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1.
Ci. Rural ; 46(8): 1460-1465, ago. 2016. tab
Artigo em Inglês | VETINDEX | ID: vti-22511

Resumo

The study aimed to evaluate the effects of arginine supplementation in the lactation diet of sows on their milk composition, litter performance and piglet survival. Sixty-four lactating Landrace x Large White sows, parity 1 to 7, were randomly assigned to two treatments: 1) Control - a corn/soybean meal based diet with 1.10% standardized ileal digestible (SID) lysine and 3,475kcal of metabolizable energy (ME) kg-1, and 2) arginine - the control diet top-dressed daily with arginine at 1% of feed allowance. The daily feed allowance per sow was 5.0 and 7.5kg from day (D)0 to D7 and D8 to D21, respectively. The average litter size was 12.8 piglets after cross-fostering. Litters were weighed on D1, D10, and D21 of lactation and pre-weaning mortality was recorded. Samples of milk (60mL) were collected from all functional teats at D10 and D20 of lactation. There were no effects (P>0.05) of arginine supplementation on piglet weight, litter weight, and average daily gain of piglets at D10 and D21 of lactation. The interaction between weight day and treatment was not significant (P>0.05) for any of these response variables. The percentages of piglets that survived until D10 and D21 were 90.3% and 88.3%, respectively, with no difference (P>0.05) between treatments. There were no effects (P>0.05) of the lactation day (D10 or D20), treatment or the interaction between them on crude protein and amino acid content in milk. Top-dressing arginine at 1% of feed allowance of the lactation diet of sows does not affect litter performance and survival and does not influence the amino acid content or arginine: lysine ratio of milk.(AU)


O estudo teve o objetivo de avaliar o efeito da suplementação de arginina na dieta de lactação de porcas sobre a composição do leite, desempenho da leitegada e sobrevivência dos leitões. Foram utilizadas 64 porcas lactantes Landrace - Large White, com parição de 1 a 7, aleatoriamente distribuídas em dois tratamentos: 1) Controle - dieta a base de milho e soja com 1,10% de lisina digestível e 3.475kcal de energia metabolizável; e 2) Arginina - dieta controle suplementada com arginina via top-dress em nível de 1% sobre a dieta fornecida. Diariamente, as matrizes receberam 5,0 e 7,5kg do D0 ao D7 e D8 ao D21, respectivamente. Após a uniformização das leitegadas, o número médio de lactentes foi de 12,8 leitões. As leitegadas foram pesadas no D1, D10 e D21 da lactação e a mortalidade pré-desmame foi registrada. Foram coletadas amostras de leite (60mL) de todas as tetas funcionais de cada porca no D10 e no D20 da lactação. Não houve efeito (P>0,05) da suplementação de arginina sobre o peso dos leitões, peso da leitegada e ganho de peso médio diário dos leitões no D10 e D21 da lactação. A interação entre dia da pesagem e tratamento não foi significativa (P>0,05) para as variáveis-resposta analisadas. Os percentuais de leitões vivos até o D10 e D21 foram de 90,3% e 88,3%, respectivamente, sem diferença (P>0,05) entre os tratamentos. Não houve efeito (P>0,05) do dia de lactação (D10 ou D20), tratamento ou interação entre eles na proteína bruta e conteúdo de aminoácidos do leite. A suplementação de arginina em nível de 1% da dieta fornecida diariamente não teve efeito sobre o desempenho e sobrevivência da leitegada e não influenciou no conteúdo de aminoácidos ou na relação arginina:lisina do leite.(AU)


Assuntos
Animais , Feminino , Lactente , Suínos/crescimento & desenvolvimento , Arginina/administração & dosagem , Suplementos Nutricionais , Aumento de Peso/efeitos dos fármacos , Fenômenos Fisiológicos da Nutrição Animal/efeitos dos fármacos
2.
Tese em Português | VETTESES | ID: vtt-218025

Resumo

O objetivo desse trabalho foi investigar características alternativas indicadoras de habilidade materna passíveis de utilização em programas de melhoramento genético de suínos que impactem positivamente no peso e qualidade dos leitões desmamados por fêmea ao ano. Informações de 4.627 leitegadas e 2.058 fêmeas das raças Large White e Landrace foram avaliadas através de abordagem Bayesiana. Foram propostas seis características alternativas as quais foram avaliadas juntamente com outras três tradicionais características de tamanho de leitegada. O grupo de características alternativas foi formado pelas medidas de ganho de peso médio diário do nascimento a desmama da leitegada biológica e da leitegada recebida, peso médio de desmame da leitegada biológica e leitegada recebida, peso total produzido da leitegada do nascimento ao desmame e potenciais de desmamados, calculado como a porcentagem de leitões desmamados do total de leitões recebidos no início do período de lactação. As herdabilidades estimadas para as características alternativas são baixas (0,02 a 0,06). A associação complexa entre as características indicadoras de habilidade materna e tamanho de leitegada foi demonstrada pelas diferenças observadas entre os tipos de mensuração e raças. Além disso, observou-se uma possível influência do método de amamentação cruzada da leitegada empregado. A inserção de características de desempenho da leitegada (alternativas) como ganho médio diário e peso médio desmamado em programas de melhoramento genético suíno é viável e possivelmente refletirá na melhoria da qualidade do leitão desmamado e no peso desmamado por fêmea ao ano.


