O presente trabalho teve como objetivo a análise microbiológica das amostras de leite de fêmeas bubalinas, a avaliação da quantidade de UFC/mL dos microrganismos isolados e a contagem de células somáticas/mL. Os quartos mamários foram submetidos ao teste de tamis e CMT e foram colhidas 262 amostras de leite de fêmeas bubalinas primíparas e pluríparas; para análise microbiológica, quantificação das UFC/mL e contagem de células somáticas/mL. A contagem das células somáticas foi realizada através da leitura em microscopia ótica dos esfregaços de leite. A leitura foi realizada utilizando-se a totalidade dos campos existentes no esfregaço de 1cm2. No teste do tamis, 99,6% das amostras apresentaram resultado negativo. No CMT, observamos resultado negativo em 88,2% das amostras; traços (8%), positivo 1+ (1,5%); positivo 2+ (1,15%); positivo 3+ (1,15%). A análise microbiológica apresentou amostras sem crescimento de microrganismos (75,6%); isolamento de Staphylococcus spp. (11,8%); Corynebacterium spp. (7,3%); Streptococcus spp, (3,1%) e crescimento de microrganismos associados (1,2%). A contagem total de células somáticas das amostras avaliadas apresentou mediana de 2300 células/mL de leite; a mediana da contagem de PMN e MN foi, respectivamente, 700 células/mL e 1500 células/ml de leite, com diferença estatisticamente significante (P<0,0001). As quantidades totais de células somáticas/mL e as quantidades de células polimorfonucleares e mononucleares nas amostras negativas ao exame microbiológico foram estatisticamente menores do que nas amostras que apresentaram isolamento de microrganismos. A mediana relativa às quantidade de UFC/mL foi de 550 UFC/mL para as amostras com isolamento de Corynebacterium spp.; 500 UFC/mL para as amostras com isolamento de Staphylococcus spp e 1100 UFC/mL para Streptococcus spp. ,sendo que não houve diferença estatisticamente significativa entre eles. Concluiu-se que a espécie bubalina, apresenta baixos índices de mastite; nas amostras com isolamento de microrganismos, o número de UFC/mL é pequeno.Existe um número de animais que apresenta resultado positivo no exame microbiológico do leite, sem contudo apresentar sinais de processo inflamatório. / The aim of the present study was the microbiological analysis of milk samples from female buffaloes, the amount evaluation of CFU/mL of the isolated microorganisms and the somatic cells counting/mL. The mammary quarters were submitted to strip cup test and CMT and 262 milk samples were colletected from buffalo cows to microbiological analysis, CFU/mL quantification and somatic cells counting. The somatic cells countings were obtained through optical microscopy reading of the milk smears, where all fields of the 1 cm2 smears area were considered. In the strip cup test, 99,6% of the samples had negative results. In the CMT, the negative results were observed in 88,2% of the samples; traces (8%), 1+ positive (1,5%), 2+ positive (1,15%) and 3+ positive (1,15%). The microbiological analysis resulted in samples with no microorganism growth (75,6%); Staphylococcus spp (11,8%); Corynebacterium spp (7,3%) and Streptococcus spp (3,1%) and associated microorganisms growth (1,15%). The total counting of somatic cells in the evaluated milk samples showed median of 2300 cells/mL; while PMN and MN counting median were 700 cells/mL and 1500 cells/mL respectivelly, with a significant statisticall difference (P< 0,0001). The total somatic cells counting/mL and the amount of PMN and MN cells in the microbiological negative samples were statistically smaller than the findings in the samples that showed microorganism isolation. Concerning the amount of CFU/mL, the median obtained for samples with Corynebacterium spp was 550CFU/mL; 500 CFU/mL for Staphylococcus spp samples and 1100 CFU/mL for Streptococcus spp results, with no statiscally significant difference between them. It follows that he buffalo species has a low rate of mastitis; the number of CFU/mL is small in the microbiological positive samples. There are a number of animals that despite presenting milk microbiological exam with positive results, showed no signs of inflamatory process.

