The behavioral responses of lynx (Lynx canadensis) to declines in snowshoe hare (Lepus americanus) abundance were examined in the southwestern Yukon. Between April 1982 and June 1984 11 lynx were radio-tagged and monitored within and near the Kluane Game Sanctuary. Lynx mean home range size increased from 13.2 to 39.2 km² concurrent with a decline in snowshoe hare abundance from 14.7 to 0.2 hares/ha. Below about 0.5 hares/ha several lynx abandoned their home ranges and became nomadic, although they remained within the general study area. Track transects through areas known to have different snowshoe hare densities indicated that, lynx concentrated their foraging efforts in areas of relatively high snowshoe hare abundance. Lynx abandoned these areas after hare abundance declined. Lynx foraging effort in terms of distance travelled per day showed a curvilinear relationship to snowshoe hare abundance. Straight-line daily travel distance remained constant at 2.2 to 2.7 km/day above 1.0 hare/ha. Below 1.0 hares/ha, straight-line daily travel distances increased rapidly, reaching 5.5 km/day at 0.2 hares/ha. Three of 7 radio-tagged lynx dispersed 250 km or more from the study area during the period of rapid decline in hare abundance in 1982. No similar long distance dispersal was recorded after hare densities stabilized at less than 1.0 hares/ha. Trapping mortality was responsible for the loss of 7 of 9 radio-tagged lynx that travelled outside the game sanctuary. One lynx died, and is believed to have starved, during the winter or spring of 1984. The high rate of trapping mortality outside the game sanctuary suggests that refugia in wilderness areas are important in maintaining lynx populations during periods of low recruitment. / Science, Faculty of / Zoology, Department of / Graduate

Depression affects approximately 7% of adults in the US annually and is one of the most common mental disorders. One striking aspect of this disorder, is that it affects women at about twice the rate as compared to men. Furthermore, women with cardiovascular diseases are more likely to experience depression as compared to male counterparts. Thus, women with cardiovascular complications represent an extremely vulnerable population for mood disorder. Given the disparity in depression prevalence, it is not surprising that women are also more likely to take antidepressant treatments as compared to men. While the dose of the antidepressant prescribed is similar across the board, there is mounting evidence that the efficacy of and sensitivity to these treatments differ between the sexes. However, the majority of preclinical investigations into the effectiveness and biochemical mechanisms of antidepressants have been conducted in male subjects. This is a serious gap in our knowledge, and investigations into the mechanisms underlying differences in depression prevalence and antidepressant response is imperative. As such, this dissertation aimed to identify potential peripheral and neural changes associated with onset of depression in females with cardiovascular disease, and to examine the neural mechanisms underlying the sex differences in sensitivity to antidepressants. There is substantial evidence that depression is experienced at a much higher rate in individuals with chronic conditions, such as cardiovascular disease. Within this population, women with cardiovascular diseases represent an extremely vulnerable population for mood disorder, comorbid for these conditions at about twice the rate as compared to men. Despite the well-established comorbidity, the mechanisms linking these disorders remain elusive. The first chapter of this dissertation aimed to identify the expression of core behavioral features of mood disorder in female mice bearing a knock-in sarcomeric mutation, which is exhibited in human hypertrophic cardiomyopathy (HCM). We then investigated peripheral physiological indicators of stress in these mice, and discovered significant adrenal gland hypertrophy and a dominant sympathetic nervous system tone. Through the use of magnetic resonance imaging, we found reduced volume in mood-related brain regions in females with HCM. We also observed significant reductions in hippocampal neurotrophic signaling markers in females with HCM as compared to controls. These results suggest that prolonged systemic HCM stress is central to mood disorder expression; possibly through induction of structural and functional brain changes. In direct contrast to the negative impact of stress/depression on the structure and function of the brain, many antidepressants reverse these changes and promote neurogenesis. In recent years, ketamine has shown great promise as an antidepressant. A single infusion can exert effects within hours of treatment, and this rapid action is a unique feature of ketamine. Most antidepressants need to be taken for weeks to months to exert therapeutic effects, and often the first medication prescribed is not effective. Ketamine represents a great advancement in the field, especially for individuals suffering from depression and cardiovascular dysfunction. In this population, the use of ketamine could circumvent the potential for negative interactions between cardiac medications and chronic antidepressants. Since