ABSTRACT The objective of this study was to evaluate passive immunity transfer, health, performance, and metabolism of Holstein calves fed colostrum supplement associated with medium-quality colostrum. After birth, calves were blocked according to birth weight and date and distributed into the following treatments: high-quality colostrum (> 50 mg of Ig/mL; n = 15; 150 g kg−1 BW; positive control group); medium-quality colostrum (30-40 mg of Ig/mL; n = 14; 150 g kg−1 BW), and medium-quality colostrum (30-40 mg of Ig/mL; n = 15; 150 g kg−1 BW) + colostrum supplement (15 mL) given with the colostrum. Colostrum was given within the first 12 h of life in two meals by nipple bottle, and colostrum replacer was administered by a blister syringe. Blood samples were taken every 12 h up to 48 h of life for total serum protein (TSP) evaluation. After colostrum feeding, calves were fed 4 L of transition milking, split in two meals for a period of one to four days and received milk replacer thereafter. Calves were individually housed, with free access to water and concentrate and bucket-fed 6 L/d of milk replacer up to the sixth week of life, when they received 4 L/d until weaning, with eight weeks. Colostrum feeding protocol affected the TSP concentration in the first 48 h of life, while the concentrations of albumin, glucose, β-hydroxybutyrate, γ-glutamyl transferase, and alkaline phosphatase were not affected. During the milk-feeding period, the concentrate and total dry matter intake were not affected by the colostrum protocol, but increased as animals aged. Colostrum-feeding protocol did not affect performance or health of calves. Feeding colostrum supplement associated with medium-quality colostrum had no effect on passive immune transfer, performance, nor on the metabolism during the liquid-feeding phase.

RESUMO: O objetivo desse estudo foi o de avaliar os sinais clínicos, análise de gases e os efeitos metabólicos da diarreia em bezerros em aleitamento, consumindo concentrado inicial contendo polpa cítrica (PC) como substituto de milho. Vinte e quatro bezerros recém-nascidos da raça Holandesa foram distribuídos, de acordo com a composição do concentrado, nos seguintes tratamentos: (1) 0% PC, (2) 32% PC, (3) 64% PC, na matéria seca. Os bezerros foram alojados em abrigos individuais, com acesso livre a água e concentrado, e receberam 4L/d de sucedâneo lácteo. Após o diagnóstico de diarreia, avaliações de escore fecal, sinais clínicos e medidas de parâmetros fisiológicos foram realizadas três vezes ao dia durante 3-d. Amostras de sangue foram colhidas para análise de eletrólitos, hemogasometria e metabólitos plasmáticos. A composição do concentrado não afetou o escore fecal, as características das fezes diarreicas, ou o agravamento dos sinais clínicos da diarreia (P>0,05). Alterações nos parâmetros plasmáticos, de hemogasometria ou de eletrólitos, em função da composição do concentrado, não resultaram em desidratação, acidose ou outro distúrbio metabólico nos bezerros diarreicos (P>0,05). As concentrações de lactato total e D-lactato foram superiores para bezerros alimentados com concentrado sem inclusão de polpa ou com 64% de inclusão, enquanto a concentração de L-lactato foi superior somente para aqueles consumindo concentrado com 64% de PC. No entanto, os bezerros não apresentaram sinais de acidose metabólica. Os índices de conforto térmico influenciaram os parâmetros clínicos e fisiológicos (P<0,05). A polpa cítrica pode substituir o milho na composição de concentrados para bezerros sem prejudicar a saúde intestinal ou o metabolismo de bezerros jovens acometidos por diarreia.

ABSTRACT: The objective of this study was to evaluate clinical signs, gas analysis, and metabolic effects of diarrhea in milk-fed calves consuming starter feed containing citrus pulp (CP) as a replacement for corn. Twenty-four newborn Holstein male calves were distributed into treatments according to starter composition: (1) 0% CP, (2) 32% CP, (3) 64% CP, on dry matter basis. The calves were housed in individual hutches, with free access to water and concentrate, and received 4 L/d of milk replacer. After diarrhea diagnosis, evaluations of fecal score, score of clinical signs and measurement of physiological parameters were performed three times a day during 3-d. Blood samples were collected for electrolytes, blood gases, and plasma biochemical analysis. Starter feed composition had no negative effect (P>0.05) on fecal score, characteristics of diarrheic stools and on the aggravation of diarrhea clinical signs. Biochemical, blood gases and electrolytes changes, as a function of starter composition, did not resulted (P>0.05) in dehydration, acidosis, or other metabolic disturbance animals. Total lactate and D-lactate plasma concentrations were higher for calves on control and 64% CP, and L-lactate was highest for the 64% CP; however, calves showed no signs of metabolic acidosis. Thermal comfort indexes influenced clinical and physiological parameters (P<0.05). Citrus pulp may replace corn in starter composition without prejudice to intestinal health or metabolism of young diarrheic calves.

RESUMO Vinte bezerros mestiços da raça Holandês x Jersey, distribuídos em blocos completos casualizados, foram utilizados para determinar o efeito do fornecimento de probiótico de bactérias ruminais sobre o desempenho e os parâmetros sanguíneos de bezerros leiteiros em sistema de desaleitamento precoce. Os animais foram submetidos ao tratamento controle ou ao fornecimento via oral de 2g de probiótico/dia durante o aleitamento. Os bezerros receberam 6 litros de sucedâneo lácteo por dia divididos em duas refeições diárias e foram desaleitados de forma gradual na 6ª semana de vida, entretanto, as variáveis foram coletadas até a 10ª semana. O consumo de concentrado inicial e o escore fecal foram registrados diariamente. Semanalmente foram realizadas pesagens e medidas corporais como, altura de cernelha, largura de garupa e perímetro torácico. Foram realizadas colheitas de sangue nas semanas, 2, 4, 6, 8 e 10, 2h após o primeiro aleitamento, para determinação de concentrações plasmáticas de glicose, proteína total, albumina, β-hidroxibutirato e cortisol. A suplementação de probiótico não afetou o consumo de concentrado, o peso, o ganho de peso, e as medidas corporais dos animais. Não houve efeito sobre o escore fecal entre os tratamentos. Os parâmetros sanguíneos não foram alterados em resposta ao fornecimento do probiótico, apenas a concentração de cortisol, que foi maior nos animais suplementados. O fornecimento de probiótico de bactérias ruminais não favorece o desempenho e o metabolismo de bezerros leiteiros em sistema de desaleitamento precoce.

SUMMARY Twenty crossbred Holstein x Jersey calves, distributed in a completely randomized block design were used to evaluate the effect of probiotic of ruminal bacteria supply on performance and blood parameters of dairy calves in early weaning system. Animals were submitted to control treatment or supplementation of 2g/ day of probiotic via milk replacer. The calves received 6 liters of milk replacer per day divided in two daily meals and were gradually early weaned at the 6th week of age, however, all data were collected until 10th week of age. Starter feed intake and fecal score were registered daily. Weekly, body weight, and body measures like, height withers, hip width and heart girth were taken. Blood samples were taken at the 2nd, 4th, 6th, 8th and 10th week, two hours after the morning feeding, to determine plasma concentrations of glucose, total protein, albumin, β-hydroxybutyrate and cortisol. Probiotic supplementation didn´t affect starter feed intake, daily weight gain, weight or body measurements. The probiotic supply also had no effect on fecal scores between treatments. Blood parameters were not affect by probiotic supplementation. The probiotic of ruminal bacteria supply present no benefits on the performance or metabolism of dairy calves in early weaning system.