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-05-09T15:36:26Z No. of bitstreams: 1 Ney Braulio de Oliveira Lins.pdf: 535128 bytes, checksum: bf7b656b16605ec0590fcb36feaac735 (MD5) / Made available in DSpace on 2017-05-09T15:36:26Z (GMT). No. of bitstreams: 1 Ney Braulio de Oliveira Lins.pdf: 535128 bytes, checksum: bf7b656b16605ec0590fcb36feaac735 (MD5) Previous issue date: 2013-07-01 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / High somatic cell counts and high bacteria counts are related to health problems of the mammary gland and milking hygiene, what can bring harm to the industry, as well as to public health. The lactoperoxidase system acts directly on the mammary gland health generating hypothiocyanate ions, a bactericidal compound, wich concentrations depend, among other factors, on the presence of plants in the diet rich in cyanogenic glycosides. The objective of this study was to evaluate the quality of the milk in lactating Saanen goats fed maniçoba hay. Seven Saanen goats were used, with 39 ± 2,9 days of lactation and body weight 43,3 ± 7,6 kg in an statistical Latin square design 4 x 4. The treatments consisted of the replacement of the Tifton hay by maniçoba hay (0; 33,3; 66,7 and 100%). The concentrations of thiocyanate ions, fat, protein, lactose, total solids and dry extract in milk were not affected (P <0,05) neither by the substitution of tifton hay for maniçoba nor by the preservative. The SCC was lower (P <0,05) in samples without preservative and was quadratic affected of (P<0,0001) by the substitution of tifton hay for maniçoba. The total bacteria count increased significantly in milk samples without preservative, but was not affected by the substitution of tifton hay for the maniçoba hay. / Altas contagens de células somáticas e altas contagens bacterianas estão relacionadas com problemas de saúde da glândula mamária e de higiene na ordenha, e podem trazer prejuízos para indústria, assim como para a saúde pública. O sistema lactoperoxidase atua diretamente sobre a saúde da glândula mamária gerando íons hipotiocianato, composto de ação bactericida, cujas concentrações dependem, entre outros fatores, da presença na dieta de plantas ricas em glicosídeos cianogênicos. Objetiva-se com o presente trabalho avaliar a qualidade do leite de cabras Saanen em lactação alimentadas com feno de maniçoba. Foram utilizadas sete cabras Saanen, com 39 ± 2,9 dias de lactação e peso corporal médio de 43,3 ± 7,6 kg em um delineamento estatístico quadrado latino 4 x 4. Os tratamentos consistiram da substituição do feno do capim tífton por feno de maniçoba (0; 33,3; 66,7 e 100%). As concentrações de íons tiocianato, gordura, proteína, lactose, sólidos totais e extrato desengordurado no leite não foram influenciadas (P < 0,05) pela substituição do feno de tifton por feno de maniçoba nem pelo conservante. A CCS foi menor (P < 0,05) nas amostras sem conservante e foi influenciada de forma quadrática (P < 0,0001) pela substituição do feno de tifton por feno de maniçoba. A contagem de bactérias totais aumentou significativamente nas amostras de leite sem conservante, mas não foi influenciada pela substituição do feno de tifton por feno de maniçoba.

Orientador: Mirna Lucia Gigante / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-05T21:58:25Z (GMT). No. of bitstreams: 1 Vianna_PriscilaCristinaBizam_M.pdf: 410652 bytes, checksum: 9d1612b0e59cf63db41597cf8e7553e2 (MD5) Previous issue date: 2006 / Resumo: A mastite é uma reação inflamatória da glândula mamária, causada por bactérias patogênicas, que resulta no aumento da contagem de células somáticas (CCS) no leite. O leite com CCS alta apresenta alterações na composição, influenciando, portanto, na qualidade dos produtos lácteos processados. O objetivo deste trabalho foi avaliar o efeito da CCS do leite sobre o desenvolvimento da microbiota e características sensoriais do queijo Prato, durante a maturação. Para tanto, dois grupos de animais foram selecionados para a obtenção de leite com CCS baixa (< 200.000 cél/ml) e alta (> 700.000 cél/ml) e após a fabricação, os queijos foram avaliados quanto à composição centesimal. Após 6, 12, 19, 35 e 54 dias de armazenamento, foram avaliados quanto às contagens de bactérias lácticas, psicrotróficos, contagem total de bactérias e bolores e leveduras. O delineamento experimental utilizado foi do tipo fatorial 2 x 5 em blocos completamente aleatorizados. O efeito da CCS (2 níveis de variação) e do tempo de armazenamento (5 níveis de variação) sobre as variáveis estudadas foi avaliado por ANOVA aplicando-se teste de Tukey para comparação entre as médias ao nível de 5% de significância. A