The aim was to investigate alternative traits to predict maternal ability that could be used in swine breeding programs to positively impact the weight and quality of piglets weaned per female per year. Information from 4,627 litters and 2,058 females of Large White and Landrace breeds were evaluated using Bayesian approach. Six alternative traits were proposed, which were evaluated together with three other traditional litter size traits. The alternative group was formed by the measures of average daily weight gain from birth to weaning from the received litter and the biological litter, average weaning weight of the received litter and the biological litter, total litter weight produced from birth to weaning and potential of weaned, calculated as the percentage of piglets weaned from the total piglets received at the beginning of the lactation period. The estimated heritabilities for the alternative traits are low (0.02 to 0.06). The complex association between traits indicating maternal ability and litter size was demonstrated by the differences observed between measurement types and breeds. In addition, a possible influence of the cross-fostering method was observed. The insertion of litter performance traits (alternatives) such as average daily gain and weaned weight in swine breeding programs is feasible and will possibly reflect in the improvement of the quality of the weaned piglet and the weight weaned per female per year.

3.
Arq. bras. med. vet. zootec ; 66(2): 510-518, Jan.-Apr. 2014. graf, tab
Artigo em Inglês | VETINDEX | ID: vti-10757

Resumo

The aim of the study was to evaluate the behaviour, pre-weaning survival rate and growth performance of low birth weight (BW) piglets cross-fostered with piglets of higher weights. Piglets were transferred to 60 foster sows, and divided in three groups (G; n=20): G1- 12 low BW piglets (0.80 - 1.25kg); G2- six low BW piglets and six intermediate BW piglets (1.40 - 1.60kg), and G3- six low BW piglets and six high BW piglets (>1.70kg). For the analysis, groups G2 and G3 were subdivided in LG2 (six G2 light piglets); IG2 (six G2 intermediate piglets), LG3 (six G3 light piglets), and HG3 (six G3 heavy piglets). Behavioural observations were carried out on days 1, 2, 4 and 6 (visual direct observation) and on days 3 and 5 (video recording) after birth. The percentage of missed nursings was higher in LG3 piglets than in LG1, IG2 and HG3 piglets, on days 1 and 2. On day 4, light piglets (LG1, LG2 and LG3) missed more nursings than IG2 and HG3 piglets. On day 3, video recording showed a higher percentage of missed nursings in LG1, LG2, and LG3 piglets as compared to HG3 piglets. On day 1, the number of fights during nursing was higher in IG2 than in LG1 and LG3 piglets. Also on day 1, number of fights and percentage of piglets engaged in fights, during 15min after nursing, were higher in LG1, LG3 and HG3 than in LG2 piglets. More playful behaviours were observed on day 2 in IG2 and HG3 piglets compared to LG1, LG2 and LG3 piglets. Light piglets (LG1, LG2, and LG3) presented similar body weight on days 4, 8, 12 and 16 after birth, regardless of being mixed with piglets of higher weights or not; however, the survival rate until day 16 was most compromised in LG3 piglets compared to the other groups. Despite the lack of influence of littermates' weight on the growth of low BW piglets, their survival rate indicates that they should not be mixed with high BW piglets.(AU)


O objetivo do estudo foi avaliar o comportamento, a taxa de sobrevivência pré-desmame e o desempenho de crescimento de leitões leves ao nascer uniformizados com leitões de maior peso ao nascer (PN). Os leitões foram transferidos para 60 fêmeas e divididos em três grupos (G; n=20): G1 - 12 leitões de baixo PN (0,80-1,25kg); G2 - seis leitões de baixo PN e seis com PN intermediário (1,40-1,60kg); e G3 - seis leitões de baixo PN e seis leitões pesados (>1,70kg). Para a análise, os grupos G2 e G3 foram subdivididos em LG2 (seis G2 leitões leves); IG2 (seis G2 leitões de peso intermediário); LG3 (seis G3 leitões leves) e HG3 (seis G3 leitões pesados). Observações de comportamento foram realizadas nos dias 1, 2, 4 e 6 (observações visuais diretas) e nos dias 3 e 5 (gravações) após o nascimento. A porcentagem de mamadas perdidas foi maior no grupo LG3 quando comparado aos grupos LG1, IG2 e HG3, nos dias 1 e 2. No dia 4, leitões leves (LG1, LG2 e LG3) perderam maior número de mamadas do que os grupos IG2 e HG3. No dia 3, a gravação mostrou maior porcentagem de perda de mamadas nos grupos LG1, LG2 e LG3 do que no grupo HG3. No dia 1, o número de brigas durante a mamada foi maior nos grupos IG2 do que nos grupos LG1 e LG3. Também no dia 1, o número de brigas e porcentagem de leitões envolvidos em brigas, durante 15 minutos após a mamada, foi maior nos grupos LG1, LG3 e HG3 do que no grupo LG2. Brincadeiras foram mais observadas no dia 2 nos grupos IG2 e HG3 quando comparado aos grupos LG1, LG2 e LG3. Leitões leves (LG1, LG2 e LG3) apresentaram peso semelhante nos dias 4, 8, 12 e 16 após o nascimento, independentemente de serem misturados ou não com leitões pesados. No entanto, a taxa de sobrevivência até o dia 16 foi mais comprometida nos leitões do grupo LG3 do que nos outros grupos. Apesar da falta de influência do peso das leitegadas no crescimento de leitões de baixo PN, a taxa de sobrevivência indicou que estes não devem ser misturados com leitões de maior PN.(AU)


