Infertility in bitches and queens: recent advances / Infertilidade na cadela e gata: atualidades

In comparison to the last 10 or 20 years, veterinarians are now frequently requested to solve fertility problems in the dog and cat, mainly due to the increased popularity of purebred dogs as well as for sentimental or financial reasons. Infertility in dogs and cats can be due to wrong breeding management, uterine disease, ovarian disease, failure of the male to achieve a complete mount, or poor semen quality. From a practical standpoint, fertility means achieving conception, then establishing a pregnancy through implantation and carrying the pregnancy to term.

Comparando-se os últimos 10 - 20 anos, os veterinários têm sido freqüentemente procurados para resolver problemas de fertilidade na cadela e gata, principalmente devido ao aumento da popularidade das raças puras, bem como por questões sentimentais ou ainda por razões financeiras. Do ponto de vista prático, fertilidade significa atingir a concepção, estabelecer uma gestação e levar a mesma a termo. A infertilidade em cadelas e gatas pode estar relacionada com erros no manejo da cobertura, doenças uterinas e/ou ovarianas, falha do macho em realizar a monta completa ou devida á qualidade insatisfatória do sêmen.

The use of GnRH agonists implants in bitches and queens / Utilização de implantes de agonistas do GnRH em cadelas e gatas

GnRH (gonadotrophin releasing hormone) is a key hormone of reproductive function in mammals; agonist forms have been largely developed, and data concerning their use in small animal reproduction are now abundant. GnRH agonists act by a two-step mechanism. First, their agonist properties on the pituitary will cause marked LH (luteinizing hormone) and FSH (follicle-stimulating hormone) secretion into the bloodstream, accompanied by an increase in the concentrations of sex steroid hormones. Then, in case of constant administration, GnRH agonists will lead to pituitary desensitization, and FSH and LH levels will collapse. These two effects have been widely documented, and these compounds have many potential benefits in a clinical context, capitalizing both on their stimulating and sterilizing effects.

O hormônio liberador de gonadotrofinas (GnRH) é um hormônio chave na função reprodutiva dos mamíferos. Formas agonistas têm sido amplamente desenvolvidas e atualmente existem muitas informações sobre sua utilização na reprodução de pequenos animais. Os agonistas do GnRH atuam por meio de um mecanismo que envolve duas etapas. Inicialmente, suas propriedades agonistas irão causar secreção marcante de hormônio luteinizante (LH) e folículo-estimulante (FSH) pela hipófise, acompanhado pelo aumento das concentrações dos hormônios esteróides sexuais. Em seguida, no caso de administração contínua, os agonistas do GnRH irão causar dessensibilização e as concentrações de LH e FSH irão declinar. Estes dois efeitos já foram amplamente discutidos e estes compostos possuem vários benefícios no contexto clínico, devido aos às suas características estimulantes e contraceptivas.

Infertility in male dogs: recent advances / Infertilidade do macho canino: atualidades

Very little is known about male infertility in the dog. The causes of infertility are divided into two main groups, congenital infertility and acquired infertility. Congenital infertility is caused by genetic (chromosomal) abnormalities and is present at birth. Acquired infertility develops during the dog's lifetime. Infertility in male dogs is diagnosed by a good medical history, including breeding management, and a physical examination.

Pouco se sabe sobre as causas da infertilidade do macho canino. As causas de infertilidade são divididas em dois grupos principais, quais sejam alterações congênitas ou adquiridas. As alterações congênitas são causadas por anormalidades genéticas (cromossomais) e estão presentes ao nascimento. As alterações adquiridas, por sua vez, acontecem no decorrer da vida do animal. A infertilidade do macho canino é diagnosticada por meio de um bom histórico, incluindo manejo de cobertura e exame físico.