females are more likely to take antidepressants as compared to males, we wanted to examine how the males and females differed in behavioral and neurochemical responses to ketamine. Our group and others have previously reported that female rodents are more sensitive to the antidepressant-like effect of ketamine. There is some evidence that ovarian hormones may promote sensitivity to antidepressants, yet the precise molecular mechanism of females’ heightened sensitivity to ketamine remains unclear. In order to fill these critical gaps in our knowledge, the second chapter of this dissertation aimed to determine the role of endogenous ovarian hormones and their respective receptor subtypes to promote ketamine sensitivity. Behavioral responses to ketamine were examined in males, females in diestrus 1 (D1, low hormone), and females in proestrus (Pro, high hormone) using the forced swim test. Males and D1 females exhibited similar sensitivity, while Pro females responded to doses of ketamine that were subthreshold for effects in male and D1 counterparts. Through the use of selective estrogen receptor modulators (SERMS), we examined the role of estrogen receptor subtypes (ERα and ERβ) and progesterone receptors (PR) to promote ketamine sensitivity. We found that D1 females treated with ERα and ERβ SERMS responded to ketamine treatment, which suggests that estrogen action at these receptors may enhance ketamine sensitivity. Another aim of chapter two was to determine if the molecular mechanisms previously shown to mediate ketamine’s antidepressant effects in male rodents also apply to females. Since many of the rapid intracellular signaling cascades initiated by ketamine are also influenced by ovarian hormones (e.g., brain-derived neurotrophic factor), we used Western blot to investigate the expression and activation of their shared targets. We confirmed previous reports in males that ketamine activated a variety of neurotrophic signaling cascades in the prefrontal cortex and hippocampus, and extended them to include D1 and Pro females. As a first step towards identifying the neural mechanism of Pro females’ sensitivity, we found that these females exhibited activation of Akt and CaMKIIα in response to a dose of ketamine that only they were sensitive to. While these results need to be confirmed in vivo, together they suggest that ovarian hormones increase behavioral sensitivity to ketamine by enhancing ketamine’s effects on PI3K and CaMKIIα signaling within mood-related brain regions. These studies examined the expression and molecular mechanisms of mood disorder-like behaviors in a mouse model of cardiovascular dysfunction. We focused on females with HCM, since they represent an especially vulnerable population for mood disorder. We also investigated the hormonal and biochemical contributors to sex differences in sensitivity to ketamine. This work lays a foundation for future investigation of the effectiveness of ketamine to reverse depression-associated features in females with HCM. By targeting the natural flux in ovarian hormones, it may be possible to safely and effectively treat these females with a low dose of ketamine. / A Dissertation submitted to the Department of Biomedical Sciences in partial fulfillment of the Doctor of Philosophy. / Fall Semester 2016. / November 21, 2016. / Depression, Diastolic Dysfunction, Estrogen, Hypertrophy Cardiomyopathy, Ketamine, Sex differences / Includes bibliographical references. / Mohamed Kabbaj, Professor Directing Dissertation; Thomas C. S. Keller, University Representative; Elaine M. Hull, Committee Member; Jose R. Pinto, Committee Member; Zuoxin X. Wang, Committee Member.

<p>    </p> <p>In honey bees, male fertility is directly involved in colony fitness. Males not only provide fifty percent of colony genetics, but they also provide material benefits involved with female fertility. Recent evidence suggests there is tremendous variation in drone fertility. Of drones which are sexually mature, as few as one in ten may be able to produce enough sperm to successfully inseminate a queen. If drones are not producing healthy sperm, their mates will not produce healthy colonies. Despite this, we have very little understanding of precisely how variation in drone reproductive quality is generated. Specifically, we know comparatively little about the role genetics plays in shaping drone reproductive traits. This standing genetic variation can contribute to phenotypic variation observed among honey bee stocks and contribute to the success (or failure) of colonies. <strong>The major goal of this thesis is to identify the major mechanisms and genes driving genotypic and phenotypic variation in honey bee males. </strong>First, we used a population genetics approach to estimate the evolutionary impact of haploid selection <strong>(Chapter 2) </strong>and variation in sexual selection <strong>(Chapter 3) </strong>on male genes. In <strong>Chapter 2</strong>, we found genes expressed by males had an increased genetic diversity, rate of adaptation, and more efficient purifying selection than non-haploid selected female-expression genes. This suggests haploid and sexually- expressed genes experience increases in the rate of molecular evolution. In <strong>Chapter 