Assuntos
Animais , Suínos/crescimento & desenvolvimento , Tamanho da Ninhada de Vivíparos , Peso-Idade , Distribuição por Idade , Taxa de Sobrevida , Peso Corporal , Grupos de População Animal
4.
Acta sci. vet. (Impr.) ; 41: 01-07, 2013.
Artigo em Inglês | LILACS-Express | VETINDEX | ID: biblio-1457148

Resumo

Background: In tropical and subtropical regions, temperature values above thermoneutrality for pigs are often experienced and lactating sows maintained outside the thermal comfort zone might have their performance compromised. The use of ventilation or evaporative cooling to maintain animal thermoregulation might be alternatives to minimise animal production losses. The objective of this study was to evaluate the influence of three different systems for the control of environmental temperature on the productivity of sows and their litters. Materials, Methods & Results: Three systems of environmental temperature control were evaluated: air-conditioned: AC (n = 79), with farrowing facility temperature controlled by a system of evaporative cooling pads combined with negative pressure ventilation; snout cooler: SC (n = 82), with a cold air outlet directed toward sows, combined with management of curtains; and management of curtains: MC (n = 83). Piglet weight was recorded at cross-fostering, and at 14 and 20 days of age. Temperature (TEMP) and relative humidity (RH) were measured daily at five time points (8:00, 10:00, 12:00, 14:00 and 16:00 h). The variables concerning the sows were analysed with the MIXED procedure of SAS, including the fixed effect of system and random effects of period and period × system interaction. The weight of piglets, TEMP and RH inside the farrowing


Background: In tropical and subtropical regions, temperature values above thermoneutrality for pigs are often experienced and lactating sows maintained outside the thermal comfort zone might have their performance compromised. The use of ventilation or evaporative cooling to maintain animal thermoregulation might be alternatives to minimise animal production losses. The objective of this study was to evaluate the influence of three different systems for the control of environmental temperature on the productivity of sows and their litters. Materials, Methods & Results: Three systems of environmental temperature control were evaluated: air-conditioned: AC (n = 79), with farrowing facility temperature controlled by a system of evaporative cooling pads combined with negative pressure ventilation; snout cooler: SC (n = 82), with a cold air outlet directed toward sows, combined with management of curtains; and management of curtains: MC (n = 83). Piglet weight was recorded at cross-fostering, and at 14 and 20 days of age. Temperature (TEMP) and relative humidity (RH) were measured daily at five time points (8:00, 10:00, 12:00, 14:00 and 16:00 h). The variables concerning the sows were analysed with the MIXED procedure of SAS, including the fixed effect of system and random effects of period and period × system interaction. The weight of piglets, TEMP and RH inside the farrowing

5.
R. bras. Saúde Prod. Anim. ; 14(1): 142-148, Jan-Mar. 2013. graf
Artigo em Inglês | VETINDEX | ID: vti-695405

Resumo

The high number of piglets born alive from hiperprolifics sows increases the variability of weight at birth and made many producers practice cross-fostering management, which consists in standardization of weight and number of piglets according to the sow ability. To evaluate the effect of cross-fostering on performance and mortality occurrence of piglets, historical data were studied from two producers of the Midwest region of Santa Catarina-Brazil. Were weighed 1440 piglets at birth, weaning and 37 days post weaning from 130 commercial sows of Agroceres PIC®. The adjusted weights at 21 and 58 days old and their respective gain were submitted to multiple regression analysis using the GLM procedure of SAS Statistical Software (2005), and occurrence of mortality was studied by GENMOD procedure. For performance traits were considered fixed effects the cross-fostering, contemporary group and covariables the birth weight or weaning, the number of piglets after equalization, number of weaned piglets, linear and quadratic effects of sow parity; the weight at birth were included as covariable for occurrence of mortality. Cross-fostered piglets weighed 207 grams less than biological piglets (P<0.01) and had lesser mortality between lightest piglets. However, the littermate equalization did not promote differences in growth period between cross-fostered and biological piglets.(AU)


