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OBJECTIVE: To develop, describe, and evaluate 2 surgical techniques for contraception of free-ranging female capybaras. STUDY DESIGN: Prospective study. ANIMALS: Cadaveric (n = 3) and free-ranging female capybaras (n = 21). METHODS: Preliminary studies of surgical anatomy were performed on 3 capybara cadavers. Two different techniques for partial salpingectomy were evaluated in free-ranging female capybaras: bilateral minilaparotomy (LTG; n = 11) or bilateral laparoscopy (LCG; n = 10). Data concerning body weight, tubal ligation time, total surgical time, incision size, and intraoperative and postoperative complications were analyzed, as well as the clinical status and incisional healing 1 week postoperatively. RESULTS: Body weight (P = .214), ligation time of the left uterine tube (P = .901), and total surgical time (P = .473) were similar between the experimental groups. The ligation time of the right uterine tube was shorter in the LCG group (P = .0463). In the LTG, no differences were observed between the sides regarding the incision size (P = .478). No major intraoperative or postoperative complications occurred in either group. One LCG procedure had to be converted to LTG due to technical issues. All skin incisions healed without complication. CONCLUSION: Both procedures showed similar and satisfactory outcomes. CLINICAL SIGNIFICANCE: The proposed techniques may be a suitable alternative to conventional laparotomy for contraception of female capybaras, especially under field conditions.

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In the feline species, progestins, GnRH agonist implants and melatonin implants are the three main non-surgical contraceptive approaches that are important to discuss today. When available, those can actually come handy in many clinical situations when surgery cannot be performed or should be avoided. To date though, those only offer short to medium term options. Research using gene therapy is however on its way, with encouraging preliminary results. A long term alternative using this technology might become available in the future, changing how we approach contraception in cats in our veterinary clinics.

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In this study, we determined the main reproductive parameters of piau gordura, Leporinus piau, in two sections of the São Francisco River basin. Between May 2015 and April 2016, a total of 573 specimens were captured from a lentic environment (section 1), the Três Marias Reservoir (TMR), and a lotic environment (section 2), downstream of the TMR at the confluence of the São Francisco River (SFR) with the Abaeté River. Analysis of reproductive activity showed that L. piau from both sections reproduced, but females and males from section 1 exhibited higher total length, body weight, Fulton condition factor, and gonadosomatic index values, as compared to section 2. Sexual dimorphism was evident in the species, with females being larger than males. Moreover, males reached first gonadal maturation at a smaller size than females. The peak maturation/mature stage was observed in November/April for females and males in section 1 and in November/December in section 2, coinciding with high temperatures and precipitation in the region. In both sections of the river, L. piau exhibited the typical characteristics of partial spawning, with a prolonged spawning period, and preferential reproduction in lentic environments.(AU)

Neste estudo, determinamos os principais parâmetros reprodutivos do piau gordura, Leporinus piau, em duas seções da bacia do rio São Francisco. Entre maio de 2015 e abril de 2016, um total de 573 espécimes foram capturados de um ambiente lêntico (seção 1), o reservatório de Três Marias (RTM), e um ambiente lótico (seção 2), à jusante da RTM na confluência do rio São Francisco (RSF) com o rio Abaeté. A análise da atividade reprodutiva mostrou que L. piau se reproduz nas duas seções, mas fêmeas e machos da seção 1 apresentaram maiores valores de comprimento total, peso corporal, fator de condição de Fulton e índice gonadossomático em comparação com a seção 2. O dimorfismo sexual foi evidente na espécie com as fêmeas sendo maiores do que os machos. Além disso, os machos atingiram a primeira maturação gonadal em tamanho menor do que as fêmeas. O pico do estágio de maturação/maduro foi observado em novembro/abril para fêmeas e machos na seção 1 e em novembro/dezembro na seção 2, coincidindo com altas temperaturas e precipitação na região. Em ambas as seções do rio, L. piau apresentou características típicas de desova parcelada com período de desova prolongada e reproduz preferencialmente em ambientes lênticos.(AU)