3</strong>, we found selection on sperm length shifted over evolutionary time within corbiculate bees, resulting in different strengths of sexual selection. As selection for sperm length intensified in male bees, there was rapid evolution of expression patterns and gene sequences associated with male-biased genes. Second, we used a quantitative genetics approach to connect genetic variation to the trait components of fitness <strong>(Chapter 4)</strong>. We identified key genes connected to honey bee male sperm and maturity traits. These genes also appear to have different rates of evolution. Overall, we combined both population and quantitative genetic approaches to provide comprehensive insights into the evolution of honey bee male genotypes and phenotypes. This powerful approach allowed me to identify the genetic and mechanistic underpinnings driving variation in fitness-related traits. This information can be used to identify candidate genes associated with honey bee male fitness. </p>

O objetivo deste trabalho foi determinar e avaliar os fatores sanitários e reprodutivos capazes de afetar a produtividade de vacas leiteiras. Pesquisou-se por meio de dois estudos correlacionais os efeitos de ocorrências sanitárias no periparto e seus respectivos fatores de risco sobre a produção de leite no pico e aos 305 dias em lactação, e os fatores de riscos para falhas na concepção ao primeiro serviço pós-parto (CPS). Para concretizar o objetivo deste trabalho, foram coletados mensalmente durante os anos de 2001 e 2002 dados de um rebanho comercial de vacas leiteiras de raça holandesa, localizado no Estado de São Paulo. Para a realização do primeiro estudo foram usadas 15.613 observações e para a análise estatística dos dados foram utilizadas a regressão logística e a análise de regressão múltipla. Os resultados obtidos nestas análises demonstraram que as doenças do periparto e seus fatores de risco afetaram a produção de leite com diferentes efeitos em função do número de lactações, exigindo desta maneira maior cuidado com adoção de medidas profiláticas para serem evitadas doenças e para maximizar a produção de leite dos animais. Foram usadas no segundo estudo 13.594 observações e os dados foram analisados estatisticamente por meio de regressão logística, calculando-se a razão das chances no isolamento dos fatores de risco e na associação entre os riscos para sucesso ou falha na CPS. Os resultados obtidos indicaram que os principais fatores de risco foram o número da lactação, a época do ano ao primeiro serviço, a ocorrência de doenças no periparto, a relação entre as porcentagens de gordura e proteína do leite (RGP) e as alterações no escore de condição corporal (ECC). Os animais de primeira lactação apresentaram maior chance de sucesso ao primeiro serviço do que os animais multíparos. As vacas cobertas no período do inverno apresentaram, aproximadamente, cinco vezes mais chances de CPS do que as vacas cobertas no verão. Os animais que apresentaram doenças no periparto tiveram menor sucesso de concepção que os animais sadios. Os animais que apresentaram melhor condição ruminal, determinada pela RGP, principalmente durante o período de verão, tiveram melhor concepção do que os animais com RGP reduzida no verão. O ECC adequado nas diferentes fases produtivas das vacas (secagem, parto e cobertura) demonstrou ser uma importante ferramenta para identificar as vacas com risco de insucesso na concepção ao primeiro serviço. / These studies evaluate health and reproductive factors affecting dairy cows’ productivity. Through correlation studies were evaluated health occurrences and risk factors during peripartum for milk production at peak, after 305 days of lactation and conception failures on first service pos-partum (CFS). Using a commercial herd of "dairy holsteins cows" located in São Paulo state - Brazil, data were collect in 2001 and 2002. On the first study were used 15,613 observations, the statistical analyses data were processed on logistic regression and multiple regression analyses. The analyses showed that peripartum diseases and risk factors directly affected milk production, with different effects based on lactations times, requesting extra care on prophylactics to avoid diseases and improve milk production. On the second study were used 13,594 observations, the statistical analyses data were processed on logistic regression calculating chances ratio on risk factors isolation and risk factors association to success or failure on first service pos-partum. Results indicated as mainly risks factors: lactation times, year period that first service occurred, peripartum diseases, body score condition (BSC), milk protein and fat ratio (PFR). First lactation animals presented more chance of success to the first service than multiparous. Cows inseminated during winter time showed 5 times more chances of CFS than ones inseminated on summer time. Animals with peripartum diseases had less conception success than healthy ones. Cows with better rumminal condition (FPR) had a much better conception than ones with lower FPR. The correct BSC on different productive steps (dry-off, calving and breeding) showed to be an important tool to identify animals with higher risks of failure on first service conception.

