ABSTRACT. Four strains of Staphylococcus aureus isolated from cows with mastitis were assessed as to in vitro sensitivity to four commercial disinfectants (chlorine, polvidone-iodine, chlorhexidine, and lactic acid) used in teat pre- and post-dipping, in the presence and absence of organic matter. The concentration of the disinfectants was determined in accordance with the Brazilian Pharmacopoeia. Four isolates identified as S. aureus from cows diagnosed with subclinical mastitis were subjected to susceptibility testing against disinfectants through an absorbance evaluation at 600 nm on a spectrophotometer. Exposure times (15”, 30”, 60” and 90”) were clocked, and streaking was performed in Brain Heart Infusion (BHI) medium. The iodine sample presented a lower concentration (1.9%) than that given by the manufacturer (2.5%). There was greater (p < 0.05) in vitro disinfectant activity for chlorhexidine and chlorine, with and without organic matter. However, inhibition by organic matter occurred more intensely in the iodine disinfectant (99.0%). The inhibition percentage of S. aureus against iodine and lactic acid at 15, 30, 60 and 90 s was numerically lower than against chlorhexidine and chlorine, regardless of organic matter. Therefore, chlorhexidine and chlorine have greater inhibitory activity against S. aureus, both with and without organic matter. ABSTRACT (chlorine polvidoneiodine, polvidoneiodine polvidone iodine, polvidone-iodine pre postdipping, postdipping post dipping, dipping post-dipping Pharmacopoeia S spectrophotometer 15 , (15” 30 30” 90” clocked BHI (BHI medium 1.9% 19 1 9 (1.9% 2.5%. 25 2.5% . 2 5 (2.5%) p 0.05 005 0 05 However 99.0%. 990 99.0% 99 (99.0%) 6 Therefore (15 3 1.9 (1.9 2.5 (2.5% 0.0 00 99.0 (99.0% (1 1. (1. 2. (2.5 0. 99. (99.0 ( (2. (99. (2 (99 (9

RESUMO: Este trabalho foi desenvolvido com o objetivo de investigar a associação da composição proteica do leite com o tamanho das micelas de caseína, e o efeito do TMCN sobre a firmeza do coágulo enzimático e da produção de massa seca do coágulo produzido em escala reduzida. Foram coletadas 140 amostras de leite cru de diferentes fazendas. Os dados foram analisados usando dois modelos lineares, incluindo somente efeitos fixos. Menores micelas de caseína foram associadas com maior conteúdo de k-caseína e menor conteúdo de αs-caseína. O tamanho das micelas de caseína sem o efeito da αs-caseína e k-caseína não apresentou efeito sobre a firmeza do coágulo, porém apresentou efeito significatico sobre a produção de massa seca do coágulo. Esses resultados demonstram a importância do tamanho das micelas de caseína para otimizar a produção de queijo.

ABSTRACT: The aim of the present study was to explore the association between milk protein content and casein micelle size and to examine the effects of casein micelle size on enzymatic curd strength and dry matter curd yield using reduced laboratory-scale cheese production. In this research, 140 bulk tank milk samples were collected at dairy farms. The traits were analyzed using two linear models, including only fixed effects. Smaller micelles were associated with higher κ-casein and lower αs-casein contents. The casein micellar size (in the absence of the αs-casein and κ-casein effects) did not affect the enzymatic curd strength; however, smaller casein micelles combined with higher fat, lactose, casein and κ-casein contents exhibited a favorable effect on the dry matter curd yield. Overall, results of the present study provide new insights into the importance of casein micelle size for optimizing cheese production.

Antiretroviral therapy has been associated with side effects, either from the drug itself or in conjunction with the effects of human immunodeficiency virus infection. Here, we evaluated the side effects of the protease inhibitor (PI) indinavir in hamsters consuming a normal or high-fat diet. Indinavir treatment increased the hamster death rate and resulted in an increase in triglyceride, cholesterol and glucose serum levels and a reduction in anti-oxLDL auto-antibodies. The treatment led to histopathological alterations of the kidney and the heart. These results suggest that hamsters are an interesting model for the study of the side effects of antiretroviral drugs, such as PIs.