avaliação sensorial dos queijos foi feita através dos atributos firmeza, sabor e gosto residual amargo, utilizando-se a escala do ideal de nove pontos, e aceitação geral, através de escala hedônica de nove pontos, após 7, 21, 34, 48 e 61 dias de armazenamento. O leite de CCS alta apresentou pH significativamente maior que o leite de CCS baixa. Os queijos obtidos com leite de CCS alta apresentaram maior umidade que os de CCS baixa. A CCS afetou as contagens de bactérias lácticas e psicrotróficos, que foram maiores para os queijos com CCS baixa. A contagem total de bactérias, a contagem de bactérias lácticas e de psicrotróficos diminuíram durante o armazenamento, enquanto a contagem de bolores e leveduras aumentou independentemente da CCS. A avaliação sensorial indicou que os queijos de CCS alta apresentaram menor aceitação geral quando comparados aos queijos de CCS baixa / Abstract: Mastitis is an inflammatory reaction of the mammary gland, caused by pathogenic bacteria, resulting in increased number of somatic cells of milk. Milks with high somatic cells count (SCC) present alterations in the composition, influencing, therefore, the quality of processed dairy products. The objective of this work was to evaluate the effect of milk SCC on the development of microorganisms and sensorial characteristics, during ripening of Prato cheese. Two groups of animals were selected to obtain milk with low (< 200.000 cell/ml) and high (> 700.000 cell/ml) SCC. Centesimal composition of cheeses was evaluated after processing and after 6, 12, 19, 35 e 54 days of storage for lactic bacteria, psychrotrophs, total bacteria count, yeasts and moulds counts. A factorial arrangment of treatments 2 x 5 in a completely randomized blocks was used. The effect of SCC (2 levels of variation) and storage time (5 levels of variation) on studied variables was evaluated by ANOVA and Tukey¿s test at 5% of significance. The cheeses sensory evaluation was carried out through firmness, flavor and of lavors using ideal scale of nine points and general acceptance was evaluated by hedonic scale of nine points. The sensory evaluations were carried out after 7, 21, 34, 48 and 61 days of storage. Milk with high SCC had higher pH than milk with low SCC. Cheeses obtained from high SCC milk showed higher moisture than cheeses with low SCC. SCC affected lactic bacteria and psychrotrophs counts, as higher levels were found in low SCC cheeses. Total count bacteria, lactic acid and psychrotrophs counts decreased during storage, while yeasts and moulds count increased, independently of milk SCC. The sensory evaluation showed lower general acceptance to high SCC cheeses when compared with low SCC cheeses / Mestrado / Mestre em Tecnologia de Alimentos

Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-08-07T14:17:51Z No. of bitstreams: 0 / Made available in DSpace on 2015-08-07T14:17:51Z (GMT). No. of bitstreams: 0 / O câncer diferenciado da tireoide (CDT) representa cerca de 90% das malignidades tireoidianas com incidência crescente nas últimas décadas. As modalidades de tratamento incluem tireoidectomia, terapia com 131I (com e sem r-hTSH), radio e quimioterapias. Pouco se sabe sobre os efeitos desses tratamentos em nível celular. O presente trabalho foi proposto com o intuito de avaliar em que extensão a terapia com radioiodo pode causar danos em linfócitos periféricos de pacientes com CDT precedidos ou não com r-hTSH, levando-se em consideração, efeitos agudos, tardios e dosimétricos do 131I (estudo in vivo). Um estudo in vitro também foi realizado em células-alvo de tumores tireoidianos (WRO) por meio de análise de citotoxicidade, genotoxicidade e captação do radioiodo. Para tanto, amostras sanguíneas de pacientes, divididos em 2 grupos (grupo A com r-hTSH + 131I e grupo B somente com 131I) foram coletadas antes, 24h, 1 semana, 1 mês e 1 ano após administração do 131I para análise de aberrações cromossômicas (AC). Curva dose-resposta para 131I in vitro foi elaborada para a estimativa de dose absorvida nos pacientes, comparando as frequências de dicêntricos obtidas in vitro com dados in vivo pelo programa Monte Carlo. A iodoterapia induziu um aumento no número de AC em linfócitos de pacientes com valor máximo 24h após o tratamento, com declínio gradativo ao longo do tempo, com mais danos cromossômicos no grupo B em relação ao grupo A, atingindo níveis similares aos basais 1 anos após a administração do radioido. A frequência de dicêntricos encontrada nos linfócitos de pacientes 24h após o tratamento foi equivalente àquela induzida in vitro (0,354 ± 0,153 MBq/mL para o grupo A e 0,309 ± 0,154 MBq/mL para o grupo B), que