O aumento do número de leitões nascidos vivos de fêmeas hiperprolíficas aumenta a variabilidade do peso ao nascer e faz muitos produtores praticarem a equalização de leitegadas, que consiste na uniformização do peso e número de leitões de acordo com a capacidade da matriz. Com o objetivo de avaliar o efeito da equalização de leitegadas sobre o crescimento e mortalidade de leitões, estudaram-se dados históricos de duas unidades produtoras de leitões da região centro-oeste de Santa Catarina. Foram pesados 1440 leitões ao nascer, desmame e saída de creche, nascidos de 130 matrizes comerciais Agroceres PIC®. Os pesos ajustados aos 21 e 58 dias de idade e os respectivos ganhos médios diários foram submetidos à análise de regressão múltipla por meio do procedimento GLM do programa estatístico SAS (2005), e a ocorrência de mortalidade foi estudada pelo procedimento GENMOD do mesmo programa. Foram considerados como efeitos fixos a transferência e grupo de contemporâneos e como covariáveis o peso ao nascer ou desmame, número de leitões após equalização e número de leitões desmamados, além dos efeitos linear e quadrático da ordem de parto da matriz; no estudo da ocorrência de mortalidade o peso ao nascer foi considerado como covariável. Os leitões adotivos pesaram 207 gramas a menos que leitões biológicos no período da maternidade (P<0,01) e maior sobrevivência entre os leitões leves. No entanto, o efeito da equalização não promoveu diferenças no período de creche entre os leitões adotivos e aqueles criados por suas mães biológicas.(AU)


Assuntos
Animais , Recém-Nascido , Suínos/embriologia , Suínos/crescimento & desenvolvimento , Criação de Animais Domésticos/tendências , Parto
6.
Rev. bras. saúde prod. anim ; 14(1): 142-148, Jan-Mar. 2013. graf
Artigo em Inglês | VETINDEX | ID: biblio-1493200

Resumo

The high number of piglets born alive from hiperprolifics sows increases the variability of weight at birth and made many producers practice cross-fostering management, which consists in standardization of weight and number of piglets according to the sow ability. To evaluate the effect of cross-fostering on performance and mortality occurrence of piglets, historical data were studied from two producers of the Midwest region of Santa Catarina-Brazil. Were weighed 1440 piglets at birth, weaning and 37 days post weaning from 130 commercial sows of Agroceres PIC®. The adjusted weights at 21 and 58 days old and their respective gain were submitted to multiple regression analysis using the GLM procedure of SAS Statistical Software (2005), and occurrence of mortality was studied by GENMOD procedure. For performance traits were considered fixed effects the cross-fostering, contemporary group and covariables the birth weight or weaning, the number of piglets after equalization, number of weaned piglets, linear and quadratic effects of sow parity; the weight at birth were included as covariable for occurrence of mortality. Cross-fostered piglets weighed 207 grams less than biological piglets (P<0.01) and had lesser mortality between lightest piglets. However, the littermate equalization did not promote differences in growth period between cross-fostered and biological piglets.


O aumento do número de leitões nascidos vivos de fêmeas hiperprolíficas aumenta a variabilidade do peso ao nascer e faz muitos produtores praticarem a equalização de leitegadas, que consiste na uniformização do peso e número de leitões de acordo com a capacidade da matriz. Com o objetivo de avaliar o efeito da equalização de leitegadas sobre o crescimento e mortalidade de leitões, estudaram-se dados históricos de duas unidades produtoras de leitões da região centro-oeste de Santa Catarina. Foram pesados 1440 leitões ao nascer, desmame e saída de creche, nascidos de 130 matrizes comerciais Agroceres PIC®. Os pesos ajustados aos 21 e 58 dias de idade e os respectivos ganhos médios diários foram submetidos à análise de regressão múltipla por meio do procedimento GLM do programa estatístico SAS (2005), e a ocorrência de mortalidade foi estudada pelo procedimento GENMOD do mesmo programa. Foram considerados como efeitos fixos a transferência e grupo de contemporâneos e como covariáveis o peso ao nascer ou desmame, número de leitões após equalização e número de leitões desmamados, além dos efeitos linear e quadrático da ordem de parto da matriz; no estudo da ocorrência de mortalidade o peso ao nascer foi considerado como covariável. Os leitões adotivos pesaram 207 gramas a menos que leitões biológicos no período da maternidade (P<0,01) e maior sobrevivência entre os leitões leves. No entanto, o efeito da equalização não promoveu diferenças no período de creche entre os leitões adotivos e aqueles criados por suas mães biológicas.


Assuntos
Animais , Recém-Nascido , Criação de Animais Domésticos/tendências , Suínos/crescimento & desenvolvimento , Suínos/embriologia , Parto
7.
Acta sci. vet. (Impr.) ; 41: Pub. 1111, 2013. tab
Artigo em Inglês | VETINDEX | ID: biblio-1372533

