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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

The Role of Orphanin FQ/Nociceptin in Prolactin Receptor Expression

Roberts, Kasey Marie 24 April 2010 (has links)
No description available.
32

Reproduction of domestic horses (Equus caballus): The effects of inbreeding, social environment and breeding management / Reproduction of domestic horses (Equus caballus): The effects of inbreeding, social environment and breeding management

DUBCOVÁ, Jana January 2015 (has links)
This thesis is focused on horse social behaviour and reproduction under human management. First part of the thesis covers issues about reproduction influenced by humans, breeding in restricted areas and artificial processes which can interfere or threaten the domestic horse population survival. These issues are described in lifetime order from conception, through lactation and maternal investment up to weaning, and on the background of detailed information about particular individuals. The second part is focused on social interactions and forming dominance hierarchy within the groups of domestic horses.
33

Reinício da atividade ovariana pós-parto de vacas Bos indicus em presença ou não do terneiro / Resumption of postpartum ovarian activity of Bos indicus cows in the presence or not of the calf

Xavier, Eduardo Gularte 29 May 2007 (has links)
Made available in DSpace on 2014-08-20T14:37:58Z (GMT). No. of bitstreams: 1 dissertacao_eduardo_xavier.pdf: 298275 bytes, checksum: 4cac97edc215b060c626ac29a1665c09 (MD5) Previous issue date: 2007-05-29 / The objective of this work was to test the effect of the presence or absence of the calf in the activities of estrous, follicular dynamics and hormone secretion of Bos indicus cows. Forty and six cows were divided in 3 groups. In group with contact (CC), the calves were prevented from suckling by being confined into a pen, that allowed auditory, olfactory and visual contact of the cows with their own calves (n=17). In group without contact (SC), the calves were weaned and prevented from any contact. In control group (T), the calves weren t weaned, remaining with their mothers (n=12). The CC group showed greater ratio of cows in estrous (76.5%) when compared to T (16.7%), but no difference from SC (64.7%). The CC group showed greater ratio of ovulation (76.5%) when compared to T (33.3%) and an apparent difference (p=0.06) when compared to SC (64.7%). The duration of estrous was lesser (p = 0.04) in group CC (8.4 h + 4.4 h) than the SC (12.9 + 13.4 h), however the group T (11 + 1.4 h) was not different from the others. The average interval between weaning and onset of estrus (35 + 6.3 h), weaning and end of estrus (44.4 + 5.4 h), intensity of estrus behavior (26.6 + 24 mounts), weaning and time of ovulation (70 + 12.7 h), onset of estrus and time of ovulation (33.3 + 9.3 h) and the end of estrus and time of ovulation (23.3 + 10.3 h) were not observed differences.The T group achieved 48 + 8.4 h of interval between weaning and the LH peak while in the weaned groups (CC and SC) the average interval was of 45.3 + 10.4 h, showing no differences between the CC group (42.5 + 8.2 h) and the SC (47.5 + 11.8 h). The interval between the peak of LH and the time of the ovulation presented a general average of 24.8 + 7.7 h, showing no differences between the groups T (25.5 + 5.7 h), CC (24.9 + 8 h) and SC (24.5 + 8.6 h). It was found that the contact between cow and calf during weaning was not different from that of the cows without any contact and there was no advantage in restricting contact between cow and calf. It was confirmed that weaning has a beneficial effect on the percentage of estrous and ovulation when compared to cows not weaned. / O objetivo deste trabalho foi estudar o efeito da presença ou ausência do terneiro nas atividades de estro, dinâmica folicular e níveis hormonais em vacas de origem Bos indicus. Quarenta e seis vacas foram divididas em 3 grupos. No grupo com contato (CC), os terneiros foram desmamados e impedidos de mamar, mas mantidos em um curral, o qual permitia contato auditivo, olfativo e visual das vacas com sua cria (n=17). No grupo sem contato (SC), os terneiros foram desmamados e impedidos de qualquer contato (n= 17). No grupo T (n=12), as crias não foram desmamadas, permanecendo juntas às suas mães, constituindo o grupo testemunha. O grupo CC (76,5%) apresentou maior proporção de vacas em estro quando comparado ao T (16,7%), mas não diferente do SC (64,7%). O grupo CC possui maior porcentagem de vacas ovuladas (76,5%) quando comparado ao T (33,3%) e uma diferença aparente (p=0,06) quando comparado ao SC (64,7%). A duração do estro foi menor (p = 0,04) no grupo CC (8,4 h + 4,4 h) quando comparado ao SC (12,9 + 13,4 h). O intervalo entre o desmame e o início do estro (35 + 6,3 h), o desmame e o final do estro (44,4 + 5,4 h), a intensidade do estro (26,6 + 24 montas), o desmame e a ovulação (70 + 12,7 h), o início do estro e a ovulação (33,3 + 9,3 h) e o final do estro e a ovulação (23,3 + 10,3 h) não foram diferentes entre os tratamentos. As vacas do grupo T obtiveram 48 + 8,4 h de intervalo entre o desmame e o pico de LH enquanto que nos grupos desmamados (CC e SC) o intervalo médio foi de 45,3 + 10,4 h, não havendo diferença entre as vacas do grupo CC (42,5 + 8,2 h) e SC (47,5 + 11,8 h). O intervalo entre o pico de LH e o momento da ovulação apresentou uma média geral de 24,8 + 7,7 h, não havendo diferença entre os grupos T (25,5 + 5,7 h), CC (24,9 + 8 h) e SC (24,5 + 8,6 h). Verificou-se que o contato da vaca com a cria durante o desmame não foi diferente das vacas sem contato algum e não houve vantagem em restringir o contato da mãe com sua cria. Ficou confirmado que o desmame exerce um efeito benéfico na porcentagem de estro e ovulação quando comparado a vacas não desmamadas.
34