corresponde a dose absorvida de 0,8 ± 0,3 Gy e 0,7 ± 0,3 Gy para os grupos A e B, respectivamente, sem significância estatística entre os grupos. As células WRO mostraram um ciclo celular relativamente lento de 96,3h com um cariótipo instável. O ensaio genotóxico mostrou uma radiorresistência relativamente alta (0,07 a 3,70 MBq/mL), sem significância estatística com e sem r-hTSH. No entanto, o ensaio citotóxico, mostrou uma tendência à queda nas concentrações mais altas de 1,85 (p<0,05) e 3,70 MBq/mL (p<0,01) somente na presença de r-hTSH, coincidindo com nível mais alto de captação. Células WRO foram relativamente radiorresitentes também à irradiação externa de 60Co na faixa de dose de 0,2 a 8,3 Gy, com queda gradativa em função do tempo para doses mais altas (10, 20 e 40Gy). Dados obtidos mostraram pouco dano citogenético nos pacientes após a exposição terapêutica com radioiodo, o que sugere um tratamento seguro e eficaz para os pacientes dos dois grupos. Pacientes do grupo A, no entanto, obtiveram uma melhor qualidade de vida com o uso do r-hTSH. Estudos in vitro com irradiação interna (131I) e externa (60Co) com ou sem r-hTSH, apontam a necessidade de uma estratégia terapêutica alternativa para contornar a perda da habilidade das células tireoidianas (WRO) em concentrar o radioiodo, responsável pelo relativo insucesso da iodoterapia em pacientes com CDT. / Tese (Doutorado em Tecnologia Nuclear) / IPEN/T / Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

Organisms are comprised of many cells with multiple distinct cell types, each of which must be decided precisely to ensure proper formation of a functional organism. In C. elegans, the basic helix-loop helix transcription factor HLH-2 is required for the specification of the anchor cell, or AC. The AC arises from a group of four somatic gonad cells, all of which initially express HLH-2. Two of the four cells, which we call β cells, lose AC competence early and instead become ventral uterine precursor cells, or VUs. We call the remaining two cells α cells. One α cell becomes the AC, while the other becomes a VU. Which α cell becomes the AC is random—50% of the time one α cell becomes the AC, while the other 50% of the time the other α cell becomes the AC. The choice of which cell becomes the AC and which becomes the VU is called the AC/VU decision, and occurs through reciprocal signaling by LIN-12/Notch and its ligand LAG-2/DSL. At first, both α cells express similar levels of lin-12 and lag-2. As the AC/VU decision progresses, the AC expresses higher levels of lag-2, and the VU expresses higher levels of lin-12. By this time, HLH-2 is only present in the specified AC, while it is post-translationally degraded in VUs. The mechanism by which HLH-2 is degraded and the consequences of disrupting its degradation on AC specification are unknown. In this work, we studied the function and regulation of HLH-2 during two stages of somatic gonad development. First, we used long-term fluorescence microscopy to visualize HLH-2 over the course of somatic gonad development. We found that HLH-2 expression begins in the parents of the α and β cells a consistent amount of time after their birth, and that the parent cell that first expresses HLH-2 almost always gives rise to the α cell that becomes the VU, while the second cell to express HLH-2 gives rise to the AC. This led us to study the effect of a loss of hlh-2 activity in the α and β cells. We generated an α and β cell-specific hlh-2(0) allele using genome editing tools and found that LIN-12 protein is not present in the absence of hlh-2 activity. Based on this discovery, we conceived a model where HLH-2 expression biases the first-expressing cell towards the VU fate by endowing it with an edge in lin-12 activity. Next, we focused on restriction of HLH-2 to the AC. Typically, HLH-2 protein is degraded in VUs, which we hypothesized was a crucial step in restriction of the AC fate to a single cell. We found that in a lin-12(0) background, HLH-2 is stabilized in VUs even when the resulting cell does not become an AC, indicating that lin-12 directly promotes HLH-2 degradation. This led us to search for a lin-12-regulated factor that targets HLH-2 for degradation in VUs. We identified seven ubiquitin-related genes whose depletion resulted in stabilized HLH-2 in VUs, but surprisingly did not cause an AC/VU defect. We suspect that HLH-2 degradation in VUs is one of multiple negative regulatory mechanisms that ensure the robustness of the AC/VU decision. The following research contributes new insights into how stochastic cell fate decisions amplify noise to ensure a consistent and reproducible outcome.