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RESUMEN

In this study, we determined the main reproductive parameters of piau gordura, Leporinus piau, in two sections of the São Francisco River basin. Between May 2015 and April 2016, a total of 573 specimens were captured from a lentic environment (section 1), the Três Marias Reservoir (TMR), and a lotic environment (section 2), downstream of the TMR at the confluence of the São Francisco River (SFR) with the Abaeté River. Analysis of reproductive activity showed that L. piau from both sections reproduced, but females and males from section 1 exhibited higher total length, body weight, Fulton condition factor, and gonadosomatic index values, as compared to section 2. Sexual dimorphism was evident in the species, with females being larger than males. Moreover, males reached first gonadal maturation at a smaller size than females. The peak maturation/mature stage was observed in November/April for females and males in section 1 and in November/December in section 2, coinciding with high temperatures and precipitation in the region. In both sections of the river, L. piau exhibited the typical characteristics of partial spawning, with a prolonged spawning period, and preferential reproduction in lentic environments.(AU)

Neste estudo, determinamos os principais parâmetros reprodutivos do piau gordura, Leporinus piau, em duas seções da bacia do rio São Francisco. Entre maio de 2015 e abril de 2016, um total de 573 espécimes foram capturados de um ambiente lêntico (seção 1), o reservatório de Três Marias (RTM), e um ambiente lótico (seção 2), à jusante da RTM na confluência do rio São Francisco (RSF) com o rio Abaeté. A análise da atividade reprodutiva mostrou que L. piau se reproduz nas duas seções, mas fêmeas e machos da seção 1 apresentaram maiores valores de comprimento total, peso corporal, fator de condição de Fulton e índice gonadossomático em comparação com a seção 2. O dimorfismo sexual foi evidente na espécie com as fêmeas sendo maiores do que os machos. Além disso, os machos atingiram a primeira maturação gonadal em tamanho menor do que as fêmeas. O pico do estágio de maturação/maduro foi observado em novembro/abril para fêmeas e machos na seção 1 e em novembro/dezembro na seção 2, coincidindo com altas temperaturas e precipitação na região. Em ambas as seções do rio, L. piau apresentou características típicas de desova parcelada com período de desova prolongada e reproduz preferencialmente em ambientes lênticos.(AU)

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To test the hypothesis that postnatal sexual steroids induce an impairment of domestic male cat reproductive function, this study describes the physical, endocrine, steroidogenical and histological effects of a single, high dose of a postnatal sexual steroid in this species. Twenty male kittens were randomly assigned within the first 24 h of birth to: Testosterone enanthate 12.5 mg sc (TE; n = 8), medroxyprogesterone acetate 10 mg sc (MA; n = 6), or Placebo sc (PL; n = 6). The cats were followed until puberty when they were castrated. Kittens achieved puberty without age differences among groups (P > 0.05). Two MA cats presented abnormal testicular descent. Histological evaluation of the MA (P < 0.01), but not of TE testes revealed decreased diameter (P < 0.01) and epithelial height (P < 0.01) of the seminiferous tubules. Leydig cell nuclear area was also reduced in this group. Conversely, tubular/intertubular ratio was increased in TE animals (P < 0.01). Quantitative real-time PCR analysis of mRNA expression of testicular tissue revealed no significant differences among groups for StAR, CYP17A1 and androgen receptors. TE animals showed decreased CYP19A1 mRNA expression (P < 0.05). In the first 4 postnatal weeks, fecal testosterone (T) values were high, basal and intermediate in TE, MA and PL (P < 0.05), respectively. These differences progressively diminished and the three groups presented basal T concentrations from the 7th week on (P > 0.05). It was concluded that the postnatal progestagen initially suppressed the gonadal axis and caused an impairment of spermatogenesis and testicular descent at puberty. Androgen treatment caused downregulation of the final steroidogenic cascade.