Beifütterung von Ferkelmilch in der Abferkelbucht: Einflüsse auf die Leistung und Gesundheit von Sauen und ihren Ferkeln

Pustal, Anna Josefine 17 June 2014 (has links)
Das Ziel der vorliegenden Studie war die Untersuchung der Effekte einer automatischen ad libitum Beifütterung von Milchaustauscher zusätzlich zur Sauenmilch in der Abferkelbucht auf den Gewichtszuwachs, die Verlustrate und die Notwendigkeit medikamentöser Behandlungen der Saugferkel. Zudem wurde der Einfluss der Ersatzmilch auf die Körperkondition der Sauen analysiert. Desweiteren wurde untersucht, ob ein Einfluss auf medikamentöse Behandlungen der Sauen, die Gesäugegesundheit und das Bakterienspektrum der Sauenmilch gegeben ist. Außerdem sollten Aussagen zum hygienischen Status des Milchtassensystems und der angeschlossenen Rohrleitungen und Behälter getroffen werden.
35

Does Location Matter? Investigating the Impact of Environmental Enrichment Location on the Welfare, Behavior, and Performance of Sows and Piglets in Farrowing Crates

Katherine E Klassen (19201075), Jessica A. Pempek (14103828), Marisa A. Erasmus (7480759), Brian Richert (19201091), Kara Stewart (5236979), Kristina M. Horback (12152890) 24 July 2024 (has links)
<p dir="ltr">To meet the growing demands for pork products, lactating sows are often housed in farrowing crates to reduce piglet crushing. However, the public has raised welfare concerns about farrowing crate systems due to the confinement and barren environment, which can impair social interactions between sow and piglets, change their activity levels, and alter how sows and piglets satisfy their motivated behaviors to chew and explore by oral manipulation of pen and pen mates. Barren and confined environments can result in skin abrasions caused by oral manipulations and fighting, physiological stress, inactivity, and abnormal behaviors, which can have an impact on sows’ and piglets’ welfare, productivity, and behavior. Previous work on environmental enrichments has shown promise to improve average daily gain, activity levels, stress, and behavioral repertoire. However, the majority of studies on pig environmental enrichments take place after weaning and research investigating the impact enrichments have during lactation is limited. In addition, research on maximizing the use of environmental enrichments based on the location inside the farrowing crate systems has not been conducted. To address the knowledge gaps concerning the impact of the location of environmental enrichments on the welfare, behavior, and productivity of sows and piglets in farrowing crate systems and to provide educational material on pig enrichment, this dissertation consists of two parts: Chapters 2 and 3 examine the effects of the location of environmental enrichments in farrowing crate systems on sows’ and piglet’s welfare, productivity, and behavior. Chapter 5 is an extension article on the different types of environmental enrichments and the best strategies for implementing enrichment in swine operations.</p><p dir="ltr">In Chapter 2, sows (n = 37) and focal piglets (n = 148) were assigned to three treatment groups: SPE (both sows and piglets had access to enrichment objects), PE (only piglets had access to enrichment objects), and CON (control group with no enrichment) blocked by sow parity and genetics. Sow posture and piglet behavior during the lactation and nursery phases were observed at various times after birth and weaning. Environmental enrichments significantly influenced the behaviors of suckling piglets, reducing pig-directed and agonistic behaviors. Piglets with enrichments tended to explore the pen less and engage in more social behaviors. The location of enrichments also impacted behaviors, with higher nursing behavior observed during mid-lactation for piglets with access to enrichments (PE) and increased interaction with enrichments when they were accessible to both sows and piglets (SPE). Treatment did not affect sow postural changes or most nursery behaviors, except for walking, which increased in SPE nursery piglets compared to CON piglets. Overall, the study demonstrated positive effects of environmental enrichments on suckling piglets in farrowing crate systems, highlighting the importance of enrichment placement on nursing behaviors and enrichment interaction.