Brazilian Spotted Fever Prevention through a Nonlethal Capybara Population Control Strategy

Rosenfield, Derek Andrew; Polo, Gina; Pizzutto, Cristiane Schilbach

doi:10.1590/0037-8682-0156-2019

Cited by 5 publications

(5 citation statements)

References 12 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this sense, the re‐establishment of the connectivity among native natural areas in human‐modified landscapes, mediated by ecological restoration, might help reinstate at least some of the natural balance by providing access routes to predators (pumas, caimans), for example. Another possibility to reduce the number of individuals, in particular cases, is to perform contraceptive methods such as vasectomy in males or tubal ligation in females, or through immunocontraception, a less invasive method (Rosenfield et al, 2019). All the results presented here, together with the behavioral plasticity of the species, help in explaining the resilience of the capybara in surviving and thriving in both favorable and unfavorable conditions along with its distribution, in natural or human‐modified environments.…”

Section: Discussionmentioning

confidence: 99%

Plasticity in resource use explains the persistence of the largest living rodent in anthropized environments

et al. 2023

View full text Add to dashboard Cite

How organisms search for and obtain food is a determinant of their survival. It has been hypothesized that organisms facing food limitations might expand their dietary niche compared with optimal foraging conditions. Nonetheless, some organisms may reduce their dietary niche due to limiting resources. Here, we show the resource use plasticity of capybaras (Hydrochoerus hydrochaeris), the largest living rodent, in natural and anthropized environments of Brazil using stable carbon and nitrogen isotopes in hair. We assessed the resource use, size and overlap of isotopic niches, and the influence of body mass, age class, sex, and landscape composition on isotopic values among 13 capybara populations (210 individuals). We observed a wide variation in isotopic values of capybaras among and within populations in different environments. Surprisingly, diets varied from strictly C4‐based to strictly C3‐based, with most individuals feeding on C4 plants (65%). A substantial portion of individuals presented mixed diets (C3 and C4 plants), totaling 31% of the individuals, and few fed exclusively on C3 plants (4%). Isotopic niche size also varied among populations in both environments, with low overlap considering their core dietary niche. Capybara populations in natural environments had substantial incorporation of C3 resources, showing individuals with strictly C3 diets, and possibly relying on a high diversity of food items, while some populations in anthropized ones fed exclusively on C4 resources. Neither body mass, age class, sex, nor landscape composition significantly influenced isotopic values. Here, we provide evidence of the dietary plasticity of capybaras in different environments, transitioning from the consumption of C4 to C3 plants when needed, that is, from preferred to non‐preferred food items. Together with the species' behavioral plasticity, our results help explain its resilience in surviving, and even thriving, in both natural and human‐modified environments.

show abstract

Section: Discussionmentioning

confidence: 99%

Plasticity in resource use explains the persistence of the largest living rodent in anthropized environments

et al. 2023

View full text Add to dashboard Cite

show abstract

“…Immunocontraceptive vaccines have been proposed as an effective contraceptive strategy for male capybaras, preserving the alpha male's social behavior ( Rosenfield & Pizzutto, 2019 ), with the benefit of being less invasive ( Rosenfield et al, 2019a ) and also being a strategy for BSF control ( Rosenfield et al, 2019c ).…”

Section: Discussionmentioning

confidence: 99%

Surgical sterilization of free-ranging capybaras (Hydrochoerus hydrochaeris): “Passos Nunes” uterine horn ligature

Nunes¹,

Jorge

Nunes³

et al. 2022

Anim. Reprod.