L’insémination artificielle chez les félidés / Artificial insemination in felids / Inseminação artificial em felídeos

L’insémination artificielle chez le chat domestique et les félidés sauvages répond à plusieurs indications. Chez le chat, elle peut notamment permettre d’aider la reproduction lorsque l’accouplement ne se produit pas ou difficilement et de favoriser les échanges géographiques de semence et donc un brassage et une meilleure sélection génétiques. Chez les félins sauvages, elle joue un rôle complémentaire au sein des programmes de conservation. Son utilisation est cependant complexe. L’oestrus et l’ovulation sont le plus souvent induits par l’emploi de gonadotropines qui possèdent cependant des effets indésirables, notamment un risque d’hyperstimulation ovarienne. La semence des mâles est généralement récoltée par électro-éjaculation. Elle peut être congelée. Néanmoins, un problème spécifique aux félins tient à la tératospermie, c'est-à-dire la production de nombreux spermatozoïdes porteurs d’anomalies morphologiques. L’insémination artificielle donne de meilleurs résultats lorsque la semence est déposée par voie intra-utérine. Pendant longtemps, la laparoscopie a été la technique de référence, mais récemment, des techniques de cathétérisme du col utérin par voie vaginale ont été mises au point, aussi bien chez le chat que chez certains félidés sauvages. Les résultats de l’insémination artificielle chez les félidés restent moyens.

Artificial insemination in the domestic cat and in wild felids has several indications. In the cat, it may replace natural reproduction when matings are unsuccessful or difficult, and it may help to perform geographical exchanges of semen and therefore enhance genetic improvement. In wild felids, it plays a complementary role inside conservation programs. However, its use is complex. First, oestrus and ovulation have to be induced. This is most often obtained using gonadotrophins, which unfortunately may induce undesirable effects, like ovarian hyperstimulation. In males, the semen is generally collected by electro-ejaculation. It may be frozen. However, teratospermia, which is the production of numerous spermatozoa showing morphological abnormalities, is a specific problem affecting felids. Intrauterine inseminations give better results. For a long period, laparoscopy was recommended in felids to perform intrauterine inseminations. Recently, new techniques consisting of catheterizing the cervix through a vaginal access have been developed in the cat as in some wild felids species. Altogether, the rate of success of artificial insemination in felids remains moderate.

A inseminação artificial em gatos domésticos e felídeos tem várias indicações. No gato, esta técnica substitui a reprodução natural quando as coberturas são mal sucedidas ou de difícil realização, além disso, auxilia geograficamente na permuta de sêmen contribuindo para aumentar a qualidade genética. Nos felídeos selvagens, esta técnica desempenha um papel complementar nos programas de conservação. Contudo, sua utilização é complexa. Inicialmente, há necessidade da indução do estro e ovulação. Geralmente isto é obtido por meio da utilização de gonadotrofinas que, infelizmente, induz a alguns efeitos indesejáveis, tais como, hiperestimulação ovariana. Nos machos, o sêmen geralmente é coletado por meio de eletroejaculação e este é submetido à congelaçãoAdicionalmente, a teratospermia, que é a produção de um grande número de espermatozóides com anormalidades morfológicas, é um problema específico que afeta os felídeos. Melhores resultados são obtidos com a inseminação intrauterina. Durante muito tempo recomendava-se a laparoscopia para a realização da inseminação intrauterina em felídeos. Recentemente, novas técnicas que consistem na cateterização da cérvix através do canal vaginal foram desenvolvidas no gato e em algumas espécies de felídeos selvagens. De modo geral, o índice de sucesso da inseminação artificial em felídeos ainda é considerado modesto.