</p><p dir="ltr">In Chapter 3, the same sows and piglets were used to investigate the effects of enrichment location on the welfare (skin lesions, pressure sores, salivary cortisol, and tear stains) and performance (average daily gain and piglet crushing) of the sows and piglets. This study used the same animals that were assigned the treatment group, housing, and management practices from Chapter 2. Salivary cortisol samples were collected from sows at four time points: 24 hours after moving into farrowing crates, 24 hours after treatment group assignment, midway between moving into crates and weaning, and on the day of weaning. Pressure sores of sows were scored on days 1, 4, 7, 10, 14, and 17 after farrowing. For suckling piglets, tear stains and skin lesions were assessed on the same days, and their average daily gain (ADG) was analyzed weekly during lactation. In the nursery phase, salivary cortisol was collected from piglets on the day of weaning and days 1, 7, and 14 post-weaning, with tear stains and skin lesions measured on those days as well. Nursery ADG was analyzed from weaning to day 14 post-weaning. Results indicated that control (CON) sows were less likely to have no pressure sores compared to sows with shared (SPE) enrichments, while piglets in the enriched treatment groups (PE and SPE) had smaller tear stain areas than those in the CON group. Treatment influenced skin lesions in suckling piglets, with enriched piglets having fewer lesions in the ear and front body regions. There was no treatment effect on salivary cortisol for both sows and nursery piglets, nor did treatment affect ADG, piglet crushing, or nursery skin lesions. The provision of environmental enrichments in farrowing crates reduced pressure sores of sows, skin lesions of suckling piglets and tear stains of suckling and nursery piglets.</p><p dir="ltr">Overall, providing environmental enrichments to suckling piglets reduced aggression, as evidenced by fewer agonistic and pig-directed behaviors, and resulted in fewer skin lesions compared to piglets without enrichments. This suggests potentially reduced stress levels in enriched piglets, indicated by smaller tear stain areas. While most behaviors and skin lesion scores showed no significant differences during the nursery phase, enriched piglets continued to have smaller tear stains. Enrichment location influenced the following: sows had fewer pressure sores, and suckling piglets interacted more with enrichments and exhibited fewer pig-directed behaviors when enrichments were accessible to both sows and piglets compared to the only piglet enriched treatment group. Piglets with access only to enrichments also performed more nursing behaviors during mid-lactation compared to the control group. Overall, the study highlights the benefits of environmental enrichments in farrowing crate systems, particularly the positive impact of enrichment location on the welfare and behavior of sows and piglets.</p><p dir="ltr">Lastly, in Chapter 5, the extension article discusses the definition of environmental enrichment and its impact on pigs’ welfare. The article also delves into the five types of environmental enrichments (nutritional, occupational, physical, sensory, and social), providing examples of each. Additionally, the article offers five practical tips for efficiently and successfully implementing environmental enrichments in swine herds.</p>
36

Myofunkční porucha u dětí / Myofunctional disorder in children

Říha, Ivo January 2015 (has links)
Thesis "Myofunctional disorder of children" is about myofunctional disorder with a focus on logopedics and issues of human speech. The whole work has, however, significantly multidisciplinary character. The theoretical part of the thesis is focused on orofacial complex, swallowing and speech complex in all its breadth. It is also focused on nutrition problems at an early age and on related activities. Readers can also find information about orthodontic anomalies that are directly related to myofunctional disorder. A large area is dedicated to myofunctional disorder itself - terminology, etiology, symptomatology, diagnosis, prevention and therapy. As an important section of practical part of the work serves a research on a sample of 15 children diagnosed with myofunctional disorder. The sample was subjected to qualitative analysis, where an outcome demonstrates 3 case studies demonstrating the degree of seriousness of 3 myofunctional disorders. Additionally, there is also simple quantitative analysis and its outcome is an overview chart. KEYWORDS Myofunctional disorder, orofacial, tongue, ortodontic anomalies, breast- feeding, suckling, mastification, swallowing, speech - articulation.
37