Várias doenças músculo esqueléticas foram observadas em aves de rápido crescimento, sendo o elevado peso corporal, associado a uma estrutura óssea em formação, citados como as principais causas responsáveis pela ocorrência destas doenças, resultando em disfunções do aparelho locomotor. Apesar do estudo do membro pélvico do avestruz merecer a atenção de pesquisadores desde o século XIX, tendo sido descrito no tocante à miologia, principalmente, a osteologia e o estudo radiográfico e morfológico envolvidos na RTT ainda não receberam a devida atenção. O presente trabalho teve como objetivo fazer um estudo anátomo-patológico e radiográfico das estruturas envolvidas na rotação tibiotársica, assim como estudar as alterações articulares através de artrografias e histologia fazendo uma descrição das considerações anatômicas, macroscópicas, microscópicas e radiográficas do membro pélvico do avestruz (African Black). Para este estudo foram utilizadas trinta avestruzes, com idade entre um mês a um ano de idade, apresentando deformidade de membros pélvicos uni ou bilateral. Dessa forma, será possível contribuir para o entendimento desta enfermidade, que tem causado perdas para a estrutiocultura. / Ostrich?s hind limbs study: Anatomical, radiographic and histological considerations of the tibiotarsus rotation. Many skeletal muscles diseases were observed in fast growth, been the hight body wight, to associate with a bone structure in formation citads with the principal responsible cases for ocorrence these deseases, have been disfunction of locomotor arrangment. Despite the fact that the ostrich?s hind limbs have deserved attention from researchers since the 19th century, the myological and osteological descriptions together with the radiographic and morphological study, which involves RTT, have not received any attention yet. This present research intends to make an anatomical, pathological and radiographic study of the structures involved in the tibiotarsus rotation, besides the study of the joint alterations by arthrography and histology, giving one description with anatomical, macroscopic, microscopic and radiographic considerations of the ostrich?s hind limbs. This way, it?ll be possible to contribute to the comprehension of this disease that has caused many losses on the ostrich farm.

O lagarto teiú Salvator merianae pertence à família TEIIDAE, são animais forrageadores ativos e alimentam-se principalmente de insetos quando filhotes, e onívoros quando jovens e adultos. Na região sudeste do Brasil S. merianae apresenta um ciclo anual de atividade durante o verão e inatividade durante o inverno, assim, estudar esse modelo de animal é de extrema importância, pois, se trata de uma espécie que obedece a um ciclo de ajustes fisiológicos distintos que podem influenciar a taxa de turnover e o fator de discriminação isotópico. Foram coletados dados de 26 indivíduos juvenis e 11 adultos. A delta13C das células vermelhas inicial não apresentou diferença entre juvenis e adultos, no entanto para o plasma foram distintos. Essa diferença pode ter ocorrido porque a dieta ao longo de suas vidas não era homogênea. A delta15N das células vermelhas e do plasma foram distintos entre os juvenis e adultos. A diferença encontrada pode ser atribuída a modelos de balanço nitrogenado distintos. Foi apontado a comparação entre os períodos de pré-dormência e despertar da dormência sazonal, a fim de verificar se a utilização das reservas endógenas poderia influenciar os dados iniciais. A delta13C das células vermelhas dos juvenis e dos adultos não foram diferentes entre os períodos. Entretanto, a delta15N dos juvenis foi distinto e similar para os adultos. O plasma se comportou de forma similar as células vermelhas para a delta13C nos juvenis e adultos. Todavia o nitrogênio do plasma se anotou distintos, sendo o período de despertar enriquecido tanto para os juvenis como adultos. Desta forma, a espécie utilizou um misto da reserva lipídica e aminoácidos endógenos na produção de energia diante de uma taxa metabólica muito baixa. As taxas de turnover das células vermelhas para 13C e 15N dos juvenis e dos adultos foram 79,57 e 34,88 dias e 66,84 e 43,38 dias respectivamente, porém o plasma foi mais rápido sendo, 41,64 e 20,83 dias e 38,77 e 22,78 dias respectivamente. Os valores de Delta13C das células vermelhas dos juvenis e dos adultos 1,43? e 1,25 ?, e Delta13C do plasma apresentaram os valores de 2,10? e 1,87? na ordem. O do Delta15N das células vermelhas dos juvenis e dos adultos foram 3,05? e 3,44?, seguido dos valores de Delta15N do plasma 3,93? e 4,34?. Todos os valores não apontaram um padrão entre os táxons da literatura devido influências peculiares que podem ser intrínsecos entre as espécies. Houve uma correlação entre o índice de massa corpórea com o Delta13C do plasma dos juvenis e com os Delta13C das células vermelhas e plasma e Delta15N das células vermelhas dos adultos. Essa correlação parece estar relacionada com uma possível intolerância aos carboidratos provenientes da dieta. No entanto o Delta15N do plasma parece estra relacionado com a entrada de reserva