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O convívio entre humanos e animais a exemplo da presença do cão junto ao ser humano existe desde épocas longínquas. Devidoa este estreito contato muitas doenças se difundem entre os homens, transmitidas através de animais infectados as denominadas zoonoses. A Educação Ambiental é uma alternativa para se desenvolver a conscientização da população, buscando promover a guarda-responsável, o bem-estar animal e a redução dos casos de doenças zoonóticas. Dentro deste contexto, como presente trabalho objetivou-se analisar o nível de conhecimento da população da Rua Carlos Gomes de Alencar, município de Várzea Alegre, Ceará, sobre zoonoses. Esta abordagem foi feita através de entrevistas com a aplicação de um questionário. Os resultados demonstraram que os entrevistados, possuem um precário entendimento sobre o assunto em questão, e que por isso estão expostos a zoonoses, por se encontrarem em áreas de risco.

The interaction between humans and animals and especially the presence of the dog along to humans has been known since remote times, and due to this close contact many diseases are spread among men, transmitted through infected animals are called zoonoses. Environmental education is an alternative to develop public awareness, seeking to promote the guard -responsible, well -being of animals and reducing cases of zoonotic diseases. Within this context, this study aimed to analyze the level of knowledge of the population of street Carlos Gomes de Alencar, municipality of Várzea Alegre, Ceará, on zoonoses. This approach was made through interviews with the application of a questionnaire. The results showed that the respondents have a poor understanding of the subject matter, and therefore are exposed to diseases, because they are in risk areas.

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O convívio entre humanos e animais a exemplo da presença do cão junto ao ser humano existe desde épocas longínquas. Devidoa este estreito contato muitas doenças se difundem entre os homens, transmitidas através de animais infectados as denominadas zoonoses. A Educação Ambiental é uma alternativa para se desenvolver a conscientização da população, buscando promover a guarda-responsável, o bem-estar animal e a redução dos casos de doenças zoonóticas. Dentro deste contexto, como presente trabalho objetivou-se analisar o nível de conhecimento da população da Rua Carlos Gomes de Alencar, município de Várzea Alegre, Ceará, sobre zoonoses. Esta abordagem foi feita através de entrevistas com a aplicação de um questionário. Os resultados demonstraram que os entrevistados, possuem um precário entendimento sobre o assunto em questão, e que por isso estão expostos a zoonoses, por se encontrarem em áreas de risco.(AU)

The interaction between humans and animals and especially the presence of the dog along to humans has been known since remote times, and due to this close contact many diseases are spread among men, transmitted through infected animals are called zoonoses. Environmental education is an alternative to develop public awareness, seeking to promote the guard -responsible, well -being of animals and reducing cases of zoonotic diseases. Within this context, this study aimed to analyze the level of knowledge of the population of street Carlos Gomes de Alencar, municipality of Várzea Alegre, Ceará, on zoonoses. This approach was made through interviews with the application of a questionnaire. The results showed that the respondents have a poor understanding of the subject matter, and therefore are exposed to diseases, because they are in risk areas.(AU)

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The objective of this study was to assess the efficiency and clinical safety of postnatal administration of a GnRH agonist on canine puberty postponement. Sexual steroids and histological gonadal changes were also described. Twenty-four littermate puppies were randomly assigned to: Deslorelin acetate 18.8 mg sc (DESLO; n = 12) or Placebo: sc (PLACE; n = 12) postnatally. The dogs were clinically and endocrinologically followed up until puberty when they were gonadectomized and their gonads histomorphometrically studied. Deslorelin postponed the age of puberty (72.7 ±â€¯4.8 vs. 35.8 ±â€¯1.9 weeks; P < 0.01) in these dogs. At the time of this submission, 3 DESLO dogs (108 weeks old) remain non-pubertal. All dogs concluded growing at a similar age (29.75 ±â€¯2.44 vs. 29.25 ±â€¯0.90 weeks; P > 0.1) independently of their group and pubertal status. None of the females had side effects while the 2 non pubertal DESLO males presented bilateral cryptorchydism. All the bitches ovulated at puberty (P > 0.1) and the 2 DESLO that were mated became pregnant. Deslorelin postponed basal serum sexual steroids up to puberty in both genders (P < 0.01). The histomorphometrical study of the testes revealed that the tubular diameter (P < 0.05), germinal epithelium height and composition (P < 0.01) were decreased in DESLO group. Ovarian structures did not differ between treatments (P > 0.05). It was concluded that postnatal deslorelin decreased sexual steroids reversibly postponing puberty in both genders without side effects in bitches and causing 2/6 of cryptorchydism and impairment of testicular histomorphometry in male dogs.