Linsémination artificielle chez les félidés / Artificial insemination in felids / Inseminação artificial em felídeos

Linsémination artificielle chez le chat domestique et les félidés sauvages répond à plusieurs indications. Chez le chat, elle peut notamment permettre daider la reproduction lorsque laccouplement ne se produit pas ou difficilement et de favoriser les échanges géographiques de semence et donc un brassage et une meilleure sélection génétiques. Chez les félins sauvages, elle joue un rôle complémentaire au sein des programmes de conservation. Son utilisation est cependant complexe. Loestrus et lovulation sont le plus souvent induits par lemploi de gonadotropines qui possèdent cependant des effets indésirables, notamment un risque dhyperstimulation ovarienne. La semence des mâles est généralement récoltée par électro-éjaculation. Elle peut être congelée. Néanmoins, un problème spécifique aux félins tient à la tératospermie, c'est-à-dire la production de nombreux spermatozoïdes porteurs danomalies morphologiques. Linsémination artificielle donne de meilleurs résultats lorsque la semence est déposée par voie intra-utérine. Pendant longtemps, la laparoscopie a été la technique de référence, mais récemment, des techniques de cathétérisme du col utérin par voie vaginale ont été mises au point, aussi bien chez le chat que chez certains félidés sauvages. Les résultats de linsémination artificielle chez les félidés restent moyens.(AU)

Artificial insemination in the domestic cat and in wild felids has several indications. In the cat, it may replace natural reproduction when matings are unsuccessful or difficult, and it may help to perform geographical exchanges of semen and therefore enhance genetic improvement. In wild felids, it plays a complementary role inside conservation programs. However, its use is complex. First, oestrus and ovulation have to be induced. This is most often obtained using gonadotrophins, which unfortunately may induce undesirable effects, like ovarian hyperstimulation. In males, the semen is generally collected by electro-ejaculation. It may be frozen. However, teratospermia, which is the production of numerous spermatozoa showing morphological abnormalities, is a specific problem affecting felids. Intrauterine inseminations give better results. For a long period, laparoscopy was recommended in felids to perform intrauterine inseminations. Recently, new techniques consisting of catheterizing the cervix through a vaginal access have been developed in the cat as in some wild felids species. Altogether, the rate of success of artificial insemination in felids remains moderate.(AU)

A inseminação artificial em gatos domésticos e felídeos tem várias indicações. No gato, esta técnica substitui a reprodução natural quando as coberturas são mal sucedidas ou de difícil realização, além disso, auxilia geograficamente na permuta de sêmen contribuindo para aumentar a qualidade genética. Nos felídeos selvagens, esta técnica desempenha um papel complementar nos programas de conservação. Contudo, sua utilização é complexa. Inicialmente, há necessidade da indução do estro e ovulação. Geralmente isto é obtido por meio da utilização de gonadotrofinas que, infelizmente, induz a alguns efeitos indesejáveis, tais como, hiperestimulação ovariana. Nos machos, o sêmen geralmente é coletado por meio de eletroejaculação e este é submetido à congelaçãoAdicionalmente, a teratospermia, que é a produção de um grande número de espermatozóides com anormalidades morfológicas, é um problema específico que afeta os felídeos. Melhores resultados são obtidos com a inseminação intrauterina. Durante muito tempo recomendava-se a laparoscopia para a realização da inseminação intrauterina em felídeos. Recentemente, novas técnicas que consistem na cateterização da cérvix através do canal vaginal foram desenvolvidas no gato e em algumas espécies de felídeos selvagens. De modo geral, o índice de sucesso da inseminação artificial em felídeos ainda é considerado modesto.(AU)

Infertility in male dogs: recent advances / Infertilidade do macho canino: atualidades

Very little is known about male infertility in the dog. The causes of infertility are divided into two main groups, congenital infertility and acquired infertility. Congenital infertility is caused by genetic (chromosomal) abnormalities and is present at birth. Acquired infertility develops during the dog's lifetime. Infertility in male dogs is diagnosed by a good medical history, including breeding management, and a physical examination.(AU)

Pouco se sabe sobre as causas da infertilidade do macho canino. As causas de infertilidade são divididas em dois grupos principais, quais sejam alterações congênitas ou adquiridas. As alterações congênitas são causadas por anormalidades genéticas (cromossomais) e estão presentes ao nascimento. As alterações adquiridas, por sua vez, acontecem no decorrer da vida do animal. A infertilidade do macho canino é diagnosticada por meio de um bom histórico, incluindo manejo de cobertura e exame físico.(AU)

