Ultrastructural characteristics of the intestinal mucosa of newborn calves fed in the second meal with colostrum enriched with IGF-I and IgG

Objetivou-se estudar os efeitos do fornecimento adicional de colostro de diferentes concentrações de IGF-I e IgG, às 12 horas de vida, sobre as características morfológicas dos enterócitos, bem como a relação entre a quantidade total de IGF-I ingerida e a altura dos microvilos intestinais de bezerros até as 72 horas de vida. Adotou-se o fornecimento prolongado de colostros de diferentes concentrações, incluindo colostro enriquecido com colostro liofilizado. Oitenta e dois bezerros da raça Holandesa receberam, ao nascimento, colostro com concentrações variáveis de IgG e, às 12 horas de vida, receberam três pools de colostro com densidades variáveis: colostro baixo - IgG e IGF-I inferiores a 30 mg/mL e 90,65 µg/L, respectivamente; alto - IgG e IGF-I superiores a 100 mg/mL e 344,02 µg/L, respectivamente; ou enriquecido de colostro liofilizado - IgG e IGF-I superiores a 120 mg/mL e 864,68 µg/L, respectivamente. Às 0, 10, 24, 36 e 72 horas de vida, coletaram-se amostras do duodeno, do jejuno (proximal, médio e distal) e do íleo para estudo ultraestrutural. Para determinação da altura dos microvilos, considerou-se o arranjo fatorial 3 × 3 + 1, correspondendo à quantidade total de IGF-I ingerida nas refeições de colostro (0-500, 500-1500, 1500-2500 µg), três idades de abate (10, 24 e 72 horas de vida) e o grupo controle (nascimento). As características morfológicas dos enterócitos diferiram conforme a idade e as quantidades de IgG e IGF-I disponibilizadas. A quantidade total de IGF-I ingerida teve efeito local positivo sobre a altura dos microvilos intestinais.The objective of this study was to evaluate the effects of additional colostrum with different IGF-I and IgG concentrations, at 12 hours of life, on morphological characteristics of enterocytes, as well as the relationship of total amount of IGF-I ingested on the microvillus height of the calves small intestine in the first 72 hours after birth. It was utilized prolonged supply of colostrum with different concentrations, including colostrum enriched with lyophilized colostrum. Eighty two Holstein calves received, at birth, colostrum with different IgG concentrations and, at 12 hours of life, they received three colostrum pools with variable density: low colostrum (IgG and IGF-I inferior to 30 mg/mL and 90.65 µg/L, respectively), high (IgG and IGF-I superior to 100 mg/mL and 344.02 µg/L, respectively), or enriched with lyophilized colostrum (IgG and IGF-I superior to 120 mg/mL and 864.68 µg/L, respectively). At 0, 12, 24, 36, and 72 hours after birth, duodenum, proximal, medium, and distal jejunum and ileum samples were collected for ultrastructural studies. It was employed a factorial arrangement 3 × 3 + 1, corresponding to the total amount of IGF-I ingested in colostrum meals (0-500, 500-1500, 1500-2500 µg), three slaughter ages (at 10, 24 and 72 hours of life) and control group (at birth) for determination of the microvillus height. Different morphologic characteristics of the enterocytes were observed as consequence of the age, IgG and IGF-I ingested. The total IGF-I amount ingested showed positively local effect on the microvillus height of the intestinal.FAPES

Efeito da suplementação de colostro enriquecido sobre as características morfológicas da mucosa intestinal de bezerros neonatos