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Human-wildlife conflicts, a growing and sad reality worldwide, makes population control of wildlife and feral animals one of the biggest challenges in wildlife management, especially due to the rapidly expanding human population, and consequently the ever-diminishing natural habitats of animals. Human activities and the destruction of nature forcing wildlife to move inevitably into urban and agricultural areas, causing "conflicts", such as the risk of zoonosis and traffic accidents, as well as damage to crops in the search for food, whose losses reach millions of dollars. For decades, science has been engaged in extensive efforts to develop methods of "humane" population control methods, and many techniques are being employed in order to control wildlife population. In this article, we present an overview of applied contraceptive methods with simplified graphic demonstrations of their interactions with reproductive physiology, furthermore relating pro and contra of utilized antifertility agents. These are being compared to a set of desired characteristics for free-ranging wildlife for in-field applications, with emphasis on reversible immunocontraception ­ concluding, therefore, the reasons why this concept is becoming the most appropriate and promising for free-ranging wildlife.(AU)

Os conflitos Humanos-Animais Selvagens são uma realidade crescente e triste no mundo inteiro, tornando o controle populacional da fauna silvestre e animais ferais o maior desafio, principalmente diante do crescimento da população humana e, consequentemente, da diminuição dos habitats naturais dos animais. As atividades humanas e a destruição da natureza, forçam os animais de vida livre a se dirigirem para áreas urbanas e agrícolas, inevitavelmente, causando conflitos, como o risco de zoonoses, acidentes de trânsito, bem como danos às plantações, quando em busca de alimentos, cujo prejuízo chega a milhões de dólares. Durante décadas, a ciência esteve empenhada em esforços extensivos para desenvolver métodos de controle populacional "humano"; e muitas técnicas foram utilizadas, a fim de se realizar um controle populacional destes animais silvestres. Neste artigo será apresentada uma visão geral dos métodos anticoncepcionais aplicados, com demonstrações gráficas simplificadas de suas interações com a fisiologia reprodutiva, bem como relacionando os prós e os contras dos agentes antifertilidade empregados; também serão comparados com um conjunto de características desejadas para as aplicações em fauna a campo, com ênfase em imunocontracepção reversível, concluindo assim, com as razões do porque este conceito torna-se o mais apropriado e promissor para animais silvestres de vida livre.(AU)

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Human-wildlife conflicts, a growing and sad reality worldwide, makes population control of wildlife and feral animals one of the biggest challenges in wildlife management, especially due to the rapidly expanding human population, and consequently the ever-diminishing natural habitats of animals. Human activities and the destruction of nature forcing wildlife to move inevitably into urban and agricultural areas, causing "conflicts", such as the risk of zoonosis and traffic accidents, as well as damage to crops in the search for food, whose losses reach millions of dollars. For decades, science has been engaged in extensive efforts to develop methods of "humane" population control methods, and many techniques are being employed in order to control wildlife population. In this article, we present an overview of applied contraceptive methods with simplified graphic demonstrations of their interactions with reproductive physiology, furthermore relating pro and contra of utilized antifertility agents. These are being compared to a set of desired characteristics for free-ranging wildlife for in-field applications, with emphasis on reversible immunocontraception ­ concluding, therefore, the reasons why this concept is becoming the most appropriate and promising for free-ranging wildlife.(AU)

