pregnancy testing, and behavior monitoring), 2) training of field personnel and managers (including vaccine biology, preparation and delivery, and basic field methodology), 3) essential field considerations for enabling management (including population variables, environmental variables, and modeling), and 4) pitfalls of field contraception. In this assessment, we will highlight the capability for coincident pursuit of research and management and will explore field considerations applicable to many species where fertility control has potential as a management tool.

Contraception offers potential as a tool for managing certain diseases in wildlife, most notably venereally transmitted diseases or diseases transmitted at parturition. Brucellosis is an excellent example of an infectious disease present in wild populations that could potentially be managed through immunocontraception. Previous studies in bison (Bison bison) suggest that a single injection of GonaCon (National Wildlife Research Center, U.S. Department of Agriculture/Animal and Plant Health Inspection Service/Wildlife Services, Fort Collins, Colorado 80521, USA) results in 3 or more yr of infertility. Ongoing studies will determine if the use of GonaCon in bison decreases shedding of Brucella abortus from infected animals and will better define the duration of infertility following a single injection

Unlabelled: GUIDELINES RATIONALE: Cats are among the most commonly kept domestic pets, and coexist with humans in a variety of different circumstances. Cats are sentient beings and, as such, humans have a responsibility for cat welfare where humans and cats coexist. Because cats reproduce efficiently, measures to control populations are frequently needed, but these should be based on ethical and humane approaches., Framework: These consensus guidelines from the International Society of Feline Medicine's Welfare Advisory Panel provide a framework for the approach to welfare and population control measures, primarily among unowned cats and those going through a homing programme.

Zimbabwe does not feature much on the current debate of fertility transition in sub-Saharan Africa. This article is trying to fill this gap by analysing the ZDHS data. The total fertility rate of Zimbabwe was close to 7 births during independence in 1980. However, it has declined to 3.8 in 2006. This does not only show that fertility in Zimbabwe has been declining over the years, but it is one of the lowest in the region. The fertility trend observed is mainly explained by use of contraception. The contraceptive prevalence rate was 60 percent in 2006. It is noted that the contraceptive uptake has continued to increase even during the years when Zimbabwe was going through serious political, economic, social and health challenges. This is because the groundwork done on the family planning programme soon after independence put a solid foundation in motivating women to use contraception.

The study was to assess the types and trend of female sterilization between January 1985 and December 2009 (25 years) in Jos, Central Nigeria. There were 25,313 new acceptors of modern contraceptive methods out of which 4,951 (19.6%) were female sterilizations. Minilaparotomy was the commonest method of female sterilization. Local anaesthesia was the commonest anaesthetic utilized. The women were mostly women of relatively older age, grandmultiparous and with large family size. The women were of mean of 38.4 years, and 60% had more than 5 children at the time of sterilization. Interval sterilization constituted 78.5% of the female sterilizations. The acceptance of female sterilization, however, has declined over the years, as acceptance of the long acting contraceptive implants increases. Female sterilization by minilaparotomy under local anaesthesia was found to be feasible, cost effective and acceptable by majority of clients, and recommended for integration into minor gynaecological procedures in our institutions.

The objectives of this survey were to identify women's level of KAP toward FP; identify possible barriers to using FP; determine pregnancy spacing pattern; and ascertain the level of FP promotion by health workers. This was a 2-weeks cross-sectional survey at all maternity units in Butembo of post-partum women. 572 women were interviewed. FP knowledge was high (76%), perception good (80%). Majority used traditional methods (65%), mostly Calendar method (72%). Barriers to using modern FP included lack of knowledge, fear of side effects, religious considerations and husband opposition. Unmet need for spacing and limiting was high (21 & 31%). For majority (56%), pregnancy spacing met WHO's Healthy Timing and Spacing of Pregnancy recommendations. Promotion of FP was poor (42%). Training of health workers, advocating modern contraception, improving FP services in all public health facilities and promoting FP on each contact of women is highly recommended in this city.

This study constructed matrix population models to explore feral cat population growth for a hypothetical population (a) in the absence of intervention; (b) with a traditional surgical sterilization-based trap, neuter, and return program; and (c) with a single treatment 3-year nonsurgical contraception program. Model outcomes indicated that cessation of population growth would require surgical sterilization for greater than 51% of adult and 51% of juvenile (<1 year) intact female cats annually, assuming an approximate 3-year mean life span. After the population stabilizes, this would equate to sterilizing approximately 14% of the total female population per year or having approximately 71% of the total female and 81% of the adult female population sterilized at all times. In the absence of juvenile sterilization, 91% of adult intact females would need to be sterilized annually to halt population growth. In comparison, with a 3-year nonsurgical contraception program, an annual contraception rate of 60% of female juvenile and adult intact cats would be required to halt population growth, assuming that treated cats were retrapped at the same rate after 3 years.

There is an increasing demand for management of feral and wild carnivores; since many of them have become "pest species" by adapting successfully to changing environments, having substantial impacts on their prey species, and serving as reservoirs for infectious diseases. Also in captivity, a low adult mortality and an increase in longevity, especially in large carnivores, cause an urgent need for population management. This paper presents an overview on contraceptive strategies to control reproduction in carnivores. Factors that have to be considered before applying a certain method for fertility suppression are discussed. For birth control, several methods of hormonal chemosterilization, immunocontraception and pregnancy termination have been developed in domestic and captive exotic carnivores, but none of them are yet suitable for free-ranging animals. GnRH agonists, which suppress pituitary function very efficiently, are recommended in captive and domestic animals for reversible contraception. Immunological contraception, causing prolonged infertility after single application, is a promising approach for feral animals. However, a specific gamete or hormone-derived "self" antigen must be identified for each particular species.