Resumo

Background: In tropical and subtropical regions, temperature values above thermoneutrality for pigs are often experienced and lactating sows maintained outside the thermal comfort zone might have their performance compromised. The use of ventilation or evaporative cooling to maintain animal thermoregulation might be alternatives to minimise animal production losses. The objective of this study was to evaluate the influence of three different systems for the control of environmental temperature on the productivity of sows and their litters. Materials, Methods & Results: Three systems of environmental temperature control were evaluated: air-conditioned: AC (n = 79), with farrowing facility temperature controlled by a system of evaporative cooling pads combined with negative pressure ventilation; snout cooler: SC (n = 82), with a cold air outlet directed toward sows, combined with management of curtains; and management of curtains: MC (n = 83). Piglet weight was recorded at cross-fostering, and at 14 and 20 days of age. Temperature (TEMP) and relative humidity (RH) were measured daily at five time points (8:00, 10:00, 12:00, 14:00 and 16:00 h). The variables concerning the sows were analysed with the MIXED procedure of SAS, including the fixed effect of system and random effects of period and period × system interaction. The weight of piglets, TEMP and RH inside the farrowing facility were analysed as repeated measures using the MIXED procedure. Means were compared with the Tukey-Kramer test. The weight of sows at farrowing, the number of cross-fostered piglets and weight of piglets at cross-fostering were similar among the systems (P > 0.10), with overall means of 241.2 kg, 11.4 piglets and 1.4 kg, respectively. In the AC system, TEMP (23.1ºC) was on average lower (P < 0.05) than in the SC (26.8ºC) and MC (26.8ºC) systems. Overall, higher RH (P < 0.05) was observed in AC (88.3%) than in SC (74.5%) and MC (73.6%) systems. Sows of the MC system had a lower daily feed intake (DFI) than AC sows (P < 0.05) and tended (P = 0.082) to have lower DFI than SC sows (4.7 vs. 5.2 vs. 5.1 kg for MC, AC and SC sows, respectively). There were no differences (P > 0.10) among AC, SC and MC systems regarding sow weight loss during lactation (3.3% vs. 5.0% vs. 4.0%) and weaning-to-estrus interval (4.5 d vs. 5.0 d vs. 4.5 d). The number of weaned piglets was similar among the systems (P > 0.10) with an overall mean of 10.8 weaned piglets. The weight of piglets at weaning tended to be lower (P = 0.083) in the MC than the SC system (5,977 g vs. 6,209 g), whereas piglets of the AC system had an intermediate weight (6,152 g). Discussion: The temperature in SC and MC systems was above the upper critical temperature for sows, mainly between 12:00 and 16:00, which could explain the lower feed intake of sows in the MC system. The higher feed intake of SC sows compared to MC sows is probably related to the microenvironment created by the fresh air over the heads of SC sows improving their thermoregulation and comfort, and preventing a reduction in feed intake. The AC system was the most efficient in reducing the temperature in the farrowing facility. However, the higher feed intake of AC sows compared to that of MC sows did not result in differences in piglet weight. As the temperature in the AC system was close to the lower critical temperature for the piglets, heating provided to piglets was probably insufficient and they required an extra energetic demand for heat production to maintain their body temperature. The higher weight of SC piglets is probably explained by the higher feed intake of sows and by the fact that temperature in the farrowing facility did not decrease as in the AC system.


Assuntos
Animais , Feminino , Suínos , Temperatura , Eficiência
8.
Acta sci. vet. (Impr.) ; 39(1): 01-06, 2011. tab
Artigo em Português | VETINDEX | ID: biblio-1456840

Resumo

Crossfostering is the transference of piglets to either equalize litter size or to formation of homogeneous litters according to the birth weight. It is used in order to improve survival rate and weight gain of piglets during lactation. Several aspects influence the results of crossfostering, as the moment when this management is performed, size of the piglets and parity order (PO) of biological and adoptive dams. Crossfostering should be performed, preferably between six and 24 h after farrowing, before teat order has been established and so that piglets can absorb the maximum of colostrum immunoglobulins from their biological dams. Performance and viability of piglets during lactation depends on the quality of colostrum and milk production of biological and adoptive dam, which varies according to PO. The aim of the experiment was to assess the performance of biological and adopted piglets crossfostered in PO 1 and PO 5 females.[...]


Assuntos
Animais , Leite/metabolismo , Suínos/classificação , Colostro/metabolismo , Parto/genética
9.
Acta sci. vet. (Online) ; 39(1): 01-06, 2011. tab
Artigo em Português | VETINDEX | ID: vti-381308

Resumo

Crossfostering is the transference of piglets to either equalize litter size or to formation of homogeneous litters according to the birth weight. It is used in order to improve survival rate and weight gain of piglets during lactation. Several aspects influence the results of crossfostering, as the moment when this management is performed, size of the piglets and parity order (PO) of biological and adoptive dams. Crossfostering should be performed, preferably between six and 24 h after farrowing, before teat order has been established and so that piglets can absorb the maximum of colostrum immunoglobulins from their biological dams. Performance and viability of piglets during lactation depends on the quality of colostrum and milk production of biological and adoptive dam, which varies according to PO. The aim of the experiment was to assess the performance of biological and adopted piglets crossfostered in PO 1 and PO 5 females.[...](AU)


Assuntos
Animais , Suínos/classificação , Leite/metabolismo , Parto/genética , Colostro/metabolismo
10.
Tese em Português | VETTESES | ID: vtt-204841

