Patricia Pauletti

IgG absorption by Santa Ines lambs fed Holstein bovine colostrum or Santa Ines ovine colostrum

The objective of this study was to evaluate the immunoglobulin G (IgG) absorption by Santa Ines lambs under two colostrum management systems usually used by producers. Twenty-seven Santa Ines newborn lambs received two meals of 250 ml of bovine colostrum from Holstein cows (BC group) or ovine colostrum from Santa Ines ewes (OC group) at 0 and 6 h of life. Pools of BC and OC were analyzed by radial immunodiffusion to quantify IgG. Results are expressed as least-square means and standard errors of mean (means ± s.e.m.). The concentration of IgG in bovine and ovine pools averaged 115.7 ± 20.5 and 48.1 ± 5.0 mg/ml, respectively, levels of concentration found in similar regular colostrum managements. The efficiency of IgG absorption was evaluated under two aspects, maximum apparent efficiency of absorption and total apparent efficiency of absorption (AEAmax and AEAtotal, respectively). The AEAmax was calculated taking into account the mass of IgG ingested just in the first meal of colostrum at birth and the serum IgG concentration at 6 h while the AEAtotal took into account the serum IgG concentration at 24 h of life that reflects the first colostrum offered at birth and the second meal at 6 h. The IgG and apparent efficiency of absorption results were transformed into the square root and log base 10, respectively, and were presented as geometric least-square means. In BC, lower (P < 0.05) AEAmax and AEAtotal were verified (14.2% and 15.6%, respectively), in relation to OC (23.6% and 24.4%, respectively). Serum IgG concentrations at 24 h were significantly higher (P < 0.05) in BC (31.4 mg/ml, respectively) compared with OC (22.2 mg/ml, respectively). The results in this study confirm that there is a limitation to the process of IgG absorption by the enterocytes of newborn lambs, which determined a nonlinear behavior of passive immunity acquisition. Similar values of AEAmax and AEAtotal for the two sources of colostrum reveal that the process of IgG absorption from the first and second meals during the first 6 h of life did not change and indicates that the ingestion of a second feeding of quality colostrum can enhance the acquisition of immune protection of newborn lambs.

Flutuação das variáveis séricas em cabras e estudo comparativo da absorção de anticorpos em cabritos recém-nascidos utilizando colostro bovino e caprino

Objetivou-se determinar a flutuacao no nivel de anticorpos sericos em cabras nos periodos pre e pos-parto e a eficiencia do processo de aquisicao de imunidade passiva em cabritos recem-nascidos utilizando colostros bovino e caprino, visando a avaliacao de uma alternativa de manejo de colostro. Foram utilizadas 18 cabras e suas respectivas crias, num total de 33 animais. A coleta de sangue das cabras foi iniciada 45 dias antes da data prevista para o parto e foi realizada em intervalos de cinco dias ate o 5o dia apos o parto. Os cabritos foram distribuidos em dois grupos: um grupo recebeu colostro caprino e o outro colostro bovino. As coletas de sangue foram feitas as 0, 12, 24 e 48 horas e aos 5, 10, 15, 17, 20, 25, 30, 35, 40, 50 e 60 dias de vida. Foram analisadas as concentracoes sericas de proteina total e imunoglobulinas, alem da concentracao de imunoglobinas no colostro. O delineamento experimental foi o inteiramente casualizado e as variaveis sericas analisadas como medidas repetidas. A ausencia de queda na concentracao serica de proteinas totais e imunoglobinas no periodo pre-parto indica que a mobilizacao de anticorpos para glândula mamaria ocorre em concentracoes que permitem o animal manter essas variaveis sem grandes alteracoes. No grupo que recebeu colostro bovino, a data de concentracao maxima de proteinas totais (7,16 ± 0,28 g/dL) foi verificada as 48,68 ± 0,70 horas de vida e a de imunoglobinas, as 48,75 ± 0,73 horas, com media de 37,56 ± 2,38 unidades ZST (turvacao por sulfato de zinco). No grupo que recebeu colostro caprino, os valores maximos de proteinas totais e imunoglobinas sericas ocorreram mais tardiamente, aos 20,05 ± 1,36 e 20,11 ± 1,72 dias de vida, com medias de 5,91 ± 0,22 g/dL e 28,17 ± 2,05 unidades ZST, respectivamente. O colostro caprino pode ser substituido pelo colostro bovino, que promove melhor aquisicao inicial de imunoglobulinas aos neonatos.