DNA methylation regulates gene expression through a complex network of protein/protein and protein/DNA interactions in chromatin. The maintenance methylase, DNA methyltransferase 1 (DNMT1), is a prominent enzyme in the process that is linked to DNA replication and drives the heritable nature of epigenetic modifications in somatic cells. The mechanistic details that explain how DNMT1 catalytic action is directed in a chromatin setting are not well understood. We hypothesize that post translational modifications and a variety of protein-protein interactions processes are key regulatory elements that set the methylation of CpG elements essential for normal growth behavior in somatic cells. These fundamental processes can be disrupted by DNA damage leading to inappropriate gene silencing and loss of growth control in somatic cells. First, we show that DNMT1 is post-translationally modified by sumoylation and we have mapped these sumoylation sites by defined mutations. Sumoylated DNMT1 is catalytically active on genomic DNA in vivo and substantially increases the enzymatic activity of DNMT1 both in vitro and in chromatin. These data establish that sumoylation modulates the endogenous activity of a prominent epigenetic maintenance pathway in cells. Second, we investigated novel mechanisms whereby somatic cells can erase then reset DNA methylation events in somatic cells. In this study, the relationship between DNA damage and gene silencing was explored. To this end, we generated a HeLa cell line containing a specialized GFP reporter cassette (DRGFP) containing two mutated GFP genes and a unique ISceI restriction endonuclease site. These cells do not express GFP. A unique double strand break is then delivered by transfecting in the gene for I-SceI. About 4% of the cells produced a functional GFP by gene conversion and homologous recombination (HR); however roughly half iv of the GFP recombinants expressed the gene poorly and this was attributed to gene silencing. Silencing of the GFP expressing cell clones was due to DNA methylation and could be reversed using a drug that inhibits global methylation (5-aza-2'-deoxycytidine). Approximately half of the repaired genes were heavily methylated, and half were hypomethylated. That is, a key intermediate methylation state after HR repair is hemimethylated DNA, defined as methylation limited to one strand. Evidence is given that DNMT1 is acting as a de novo methylase at the HR repair patches in cells. Moreover, the DNA damage inducible protein, GADD45, interacts specifically with the catalytic domain of DNMT1 and GADD45 binds with extremely high affinity to hemimethylated DNA sites. Thus, GADD45 is a key regulatory element in silencing of HR repaired DNA segments and appears to inhibit the activity of DNMT1. Consistent with these results, we found that GADD45 increased the expression of recombinant GFP following HR repair, further suggesting its role in orchestrating strand specific DNA methylation by DNMT1. Since these experiments were performed in live cells, there is strong physiological relevance. We propose that DS DNA damage and the resulting HR process involves precise, strand selected DNA methylation mediated by the prominent methylase enzyme, DNMT1. Moreover, DS DNA break repair through HR and gene conversion, may potentially erase and reset DNA methylation patterns and therefore alter the expression of repaired genes. The overall process is tightly regulated by the DNA damage inducible protein GADD45, which may coordinate strand specific methylation by recruiting DNMT1 to HR repair templates. The ability of GADD45 to modulate DNMT1 catalytic activity may explain its role as a passive mediator of demethylation that has been reported by other groups. The overall process of silencing post DNA repair is a strong evolutionary force that may predispose cells to malignant transformation

A bidirectional selection experiment for increased and decreased somatic cell counts (SCC) in milk was conducted with two selected lines (high line or HSCC, low line or LSCC) and one control line (CSCC) of mice. Distribution of milk SCC in mice was 4 to 5 times the distribution in Holsteins. The shape of the lactation curve of mice was similar to that of Holsteins with maximum yield at day 7 (2.06 gms). The phenotypic regression of lactation milk yield on lactation milk SCC (-0.276) was significant (P < .05) and indicated that dams with higher SCC produce less milk. Small phenotypic correlations of milk SCC with blood SCC (-0.09) and percentage phagocytic cells (-0.06) were found, indicating that these traits are unrelated. A small but significant (P < .05) negative correlation (-0.14), was found between response to endotoxin challenge and milk SCC indicating that dams with inherently higher milk SCC responded less to endotoxin challenge than dams with lower milk SCC. No major pathogens which cause mastitis in cattle were detected in milk of mice. In addition, the bacteria identified (Bacillus sp., Corynebacterium sp. etc) did not cause any serious infections and/or increase in milk SCC in mice. Selection for high and low milk SCC produced a symmetrical response in the two selected lines (HSCC and LSCC), such that after 7 generations of selection, the two lines differed by more than 500,000 cells/ml of milk. A small negative genetic regression ( -0.162) of milk yield on milk SCC suggested a small correlated response in yield opposite in direction from the direct response for milk SCC. Small negative genetic regressions of blood SCC and percentage phagocytic cells on milk SCC ( -0.087 and -3.492) suggested that these three traits are genetically independent. Selection on milk SCC did not result in change either in total leukocytic cells per ml of blood or in percentage phagocytic leukocytes in blood. A negative genetic regression of response to challenge on milk SCC (-3.201) was found suggesting that selection for low milk SCC results in an increase of the ability of the individual mouse to elevate milk SCC after an injection with E. coli endotoxin. However, more data are needed to confirm this conclusion. Phenotypic correlations between milk SCC and several measures of fitness and genetic regressions of these measures on milk SCC were negligible. / Ph. D.