The use of GnRH agonists implants in bitches and queens / Utilização de implantes de agonistas do GnRH em cadelas e gatas

GnRH (gonadotrophin releasing hormone) is a key hormone of reproductive function in mammals; agonist forms have been largely developed, and data concerning their use in small animal reproduction are now abundant. GnRH agonists act by a two-step mechanism. First, their agonist properties on the pituitary will cause marked LH (luteinizing hormone) and FSH (follicle-stimulating hormone) secretion into the bloodstream, accompanied by an increase in the concentrations of sex steroid hormones. Then, in case of constant administration, GnRH agonists will lead to pituitary desensitization, and FSH and LH levels will collapse. These two effects have been widely documented, and these compounds have many potential benefits in a clinical context, capitalizing both on their stimulating and sterilizing effects.(AU)

O hormônio liberador de gonadotrofinas (GnRH) é um hormônio chave na função reprodutiva dos mamíferos. Formas agonistas têm sido amplamente desenvolvidas e atualmente existem muitas informações sobre sua utilização na reprodução de pequenos animais. Os agonistas do GnRH atuam por meio de um mecanismo que envolve duas etapas. Inicialmente, suas propriedades agonistas irão causar secreção marcante de hormônio luteinizante (LH) e folículo-estimulante (FSH) pela hipófise, acompanhado pelo aumento das concentrações dos hormônios esteróides sexuais. Em seguida, no caso de administração contínua, os agonistas do GnRH irão causar dessensibilização e as concentrações de LH e FSH irão declinar. Estes dois efeitos já foram amplamente discutidos e estes compostos possuem vários benefícios no contexto clínico, devido aos às suas características estimulantes e contraceptivas.(AU)

Infertility in bitches and queens: recent advances / Infertilidade na cadela e gata: atualidades

In comparison to the last 10 or 20 years, veterinarians are now frequently requested to solve fertility problems in the dog and cat, mainly due to the increased popularity of purebred dogs as well as for sentimental or financial reasons. Infertility in dogs and cats can be due to wrong breeding management, uterine disease, ovarian disease, failure of the male to achieve a complete mount, or poor semen quality. From a practical standpoint, fertility means achieving conception, then establishing a pregnancy through implantation and carrying the pregnancy to term.(AU)

Comparando-se os últimos 10 - 20 anos, os veterinários têm sido freqüentemente procurados para resolver problemas de fertilidade na cadela e gata, principalmente devido ao aumento da popularidade das raças puras, bem como por questões sentimentais ou ainda por razões financeiras. Do ponto de vista prático, fertilidade significa atingir a concepção, estabelecer uma gestação e levar a mesma a termo. A infertilidade em cadelas e gatas pode estar relacionada com erros no manejo da cobertura, doenças uterinas e/ou ovarianas, falha do macho em realizar a monta completa ou devida á qualidade insatisfatória do sêmen.(AU)

[Risk factors for multiple intestinal parasites in an indigenous community of the State of Pernambuco, Brazil]. / Fatores de risco para poliparasitismo intestinal em uma comunidade indígena de Pernambuco, Brasil.

An investigation into the ethno-epidemiological profile of the Pankararu indigenous group in the State of Pernambuco, Brazil, identified multiple intestinal parasites in nearly all members of the community. To detect possible environmental risk factors, we used the data base from a previous survey to test relations between daily living conditions (housing, sanitation, water supply and treatment, and garbage disposal) and the number of different parasite species found in the same household. The sample consisted of 84 families from the original sample of 112. Selection was based on the number of stool tests performed in the family. The mean number of parasite species was 5.0 per family, for a mean family size of 6.1 members. This number was greater for wattle-and-daub houses (mean 6.0 parasite species vs. 4.9 for brick houses; p < 0.03) and when water used in the household was not treated (mean 5.1 parasite species, vs. 4.5 for treated water; p < 0.05). Other household characteristics and hygienic habits did not significantly influence this number. We concluded that multiple intestinal parasitism in the Pernambuco Pankararu community is frequent, to the point of being the rule, and that it relates essentially to water source and treatment.