Colostrum intake in neonatal calves is essential to obtain passive immunity and to influence metabolism, endocrine systems and the nutritional state. This study compares morphologic features of small intestine of calves fed a colostrum second meal at 12 hours of life with concentrations of immunoglobulin G (IgG) higher than 100mg mL  -1 (fresh colostrum or artificially prepared with addition of lyophilized colostrum) or smaller than 30mg mL-1. Twenty-four Holstein calves were randomly grouped according to concentration of IgG intake at 12 hours of life: low (less than 30mg mL-1); high (more than 100mg mL-1); plus lyophilized colostrum (more than 120mg mL-1). Intestinal tissue samples were collected at 0, 10, 24 and 72 hours after birth to evaluate morphology in segments: duodenum; proximal, middle and distal jejunum and ileum by examined with a scanning electron microscope. Villi of all segments showed more organized and uniform morphology characteristics with age. Only the animals fed colostrum with more than 100mg mL-1 of IgG at 24 hours after birth still showed the distal jejunum villi disoriented and more united in comparison to the other ages and groups. Intake of lyophilized colostrum affected ileum morphology along experiment period. Higher concentration of immunologic and bioactive elements supplied for longer period of time could be responsible for promoting effects on the enterocytes. Use of colostrum with high IgG concentrations, with or without addition of lyophilized colostrum, influenced the precocity of the intestinal mucosa development in newborn calves, suggesting earlier maturation of the mucosa

Taxa de crescimento e fragmentação Miofibrilar diferenciadas em ratos submetidos a restrição alimentar e realimentação

Feed regimens alter muscle growth rate, hence they might impact the proteolytic system involved in tenderization during meat conditioning. The aim of this project was to verify the effects of feed restriction regimens on muscular and animal growth and their impact on postmortem myofibrillar fragmentation. The regimens were: 1) Feeding ad libitum for 11 d (Al/2); 2) Feed restriction (60% of Net Energy for maintenance - NEm) for 11 d (Rt/2); 3) Ad libitum for 22 d (Al); 4) Ad libitum for 4 d and feed restriction (60% NEm) for 18 d (Rt); 5) Ad libitum for 19 d and 3 d of fast (Ft); 6) Feed restriction (60% NEm) for 11 d and ad libitum until 22 d (Ral). The regimens Al/2 and Rt/2 had different intestine weights (19.3 &plusmn; 1.1 and 15.8 &plusmn; 1.9 g, respectively; P < 0.07). At 22 d, Al animals had higher (P < 0.07) intestine weight (21.8 &plusmn; 3.8). Moreover, Ral animals had heavier intestine (19.9 &plusmn; 1.5) as compared to Rt (16.6 &plusmn; 1.6) or Ft (12.8 &plusmn; 1.9). The intestine/live weight percentage ratio was lower (P < 0.05) for Ft (6.3%) as compared to Al (8.4%) and to Ral (9.2%), but it was similar to Rt (7.6%). Liver weight (g) in the Ral (9.5 &plusmn; 1.1) did not differ from Al (10.7 &plusmn; 2.5) or Rt (8.5 &plusmn; 1.1), although the two latter were different (P < 0.05). There was an effect of feed restriction over muscle protein degradation verified by Myofibrillar Fragmentation Index (MFI). The animals at Rt, Ft or Ral showed the lowest MFI 0d (42 &plusmn; 1.9; 40 &plusmn; 2.7; 40 &plusmn; 3.6; respectively) and MFI 5d (77 &plusmn; 2.7; 74 &plusmn; 3.0; 74 &plusmn; 2.9; respectively) as compared to Al, whose indexes were 54 &plusmn; 3.0 and 82 &plusmn; 3.3. Even though the MFI 5d were lower for the restricted animals, the rates of fragmentation postmortem were higher. Feed restriction altered myofibrillar protein degradation, reflected in lower extended fragmentation of the myofibrils.Regimes alimentares alteram a taxa de crescimento muscular, e podem impactar o sistema proteolítico envolvido no amaciamento da carne durante maturação. O objetivo do trabalho foi verificar a existência de reflexo do regime alimentar sobre crescimento animal e muscular, e o impacto na fragmentação miofibrilar pós-morte. Os regimes foram: 1) Consumo ad libitum por 11 d (Al/2); 2) Restrição alimentar (60% energia de mantença - NEm) por 11 d (Rt/2); 3) Ad libitum por 22 d (Al); 4) Ad libitum por 4 d e restrição alimentar (60% NEm) por 18 d (Rt); 5) Ad libitum por 19 d e 3 d de jejum (Ft); 6) Restrição alimentar (60% NEm) por 11 d e ad libitum até 22 d (Ral). Os regimes Al/2 e Rt/2 apresentaram diferenças no peso de intestino (19,3 &plusmn; 1,1 e 15,8 &plusmn; 1,9 g, respectivamente; P < 0,07). Nos 22 d, o regime Al resultou em intestinos mais pesados (P < 0,07; 21,8 &plusmn; 3,8). Além disso, os animais do regime Ral tiveram maiores pesos de intestino (19,9 &plusmn; 1,5) comparados com Rt (16,6 &plusmn; 1,6) ou Ft (12,8 &plusmn; 1,9). A relação intestino/peso vivo foi menor (P < 0,05) para Ft (6,3%) comparado com Al (8,4%) e com Ral (9,2%), mas foi similar ao Rt (7,6%). O peso do fígado (g) nos animais do regime Ral (9,5 &plusmn; 1,1) não diferiu do regime Al (10,7 &plusmn; 2,5) ou Rt (8,5 &plusmn; 1,1), sendo que os dois últimos foram diferentes (P < 0,05). Houve efeito da restrição alimentar sobre a degradação da proteína muscular verificada pelo Índice de Fragmentação miofibrilar (MFI). Os animais de Rt, Ft ou Ral mostraram os menores valores de MFI 0d (42 &plusmn; 1,9; 40 &plusmn; 2,7; 40 &plusmn; 3,6; respectivamente) e MFI 5d (77 &plusmn; 2,7; 74 &plusmn; 3,0; 74 &plusmn; 2,9; respectivamente) comparados com Al onde os índices foram 54 &plusmn; 3,0 e 82 &plusmn; 3,3, respectivamente. Embora os animais que experimentaram alguma restrição alimentar tenham apresentado menor MFI 5d, as sua taxas de fragmentação pós-morte foram maiores. Restrição alimentar alterou a degradação da proteína miofibrilar, refletida na menor extensão da fragmentação das miofibrilas