No / Male germ stem cells are responsible for transmission of genetic information to the next generation. Some chemicals exert a negative impact on male germ cells, either directly, or indirectly affecting them through their action on somatic cells. Ultimately, these effects might inhibit fertility, and may exhibit negative consequences on future offspring. Genotoxic anticancer agents may interact with DNA in germ cells potentially leading to a heritable germline mutation. Experimental information in support of this theory has not always been reproducible and suitable in vivo studies remain limited. Thus, alternative male germ cell tests, which are now able to detect phase specificity of such agents, might be used by regulatory agencies to help evaluate the potential risk of mutation. However, there is an urgent need for such approaches for identification of male reproductive genotoxins since this area has until recently been dependent on in vivo studies. Many factors drive alternative approaches, including the (1) commitment to the principles of the 3R's (Replacement, Reduction, and Refinement), (2) time-consuming nature and high cost of animal experiments, and (3) new opportunities presented by new molecular analytical assays. There is as yet currently no apparent appropriate model of full mammalian spermatogenesis in vitro, under the REACH initiative, where new tests introduced to assess genotoxicity and mutagenicity need to avoid unnecessary testing on animals. Accordingly, a battery of tests used in conjunction with the high throughput STAPUT gravity sedimentation was recently developed for purification of male germ cells to investigate genotoxicity for phase specificity in germ cells. This system might be valuable for the examination of phases previously only available in mammals with large-scale studies of germ cell genotoxicity in vivo. The aim of this review was to focus on this alternative approach and its applications as well as on chemicals of known in vivo phase specificities used during this test system development. / Natural Science Fund of Shandong Province, China (No. ZR2012DM014) and the People’s Livelihoods Science and Technology Project of Qingdao, Shandong Province, China (13-1-3-73-nsh).

A caseína e os ácidos graxos livres (AGL) são importantes componentes do leite relacionados às suas características industriais e sensoriais. Alguns fatores são responsáveis por alterações em suas concentrações, dentre eles, pode-se destacar as condições de armazenamento, além da agitação e, principalmente, a contagem de células somáticas (CCS). Para estudar tais alterações, avaliou-se através do presente estudo o efeito da temperatura de armazenamento (- 20oC e 7oC) e da idade das amostras (3, 6, 9 e 12 dias), assim como da CCS (CCS1: 400 mil, CCS2:400-750 mil e CCS3: 750 mil células somáticas/mL de leite). O efeito das condições de armazenamento sobre a caseína e os AGL foi avaliado no primeiro estudo. O efeito da CCS sobre a caseína e os AGL, por outro lado, foi avaliado no segundo estudo. No primeiro estudo, observou-se aumento nos teores de AGL ao longo do tempo, ou seja, acompanhando o aumento do período de armazenamento, com médias superiores em amostras resfriadas (7oC), em relação às congeladas (-20oC). Desta forma, sugere-se que análises laboratoriais devem ser realizadas em até três dias para este componente, devido ao seu aumento progressivo em amostras resfriadas. Para a caseína, entretanto, não foi identificada interação entre os fatores idade e temperatura. As médias deste componente não diferiram considerando-se as condições de armazenamento avaliadas, indicando que as análises para este componente podem ser realizadas até doze dias após a coleta, independente da temperatura de armazenamento. No segundo estudo, identificou-se interação entre classes de CCS e época de coleta, para caseína. A partir dos resultados de AGL, pode-se concluir que o leite encontra-se com altas concentrações deste componente, quando coletado na propriedade rural, sendo também observada influência da CCS sobre as concentrações de caseína e AGL no leite cru. Os AGL apresentaram incrementos significativos comparando-se amostras coletadas em diferentes locais, no trajeto da fazenda à indústria. Por outro lado, comparando-se os mesmos locais: tanque, rota e silo, as médias de caseína não diferiram. Observou-se correlação entre as variáveis CCS e caseína e CCS e AGL. / The casein and the free fatty acids (FFA) are important milk components related to its industrial and sensory characteristics. Some factors are responsible for changes in their concentration among them can highlight the storage conditions, as well as agitation and, especially, the somatic cell count (SCC). To study such changes, we assessed through the present study the effect of storage temperature (-20oC and 7oC) and the age of samples (3, 6, 9 e 12 days), as well as the CCS (CCS1: 400 mil; CCS2: 400-750 mil; CCS3: 750 mil somatic cells/mL of milk). The effect of CCS storage conditions on casein and FFA was evaluated in the first study. The effect of CCS on casein and FFA moreover, was evaluated in the second study. In the first study, it was observed increased levels the AGL over time, ie, accompanying the increase of the storage period, with means higher in refrigerated samples (7oC), in relation to frozen samples (- 20oC). Thus, it is suggested that laboratory examinations shall be performed up to three days to this component, due to their progressive increase in refrigerated samples. For casein, however, was not identified interaction between the factors age and temperature. The mean of this component did not differ considering the storage conditions, indicating that the analyzes for this component can be made until twelve days after collection, regardless of storage temperature. In the second study, we identified interactions between CCS classes and seasons, for casein. From the FFA results, we can conclude that milk meets with high concentrations of this component, when collected in the rural property, being also observed influence of CCS on concentrations of casein and FFA in raw milk. The FFA showed significant increases compared to samples collected at different locations on the path from farm to industry. On the other hand, comparing the same locations, tank, route and silo, the casein average did not differ. Correlation was observed between the variables casein and CCS and FFA and CCS.