Self Cite

View full text Add to dashboard Cite

Capybaras are the primary hosts of Amblyomma sculptum tick, vectors of Rickettsia rickettsia bacteria, and the zoonotic agent of Brazilian Spotted Fever (BSF). In this context, contraceptive methods have been suggested for population control in order to reduce the number of free-ranging capybaras cohabiting with humans in urban and rural areas and acting as disease amplifiers. To maintain the group's expected behavior and social hierarchy, sterilization techniques that preserve the gonads are recommended. On 126 female capybaras in the Brazilian state of São Paulo, a new surgical technique named “Passos Nunes” uterine horn ligature was performed after adequate general anesthesia. It achieved effective surgical sterilization, with an incision length of about 3 cm in the periumbilical linea alba, cranial to the pubis. After entering the abdominal cavity, the urinary bladder is pulled laterally to access the uterine horns and the cervix. The uterine horn is folded up, forming a strap; the distal portion of the strap is ligated and its distal end sectioned. The exact process is performed on the opposite horn. After the surgical procedure, the musculature is sutured in a sultan pattern and the subcutaneous tissue with a horizontal mattress pattern. The skin is sutured in a separate simple format, using nylon 2.0 for all steps. The wide exposure of the uterine horns facilitates the confirmation of pregnancy, allowing the surgeon to choose between salpingo hysterectomy or ligature of the uterine horns. The present study presents a new technique of surgical sterilization that can be used in female free-ranging mammals in which maintenance of the gonads is recommended, and births of offspring should not occur.

show abstract

“…Associating management practices for capybaras in areas that are endemic for BSF with quality of life for this species is challenging, since these practices must be effective given the risk imposed to public health. The stochastic model proposed by POLO et al (2017) andROSENFIELD et al (2019b) demonstrated how strategies to control and prevent the transmission of infectious diseases by vectors can be focused on management practices towards amplifying hosts. This showed that actions should be directed towards the capybaras and that important effort has been underway in the planning of reproductive control programs.…”

Section: Discussionmentioning

confidence: 99%

“…Strategies to decrease capybara populations through contraceptive methods reduce their capacity to carry and transport ticks, and mostly important, reduce the number of newborns that could act as amplifying hosts through their primary infection by R. rickettsii (POLO et al, 2017;ROSENFIELD et al, 2019b;ROSENFIELD et al, 2019c). Hence, any method that decreases capybara reproduction in a BSF-endemic area can be an effective alternative to control the disease.…”

Section: Microbiologymentioning

confidence: 99%

Reproductive control of capybaras through sterilization in areas at risk of transmission of brazilian spotted fever

Nunes

Nunes²,

Nunes³

et al. 2020

Cienc. Rural

Self Cite

View full text Add to dashboard Cite

Groups of capybaras (Hydrochoerus hydrochaeris) are currently frequent inhabitants of urban areas. The species participates in the transmission cycle of Brazilian spotted fever (BSF), a zoonosis that is caused by the bacteria R. rickettsii and transmitted by vector ticks. This has led to discussions on strategies to decrease the presence of this rodent through contraceptive methods and euthanasia, thus reducing their capacity to carry and transport ticks, which would be an important contribution to public health. Two condominiums and one business establishment in the interior of the state of São Paulo were used as case studies in the present investigation. All areas were classified by the Endemic Control Superintendence as risk areas for the transmission of BSF and presented the specie of ticks A. sculptum and A. dubitatum The objective of this study was to carry out sterilization procedures with animals that presented seropositive results for BSF. A total of 85 surgical procedures were conducted on immune capybaras, with authorization from DeFau/SMA-SP. For all procedures the animals were anesthetized with ketamine hydrochloride combined with xylazine and morphine. Two alpha males isolated themselves from the group after the vasectomy procedure, returning to their hierarchical position after 5 to 14 days. Population monitoring in the areas should be maintained indefinitely and conducting annual serological management until the natural death of these individuals. Tubal ligation, vasectomy and salpingo-oophorectomy were demonstrated to be simple and low-risk procedures in capybaras. These techniques assist in the population control of this species in enclosed areas with risk of BSF transmission, thus decreasing the need for euthanasia.

show abstract

Brazilian Spotted Fever Prevention through a Nonlethal Capybara Population Control Strategy

Cited by 5 publications

References 12 publications

Plasticity in resource use explains the persistence of the largest living rodent in anthropized environments

Plasticity in resource use explains the persistence of the largest living rodent in anthropized environments

Surgical sterilization of free-ranging capybaras (Hydrochoerus hydrochaeris): “Passos Nunes” uterine horn ligature

Reproductive control of capybaras through sterilization in areas at risk of transmission of brazilian spotted fever

Contact Info

Product

Resources

About