Socio-medical intervention in occupational health: benzenism in Brazil.

This review describes the authors' experience with 2,000 cases of benzene poisoning reported between 1983 and 1995 in Cubatão, an industrial section of São Paulo, Brazil, investigated through the integration of epidemiology and clinical research. Conflicting economic interests were reflected in disputes about medical criteria for evaluation of poisoned workers, about proper means of conducting workplace hygiene evaluations, about benzene exposure standards, and about compensation for chronic bone-marrow damage.

Insulin-resistance syndrome and cardiovascular complications of non-insulin-dependent diabetes mellitus.

Although most cohort studies have shown that diabetes is a risk factor for cardiovascular disease, the mechanisms remain unclear. Hyperglycaemia defines this disorder but does not provide the criteria for causality. However, there are new indications for the possible role of a potentially atherogenic and diabetogenic syndrome rooted in insulin resistance, which was first described by Reaven as "syndrome X". In its complete form, this syndrome includes hyperinsulinaemia, glucose intolerance, dyslipidaemia, elevated blood pressure and fibrinolytic impairment. The complex pathophysiological processes leading to the clustering of these abnormalities are still unclear but probably relate to excessive intra-abdominal fat deposits (clinically expressed by upper body fet distribution) and combined insulin resistance and hyper-insulinaemia. The presence of insulin resistance and hyperinsulinaemia in pre-diabetic individuals, and their predictive role in non-insulin dependent diabetes mellitus, has been documented in various ethnic groups, suggesting a two-step process in the natural history of the disease, i.e. "compensated" insulin resistance followed by failure of insulin secretory response leading to a hyperglycaemic (diabetic) phase. In Caucasians at least, in whom the insulin-resistance syndrome includes clear abnormalities in its most potentially atherogenic elements, this natural history suggests that the cardiovascular complications associated with non-insulin dependent diabetes mellitus originate from the initial "pre-diabetic" phase of the disease. Early prevention would theoretically require intervention before hyperglycaemia occurs (or even if it will never occur) for all upper body obese subjects who present with insulin-resistance syndrome.

Features of insulin-resistance syndrome in men from French Caribbean Islands. The Telecom Study.

The prevalence of diabetes is known to be high in the West Indies, whereas CVD seems relatively rare. This apparently contradicts the existence of the insulin-resistance syndrome, a cluster of metabolic abnormalities supposedly favoring both diabetes and cardiovascular complications. To address the question of whether this contradiction could be accounted for by specific features of this syndrome, we compared 1505 Caucasian and 181 Afro-Caribbean men, all participants in the French Telecom Study. The Afro-Caribbeans were of the same age and had the same BMI as the Caucasians; they also had significantly higher subscapular skin-fold thickness and fasting insulin level, but similar BP and blood glucose level, and significantly lower plasma triglyceride level. Thus, although some features of the insulin-resistance syndrome were present (central adiposity and high insulin levels), none of the associated metabolic abnormalities were present. However, within the Afro-Caribbean group, subjects with plasma insulin concentrations above the median (> 52 pM) had higher mean BP and glucose and triglyceride levels compared with subjects with insulin concentrations < or = 52 pM (P < 0.001). After adjustment for age and BMI, these differences, though smaller, still were statistically significant. These findings confirm that higher insulin concentrations are associated with higher levels of potentially atherogenic and diabetogenic metabolic parameters. However, depending on ethnic origin, the mean levels of these parameters seem to be different, with the consequence that, even if they are elevated with increasing insulin levels, they may not reach values high enough to determine a substantial risk of disease.