Os conflitos Humanos-Animais Selvagens são uma realidade crescente e triste no mundo inteiro, tornando o controle populacional da fauna silvestre e animais ferais o maior desafio, principalmente diante do crescimento da população humana e, consequentemente, da diminuição dos habitats naturais dos animais. As atividades humanas e a destruição da natureza, forçam os animais de vida livre a se dirigirem para áreas urbanas e agrícolas, inevitavelmente, causando conflitos, como o risco de zoonoses, acidentes de trânsito, bem como danos às plantações, quando em busca de alimentos, cujo prejuízo chega a milhões de dólares. Durante décadas, a ciência esteve empenhada em esforços extensivos para desenvolver métodos de controle populacional "humano"; e muitas técnicas foram utilizadas, a fim de se realizar um controle populacional destes animais silvestres. Neste artigo será apresentada uma visão geral dos métodos anticoncepcionais aplicados, com demonstrações gráficas simplificadas de suas interações com a fisiologia reprodutiva, bem como relacionando os prós e os contras dos agentes antifertilidade empregados; também serão comparados com um conjunto de características desejadas para as aplicações em fauna a campo, com ênfase em imunocontracepção reversível, concluindo assim, com as razões do porque este conceito torna-se o mais apropriado e promissor para animais silvestres de vida livre.(AU)

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A população de gatos domésticos já excede a de cães em muitos países do mundo e o crescimentopopulacional dos gatos domésticos domiciliados cresce paralelamente ao da população de animais abandonados.Esse fato nos coloca frente a uma problemática referente a procriação excessiva e a todas as consequênciasrelativas a essa situação. A escolha de métodos contraceptivos adequados para a espécie felina ainda necessitamde experimentos controlados e de observações a longo prazo para a determinação das vantagens e desvantagensde determinados procedimentos e do conhecimento dos mecanismos de ação de fármacos com indicaçãocontraceptiva. A proposta dessa revisão de literatura é abordar os contraceptivos mais utilizados nos felinosdomésticos, enfatizando o mecanismo de ação, dosagens utilizadas, vantagens e desvantagens de cada fármacoconsiderado.

The number of domestic cats already exceeds dog population in many countries around the world. Alsothe number of housed cats grows in the same scale of abandoned animals. This fact makes us face the problem ofexcessive procreation and all consequences related this issue. The choice of an appropriated contraceptivemethod for felines still needs controlled experiments and long term observations in order to determine all prosand cons of some procedures and to increase the knowledge regarding the action mechanism of drugs that mayact as contraceptive. This review objective is to approach the most used contraceptive treatments in domesticfelines, emphasizing the action mechanism, recommended dosage, pros and cons from each contraceptivemethods.

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A população de gatos domésticos já excede a de cães em muitos países do mundo e o crescimentopopulacional dos gatos domésticos domiciliados cresce paralelamente ao da população de animais abandonados.Esse fato nos coloca frente a uma problemática referente a procriação excessiva e a todas as consequênciasrelativas a essa situação. A escolha de métodos contraceptivos adequados para a espécie felina ainda necessitamde experimentos controlados e de observações a longo prazo para a determinação das vantagens e desvantagensde determinados procedimentos e do conhecimento dos mecanismos de ação de fármacos com indicaçãocontraceptiva. A proposta dessa revisão de literatura é abordar os contraceptivos mais utilizados nos felinosdomésticos, enfatizando o mecanismo de ação, dosagens utilizadas, vantagens e desvantagens de cada fármacoconsiderado.(AU)

The number of domestic cats already exceeds dog population in many countries around the world. Alsothe number of housed cats grows in the same scale of abandoned animals. This fact makes us face the problem ofexcessive procreation and all consequences related this issue. The choice of an appropriated contraceptivemethod for felines still needs controlled experiments and long term observations in order to determine all prosand cons of some procedures and to increase the knowledge regarding the action mechanism of drugs that mayact as contraceptive. This review objective is to approach the most used contraceptive treatments in domesticfelines, emphasizing the action mechanism, recommended dosage, pros and cons from each contraceptivemethods.(AU)

