Raquel Fraga e Silva Raimondo

Proteínas do soro lácteo de vacas da raça Jersey durante a lactação

To evaluate the whey proteins during the lactation, whey obtained from 48 milk samples collected from 12 Jersey cows before milking were studied. Cows were distributed into three groups as follows: early (30-120 days), middle (121-210 days) and end of lactation (more than 211 days). The proteinogram consisted of total proteins concentration determined by biuret method and polyacrymalide gel electrophoresis (SDS-PAGE). A gradual and significant decrease of some fractions of the whey was observed during the lactation cycle albumin, lactoferrin, immunoglobulins, β-lactoglobulin and α -lactoalbumin. The normal ranges obtained for the whey proteins of Jersey cows were: whey total proteins 569.0 to 713.0mg/dL, lactoferrin 36.0 to 49.0mg/dL, albumin 24.0 to 34.0mg/dL, immunoglobulins heavy chain 38.0 and 51.0mg/dL; immunoglobulins light chain 59.0 to 95.0mg/dL, β-lactoglobulin 207.0 to 256.0mg/dL, α-lactoalbumin 117.0 to 157.0mg/dL; protein with 226 KDa 5.80 to 12.0mg/dL, and protein with 118 KDa 2.30 to 6.80mg/dL.

Avaliação do número de células somáticas do leite de bovinos da raça Jersey durante o primeiro mês de lactação

Com a finalidade de estabelecer os valores de referencia da contagem de celulas somaticas do leite de bovinos da raca Jersey, criados no Estado de Sao Paulo, durante o primeiro mes de lactacao, bem como avaliar a influencia da fase colostral, examinaram-se 418 amostras de leite, provenientes de quartos mamarios sadios e sem crescimento bacteriano. O leite foi colhido assepticamente antes da ordenha e a contagem de celulas somaticas foi determinada por citometria de fluxo e pelo Teste do CMT. Demonstrou-se a significativa influencia do primeiro mes de da lactacao sobre a contagem de celulas. Verificou-se que a transicao da secrecao de colostro para leite em relacao ao numero de celulas somaticas esta finalizado a partir do 15o dia de lactacao, sendo recomendado a adocao dos seguintes valores de referencia: no colostro, obtidos nas primeiras 24 horas de lactacao entre 472.405 e 2.003.921 celulas/ml, no periodo compreendido do 2o ao 15o dia de lactacao valores entre 103.920 e 1.298.361 celulas/ml e a partir do 15o dia de lactacao entre 37.714 e 205.549 celulas/ml.

Influência da gestação e do puerpério no lipidograma de bovinos da raça Holandesa

ABSTRACT In order to establish the influence of gestation and puerperium on the lipid profile of Holstein cattle, the concentrations of cholesterol, triglycerides, nonesterified fatty acids (NEFA), β -hydroxibutyrate ( β -HBO), and glucose were determined in samples of serum and plasma from 80 animals distributed into five experimental groups (G): G1 – 16 non pregnant females; G2 – 18 females in the initial phase of gestation, up to three months; G3 – 15 pregnant females, with gestation from three to six months; G4 – 15 females in the last stage of gestation, from six to nine months; G5 – 16 females soon after delivering, up to 30 days in puerperium. The lipid profile of healthy Holstein cows was influenced by gestation. The concentration of NEFA was higher in the last trimester of gestation while the serum concentration of β -HBO was higher in the first trimester of gestation. In the first 30 days after delivering, the concentrations of NEFA and β -HBO were higher, while those of triglycerides were lower when compared to those of cows during gestation. Keywords: bovine, lipid profile, gestation, Holstein

Teores de cloretos, lactose e índice cloretos/lactose na secreção láctea de bovinos da raça Jersey no primeiro mês da lactação

In order to assess the influence of the colostral period on chloride and lactose levels and on the chloride/lactose ratio, 419 milk samples from 127 Jersey cows were analyzed. The samples were collected from healthy udders that did not present any bacterial growth in the microbiological examination. Cows were distributed into eight groups as follows: 0 ┤1/2 day; 1/2 ┤1 day; 1 ┤2 days; 2 ┤3 days; 3 ┤5 days; 5 ┤7 days; 7 ┤15 days; 15 ┤30 days of lactation. The samples were collected before milking to analyze the levels of chloride by colorimetric titration, lactose by infrared radiation, and to determine the chloride/lactose ratio. In the first 24 hours after partition, there was an abrupt reduction in chloride levels as well in chloride/ lactose ratio, associated with an increase in lactose levels. It was observed that the transition of the secretion from colostrum to milk, regarding chloride and lactose levels and chloride/lactose ratio occurred during the first week of lactation: from the 3rd day of lactation for chloride and chloride/lactose ratio and from 4th for the lactose levels. It is recommended the use the following thresholds as normal ranges for the first 24 hours of lactation: chloride 3.94g/dL, and chloride/lactose ratio 4.03g/dL and chloride/lactose ratio <3.54.