Untersuchungen zur Reproduktion und Kälberentwicklung in ökologisch bewirtschafteten Mutterkuhherden

Gutbier, Stefan 26 June 2003 (has links)
Untersucht wurden an 901 Mutterkühen der Einfluss der Länge des Zeitintervalls zwischen der Kalbung und der Zustellung des Zuchtbullen auf die Fruchtbarkeitsleistungen der Mutterkühe sowie die Fruchtbarkeit von Mutterkühen mit im Jahresverlauf unterschiedlichen Kalbe- und Belegungszeiträumen. Mit dem Einschränken des Intervalls zwischen der Kalbung und der Zustellung des Zuchtbullen unter 22 Tage wird die maximale Zahl Kalbungen pro Kuh und Jahr ermöglicht. Gleichzeitig verschiebt sich die Kalbeperiode im Jahresverlauf und die Kalbezeit wird verlängert. Die Verlängerung dieses Zeitintervalls bewirkt eine konzentriertere Kalbeperiode, aber auch weniger Kalbungen pro Kuh und Jahr. Für durchschnittlich eine Kalbung pro Kuh und Jahr und gleichzeitig eine gedrängte und im Jahresverlauf konstante Kalbeperiode ist die Zustellung des Deckbullen 40 bis 50 Tage nach der Kalbung zu empfehlen. In der Zeit unmittelbar vor Ende des Winters sowie während und kurz nach dem Weideaustrieb konzipieren durch die schlechte Körperkondition der Kühe nur wenige Tiere. Deshalb sollten, um eine Verlängerung der Kalbeperiode zu vermeiden, in diesem Zeitabschnitt Mutterkühe nicht belegt werden. Defizite der Trächtigkeitsrate können in kurzer Zeit kompensiert werden und sind deshalb für die Wahl der geeigneten Kalbeperiode von geringer Bedeutung. Die Daten von je 30 Kälbern mit und ohne Konzentratzufütterung erbrachten Erkenntnisse zur Kraftfutteraufnahme von Mutterkuhkälbern aus der Winterkalbung während der Stallhaltungsperiode und dessen Einfluss auf die Körpermasseentwicklung der Kälber. Vor dem 40. Lebenstag nehmen nur sehr wenige Mutterkuhkälber aus der Winterkalbung Kraftfutter auf. Ab 70 Tagen Lebensalter bringt die Zufütterung von Konzentraten bis zum Weideaustrieb Vorteile bei der Körpermasseentwicklung gegenüber Kälbern ohne Konzentratzufütterung. Nach der Einstellung der Konzentratfütterung mit Weideaustrieb haben zugefütterte Kälber erhebliche Umstellungsprobleme. Die Kälber ohne Konzentrataufnahme gleichen während der Weideperiode die Körpermassedefizite aus der Stallhaltung durch kompensatorisches Wachstum annähernd aus. Die Konzentratfütterung an Kälber aus der Winterkalbung während der Stallhaltungsperiode beeinflusst, wenn sie während der nachfolgenden Weidehaltung nicht fortgesetzt werden soll, das wirtschaftliche Ergebnis der Mutterkuhhaltung negativ. 40 Mutterkuhkälber aus der Sommerkalbung wurden nach Weideabtrieb im Stall mit Kraftfutter zugefüttert und tierindividuell der Einfluss der aufgenommenen Kraftfuttermenge auf die Körpermasseentwicklung der Kälber ermittelt. Der Beginn der Kraftfutteraufnahme, die täglichen Verzehrsmengen und die gesamt aufgenommene Menge sind zwischen älteren Mutterkuhkälbern auf Grund unterschiedlicher Milchmengen der Mutterkühe sowie individueller Vorlieben der Tiere stark differenziert. Da Kälber mit hoher Konzentrataufnahme weniger Grundfutter aufnehmen und Luxuskonsum betreiben, ist die Limitierung der Verzehrsmengen zu empfehlen. Mittels Konzentratzufütterung an ältere Mutterkuhkälber können Defizite der Lebendmasseentwicklung durch kompensatorisches Wachstum ausgeglichen und damit bei den über die Mütter schlechter versorgten Kälbern Qualitätsverbesserungen erreicht werden. Entscheidend für die Effektivität der Konzentratzufütterung ist die Höhe der Kraftfutteraufnahme, da einerseits die Kosten der Futterbereitstellung mit steigendem Verbrauch sinken und andererseits mit erhöhter Verzehrsmenge der Kraftfutteraufwand je kg Körpermassezuwachs zunimmt. / The objective of this study is to show the influence of the length of the timeinterval between the calving and the taking an A.I.bull and its impact on the fertility of suckler cows as well as the fertility of suckler cows with different period of mating within a year. This study includes 901 suckler cows. With reducing the interval between calving and take an A.I.bull below 22 days the maximun number of calvings pro cow is reached. In parallel the period of calving will be delayed and the period of calving will increase. The increase of this timeinterval will lead into a more concentrated period of calving, but less calvings per cow and year. To get an average of one calving per year and cow and at the same time get a reduced and constant period of calving it is advisable to taking an A.I.bull 40 to 50 days after the calving. Within the time right before the end of the winter and right after the put out to pasture not to many cows conceive due to their bad physical conditions. Therefore, to prevent an increase of the period of calving it is advisable not to insemination of suckler cows in these timeperiods. Deficits within the rate of pregnant can be compensated in a short period of time and are therefore of less importens when choosing the suitable period of calving. Data of each 30 calfes with and without feed concentrates showed the impact the feeding concentrates of calfs of suckler cows from the calving in the wintertime during the Stallhaltungsperiode has and its influence on the development of body mass of calfes. Before the 40 day only a few calfs of suckler cows feeding concentrates. From the 70 day on the feeding of concentrates untill the put out to pasture will bring advanatges in the development of body mass. After the cessation of feeding concentrates during ranching calfes have considerable adaption problems. The calfes without feeding concentrates are capable of compensating the body mass deficiency during the period of ranching gained during the housing. The feed concentrates while the housing to calfes from the calving in the wintertime will influence the economic result of the single suckling negative if the feeding is not continuite during the ranching. 40 calfs of suckler cows originated from the calving in the sommertime have been feed with concentrates after the take back from pasture and the influence of the quantity of concentrates on the development of body mass has been gathered for each individual. The start of the feeding concentrates, the daily quantity of feed and the amount of milk differ a lot between the calfs of suckler cows because different amounts of milk provided by the suckler cows as well as the individual preference of the animals. It is advisable to limit the amount of quantity of feed because calfes with feed concentrates "eat" less basic feed and therefore luxury feeding. By concentrate feeding it is possible to compensate defizite within the development of body mass and with that have a quality improvement atwith. The most important point to have a effectiv feed concentrates is the amount of the feeding concentrates, because the costs of the delivery of feed decrease with increasing consumption and on the other hand the costs of concentrates per kg increases with increased feed.
38