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A ovulação em gatas é induzida por um reflexo neuroendócrino atribuído à estimulação mecânica dos receptores sensoriais durante o coito. Esta estimulação pode ser simulada com auxílio do swab vaginal, desencadeando a pseudogestação. Objetivou-se verificar a eficiência da indução de ovulação com swab, a fim de estabelecer um tratamento contraceptivo natural para felinos domésticos, bem como os efeitos sobre o útero do uso repetido dessa técnica. Na primeira fase do trabalho, foram avaliados 12 animais em três ciclos estrais consecutivos. No primeiro ciclo (T1), houve estimulação vaginal com swab. No segundo ciclo (T2), foi utilizado macho vasectomizado para cópula. No último ciclo (T3), a ovulação foi acompanhada sem estímulo (controle). Na segunda etapa do trabalho, 13 gatas foram submetidas a sucessivos estados de pseudogestação com intuito de verificar os efeitos da estimulação mecânica sobre o útero. A confirmação da ovulação em todas as etapas do trabalho foi realizada por meio da mensuração dos níveis de progesterona. A estimulação vaginal com swab apresentou resposta similar à obtida por monta natural (P>0,05). Algumas gatas apresentaram modificações uterinas discretas; no entanto, nenhum desses achados foi considerado de relevância patológica. Desta forma, a indução de ovulação com swab mostrou-se segura e sem efeitos colaterais expressivos.

A neuroendocrine reflex attributed to the mechanical stimulation of sensory receptors during copulation induces ovulation in cats. This stimulation can be simulated with a vaginal swab, triggering pseudopregnancy. The efficiency of ovulation induction with swab was evaluated in order to establish a natural contraceptive treatment for domestic cats as well as to analyze the effect on uterus of the repeated use of this technique. At the first phase of the study, 12 animals were evaluated in three consecutive estrous cycles. In the first cycle (T1), vaginal swab stimulation was applied. In the second cycle (T2), a vasectomized male was used. In the third cycle (T3), ovulation was accompanied unstimulated (control). At the second phase of the study, 13 female cats were induced to successive pseudopregnancy states to check the effects on the uterus. Confirmation of ovulation in the two phases of the study was carried out by measuring progesterone serum levels. The vaginal swab stimulation showed a similar response to that obtained by natural mating (P>0.05). Some cats showed mild uterine changes without pathological relevance. Thus, ovulation induction with swab is secure and without significant side effects.

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A ovulação em gatas é induzida por um reflexo neuroendócrino atribuído à estimulação mecânica dos receptores sensoriais durante o coito. Esta estimulação pode ser simulada com auxílio do swab vaginal, desencadeando a pseudogestação. Objetivou-se verificar a eficiência da indução de ovulação com swab, a fim de estabelecer um tratamento contraceptivo natural para felinos domésticos, bem como os efeitos sobre o útero do uso repetido dessa técnica. Na primeira fase do trabalho, foram avaliados 12 animais em três ciclos estrais consecutivos. No primeiro ciclo (T1), houve estimulação vaginal com swab. No segundo ciclo (T2), foi utilizado macho vasectomizado para cópula. No último ciclo (T3), a ovulação foi acompanhada sem estímulo (controle). Na segunda etapa do trabalho, 13 gatas foram submetidas a sucessivos estados de pseudogestação com intuito de verificar os efeitos da estimulação mecânica sobre o útero. A confirmação da ovulação em todas as etapas do trabalho foi realizada por meio da mensuração dos níveis de progesterona. A estimulação vaginal com swab apresentou resposta similar à obtida por monta natural (P>0,05). Algumas gatas apresentaram modificações uterinas discretas; no entanto, nenhum desses achados foi considerado de relevância patológica. Desta forma, a indução de ovulação com swab mostrou-se segura e sem efeitos colaterais expressivos.(AU)