Adição de probiótico ao leite integral ou sucedâneo e desempenho de bezerros da raça holandesa

The possibility of limiting antibiotics as growth stimulants for farm animals has produced a climate in which both consumers and manufacturers are looking for alternatives. Probiotics are being considered to exercise this role, and for this reason, 79 newborn Holstein calves were used to evaluate the effects of Lactobacillus acidophilus, Enterococcus faecium and Saccharomyces cerevisiae additions to whole milk or milk replacer. Calves were assigned at birth to a completely randomized design with a 3x2 factorial arrangement of treatments. Factors were: 1- whole milk: milk replacer at 3 days of age: milk replacer at 15 days of age; 2- probiotic supplementation or not. Animals remained on the trial until 15 days after weaning. Probiotic supplementation to calves fed milk replacer at 3 days of age improved preweaning daily body gain (with probiotic=0.22 vs. without probiotic=0.16 kg day-1) and feed conversion (2.62 vs. 3.85), as well as, postweaning feed conversion (1.66 vs. 2.03). Milk replacer fed calves had higher starter intake (milk replacer=0.22 vs. whole milk=0.19 kg day-1), but lower dry matter intake (0.61 vs. 0.67 kg day-1) and the lowest weight at weaning (49 vs. 59 kg). When milk replacer was started at 3 days, calves had higher starter intake (milk replacer at 3 days=0.25 vs. milk replacer at 15 days=0.20 kg day-1) and lower weight at weaning (47.3 vs. 51 kg) in relation to milk replacer starting at 15 days. Age at weaning and mortality rate were not affected by the probiotic supplementation or liquid diet.A possibilidade de proibição do uso de antibióticos como promotores de crescimento para animais de produção tem feito com que consumidores e produtores procurem por alternativas. Os probióticos têm se mostrado promissores em cumprir este papel e por esta razão, setenta e nove bezerros da raça Holandesa foram utilizados para avaliar a adição de probiótico constituído por Lactobacillus acidophilus, Enterococcus faecium e Saccharomyces cerevisiae ao aleitamento. Os animais foram distribuídos em um delineamento inteiramente casualizado, com arranjo fatorial de tratamentos 3x2, correspondendo ao tipo de dieta líquida (leite integral, sucedâneo ao 3° dia ou sucedâneo ao 15° dia de idade, com adição ou não de probiótico). O período experimental foi do nascimento até 15 dias após a desmama. O fornecimento de probiótico a bezerros(as) aleitados(as) com sucedâneo a partir dos 3 dias de idade melhorou o ganho de peso (com probiótico=0,22 vs. sem probiótico=0,16 kg dia-1) e conversão alimentar (2,62 vs. 3,85) até a desmama, e conversão alimentar (1,66 vs. 2,03) pós-desmama. Os bezerros aleitados com sucedâneo consumiram mais concentrado em relação aos que receberam leite integral (sucedâneo=0,22 vs. leite=0,19 kg dia-1), mas consumiram menos matéria seca total (0,61 vs. 0,67 kg dia-1) e apresentaram menor peso à desmama (49 vs. 59 kg). Quando o uso de sucedâneo foi iniciado aos 3 dias, os bezerros apresentaram maior consumo de concentrado (sucedâneo aos 3 dias=0,25 vs. sucedâneo aos 15 dias=0,20 kg dia-1) e menor peso à desmama (47,3 vs. 51 kg) em relação aos bezerros aleitados com sucedâneo aos 15 dias