Efeitos do cloreto de mercúrio e do cloreto de zinco sobre parâmetros renais e hepáticos em ratas lactantes e não-lactantes / Effects of mercury chloride and zinc chloride on renal and hepatic parameters in lactating and non-lactating rats

Favero, Alexandre Marafon 08 April 2011 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / The aim of this study was to compare the effects of mercuric chloride (HgCl2) on renal and hepatic parameters in adult non-lactating and lactating rats and their pups and to assess the potential preventive role of Zn, given as zinc chloride (ZnCl2), on the nephrotoxic and hepatotoxic effects caused by exposure to inorganic mercury. Nonlactating and lactating rats were pre-exposed to a daily dose of ZnCl2 (27 mg/kg/day; s.c.) or saline 0.9% during five consecutive days and to a daily dose of HgCl2 (5 mg/kg/day; s.c.) or saline 0.9% for the five subsequent days. The exposure of lactating rats to metals began on day 3 of lactation. Suckling pups were exposed to metals exclusively through maternal milk. Animals were observed daily throughout the study for signs of toxicity and mortality. Water and food consumption of lactating and nonlactating rats were monitored daily during the entire period of exposure to metals. Animals were euthanized 24 h after the last dose of HgCl2 and tissue samples were collected (blood, kidney and liver) to analyze the following parameters: daminolevulinic acid dehydratase (d-ALA-D) activity; biochemical parameters indicative of renal (plasma urea and creatinine levels) and hepatic (plasma AST, ALT and LDH activities) toxicity and the metal levels (Hg and Zn) in all tissues studied. In nonlactating rats, the survival rate; food consumption; body and kidney weights; blood and renal d-ALA-D activity; plasma urea and creatinine levels; plasma ALT and AST activities; renal histology; blood Zn levels and blood, kidney and liver Hg levels were significantly affected by HgCl2 exposure. Previous exposure to ZnCl2 prevented some of the effects of mercury, such as: decrease in survival rate, increase in plasma urea and creatinine levels, inhibition in blood (partially) and renal d-ALA-D activity, the increase in plasma AST (partially) activity and the decrement in blood Zn levels. In contrast, ZnCl2 was unable to prevent the effects of mercury on the decrease in food consumption and in body and kidney weights, inhibition of plasma ALT activity, renal histological alterations and on the increased Hg levels in tissues. In lactating rats, food consumption, body and kidney weights, blood and hepatic d-ALA-D activity, plasma ALT activity and Hg levels in blood and kidneys were significantly modified by HgCl2 exposure. Previous exposure to ZnCl2 was not able to prevent any physiological and biochemical changes induced by HgCl2 exposure. Moreover, the pre-exposure to ZnCl2 potentiated the effects of HgCl2 exposure on retention of Hg in renal and hepatic tissues and induced histological alterations in the liver (which were not observed when lactating rats were exposed to HgCl2 alone). In pups, body weight gain, absolute kidney and liver weights and retention of Hg in these tissues were significantly altered by indirect exposure to heavy metal through maternal milk. None of these changes were prevented by pre-exposure of their mothers to ZnCl2. Taken together, this study showed for the first time that lactating rats exposed to HgCl2 presented distinct biochemical responses comparing to non-lactating rats when renal and hepatic parameters were evaluated. Furthermore, these results showed that mercury is transferred to the pups through maternal milk and that mercury levels available to pups were not sufficient to induce any change in biochemical parameters evaluated. The preventive effect of ZnCl2 on renal toxicity induced by HgCl2 in non-lactating rats suggests effectively that it serves as a promising alternative for the preventive treatment of inorganic mercury poisoning cases; however, since pre-exposure to ZnCl2 potentiated the effects of HgCl2 on mercury levels in kidney and liver and induced histological changes in hepatic tissue of lactating rats, we suggest that ZnCl2 should be used with caution during lactation and that more studies are necessary to ensure the safety of its use in this period. / O objetivo deste estudo foi comparar os efeitos da exposição ao cloreto