A neuroendocrine reflex attributed to the mechanical stimulation of sensory receptors during copulation induces ovulation in cats. This stimulation can be simulated with a vaginal swab, triggering pseudopregnancy. The efficiency of ovulation induction with swab was evaluated in order to establish a natural contraceptive treatment for domestic cats as well as to analyze the effect on uterus of the repeated use of this technique. At the first phase of the study, 12 animals were evaluated in three consecutive estrous cycles. In the first cycle (T1), vaginal swab stimulation was applied. In the second cycle (T2), a vasectomized male was used. In the third cycle (T3), ovulation was accompanied unstimulated (control). At the second phase of the study, 13 female cats were induced to successive pseudopregnancy states to check the effects on the uterus. Confirmation of ovulation in the two phases of the study was carried out by measuring progesterone serum levels. The vaginal swab stimulation showed a similar response to that obtained by natural mating (P>0.05). Some cats showed mild uterine changes without pathological relevance. Thus, ovulation induction with swab is secure and without significant side effects.(AU)

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Abstract Lutjanid species exhibit multiple spawning behaviour during an extended spawning season in warm months, asynchronous oocyte development and indeterminate fecundity. Although early studies have contributed to knowledge of the reproductive cycle of many species within the group, they have not considered aspects about the number of cortical alveoli oocyte stage throughout maturity phases along spawning season. The latter aspect is also considered very important to confirm indeterminate fecundity hypothesis. In the present study, were analyzed 154 Brazilian snapper Lutjanus alexandrei female gonads obtained from artisanal fisheries in Pernambuco State (Brazil) between October 2010 and March 2011. Were measured oocyte size frequency distribution for maturity phases (developing, spawning capable and actively spawning), and oocyte development stage (unyolked oocytes, cortical alveoli, primary, secondary and tertiary vitellogenic oocytes and hydrated oocytes), and also the oocyte stage frequency during spawning season. The frequency of cortical alveoli oocyte stage was constantly found in the spawning period (>37%), showing slight variation throughout maturity phases. The absence of gap in the oocyte size frequency distribution between primary and secondary oocyte growth stages during spawning season is a strong indicator of continuous oocyte recruitment from reserve stocks. In addition, co-occurrence of tertiary vitellogenic oocytes, hydrated oocytes, post-ovulatory follicles and yellow-brown bodies in the histological sections of ovaries reinforce indeterminate fecundity hypothesis.(AU)

Resumo Os lutjanídeos apresentam um comportamento de desovas parceladas ao longo de uma extensa estação reprodutiva nos meses mais quentes do ano, desenvolvimento assincrônico dos ovócitos e padrão de regulação de fecundidade indeterminado. Embora muitos estudos anteriores tenham contribuído no conhecimento do ciclo reprodutivo das espécies do grupo, não foram considerados os aspectos relacionados ao percentual dos ovócitos em estágio de cortical alveoli entre as fases de maturidade sexual durante a estação reprodutiva. Este último aspecto, considerado importante para confirmação da hipótese de fecundidade do tipo indeterminada. Para isso, no presente trabalho foram analisadas 154 gônadas de fêmeas da baúna de fogo Lutjanus alexandrei obtidas da pesca artesanal em Pernambuco entre o período de outubro de 2010 a março de 2011. Foram mensurados os diâmetros dos ovócitos nas fases de maturidade sexual (desenvolvimento, capaz de desovar e ativamente desovando), e para todos os estágios ovocitários (ovócitos pre-vitelogênicos, cortical alveolar, vitelogênese primária, secundária, terciária e ovócitos hidratados), e avaliada a frequência de ocorrência ao longo do período de desova. O percentual de ovócitos em estágio cortical alveoli permaneceu constante durante o período de reprodutivo (> 37%), apresentando pouca variação entre as fases de maturidade sexual. A ausência de um intervalo na frequência de diâmetro dos ovócitos em crescimento primário e secundário entre todas as fases de maturidade sexual é um forte indicador de recrutamento contínuo de ovócitos do estoque de reserva. Além disso, a presença conjunta de ovócitos em vitelogênese terciária, ovócitos hidratados, folículos pós-ovulatórios e corpos amarelados nos cortes histológicos reforçam a hipótese de fecundidade do tipo indeterminada.(AU)