endógena e o controle do catabolismo. Juvenis e adultos, machos e fêmeas mostraram semelhança em todas as comparações. Esse resultado era esperado porque no final do experimento os indivíduos juvenis se enquadravam em sub-adultos e a alocação para reprodução ter sua maior contribuição da fonte endógena. / The tegu lizard Salvator merianae belongs to the TEIIDAE family. They are active foraging animals that feed mainly on insects when cubs, becoming omnivores when they reach youth and adulthood. In the Southeastern of Brazil, S. merianae presents an annual cycle of activity during the summer and inactivity during the winter. Thereupon, studying this animal is extremely important, since it\'s a species that obeys a cycle of physiological adjustments which may influence the turnover rate and the isotopic discrimination factor. Data were collected from 26 juveniles and 11 adults. The delta13C of the red cells didn\'t present difference between juveniles and adults; however these values were different for plasma. This difference may have occurred because the diet throughout their lives was not homogeneous. The delta15N of red cells and plasma were distinct between juveniles and adults. The difference found can be attributed to different nitrogen balance models. It was pointed out the comparison between the periods of pre-dormancy and awakening of the seasonal dormancy, in order to verify if the use of the endogenous reserves could influence the initial data. The delta13C of the red cells of juveniles and adults was not different between periods. However, the delta15N of juveniles was distinct and similar for adults. Plasma behaved similarly to red cells for delta13C in juveniles and adults. Meanwhile, the nitrogen of plasma was distinct and the arousal period was enriched for both juveniles and adults. The species used a mixture of its own lipid reserves and endogenous amino acids for the energy production before a very low metabolic rate. Red cell turnover rates for 13C and 15N of juveniles and adults were 79.57 and 34.88 days and 66.84 and 43.38 days, respectively. Nonetheless, the plasma rate was faster as the values found were 41.64 and 20.83 days and 38.77 and 22.78 days. The Delta13C values of red cells for juveniles and adults were 1.43? and 1.25?, and the Delta13C values of plasma were 2.10? and 1.87? respectively. The Delta15N values of red cells for juveniles and adults were 3.05? and 3.44 ?, followed by Delta15N values of 3.93? and 4.34? for plasma. All values didn\'t indicate a pattern among the taxa due to peculiar influences that may be intrinsic among the species. There was a correlation between body mass index and Delta13C values for juvenile plasma and Delta13C of red cells and plasma, as well as Delta15N values for red cells in adults. This correlation seems to be related to a possible intolerance to dietary carbohydrates. However, the Delta15N of plasma appears to be related to endogenous reserve inflow and catabolism control. Juveniles and adults, males and females showed similarity in all comparisons. This result was expected because at the end of the experiment juveniles could be classified as sub-adults and the allocation for reproduction had its greatest contribution from the endogenous source

O objetivo deste trabalho foi determinar e avaliar os fatores sanitários e reprodutivos capazes de afetar a produtividade de vacas leiteiras. Pesquisou-se por meio de dois estudos correlacionais os efeitos de ocorrências sanitárias no periparto e seus respectivos fatores de risco sobre a produção de leite no pico e aos 305 dias em lactação, e os fatores de riscos para falhas na concepção ao primeiro serviço pós-parto (CPS). Para concretizar o objetivo deste trabalho, foram coletados mensalmente durante os anos de 2001 e 2002 dados de um rebanho comercial de vacas leiteiras de raça holandesa, localizado no Estado de São Paulo. Para a realização do primeiro estudo foram usadas 15.613 observações e para a análise estatística dos dados foram utilizadas a regressão logística e a análise de regressão múltipla. Os resultados obtidos nestas análises demonstraram que as doenças do periparto e seus fatores de risco afetaram a produção de leite com diferentes efeitos em função do número de lactações, exigindo desta maneira maior cuidado com adoção de medidas profiláticas para serem evitadas doenças e para maximizar a produção de leite dos animais. Foram usadas no segundo estudo 13.594 observações e os dados foram analisados estatisticamente por meio de regressão logística, calculando-se a razão das chances no isolamento dos fatores de risco e na associação entre os riscos para sucesso ou falha na CPS. Os resultados obtidos indicaram que os principais fatores de risco foram o número da lactação, a época do ano ao primeiro serviço, a ocorrência de doenças no periparto, a relação entre as porcentagens de gordura e proteína do leite (RGP) e as alterações no escore de condição corporal (ECC). Os animais de primeira lactação apresentaram maior chance de sucesso ao primeiro serviço do que os animais multíparos. As vacas cobertas no período do