de mercúrio (HgCl2) sobre parâmetros renais e hepáticos em ratas adultas não-lactantes e ratas lactantes e seus filhotes, e avaliar o possível efeito preventivo do zinco (Zn), administrado na forma de cloreto de zinco (ZnCl2), sobre os efeitos nefro e hepatotóxicos causados pela exposição ao mercúrio inorgânico. As ratas lactantes e nãolactantes foram pré-expostas a uma dose diária de ZnCl2 (27 mg/kg/dia; s.c.) ou solução salina 0,9% durante cinco dias. Nos cinco dias subsequentes, as ratas foram expostas a uma dose diária de HgCl2 (5 mg/kg/dia; s.c.) ou salina 0,9%. A exposição das ratas lactantes aos metais iniciou-se no 3º dia de lactação. Os filhotes foram expostos aos metais exclusivamente via leite materno. Os animais foram observados diariamente quanto aos sinais de toxicidade e mortalidade. O consumo de água e de ração das ratas lactantes e não-lactantes foi monitorado diariamente durante o período de exposição aos metais. Os animais foram eutanaziados 24 horas após a administração da última dose de HgCl2. Amostras de sangue, rim e fígado foram retiradas para a análise dos seguintes parâmetros: atividade da enzima d-aminolevulinato desidratase (d-ALA-D); parâmetros bioquímicos indicativos de toxicidade renal (níveis plasmáticos de uréia e creatinina) e hepática (atividade das enzimas AST, ALT e LDH plasmáticas) e os níveis de metais (Hg e Zn) nos tecidos estudados. Nas ratas não-lactantes, a taxa de sobrevivência, o consumo de ração, os pesos do corpo e dos rins, a atividade da enzima d-ALA-D sanguínea e renal, os níveis plasmáticos de uréia e creatinina, a atividade das enzimas AST e ALT plasmáticas, a histologia do tecido renal, os níveis de zinco no sangue e os níveis de mercúrio no sangue, rins e fígado foram significativamente alterados pela exposição ao HgCl2. A exposição prévia ao ZnCl2 preveniu alguns dos efeitos induzidos pelo mercúrio, tais como: a diminuição na taxa de sobrevivência, o aumento nos níveis plasmáticos de uréia e creatinina, a inibição da atividade da enzima d-ALA-D sanguínea (parcialmente) e renal, o aumento na atividade da AST (parcialmente) e a diminuição dos níveis sanguíneos de zinco. Por outro lado, o ZnCl2 não foi capaz de prevenir os efeitos do mercúrio sobre a diminuição do consumo de ração e dos pesos corporal e renal, a inibição da atividade da ALT, as alterações histológicas e os níveis de mercúrio nos tecidos. Nas lactantes, o consumo de ração, os pesos do corpo e dos rins, a atividade das enzimas d-ALA-D sanguínea e hepática e ALT plasmática, os níveis de zinco no sangue e os níveis de mercúrio no sangue e nos rins foram significativamente alterados pela exposição ao HgCl2. A pré-exposição ao ZnCl2 não preveniu nenhuma das alterações bioquímicas e fisiológicas induzidas pela exposição ao HgCl2. Além disso, essa pré-exposição potencializou o acúmulo de mercúrio nos tecidos renal e hepático e induziu o aparecimento de alterações histológicas no fígado, as quais não foram observadas nas ratas lactantes expostas exclusivamente ao HgCl2. Em relação aos filhotes, o ganho de peso corporal, os pesos absolutos de rins e fígado e o acúmulo de mercúrio nesses tecidos foram significativamente alterados pela exposição indireta ao metal tóxico via leite materno. Nenhuma dessas alterações foram prevenidas pela exposição prévia das lactantes ao ZnCl2. Este estudo demonstrou, pela primeira vez, que as ratas lactantes expostas ao HgCl2 apresentam respostas bioquímicas distintas em relação as ratas adultas não-lactantes quando analisados parâmetros renais e hepáticos de toxicidade. Além disso, estes resultados demonstram que o mercúrio é transferido aos filhotes via leite materno e que os níveis de mercúrio disponíveis não são suficientes para alterar os parâmetros bioquímicos analisados. O papel preventivo do ZnCl2 sobre a toxicidade renal induzida pelo HgCl2 nas ratas não-lactantes sugere efetivamente que ele serve como alternativa promissora no tratamento preventivo dos casos de exposição ao mercúrio inorgânico. Entretanto, uma vez que a pré-exposição ao ZnCl2 potencializou os efeitos do HgCl2 sobre os níveis de mercúrio em rim e fígado e induziu alterações histológicas no tecido hepático de ratas lactantes, sugere-se que o ZnCl2 deva ser usado com cautela durante o período da lactação e que mais estudos são necessários para certificar-se da segurança de seu uso nesse período.
39