O presente trabalho teve como objetivo investigar a influência do estágio da lactação sobre as características físico-químicas e a celularidade do leite em ovelhas da raça Santa Inês. Desse modo, 143 amostras de leite negativas no exame bacteriológico e sem alterações na prova da caneca de fundo escuro provenientes de 33 ovelhas Santa Inês foram utilizadas para determinar a contagem automática e microscópica de células somáticas, os teores de extrato seco total, gordura, lactose e proteína. Os resultados do presente estudo apontaram para aumento da celularidade do leite e dos teores de gordura e proteína e redução do teor de lactose no final da lactação, embora não tenham sido observadas alterações no extrato seco total no leite desses animais durante a lactação. O presente estudo apontou ainda para correlação significativa entre a contagem automática e a microscópica de células somáticas (r = 0,80), a porcentagem de leucócitos mononucleares (r = -0,45), a porcentagem de leucócitos polimorfonucleares (r = 0,45), os teores de lactose (r = - 0,44), proteína (r = 0,37) e gordura (r = 0,30). No entanto, não se observou correlação significativa entre a CCS automática e o teor de extrato seco total (r = 0,007).

The purpose of the present trial was to investigate the influence of lactation stage on milk cellularity and physicochemical characteristics. Thus, 143 milk samples from 33 Santa Ines ewes negative in the bacteriological examination and without any alteration in the strip cup test were used to determine the automatic and microscopic somatic cell count (SCC), and the fat, lactose, protein and total solids content. The results of the present study showed an augment in the SCC and in the fat and protein content, besides a reduction in lactose content at the last lactation stage. Otherwise, no alteration was observed in the total solids content during the lactation period. This study pointed out to a significant correlation between the automatic SCC and the microscopic SCC (r = 0.80), percentage of polymorphonuclear leukocytes (r = 0.45), percentage of mononuclear leukocytes (r = -0.45), lactose (r = - 0.44), protein (r = 0.37) and fat (r = 0.30) content. Nevertheless, significant correlation between the automatic SCC and the total solids content was not observed.

O objetivo do presente estudo foi avaliar a capacidade de liberação de peróxido de hidrogênio (H2O2) por fagócitos oriundos de glândulas mamárias bovinas sadias e infectadas. Desse modo, 73 amostras de leite provenientes das glândulas mamárias foram classificadas em sadias e infectadas de acordo com a cultura bacteriológica e a contagem de células somáticas (CCS). Após o isolamento das células do leite, procedeu-se à contagem diferencial de leucócitos e determinação da liberação de H2O2 pela oxidação da solução de vermelho fenol. Foi observada menor liberação de H2O2 pelos fagócitos oriundos dos quartos mamários infectados, assim como houve correlação negativa entre a liberação de H2O2 por fagócitos e a CCS (r=-0,34; P=0,0025), e a porcentagem de neutrófilos (r=-0,24; P=0,04). Além disso, houve tendência de menor liberação de H2O2 pelos fagócitos estimulados por forbol 12-miristato 13-acetato nas glândulas mamárias infectadas. Entretanto, observou-se maior liberação de H2O2 pelos fagócitos em 1mL de leite nos quartos mamários infectados, ao considerar a CCS mL-1. Pode-se concluir que fagócitos de quartos mamários infectados apresentaram menor liberação de H2O2, o que indica menor capacidade microbicida. Por outro lado, observou-se maior liberação de H2O2 pelos fagócitos em 1mL de leite nos quartos infectados, fato que pode contribuir com o maior recrutamento de leucócitos para a glândula mamária e/ou a persistência do processo inflamatório.