inverno apresentaram, aproximadamente, cinco vezes mais chances de CPS do que as vacas cobertas no verão. Os animais que apresentaram doenças no periparto tiveram menor sucesso de concepção que os animais sadios. Os animais que apresentaram melhor condição ruminal, determinada pela RGP, principalmente durante o período de verão, tiveram melhor concepção do que os animais com RGP reduzida no verão. O ECC adequado nas diferentes fases produtivas das vacas (secagem, parto e cobertura) demonstrou ser uma importante ferramenta para identificar as vacas com risco de insucesso na concepção ao primeiro serviço. / These studies evaluate health and reproductive factors affecting dairy cows’ productivity. Through correlation studies were evaluated health occurrences and risk factors during peripartum for milk production at peak, after 305 days of lactation and conception failures on first service pos-partum (CFS). Using a commercial herd of “dairy holsteins cows” located in São Paulo state – Brazil, data were collect in 2001 and 2002. On the first study were used 15,613 observations, the statistical analyses data were processed on logistic regression and multiple regression analyses. The analyses showed that peripartum diseases and risk factors directly affected milk production, with different effects based on lactations times, requesting extra care on prophylactics to avoid diseases and improve milk production. On the second study were used 13,594 observations, the statistical analyses data were processed on logistic regression calculating chances ratio on risk factors isolation and risk factors association to success or failure on first service pos-partum. Results indicated as mainly risks factors: lactation times, year period that first service occurred, peripartum diseases, body score condition (BSC), milk protein and fat ratio (PFR). First lactation animals presented more chance of success to the first service than multiparous. Cows inseminated during winter time showed 5 times more chances of CFS than ones inseminated on summer time. Animals with peripartum diseases had less conception success than healthy ones. Cows with better rumminal condition (FPR) had a much better conception than ones with lower FPR. The correct BSC on different productive steps (dry-off, calving and breeding) showed to be an important tool to identify animals with higher risks of failure on first service conception.

Foram utilizadas 24 ovelhas da raça Santa Inês para coleta de tecido adiposo, sendo 16 lactantes e 8 secas. Oito ovelhas lactantes foram tratadas in vivo com bST (160 mg, em duas doses em intervalo de 14 dias) iniciando a injeção subcutânea de hormônio no 13 o dia de lactação, sendo que os animais restantes receberam somente vitamina E. Outros 8 animais encontravam-se em período seco, para que fosse verificada também a diferença das taxas lipolíticas em diferentes estados fisiológicos. Foi verificada a hipótese de que ocorra uma atuação da ST através de mudança na resposta do sistema antilipolítico da proteína Gi ligada a receptores da adenosina. O tratamento com ST exógena aumentou o ganho de peso das ovelhas lactantes (P<0,05) e também o peso dos cordeiros oriundos do grupo tratado ao final do período experimental, no entanto, não foi verificado aumento na produção de leite. As concentrações de AGNE diminuíram no decorrer da lactação para os dois grupos de ovelhas lactantes, chegando no 36 º dia de lactação a concentrações similares ao do grupo de ovelhas secas. A concentração de IGF-I sérico das ovelhas aumentou após tratamento com bST, sendo 8 dias após a segunda dose do hormônio (36 dias de lactação) superior à concentração observada para ovelhas secas. A lactação não teve influência na lipólise basal entre os diferentes estados fisiológicos. Houve um aumento significativo (P<0,01) da taxa lipolítica do tecido adiposo quando estimulada por b adrenérgico (ISO) para animais em quaisquer dos estados fisiológicos. Todavia, a taxa estimulada por ISO foi significativamente (P<0,01) mais elevada no tecido das ovelhas tratadas com bST. Na presença de ADA, ocorreu um aumento da taxa em relação à basal, mas não ultrapassou àquela estimulada por isoproterenol. O estímulo lipolítico pela eliminação de adenosina no meio através da ADA apresentou-se significativamente (P<0,01) mais elevado para ovelhas lactantes, sendo este efeito amenizado pelo tratamento com bST. O uso do análogo da adenosina PIA quando colocado no meio de cultura do tecido que foi tratado in vivo com bST teve seu efeito diminuído. Os resultados indicam um aumento da taxa lipolítica em resposta a agonista b-adrenérgico no tecido adiposo do omento de ovelhas lactantes tratadas com bST in vivo, bem como confirmam a hipótese de diminuição da ação inibitória da adenosina na cascata lipolítica naquele tecido. / Bovine somatotropin (bST) treatment in vivo alters adipose tissue metabolism by enhancing lipolytic response to adrenergic agonists. We examined the impact of bST and lactation on basal and stimulated lipolytic rates with isoproterenol (ISO; 10 -5 nM), adenosine deaminase (ADA; 0.75 U/mL), ISO