Absorção de anticorpos do colostro em bezerros: II. Estudo no intestino delgado distal

Com o objetivo de estudar a morfologia e determinar a localizacao da enzima fosfatase acida na regiao distal do intestino delgado de bezerros, do nascimento ao fechamento intestinal, foram coletadas amostras de 15 animais machos em tres idades: ao nascer sem que houvesse a ingestao de colostro; tres horas apos a ingestao da primeira refeicao de colostro e aos tres dias de idade. Observou-se, ao nascimento, a presenca de um grande vacuolo, que dominava todo o citoplasma das celulas epiteliais do jejuno distal e ileo. Apos a ingestao de colostro, verificou-se o acumulo de material absorvido nesses vacuolos. Foi detectada a reacao de fosfatase acida nas celulas absortivas de bezerros recem-nascidos, antes e apos a ingestao de colostro. Aos tres dias de idade, uma nova populacao de celulas geralmente nao vacuoladas, com sistema endocitico apical reduzido, foi observada recobrindo as vilosidades intestinais. Portanto, em bezerros a maturacao do epitelio absortivo do intestino delgado distal pode iniciar-se com o aumento da atividade enzimatica nos vacuolos absortivos, culminando com a rapida substituicao das celulas fetais por celulas diferenciadas nao pinociticas, o que determinaria o termino da transferencia de anticorpos maternos.

Quality of colostral passive immunity and pattern of serum protein fluctuation in newborn calves

Immunity acquired by newborn animals is known as passive immunity, and for ruminants, antibody acquisition depends on the ingestion and absorption of adequate amounts of immunoglobulins from colostrum. This study relates different initial levels of acquired passive protection and serum total protein (TP) and immunoglobulin G (IgG). Serum immunoglobulin concentration and total protein were evaluated for female Holstein calves in the first sixty days of life. Animals were separated into three groups according to their initial level of passive immunity: group 1- animals with a low level of passive immunity (below 20 mg mL-1); group 2- animals with a medium level (between 20 and 30 mg mL-1), and group 3- animals with a high level (above 30 mg mL-1). Serum total protein was determined through the biuret method and IgG was determined by radial immunodiffusion. Data were analyzed as a completely randomized, split-plot statistical design. Fluctuation of the variables along the experimental period was determined through non-linear regression by the DUD method (PROC NLIN - Non Linear SAS). Animals with low antibody acquisition started to produce antibodies earlier, reflecting a compensatory synthesis. On the other hand, animals having adequate levels exhibited an extended period of immunoglobulin catabolism and the beginning of the endogenous phase was delayed. Regardless initial levels, the fluctuations in IgG contents occurred around adequate physiological concentrations, ranging from 20 to 25 mg mL-1.

Levantamento do manejo de bovinos leiteiros recém-nascidos: desempenho e aquisição de proteção passiva

Objetivou-se identificar diferentes sistemas de manejo relacionados a morbidez e a mortalidade de bezerros de rebanhos leiteiros recem-nascidos, com enfase naqueles que envolvem o fornecimento de colostro. Foram utilizados 211 rebanhos na regiao Centro-sul do Estado de Minas Gerais, divididos em tres categorias de producao: categoria A, de 200 a 600 L/dia; categoria B, de 601 a 1000 L/dia; e categoria C, >1001 L/dia. Os produtores de leite foram entrevistados e responderam um questionario que abrangia os aspectos de producao, de manejo do rebanho e de desempenho dos recem-nascidos, tendo como pontos principais questoes referentes ao procedimento com o colostro, do manejo do bezerro e a mortalidade neonatal. Para a analise estatistica do levantamento, foram utilizados analise de variância e testes parametricos e nao-parametricos. Alem da divisao do trabalho em categorias de producao, os dados tambem foram redistribuidos e analisados considerando-se os indices de mortalidade dos bezerros alto e baixo. Com o resultado das analises procedidas, foram selecionadas as principais variaveis relacionadas a mortalidade: numero de animais; numero de vacas; numero de vacas lactantes; tempo de ocorrencia do primeiro aleitamento; quantidade de colostro na primeira refeicao; meio de fornecimento de colostro e de aleitamento apos o aparte; origem do leite; instalacoes; idade de acesso dos bezerros ao concentrado e periodo de desmame.

Colostral antibodies absorption in dairy calves: I. Proximal small intestine study

The objective of this study was to study the morphology and the localization of acid phosphatase at calves anterior small intestine, from birth to intestinal closure. Fifteen male dairy calves were used in this study, which were aged: unsuckled neonatal, three hours after colostrum ingestion and three days old. Vacuolated cells from duodenum to medium jejunum could be found in the newborn calf, which have shown absorbed material after colostrum ingestion. Changes at the morphological characteristics and the initiation of phosphatase acid reaction in lysosomes were observed in calves aged three days old. The three days old morphology can represent a different phase of epithelium cells maturation of calves small intestine indicating that the absorption process is dependent of the first generation of cells from this intestinal region.