Com a finalidade de estabelecer os valores de referência das características físico-químicas e celulares do leite de bovinos da raça Jersey, criados no Estado de São Paulo, durante o primeiro mês de lactação, bem como avaliar a influência da fase colostral, do número de lactações e do crescimento bacteriano em quartos mamários sadios na composição do leite, examinaram-se 617 amostras de leite, sendo 418 amostras provenientes de quartos mamários sadios e sem crescimento bacteriano e 199 amostras obtidas de quartos mamários sadios com crescimento bacteriano. O leite foi colhido assepticamente antes da ordenha e os seguintes parâmetros avaliados: pH, eletrocondutividade, cloreto, lactose, índice cloretos/lactose, gordura, proteína, sólidos totais, Califórnia Mastitis Tes (CMT) e contagem de células somáticas. Demonstrou-se a significativa influência do primeiro mês de da lactação sobre as características físico-químicas do leite, pois os valores de pH foram menores nos três primeiros dias de lactação e passaram a aumentar de maneira gradual, a eletrocondutividade diminuiu nos primeiros cinco dias de lactação, os teores de cloretos e o índice cloretos/lactose diminuem, ocorre um aumento abrupto dos teores de lactose nos dois primeiros dias, depois esse aumento passa a ocorrer de maneira gradual, os teores de gordura variaram nos primeiros dias e diminuíram a partir do 7º dia de lactação, os teores de proteína e sólidos totais diminuem, A fase da lactação também apresentou significativa influência sobre a freqüência de reações do CMT e na contagem de células somáticas. A freqüência de reações negativas do CMT foi maior nas primeiras 12 horas de lactação e a contagem de células somáticas diminuíram conforme o evoluir do primeiro mês. As características físico-químicas e celulares do leite sofreram influência do número de lactações, para as seguintes variáveis: cloretos que foi maior nas pluríparas, lactose que foi maior nas primíparas, índice cloretos/lactose que foi maior nas pluríparas e proteína que foi maior nas pluríparas. Demonstrou-se no leite proveniente de quartos mamários sadios e em cujas amostras houve crescimento bacteriano a influência do resultado do exame microbiológico sobre a composição do leite, pois os valores pH, eletrocondutividade, proteína e contagem de células somáticas foram maiores nas amostras de leite com crescimento bacteriano e a freqüência de reações negativas ao Califórnia Mastitis Test-CMT foram menores nas amostras de leite em que houve crescimento. Considerando-se as primeiras 24 horas após o parto foram estabelecidos os seguintes valores de referência para as características físico-químicas e celulares do colostro de bovinos sadios, da raça Jersey, criados no Estado de São Paulo: pH - entre 6,37 ± 0,14 e 6,43 ± 0,23; Eletrocondutividade - entre 5,24 ± 0,61 e 6,00 ± 0,16 mS/cm; Cloretos - entre 154,10 ± 29,03 e 155,50 ± 56,66 mg/dl; Lactose - entre 3,14 ± 0,66 e 3,69 ± 0,77 g/dl; Índice Cloretos/Lactose- entre 4,80 ± 3,99 e 5,22 ± 1,84; Gordura - 1,35 ± 1,17 e 2,90 ± 2,29 g/dl; Proteína - entre 8,09 ± 2,35 e 10,95 ± 1,24 g/dl; Sólidos Totais - entre 13,01 ± 1,98 e 18,18 ± 3,20 g/dl, e número de células somáticas - entre 946.444 ± 1.1198.319 e 1.355.273 ± 1.829.318 células/ml. A freqüência de ocorrência de reações do CMT foi: negativos - entre 87,8 e 96,30 %; meia cruz entre 0,00 e 4,87 %; uma cruz 0,00 %; duas cruzes - 0,00 % e três cruzes - entre 3,70 e 7,31 %. Entre o 2º e 7º dia de lactação foram estabelecidos os seguintes valores de referência: pH - entre 6,50 ± 0,15 e 6,61 ± 0,16; Eletrocondutividade - entre 5,12 ± 0,66 e 5,72 ± 0,69 mS/cm; Cloretos - entre 89,97 ± 24,80 e 114,40 ± 39,28 mg/dl; Lactose - entre 4,18 ± 0,50 e 4,42 ± 0,57 g/dl; Índice Cloretos/Lactose- entre 2,23 ± 1,78 e 2,94 ± 2,03; Gordura - 2,06 ± 1,50 e 3,09 ± 2,19 g/dl; Proteína - entre 4,09 ± 0,35 e 4,83 ± 0,66 g/dl; Sólidos Totais - entre 12,07 ± 1,33 e 12,98 ± 1,93 g/dl e o número de células somáticas - entre 555.553 ± 1.265.531 e 874.677 ± 1.443.014 células/ml. A freqüência de ocorrência de reações do CMT