plus ADA in short-term (2h) incubations of ovine adipose tissue. The anti-lipolytic effect of phenylisopropyladenosine (PIA; non-hydrolyzable adenosine analog) was evaluated at various concentrations (0.5, 1.5, 3, 100 nM). Sixteen lactating Santa Ines ewes were randomly assigned to two groups. They received two s.c. injections, with a 14 day interval, starting at d 13 postpartum with either bST (160 mg) or Vitamin E (control). Eight similar nonlactating ewes received vitamin E. Omental adipose tissue biopsies were taken on d 8 after the second bST or vitamin injection. The performance of weight and milk production were taken. The serum IGF-I was analyzed. The lipolytic rate was determined by NEFA release in serum and media as mEq of oleic acid.2h -1 g -1 tissue. Basal lipolytic rates did not change with lactation or with bST treatment in vivo (P>0,05). ISO stimulated lipolytic rate increased compared to basal and was higher for the adipose tissue from lactating ewes treated with bST (P<0,01).The lipolytic rate for adipose incubated with ADA was higher than basal for lactating ewes, with the greater response for the control. The ADA treated tissue from lactating ewes receiving bST showed intermediate lipolytic rates. Maximum lipolytic rate with ISO+ADA was also higher for lactating ewes treated with bST (P<0.01), and there was no difference between lactating and nonlactating ewes. The PIA effects were evaluated by the inhibition of ISO+ADA lipolysis, and adipose tissue from lactating ewes treated with bST showed a reduced response to PIA. The results demonstrate that in vivo somatotropin treatment increases maximal lipolytic rates stimulated by adrenergic agonist and decreases the antilipolytic effect of PIA in omental adipose tissue in ewes.

Os grandes avanços obtidos em quantidade de massa muscular nos animais domésticos foram alcançados por programas de melhoramento genético baseados na seleção de características fenotípicas observados na fase adulta do animal. No entanto, o número de precursores miogênicos e conseqüentemente, de fibras musculares, é determinado nos estádios embrionários do desenvolvimento. Este fato direcionou o programa miogênico como alvo de busca de potenciais transcritos candidatos que possam causar impacto sobre a deposição muscular em animais domésticos. Este trabalho objetivou identificar transcritos candidatos originais associados ao desenvolvimento e crescimento do tecido muscular esquelético em frangos (Gallus gallus). Um total de 4.534 transcritos (ESTs) identificados em trabalhos anteriores foram imobilizados em membrana de náilon (microarranjo) para permitir a investigação das diferenças no padrão de expressão entre genótipos e tecidos. O perfil transcricional do tecido muscular peitoral entre linhagens contrastantes para potencial de crescimento e deposição muscular da Embrapa Suíno Aves permitiu identificar 98 transcritos diferencialmente expressos, que foram validados por amplificação quantitativa de transcritos reversos (RT-PCRq), e localizados em regiões coincidentes às anteriormente mapeadas por QTLs. Estes transcritos são agora os candidatos preferenciais para a identificação de mutações e desenvolvimento de marcadores específicos que possam ser empregados em programas de melhoramento e seleção precoce ou indireta de aves. O mesmo microarranjo foi utilizado para caracterizar os transcritos desconhecidos pelo padrão de expressão entre cinco tecidos (cérebro, coração, fígado, músculo e pele). Esta abordagem permitiu identificar transcritos com padrão de expressão tecido-específico e tecido-preferencialmente expressos e caracterizar 24 transcritos desconhecidos como co-expressos aos transcritos músculo esquelético-específicos. Por fim, o orientador de axônio RGM-A (Repulsive guidance molecule A), identificado como músculo esquelético-específico, foi selecionado para ser funcionalmente analisado in vivo, para investigar uma possível função deste transcrito atípico no tecido muscular e comprovar a eficiência dos microarranjos em orientar a seleção de transcritos candidatos. O padrão de expressão de RGM-A em embriões de frango e os efeitos da super-expressão sobre Pax3 indicaram uma possível associação deste orientador de axônio com a formação da musculatura esquelética dos vertebrados superiores. Os transcritos candidatos indicados por análises de microarranjo deste trabalho serão úteis não apenas para que os programas de melhoramento sejam capazes de manter ou aumentar os índices de crescimento das aves, que atualmente buscam por informações adicionais para superar os limites impostos pelo próprio perfil genético alcançado em anos de seleção. Estes resultados também abriram novas perspectivas para a caracterização funcional in vivo de transcritos desconhecidos, tendo embriões de frango como modelo animal. / by animal breeding programs along the years based on the observation of adult phenotypic characters. But, the number of myogenic precursor cells and, consequently, the number of muscle fibers is determined during the embryonic stages of development. Therefore, the embryonic myogenic program is an ideal