Resumo

A introdução de novas linhagens de camundongos em biotérios deve ser realizada com cautela devido aos riscos de introdução de doenças na colônia, motivo pelo qual alguns biotérios adotam como padrão introduzir novos animais somente após o processo de rederivação, que pode ser realizado por transferência embrionária, histerectomia ou cross-fostering. A rederivação é adotada para diversas espécies de animais de laboratório e constitui uma forma de reduzir o risco de surtos de doenças em um biotério com a consequente interferência na pesquisa e perdas, tanto do status sanitário como do bem-estar dos animais. Dentre esses métodos, a transferência de embriões nos estágios de pré-implantação é considerada mais segura que os outros métodos utilizados para se rederivar linhagens de camundongos por reduzir os riscos da transmissão vertical de patógenos. Essa técnica é adotada em diversos biotérios internacionais, porém não é rotina em biotérios do Brasil. O objetivo desse trabalho foi implantar a técnica de rederivação por transferência de embriões no estágio de duas células, no biotério de camundongos livres de patógenos específicos (SPF) do Departamento de Imunologia do Instituto de Ciências Biomédicas da Universidade de São Paulo. As transferências embrionárias foram realizadas para introdução de linhagens de camundongos procedentes de diferentes biotérios convencionais sem barreiras. Os embriões foram obtidos pelos métodos naturais, por meio do acasalamento das fêmeas doadoras superovuladas, com machos de genótipo ou fundo genético igual. Os embriões foram coletados por flushing e lavados em meio estéril. Realizou-se a transferência de embriões no estágio de duas células para fêmeas receptoras livres de patógenos específicos (SPF), pseudoprenhas no 0,5 dia pós coito (d.p.c.). Todos os procedimentos cirúrgicos foram realizados em condições assépticas. Total de 881 embriões, destes, 625 foram transferidos para rederivação de 18 linhagens de camundongos. Nasceram 148 filhotes vivos, dos quais 140 foram desmamados. Os seguintes patógenos foram eliminados pela técnica: vírus da hepatite murina, norovírus, Corynebacterium kutscheri, Staphylococcus aureus, Streptococcus beta hemolítico, Bordetella bronchiseptica e protozoários intestinais. Os dados apresentados foram obtidos da rotina do biotério num período de três anos. A implantação da técnica possibilitou a introdução de novas linhagens na criação, em condições sanitárias satisfatórias, com a consequente disponibilização de modelos animais com nível sanitário adequado à experimentação para a comunidade científica.


The introduction of new strains of mice should be performed carefully to avoid breaking sanitary barriers of specific pathogen free (SPF) animal facilities. In order to meet this need, animals should be rederived by embryo transfer, hysterectomy or cross-fostering and then maintained under strict biosecurity practices. Rederivation is a technique used in different species of laboratory animals to protect them from infectious agents, minimize risks of disease outbreaks and thus avoid research interference caused by loss of the health status and welfare of the animals. Among these techniques, embryo transfer at two cell stage should rather be implemented because it avoids post implantational vertical transmissions of infections. It is routine to introduce animals by embryo transfer in most animal facilities in the United States of America and Europe, however it is not seen in Brazilians rodents vivariums. The objective was to implement mice embryo transfer technique in the animal facility of the Department of Immunology of the Institute of Biomedical Science of the University of Sao Paulo, Brazil. Embryo transfers were performed to rederive strains of mice received from different sources. Fertilized eggs at two-cell stage were obtained by mating superovulated females with fertile males that had either the same genotype or the same genetic background. Embryos were collected by flushing of the oviducts and washed in sterile medium. Under general anesthesia, embryos were transferred into the oviducts of specific pathogen free (SPF) pseudo pregnant female mice at 0,5 - day post coitus (d.p.c.). All the surgical procedures were performed under asseptic conditions. Total of 881 embryos, out of these, 625 embryos at two-cell stage were transfered to rederive 18 mouse strains. It was born 148 pups, of which 140 were reared. The following mouse pathogens were eliminated by embryo transfer technique: Mouse hepatitis virus, Norovirus, Corynebacterium kutscheri, Staphylococcus aureus, Beta-Haemolytic Streptococci, Bordetella bronchiseptica and intestinal protozoa. Data were collected from routine laboratory in a period of two years. The improvement in the microbiological status of mice allowed their expansion in our SPF facility and the distribution of better models to the scientific community.

11.
Arq. bras. med. vet. zootec ; 63(5): 1073-1078, 2011. ilus
Artigo em Português | VETINDEX | ID: vti-1065

Resumo

Nove fêmeas de quinto parto (OP5) foram imunizadas com 4mg e 2mg de albumina sérica bovina (BSA) aos 70 e 100 dias de gestação, respectivamente. A uniformização da leitegada foi realizada 4,9±1,9h após o nascimento, antes de os leitões efetuarem a primeira mamada. As leitegadas foram compostas por cinco leitões biológicos (LB) e cinco leitões adotados (LA), com pesos semelhantes ao nascimento. Foram coletadas amostras de sangue dos leitões ao nascimento e 24h após, das fêmeas ao pós-parto e de colostro de cada grupo de tetos ao parto e 24h após. As amostras de soro e colostro foram quantificadas para IgG pelo ELISA indireto. A densidade ótica de IgG anti-BSA (DOIgG-BSA) dos leitões (24h de vida) foi correlacionada com a das fêmeas. A DOIgG-BSA entre LB e LA foi semelhante, assim como entre os grupos de tetos, ao parto e 24h após. Entretanto, ocorreu redução na DOIgG-BSA do parto até 24h após. LB e LA absorveram a mesma quantidade de IgG via colostro, quando a uniformização foi realizada até 5h pós-parto, independentemente do teto em que os leitões mamaram, uma vez que esses possuem a mesma concentração de IgG.(AU)