The purpose of the present study was to evaluate the hydrogen peroxide (H2O2) release by phagocytes from infected and uninfected mammary glands in dairy cows. Thus, milk samples from 73 quarters were divided in healthy and infected samples according to bacteriological culture and somatic cell count (SCC). After separation of milk cells, the samples were submitted to differential SCC and hydrogen peroxide release by oxidation of phenol red. There was a lower H2O2 release by phagocytes from infected quarters, as well as, a negative correlation between the H2O2 release by phagocytes and SCC (r=-0.34; P=0.0025) and percentage of neutrophils (r=-0.24; P=0.04). Furthermore, it was observed a tendency toward a lower H2O2 release by phagocytes stimulated by phorbol 12-myristate 13-acetate in the infected quarters. However, a higher H2O2 release by phagocytes was observed in milk samples from infected quarters by the estimation of the H2O2 release by phagocytes in 1mL of milk according to SCC mL-1 of each sample. The present study showed a decrease in H2O2 release by the infected quarters which indicate lower microbicidal activity. However, the higher H2O2 release by phagocytes in 1mL of milk in the infected quarters may contribute to recruitment of leukocytes to the site of infection and the persistence of infection.

Para avaliar a influência da suplementação com selênio e vitamina E sobre o perfil proteico e metabolismo oxidativo de cordeiros infectados experimentalmente pelo Haemonchus contortus, trinta cordeiros fêmeas foram distribuídos em quatro grupos: G1 (n=10): animais infectados; G2 (n=10): infectados e suplementados; G3 (n=5): controle; e G4 (n=5): não infectados e suplementados. Os grupos 1 e 2 receberam 500 larvas de H. contortus (L3), via oral, por um período de 20 dias, com intervalo de dois dias entre as doses. A suplementação nos grupos 2 e 4 foi realizada no dia zero, com 0,1mg kg-1 de Selenito de sódio (1,67%) e com 2.000UI de vitamina E por via intramuscular (IM). Somente a vitamina E foi reaplicada no dia 30. As coletas de sangue para determinação do perfil proteico (proteína total, albumina, alfa, beta e gamaglobulina) e metabolismo oxidativo (espécies reativas ao ácido tiobarbitúrico-TBARS e a enzima glutationa peroxidase (GSPX) foram realizadas nos dias zero, 20, 30, 45, 60 e 80. OPG foi quantificado nos dias 0, 20 ,45 e 80. Em relação aos valores de proteínas totais, albumina, betaglobulina e gamaglobulina, as principais diferenças foram observadas quando os grupos parasitados foram comparados com o grupo somente suplementado; e este manteve valores mais elevados. Conclui-se que não há influência da suplementação com selênio e vitamina E no perfil proteico e metabolismo oxidativo quando os cordeiros se encontram severamente parasitados por H.contortus.

The objective of the present study was to describe the influence of supplementation with selenium and vitamin E on the protein and oxidative profiles of lambs experimentally infected with Haemonchus contortus. Thirty female lambs were divided into four groups as follows: G1 (n=10): infected animals; G2 (n=10): infected and supplemented; G3 (n=5): control; G4 (n=5): non-infected and supplemented. Groups 1 and 2 received 500 H. contortus larvae (L3) orally for a period of 20 days, with 2-day intervals between doses. Supplementation in groups 2 and 4 was performed on day zero by injecting 0.1mg kg-1 of sodium selenite solution (1.67%) and 2,000IU vitamin E through the intramuscular (IM) route. Vitamin E alone was injected once again on day thirty. The blood samples to determine the protein profile (total protein, albumin, alpha, beta and gamma) and oxidative metabolism (species reactive to thiobarbituric acid and glutathione peroxidase (GSPX) were performed on days zero, 20, 30, 45, 60 and 80. The OPG was quantified on days 0, 20, 45 and 80. Regarding the values of total proteins, albumin, beta and gamma globulins, the main differences were observed when the parasitized groups were compared to the supplemented, non-infected group, the latter exhibiting higher values. It is concluded that there is no influence of supplementation with vitamin E and selenium in the protein profile and oxidative metabolism when the lambs are severely parasitized with H. contortus.