Nutritional composition and fermentative characteristics of Massai grass silage added with licuri (Syagrus coronata) cake

This study evaluated the best level of inclusion of licuri cake (Syagrus coronata) in massai grass (Megathyrsus maximus) silage by chemical composition and fermentation quality of the silage. The experiment was conducted at Experimental Farm of the School of Veterinary Medicine and Animal Science of Federal University of Bahia. The treatments were composed by massai grass cut at 40 days, chopped and added at levels 0, 80, 160 and 240 g kg DM-1 of licuri cake. After mixing, the material was compressed in experimental silos, which were opened after 76 days. The experimental design was completely randomized, with four treatments and four replications. Data were analyzed by analysis of variance and regression. The addition of licuri cake improve linear increase (P < 0.01) in the contents of dry matter, crude protein, ether extract, total digestible nutrients, pH, NH3-N, dry matter intake, digestible dry matter and forage value index in massai grass silage There was a linear reduction in the contents of ash, neutral detergent fiber, acid detergent fiber, hemicellulose and cellulose (P < 0.01). There were no differences on contents non-fibrous carbohydrates (P = 0.356) and acid detergent lignin (P = 0.432). It is recommended the inclusion of licuri cake at level of 240 g kg DM-1 in massai silage, because provided the greatest chemical composition, dry matter intake, digestible dry matter and forage value index

Insulin-like growth factorI (IGF-I) in newborn calves fed colostrum of cows treated with rbst.