target for searching potential candidate-transcripts, that can influence skeletal muscle deposition in domestic animals. This work aimed to identify original candidate-transcripts associated with skeletal muscle development and growth in chicken embryos (Gallus gallus). A total of previously identified 4,534 transcripts (Expressed Sequence Tags) were transferred to a nylon membrane (microarray) to investigate differences in expression patterns among genotypes and tissues. The pectoral skeletal muscle transcriptional pattern between broiler and layer chicken lines allowed the identification of 98 differentially expressed transcripts, whose expression were validated by quantitative RT-PCR (Reverse-transcription Polymerase Chain Reaction), and were co-localized in coincident regions with previously mapped QTLs (Quantitative Trait Loci). These transcripts are now preferential candidates to further identify mutations, and/or to develop specific markers to be used in breeding programs for early or indirect selection of superior animals. The same microarray was used to characterize unknown transcripts by expression patterns among five tissues (brain, heart, liver, muscle and skin). This approach allowed to identify tissue-specific and/or preferentially-expressed transcripts, and to characterize 24 unknown transcripts as co-expressed with skeletal musclespecific ones. Finally, the axon guidance molecule RGM-A, identified as skeletal muscle-specific transcript by microarrays, was selected to be functionally analyzed in vivo, to investigate the function of this atypical transcript in the skeletal muscle and to demonstrate the approach efficiency to guide selection of candidate transcripts. The RGM-A expression pattern and the Pax3 phenotype after over-expression in chicken embryos indicated a possible association of this axon guidance with the skeletal muscle formation. The candidate transcripts identified by mycroarray analyses may be useful in animal breeding programs to increase the present gains in chicken growth rate, since additional information is urgently required to surpass current limits of selection gains. The results have also opened a new range of possibilities to promote the functional characterization in vivo of unknown transcripts, having chicken embryos as models.

O objetivo do presente estudo foi avaliar a aptidão reprodutiva de cães da raça Golden Retriever afetados pela distrofia muscular. Realizou-se avaliações andrológicas em 11 cães com idades entre 10 meses e 4 anos. Destes, 7 eram afetados pela distrofia muscular e 4 sadios, utilizados como controle. Todos foram submetidos a exame clinico, análise seminal e ultra-sonografia dos órgãos reprodutores. Analisou-se também a morfologia dos testículos e seus respectivos funículos espermáticos dos cães que foram a óbito. Detectou-se as seguintes alterações nos cães afetados pela distrofia: atrofia muscular, andar rígido, pneumonia por aspiração, fragilidade do diafragma com projeção do estomago para a cavidade torácica, megaesôfago e cardiomiopatia dilatada. Em relação aos órgãos genitais dois dos cães apresentaram criptorquidismo bilateral. Os resultados das análises seminais mostraram que os cães afetados pela distrofia possuem maior quantidade de defeitos espermáticos maiores e totais. Nas avaliações ultra-sonográficas não foram identificadas diferenças entre os cães afetados pela distrofia quando comparados com cães sadios. As análises histopatológicas evidenciaram alterações morfológicas nos testículos e músculos cremáster de cães afetados pela doença. Os testículos apresentaram degeneração testicular e o músculo cremáster retração de fibras musculares com hialinizacao dos miócitos. Conclui-se então que a distrofia muscular em cães da raça Golden Retriever pode comprometer sua aptidão reprodutiva. / The aim of the present research was to evaluate the reproductive condition of Golden Retriever dogs affected by muscular dystrophy. Breeding soundness examination was performed in 11 male dogs aged between 10 months and 4 years. Seven of this total were affected by muscular dystrophy and 4 healthy dogs that served as control. All dogs were submitted to a through physical exam, seminal evaluation and ultrasound of the reproductive tract. Testicle and spermatic cord morphology of post-mortem dogs were also examined. The following alterations were observed for the affected dogs: muscular atrophy, stiff walk, aspiration pneumonia, diaphragmatic fragility with stomach projection to the torax, megaesophagus e dilated cardiomyopathy. In relation to the genital tract, two dogs presented with bilateral cryptorchidism. Semen evaluation revealed high percentage of major and total sperm defects in affected dogs. Ultrasonographic exams were similar among healthy and affected dogs. Histophatology of the testicle and cremaster muscle revealed morphologic alterations in affected dogs represented by degeneration and muscular retraction with miocyte hyalinization, respectively. In conclusion, affected Golden Retriever dogs have their reproductive performance compromised by the muscular dystrophy.