Avaliação da vacina anti-rábica inativada, produzida em cérebros de camundongos lactentes, na imunização de macacos-prego (Cebus Apella, LINNAEUS, 1758) mantidos em cativeiro / Evaluation of inactivated suckling mouse brain rabies vaccine for immunization of capuchin monkeys (Cebus apella, Linnaeus, 1758) held confined

Passos, Estevão de Camargo 13 October 1998 (has links)
Foram imunizados 27 macacos-prego (Cebus apella), por via intramuscular, com vacina anti-rábica inativada, produzida a partir de cérebros de camundongos lactentes (VARCCL), empregada nas campanhas de prevenção da raiva animal de cães e gatos. Os animais permaneceram em cativeiro, durante o período de junho de 1995 a junho de 1997, sendo divididos em 3 grupos experimentais e vacinados conforme o esquema: grupo I, com 3 doses a intervalo de 30 dias; o II, com 2 doses a intervalo 30 dias e reforço aos 210 dias; e, o III com uma dose e reforço aos 210 dias. A revacinação anual foi realizada em todos os animais aos 365 dias. As amostras de soros foram obtidas aos 0, 30, 60, 90, 150, 210, 240, 300, 365, 395, 545 e 730 dias, e armazenadas à temperatura de -20ºC, e a dosagem dos anticorpos realizada através do teste simplificado da inibição da fluorescência. Verificou-se que os animais do grupo I apresentaram soroconversão mais duradoura (12232 dias) do que os dos grupos II e III (p<0,05) após a vacinação inicial, e os animais do grupo I apresentaram soroconversão mais duradoura (183,6120,6 dias) do que os dos grupos II (p<0,05), após a revacinação anual aos 365 dias. A VARCCL induziu a resposta imune nos macacos-prego, após vacinação e revacinação, respectivamente, em 81,4 por cento e 76,0 por cento dos animais; com produção de anticorpos neutralizantes, iguais ou superiores a 0,5 UI/ml, porém, de curta duração; não constituindo assim, imunógeno apropriado para ser utilizado na rotina de imunização destes animais de difícil lide, mantidos em cativeiro / Twenty-seven capuchin monkeys (Cebus apella) were intramuscularly immunized with inactivated suckling mouse brain rabies vaccine (SMBV) employed in campaigns for animal rabies prevention in dogs and cats. The animals were kept confined from June, 1995 to June, 1997. They were divided into 3 experimental groups and vaccinated according to the following scheme: group I, with 3 doses within a 30-day interval; group II, with 2 doses within a 30-day interval and a booster dose at the 210th day; and, group III; with a single dose and a booster dose at the 210th day. All animals were given the annual re-vaccination at the 365th day. Sera samples were obtained at the 0th, 30 th, 60th, 90 th, 150 th, 210 th, 240 th, 300 th, 365 th, 395 th, 545 th e 730 th days and kept stored at 20ºC. The antibodies dosage was carried out through the simplified inhibition fluorescent test. The following results were observed: animals belonging to group I had longer humoral immune response (12232 days) than the ones belonging either to group II or group III (p<0.05) after initial vaccination; animals of group I presented longer humoral immune response (183.6120.6 days) than the ones of the group II (p<0.05) after the annual re-vaccination at the 365th day. The SMBV induced humoral immune response in capuchin monkeys after vaccination and re-vaccination in respectively 81.4 per cent and 76.0 per cent of the animals, producing neutralizing antibodies equal to or higher than 0.5 IU/ml; however, they were short-lasting, being therefore not appropriate as an immunogen to be used routinely in the immunization of these animals which are difficult both to be deal with and to be held confined
40