O presente trabalho teve por objetivo verificar o efeito de diferentes níveis de IGF-I no colostro de vacas que receberam rbST durante o período pré-parto, no desenvolvimento do trato intestinal e na expressão do gene do IGF-I e de seu receptor no fígado e intestino de bezerros. Quarenta e duas vacas da raça Holandesa, gestantes e multíparas foram distribuídas ao acaso em dois grupos de 21 animais, o grupo rbST que recebeu hormônio de crescimento (500 mg rbST) e o grupo controle que recebeu injeção de vitamina E. As aplicações tiveram início aos 35 dias pré-parto, em intervalos de 14 dias até a data de parição. Os bezerros recém-nascidos foram distribuídos aleatoriamente, de acordo com as seguintes idades em que foram abatidos: após o nascimento e sem a ingestão de colostro, dois e sete dias de vida com ingestão de colostro das respectivas mães. Após o abate, amostras do fígado e segmentos do intestino delgado (jejuno e íleo) foram coletadas para quantificação de DNA, RNA, proteína total e o RNAm do IGF-I e do receptor tipo I. O delineamento experimental utilizado foi o inteiramente casualizado, numa estrutura fatorial 2x3, correspondendo aos grupos das mães (rbST ou controle) e as idades dos bezerros (após o nascimento, dois e sete dias de vida). No fígado, as concentrações de RNA e proteína (mg/g tecido) foram maiores no segundo dia de vida e a relação proteína/RNA aumentou no sétimo dia de vida (P<0,05). O jejuno apresentou interações entre os tratamentos nas concentrações de DNA, proteína e relações proteína/RNA e RNA/DNA (P<0,05). Os bezerros que consumiram colostro proveniente de vacas que receberam rbST apresentaram, no jejuno, maiores concentrações de DNA no segundo dia de vida e diminuição a níveis intermediários entre nascimento e dois dias, comparados aos sete dias de vida. Este efeito também foi observado na relação proteína/RNA. No grupo controle, também se verificou aumento de DNA aos dois dias, mas não houve diferenças aos sete dias, e a relação proteína/RNA foi semelhante entre as idades. A concentração de proteína no jejuno do grupo rbST aumentou no segundo dia de vida e diminuiu no sétimo, enquanto que no grupo controle, este aumento foi verificado apenas no sétimo dia de vida. A relação RNA/DNA diminuiu apenas no grupo controle (P<0,05). A expressão do gene do IGF-I foi maior ao nascimento e aos sete dias de idade no fígado dos bezerros do grupo rbST (P<0,05). As concentrações do gene do receptor tipo I diminuíram com a idade dos bezerros (P<0,05). Ao nascimento, o intestino dos bezerros apresentou condição de resposta celular à presença do IGF-I proveniente do colostro. Os resultados sugerem que as células do jejuno de bezerros do grupo rbST apresentaram um diferente estágio de maturação.The objective of this study was to verify the effect of different levels of IGF-I in colostrum of cows treated with rbST during dry period, in the development of the intestinal tract and IGF-I and receptor gene expression in the liver and intestine of calves. Forty-two Holstein cows, in gestation and multiparous, were randomly assigned in two groups of 21 animals. Group rbST received injection of growth hormone (rbST), and group control received vitamin E injection. Both treatments started 35 days pre-partum, and were administered every 14 days until parturition. Newborn calves were randomly assigned to the following ages of slaughter: just after birth and without colostrum ingestion; two and seven days of life with colostrum ingestion from their respective mothers. After slaughter, samples from liver and small intestine (jejunum and ileum) were collected for quantification of DNA, RNA, total protein and mRNA of IGF-I and receptor type I. A completely randomized design was used with 2X3 factorial arrangements of treatments, which the factors were the mothers group (control and rbST) and age (just after birth, two and seven days of life). In the liver, RNA and protein concentrations (mg/g tissue) were higher in the second day of age and protein/RNA ratio increased in the seventh day (P<0.05). The jejunum showed interaction among the treatments in the concentrations of DNA and protein, and protein/RNA RNA/DNA ratios (P<0.05). Calves fed colostrum from mothers that received rbST presented, in jejunum, higher DNA concentration in the second day of life, and decrease to intermediate levels between birth and two days, compared to seven days of age. This effect was also observed in protein/RNA ratio. In the control group, it was also verified DNA increase at two days, but there was not difference in the seventh day, and protein/RNA ratio was similar among ages. Protein concentration in jejunum of rbST group increased in the second day and decreased in the seventh, but in the control group, this increase was verified only in the seventh day of age. RNA/DNA ratio decreased in the control group (P<0.05). Expression of IGF-I was higher at birth and seven days old in the liver of the calves from rbST group (P<0.05). The concentrations of receptor type I mRNA decreased with calves age (P<0.05). At birth, the small intestine of calves showed a condition of cellular response to the presence of IGF-I in colostrum. These results suggest that cells in jejunum of calves from rbST group presented a different phase of maturation