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Background: Dog fertility depends on human-influenced factors such as sterilization. Uncontrolled fertility can result in unwanted births and overpopulation, which causes problems of public health and animal welfare. Surgical sterilization has been the traditional means of reproduction control but its cost and time can be prohibitive for mass sterilization programs. Non-surgical sterilization alternatives exist, but most of them are reversible and their effectiveness as a population management tool is unknown. To better understand the consequences of reversible contraception, the fertility dynamics was modeled in a hypothetical dog population in a steady-state condition.Materials, Methods & Results: The effect of reversible contraception was simulated using a coupled system of ordinary differential equations. A hypothetical steady-state population of 1000 animals was considered. It was formed by two compartments, one of fertile dogs and the other of infertile dogs. Natality compensated for a fraction of mortality, and the immigration rate compensated for the remaining fraction. The group of immigrant dogs was composed of fertile and infertile dogs. The dog flow between compartments was given by both the contraception and fertility recovery rate. It was assumed that fertility reversibility in animals of the immigrant group was equal to that of animals already present in the [...]

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RESUMEN

Background: Dog fertility depends on human-influenced factors such as sterilization. Uncontrolled fertility can result in unwanted births and overpopulation, which causes problems of public health and animal welfare. Surgical sterilization has been the traditional means of reproduction control but its cost and time can be prohibitive for mass sterilization programs. Non-surgical sterilization alternatives exist, but most of them are reversible and their effectiveness as a population management tool is unknown. To better understand the consequences of reversible contraception, the fertility dynamics was modeled in a hypothetical dog population in a steady-state condition.Materials, Methods & Results: The effect of reversible contraception was simulated using a coupled system of ordinary differential equations. A hypothetical steady-state population of 1000 animals was considered. It was formed by two compartments, one of fertile dogs and the other of infertile dogs. Natality compensated for a fraction of mortality, and the immigration rate compensated for the remaining fraction. The group of immigrant dogs was composed of fertile and infertile dogs. The dog flow between compartments was given by both the contraception and fertility recovery rate. It was assumed that fertility reversibility in animals of the immigrant group was equal to that of animals already present in the [...](AU)

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In postnatal domestic cats, GnRH agonists suppressed fecal concentrations of sexual steroids and delayed puberty. The aim of this study was to describe the gross and microscopic morphometric effects of a single administration of the GnRH agonist, deslorelin acetate, on the gonads of postnatally treated cats. Twenty-seven postnatal male (n = 14) and female (n = 13) kittens were randomly assigned to one of the following treatment groups within the first 24 hours of birth: deslorelin acetate (1.6 mg, subcutaneous; DA, n = 16) or control that remained untreated (CO, n = 11) and spayed or castrated immediately after the onset of puberty. After surgical removal, the gonads were gross and histologically assessed. Sertoli cells also were examined immunohistochemically. Comparisons between the treatments were carried out by the Student t test. Gross gonadal wet weight and volume as well as gonadosomatic index were significantly lower in the DA than those in the CO males; these same parameters were not different in females. Primordial (461.4 + 3.0 vs. 1074.3 + 117.5; P < 0.01), primary (59.1 + 13.5 vs. 165.4 + 24.6; P < 0.01), and secondary (17.5 + 2.6 vs. 31.17 + 8.1; P < 0.05) follicles per mm(2) were decreased in DA than in CO gonads. Epididymal sperm motility and morphology were normal in all but two DA cats that had too few sperm to be evaluated. Germinal epithelial height (µm; 39.68 + 0.92 vs. 72.7 + 1.2; P < 0.01) and most of their cellular components as well as the Sertoli (cm(3); 0.1 + 0.02 vs. 0.24 + 0.05; P < 0.01) cells were diminished in the DA cats. Gonadotropin-releasing hormone agonist endocrine disruption during the neonatal critical reproductive time window may have a potential as a contraceptive agent in domestic felids.

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