Avaliação da vacina anti-rábica inativada, produzida em cérebros de camundongos lactentes, na imunização de macacos-prego (Cebus Apella, LINNAEUS, 1758) mantidos em cativeiro / Evaluation of inactivated suckling mouse brain rabies vaccine for immunization of capuchin monkeys (Cebus apella, Linnaeus, 1758) held confined

Estevão de Camargo Passos 13 October 1998 (has links)
Foram imunizados 27 macacos-prego (Cebus apella), por via intramuscular, com vacina anti-rábica inativada, produzida a partir de cérebros de camundongos lactentes (VARCCL), empregada nas campanhas de prevenção da raiva animal de cães e gatos. Os animais permaneceram em cativeiro, durante o período de junho de 1995 a junho de 1997, sendo divididos em 3 grupos experimentais e vacinados conforme o esquema: grupo I, com 3 doses a intervalo de 30 dias; o II, com 2 doses a intervalo 30 dias e reforço aos 210 dias; e, o III com uma dose e reforço aos 210 dias. A revacinação anual foi realizada em todos os animais aos 365 dias. As amostras de soros foram obtidas aos 0, 30, 60, 90, 150, 210, 240, 300, 365, 395, 545 e 730 dias, e armazenadas à temperatura de -20ºC, e a dosagem dos anticorpos realizada através do teste simplificado da inibição da fluorescência. Verificou-se que os animais do grupo I apresentaram soroconversão mais duradoura (12232 dias) do que os dos grupos II e III (p<0,05) após a vacinação inicial, e os animais do grupo I apresentaram soroconversão mais duradoura (183,6120,6 dias) do que os dos grupos II (p<0,05), após a revacinação anual aos 365 dias. A VARCCL induziu a resposta imune nos macacos-prego, após vacinação e revacinação, respectivamente, em 81,4 por cento e 76,0 por cento dos animais; com produção de anticorpos neutralizantes, iguais ou superiores a 0,5 UI/ml, porém, de curta duração; não constituindo assim, imunógeno apropriado para ser utilizado na rotina de imunização destes animais de difícil lide, mantidos em cativeiro / Twenty-seven capuchin monkeys (Cebus apella) were intramuscularly immunized with inactivated suckling mouse brain rabies vaccine (SMBV) employed in campaigns for animal rabies prevention in dogs and cats. The animals were kept confined from June, 1995 to June, 1997. They were divided into 3 experimental groups and vaccinated according to the following scheme: group I, with 3 doses within a 30-day interval; group II, with 2 doses within a 30-day interval and a booster dose at the 210th day; and, group III; with a single dose and a booster dose at the 210th day. All animals were given the annual re-vaccination at the 365th day. Sera samples were obtained at the 0th, 30 th, 60th, 90 th, 150 th, 210 th, 240 th, 300 th, 365 th, 395 th, 545 th e 730 th days and kept stored at 20ºC. The antibodies dosage was carried out through the simplified inhibition fluorescent test. The following results were observed: animals belonging to group I had longer humoral immune response (12232 days) than the ones belonging either to group II or group III (p<0.05) after initial vaccination; animals of group I presented longer humoral immune response (183.6120.6 days) than the ones of the group II (p<0.05) after the annual re-vaccination at the 365th day. The SMBV induced humoral immune response in capuchin monkeys after vaccination and re-vaccination in respectively 81.4 per cent and 76.0 per cent of the animals, producing neutralizing antibodies equal to or higher than 0.5 IU/ml; however, they were short-lasting, being therefore not appropriate as an immunogen to be used routinely in the immunization of these animals which are difficult both to be deal with and to be held confined

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