The Humane Society of the United States estimates that each year between 8 and 10 million dogs and cats enter shelters and 4-5 million of these animals are euthanized due to lack of homes. Many veterinarians within the United States recommend surgical sterilization for population control in dogs and cats. However, there are non-surgical methods to control reproduction. Pharmacologic methods of contraception and sterilization can be safe, reliable and reversible. Hormonal treatments using progestins, androgens, or gonadotropin releasing hormone (GnRH) analogs act to either directly block reproductive hormone receptor-mediated events, or indirectly block conception via negative feedback mechanisms. Immunocontraception, via vaccination against GnRH, the luteinizing hormone receptor or zona pellucida proteins, is also possible. Intratesticular or intraepididymal injections provide a method for non-surgical sterilization of the male dog and cat. Additional methods have been employed for mechanical disruption of fertility including intravaginal and intrauterine devices and ultrasound testicular ablation. Alternative approaches to surgical sterilization will be reviewed.

Fertility control offers a potential alternative for controlling an abundance of wild ungulate populations where lethal methods are infeasible or unacceptable. A promising nonsteroidal, nonimmunologic approach to reversible contraception consists of agonist of gonadotropin-releasing hormone (GnRH). We evaluated the effects of the GnRH agonist, leuprolide, on reproduction, the suppression of luteinizing hormone (LH) and progesterone, blood parameters, and reproductive behavior in captive female mule deer (Odocoileus hemionus) during December 1999 through June 2001. Leuprolide, administered as a controlled release formulation (ATRIGEL), was 100% effective in preventing pregnancy for one breeding season. Infertility was achieved by suppressing LH levels, which prevented ovulation and the formation of corpus luteum. Treated females regained normal ovarian function and conceived the following breeding season. Leuprolide had no adverse effects on blood chemistry and hematology, body weight dynamics, or the general health of treated females. In contrast to our predictions, leuprolide did not suppress estrous behavior in female deer during the "normal" breeding period, nor did treated females return to normal ovarian function and exhibit reproductive behaviors during the post-breeding period. This prolonged-release leuprolide formulation offers an alternative approach to reversible contraception in female deer that overcomes some of the problems associated with existing technology.

As the next millennium approaches, the current world population of 5.9 billion will continue to increase by 81 million per year -- 93% of which will come from the developing countries. Poor uptake and utilisation of various modern methods of contraception in the developing countries is mainly responsible. In this article, we identify various barriers responsible for the low prevalence of contraceptive uptake in these countries and suggest how these barriers may be eliminated. We conclude that by increasing contraceptive availability and utilisation, population explosion can be significantly controlled.

A large variety of modern contraceptives is now available, including several means to administer hormonal contraception, highly effective long-term methods and simple sterilization techniques. Methods under research include immuno-contraceptives for women and men, hormonal methods for men, new approaches to female hormonal contraception and improved barrier methods. Modern contraceptives are effective and safe for most women, and some methods have beneficial health effects other than prevention of pregnancy. However, underlying health conditions may decrease the safety of a given method. The appropriate use of the technology available requires screening for biomedical conditions and counseling that enables the selection of methods according to the life style of women and couples. Contraceptive methods have had a considerable positive impact on maternal and infant health and on population growth, but unwanted pregnancies and unsafe abortion still occur in large numbers. This shows the need to improve access to and quality of family planning services including the availability of contraceptives, sensitive providers trained in technical matters and communication skills, and communication between the community, the providers and the managers.

This presentation reviews multiple wildlife health considerations associated with contraception of wildlife, at the level of both the individual animal and wildlife population. Review of the literature demonstrates that many contraceptives studied in the past have had potential adverse effects characterized as follows: harmful effects on pregnant animals, inhibition of parturition or dystocia, changes in ovarian structure or function, changes in sex ratio, changes in lactation or mammary glands, impact on fertility of young, changes in testicular structure or function, changes in secondary sex characteristics, changes in bodyweight, changes in behaviour, changes in annual breeding season, other physiologic and pathologic changes, abscesses or inflammatory reactions, toxicity, interference with diagnostic tests and ecological alterations. Concern is expressed that the use of immunocontraception could create genetic changes in the target population that would influence disease resistance. The use of infectious agents as vectors to deliver immunocontraceptives was not considered wise animal health management because the product will be a new reproductive disease that could be difficult to contain within the target population. Criteria that need to be fulfilled for the safe use of contraceptives in wildlife are offered.

Experimental studies demonstrating the effectiveness of nonclinical distribution of contraceptives are typically conducted in settings where contraceptive use is low and unmet need is extensive. Determining the long-term role of active outreach programs after initial demand is met represents an increasingly important policy issue in Asia, where contraceptive prevalence is high and fixed service points are conveniently available. This article examines the long-term rationale for household family planning in Bangladesh-where growing use of contraceptives, rapid fertility decline, and normative change in reproductive preferences are in progress, bringing into question the rationale for large-scale deployment of paid outreach workers. Longitudinal data are analyzed that record outreach encounters and contraceptive use dynamics in a large rural population. Findings demonstrate that outreach has a continuing impact on program effectiveness, even after a decade of household visitation. The policy implications of this finding are reviewed.