Nine sows of fifth parity (PO5) were immunized with 4mg and 2mg of bovine serum albumin (BSA) at 70 and 100d of gestation, respectively. Cross fostering was performed 4.9±1.9h after birth, before piglets had their first suckling. Litters were composed of five biological piglets (BP) and five adopted piglets (AP), with similar weight at birth. Blood samples were collected from piglets (at birth and at 24h of life) and from females (after farrowing) and colostrum from each group of teats (at farrowing time and after 24h). Samples of serum and colostrum were quantified to IgG by indirect ELISA. Optical density of IgG anti-BSA (ODIgG-BSA) from piglets (24h of life) was correlated with dams. ODIgG-BSA was similar among BP and AP, as well as among pairs of teats (at farrowing time and after 24h). However, there was a decrease in ODIgG-BSA from farrowing up to 24h after birth. BP and AP absorbed the same amount of IgG via colostrum, when cross fostering was evaluated 5h after farrowing, regardless of the teat suckled, since these have the same concentration of IgG.(AU)


Assuntos
Animais , Feminino , Suínos , Colostro/imunologia , Imunoglobulina G/análise , Soroalbumina Bovina/administração & dosagem , Anticorpos , Trabalho de Parto Induzido/veterinária , Imunidade Celular
12.
Acta sci. vet. (Online) ; 41: 01-07, 2013.
Artigo em Inglês | VETINDEX | ID: vti-480243

Resumo

Background: In tropical and subtropical regions, temperature values above thermoneutrality for pigs are often experienced and lactating sows maintained outside the thermal comfort zone might have their performance compromised. The use of ventilation or evaporative cooling to maintain animal thermoregulation might be alternatives to minimise animal production losses. The objective of this study was to evaluate the influence of three different systems for the control of environmental temperature on the productivity of sows and their litters. Materials, Methods & Results: Three systems of environmental temperature control were evaluated: air-conditioned: AC (n = 79), with farrowing facility temperature controlled by a system of evaporative cooling pads combined with negative pressure ventilation; snout cooler: SC (n = 82), with a cold air outlet directed toward sows, combined with management of curtains; and management of curtains: MC (n = 83). Piglet weight was recorded at cross-fostering, and at 14 and 20 days of age. Temperature (TEMP) and relative humidity (RH) were measured daily at five time points (8:00, 10:00, 12:00, 14:00 and 16:00 h). The variables concerning the sows were analysed with the MIXED procedure of SAS, including the fixed effect of system and random effects of period and period × system interaction. The weight of piglets, TEMP and RH inside the farrowing


Background: In tropical and subtropical regions, temperature values above thermoneutrality for pigs are often experienced and lactating sows maintained outside the thermal comfort zone might have their performance compromised. The use of ventilation or evaporative cooling to maintain animal thermoregulation might be alternatives to minimise animal production losses. The objective of this study was to evaluate the influence of three different systems for the control of environmental temperature on the productivity of sows and their litters. Materials, Methods & Results: Three systems of environmental temperature control were evaluated: air-conditioned: AC (n = 79), with farrowing facility temperature controlled by a system of evaporative cooling pads combined with negative pressure ventilation; snout cooler: SC (n = 82), with a cold air outlet directed toward sows, combined with management of curtains; and management of curtains: MC (n = 83). Piglet weight was recorded at cross-fostering, and at 14 and 20 days of age. Temperature (TEMP) and relative humidity (RH) were measured daily at five time points (8:00, 10:00, 12:00, 14:00 and 16:00 h). The variables concerning the sows were analysed with the MIXED procedure of SAS, including the fixed effect of system and random effects of period and period × system interaction. The weight of piglets, TEMP and RH inside the farrowing