Avaliação do fornecimento adicional de colostro para bezerros

The acquired immunity by newborns calves is dependent of ingestion and absorption of adequate quantity of colostral immunoglobulins. Supplemental pooled colostrum can be an important procedure to correct miscarried management. This study was performed to evaluate the effect of additional colostrum of super immunological quality at 12 hours of live on total serum protein and immunoglobulin G concentration in newborn calves. Fourty five newborn calves, separated in two treatments: Treatment 1 - additional colostrum 12 hours after birth (10% body weight) and Treatment 2 - control, were evaluated. According to the initial level of passive immunity, the animals were allocated to the groups described as follows: Group 1 (low level supplemented) IgG 20 mg/mL; Group 3 (low level control) IgG 20 mg/mL. The average concentration of pooled colostrum was 68,49 ± 4,21 mg/mL. In the animals with adequate levels of antibodies, despite of the additional colostrum, the concentrations were similar at all ages, without significant differences. However, in the group with low level of passive immunity the additional colostrum promoted a compensation effect with animals reaching the levels comparable with the ones with normal initial concentration of serum antibodies

IGF-I and IgG serum concentrations and in mammary secretions in cows treated with rbST prepartum

Foram utilizadas 42 vacas holandesas gestantes e multiparas, distribuidas ao acaso em dois grupos, com o objetivo de se determinar possiveis alteracoes na concentracao de IGF-I no colostro e nas secrecoes lacteas em resposta a mudancas na concentracao serica de IGF-I pre-parto, alem de se avaliar comparativamente a flutuacao serica pre-parto de IGF-I em relacao a IgG. O grupo tratado (n=21) recebeu 500 mg de somatotropina bovina recombinante (rbST) e o grupo controle (n=21) injecoes de vitamina E. Os tratamentos foram iniciados 35 dias pre-parto e repetidos a cada 14 dias ate o parto. Semanalmente, ate o parto, avaliou-se o escore corporal (EC) e coletaram-se amostras de sangue da veia mamaria. Foram amostrados o colostro e as secrecoes lacteas diariamente por sete dias pos-parto. O EC e a concentracao serica de acidos graxos nao-esterificados nao diferiram entre os grupos. O grupo rbST apresentou maiores concentracoes sericas de IGF-I na segunda e quarta semanas apos o inicio dos tratamentos, nao sendo encontradas diferencas entre os tratamentos ao parto. A concentracao de IGF-I foi superior no colostro das vacas tratadas com rbST, nao diferindo nas secrecoes subsequentes. As concentracoes sericas de IgG nao diferiram entre tratamentos durante todo o periodo experimental, assim como as do colostro e demais secrecoes lacteas. As concentracoes sericas de IGF-I e IgG variaram em funcao do periodo experimental, diferindo na amplitude e refletindo as grandes mudancas que ocorrem no ultimo mes de gestacao.

Colostral Immunoglobulins Absorption in Canchim and Nelore Calves

The efficiency of absorption of colostral immunoglobulins was evaluated in five Canchim and seven Nelore calves. They received colostrum pools with concentration of 70.20 ± 6.14 mg/mL through esofageal feeder at 2, 12, 24 and 36 hours after birth. The immunoglobulins concentrations of the pools were estimated through specific gravity and measured by radial immunodifusion. In the blood collection at birth and during the first 70 days of life, the total protein was assayed by biuret method and the immunoglobulins were assayed by radial immunodifusion. Data were analysed as a randomized split-plot statistical model. The highest concentrations of serum immunoglobulins and total protein were observed at 24 hours of age. No significant differences (P>0.5484) were observed for immunoglobulins concentration at 24 hours, with concentrations of 28.80 ± 7.24 mg/mL for Canchim and 27.32 ± 9.54 mg/mL for Nelore. The efficiency for immunoglobulins absorption was not significantly different (P>0.8715) between breeds, 64.04 ± 7.74% for Canchim and 62.30 ± 6.93% for Nelore. The lack of statistical significance persisted until the fourtieth day of life, period of maternal immunoglobulin predominance in the calves blood circulation. In the following period, from 40 to 70 days of age, phase of establishment of the endogenous production of immunoglobulin, differences in the IgG concentrations between the two groups were detected refflecting a possible breed effect difference. The process of colostral IgG absorption by the newborn calves was not affected by breed. The differences between breeds in the calves serum IgG were related to the phase of endogenous production of antibodies.

Intestinal histomorphology in Pseudoplatystoma fasciatum fed bovine colostrum as source of protein and bioactive peptides

Histological responses of the intestine are key for evaluating nutritional value of feed ingredients, since the organ is not only the chief site of feed digestion and nutrient absorption but also plays an important immunological function. Histomorphological alterations were evaluated in the intestine of juvenile striped catfish, Pseudoplatystoma fasciatum, fed diets containing 0 (control), 10 or 20% inclusion of lyophilized bovine colostrum (LBC), as source of protein or bioactive peptides, for either 30 or 60 days. Fish fed 20LBC presented at 60d a distinct pattern of macrophages and, some of them, higher number of vacuoles in rectum mucosa. The thickness of the muscle layer (TML) in fish fed diets with LBC was higher in the first portion of medium intestine than fish fed 0LBC. All fish presented significant increase of TML in the second portion of medium intestine along feeding period, but fish fed 20LBC had smaller values of TML than those of fish fed 0 and 10LBC which might be related to the higher intestinal coefficient found for this group. The TML of rectum was higher just for fish fed 10LBC. Dietary LBC altered morphometrical features of juvenile striped catfish intestine and possibly induced inflammatory reaction in the rectal mucosa, as a function of level of inclusion, feeding period and segment of intestine analyzed.