13.
São Paulo; s.n; 10/11/2006. 329 p.
Tese em Português | VETTESES | ID: vtt-5409

Resumo

O presente estudo visou avaliar efeitos da I. carnea e de seus princípios ativos sobre a imunidade natural de ratos e, os efeitos de sua administração durante a gestação ou lactação às mães e os possíveis efeitos imunotóxicos sobre os filhotes quando adultos. Nas o resíduo da planta (RAF) foi diluído na água de bebida nas doses-alvo de 3,0 e 15,0g/kg de folhas secas da planta, durante 14 e 21 dias e por via oral, por gavage, na dose de 15,0g/kg, durante 14 dias, para avaliação da atividade de macrófagos (MO) peritoneais e das inflamações crônica e aguda, induzidas pelo BCG e pela carragenina, respectivamente. Os princípios ativos (suainsonina e calisteginas B1, B2, B3 e C1) foram administrados isoladamente em ratas, nas mesmas concentrações presentes em 15,0g/kg do RAF, durante 14 dias, para então avaliar a atividade macrofágica. Em ratas prenhes ou lactantes empregaram-se as doses de 1,0; 3,0; 7,0 e 15,0g/kg do RAF, por gavage. Ainda no estudo perinatal, foram realizados o cross-fostering para observação da passagem transplacentária da suainsonina, a amniocentese e a coleta de leite para quantificação deste alcalóide. As proles foram avaliadas até os 70 dias de vida, para avaliação da atividade macrofágica e das inflamações crônica e aguda. Foram realizados ensaios de imunotoxicidade, (peso relativo de órgãos linfóides, resposta imune humoral e celular), em ratos jovens e adultos, tratados durante 14 dias. No final da experimentação foram coletados diferentes órgãos para o estudo histopatológico. Em relação à imunidade das ratas adultas houve aumento da fagocitose e da produção de peróxido de hidrogênio de MO, maior processo inflamatório crônico e supressão da resposta inflamatória aguda, apenas nas ratas tratadas com baixas doses do RAF. Dos alcalóides da I.carnea, apenas a suainsonina mostrou-se tóxica. Em relação às ninhadas de mães tratadas durante a gestação ou lactação, verificou-se menor peso ao nascimento e menor peso ao desmame, respectivamente. O emprego do cross-fostering evidenciou a passagem da suainsonina pela placenta, confirmada pela quantificação deste alcalóide no líquido amniótico. A suainsonina também foi quantificada no leite. Em relação à imunidade natural da prole de ratas tratadas durante a gestação ou lactação, não se observou alterações nos parâmetros avaliados, porém filhotes de ratas tratadas com a planta durante a lactação e desafiados com o BCG quando adultos, desenvolveram artrite. Nos ensaios imunotóxicos, ratos jovens apresentaram involução tímica, os adultos esplenomegalia e menor celularidade de medula óssea, e em todos os animais, aumento no título de anticorpos. Dos órgãos coletados, apenas o SNC não apresentou as degenerações vacuolares características da toxicose por I.carnea. Concluindo, baixas doses do RAF promovem aumento da atividade de MO. Dos alcalóides da planta, apenas a suainsonina mostrou-se tóxica. A suainsonina passa a barreira placentária, ocasionando ninhadas menores e com menor peso e, também é excretada no leite, ocasionando lesões degenerativas vacuolares, bem como alterações no desenvolvimento tímico, o que possivelmente resultou em autoimunidade quando do desafio imune na idade adulta. Finalmente, em ratos, mesmo em altas doses, não ocorre lesão vacuolar no SNC


The aim of this study was to evaluate the toxic effect of I. Carnea and its toxins on the immune system of rats, and to evaluate its effects on mothers and offspring when administered to dams during gestation or lactation. An alkaloid-rich plant extract (RAF) was added to drinking water to obtain doses equivalent to 3.0 and 15.0g/kg of dry leaves for 14 and 21 days, and a dose of 15.0 g/kg by gavage for 14 days. Macrophage activity (MO), and chronic and acute inflammation induced by BCG and carragenine, respectively, were evaluated. Each toxin in I. carnea (i.e., swainsonine and calystegines B1, B2, B3 and C1) was administered by gavage to female rats, in similar concentrations as contained in 15.0g/kg of RAF during 14 days to evaluate MO. The RAF was dosed by gavage in pregnant or nursing rats at 1.0, 3.0, 7.0 and 15.0g/kg. Cross-fostering was used to evaluate placental passage of swainsonine; swainsonine concentration was determined in amniotic fluid and in milk. On postpartum day 70 the litters were evaluated for MO and chronic and acute inflammation. Immunotoxic responses were evaluated in young and adult rats treated with RAF for 14 days. Tissue samples were then harvested for histopathology. The immune function of adult rats was enhanced by lower doses of the RAF. Phagocytosis and hydrogen peroxide production were improved, and there was enhancement of chronic immunity, but suppression of acute inflammatory responses. Among the I.carnea alkaloids, only swainsonine showed toxicity. The litters of dams treated with swainsonine during gestation or lactation showed a reduction in body weight at birth and after lactation, respectively. Swainsonine clearly passed through the placenta, and was found in amniotic fluid, and in milk. There were no effects on the immunity of litters from mothers treated during gestation or lactation. However, pups from mothers dosed with swainsonine during lactation had an increased occurrence of arthritis. Further, young rats showed thymus atrophy, whereas adults developed splenomegaly and reduced bone marrow cellularity. Finally, animals of all ages showed enhanced antibody titers. Only CNS tissue did not have the characteristic vacuolar degeneration typical of I. Carnea toxicosis. In conclusion, low doses of RAF enhanced MO activity. Among the I. Carnea alkaloids, only swainsonine showed toxicity. Swainsonine passed the placental barrier, resulting in smaller litters with diminished birth weights. Swainsonine was also excreted in milk, resulting in vacuolar lesions in pups, as well as thymus atrophy, which could cause autoimmunity in adulthood. Finally, even with higher doses, CNS tissue in rats is resistant to the toxic effects of swainsonine

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