foi: negativa: - entre 72,34 e 87,20 %; meia cruz - entre 2,00 e 6,38 %; uma cruz - entre 2,00 e 8,51 %; duas cruzes - entre 2,32 e 8,51 % e três cruzes - entre 2,12 e 14,00 %. Entre o 8º e 30º dia de lactação foram estabelecidos os seguintes valores de referência: pH - entre 6,61 ± 0,12 e 6,71 ± 0,13; Eletrocondutividade - entre 5,14 ± 0,53 e 5,23 ± 0,59 mS/cm; Cloretos - entre 92,58 ± 29,08 e 96,73 ± 28,86 mg/dl; Lactose - entre 4,42 ± 0,51 e 4,74 ± 0,41 g/dl; Índice Cloretos/Lactose- entre 2,11 ± 0,96 e 2,20 ± 1,01; Gordura - 1,96 ± 0,99 e 2,49 ± 1,27 g/dl; Proteína - entre 3,56 ± 0,29 e 4,02 ± 0,72 g/dl; Sólidos Totais - entre 11,23 ± 1,13 e 11,70 ± 1,27 g/dl e o número de células somáticas - entre 121.632 ± 316.269 e 433.419 ± 1.297.486 células/ml. A freqüência de ocorrência de reações do CMT foi: negativos - entre 93,10 e 93,54 %; meia cruz - entre 0,00 e 5,17 %; uma cruz - entre 0,00 e 1,61 %; duas cruzes - entre 1,61 e 1,72 % e três cruzes - entre 0,00 e 3,22 %. / With the aim to establish reference values of the physicochemical and cellular characteristics of milk from Jersey cows, raised in the State of São Paulo, during the first month of lactation, as well as to evaluate the influence of the colostral phase, the number of lactations, and the bacterial growth within health mammary glands on milk composition, 617 milk samples were examined: 418 were obtained from healthy mammary glands without bacterial growth and 199 samples obtained from health mammary glands with bacterial growth. Milk samples were collected aseptically before milking and the following parameters were evaluated: pH, electrical conductivity, chlorate, lactose, chlorate/lactose ratio, fat, proteins, total solids, California Mastitis Test (CMT), and somatic cell count. Significant influences was demonstrated during the first month of lactation relative to the physicochemical characteristics, since the pH values were lower during the first three days of lactation and were increased gradually; electrical conductivity was reduced during the first five days of lactation; the levels of chlorate and the chlorate/lactose ratio were reduced; there was an abrupt increase in the levels of lactose during the first two days, after which this increase was gradual; the levels of fat were varied during the first days and were reduced with effect from the 7th day of lactation; the levels of protein and total solids were reduced. The lactation phase also demonstrated significant influence on the frequency of CMT reactions and the somatic cell count. The frequency of the negative CMT reactions was higher during the first 12 months of lactation while the somatic cell count was reduced during the same period. The physicochemical and cellular characteristics of milk were influenced by the number of lactations for the following variables: chlorate was higher in pluriparous cows; lactose was higher in primiparous cows; the chlorate/lactose ratio was higher in pluriparous cows, and protein was elevated in pluriparous cows. It was demonstrated that milk obtained from healthy mammary glands with bacterial growth within the samples influenced the milk composition since the pH values, electrical conductivity, protein, and the somatic cell count were higher in samples from milk bacterial growth, and the frequency of negative California Mastitis Test reactions were lower in samples with bacterial growth. Considering the first 24 hours after partition the following reference values were established for physicochemical and cellular characteristics of milk of Jersey cows raised in the State of São Paulo: pH, between 6.37 ± 0.14 and 6.43 ± 0.23; electrical conductivity, between 5.24 ± 0.61 and 6.00 ± 0.16 mS/cm; chlorates, between 154.10 ± 29.03 and 155.50 ± 56.66 mg/dl; lactose, between 3.14 ± 0.66 and 3.69 ± 0.77 g/dl; chlorates/lactose ratio, between 4.80 ± 3.99 and 5.22 ± 1.84; fat, between 1.35 ± 1.17 and 2.90 ± 2.29 g/dl; protein, between 8.09 ± 2.35 and 10,95 ± 1.24 g/dl; total solids, between 13.01 ± 1.98 and 18.18 ± 3.20 g/dl; and number of somatic cells, between 946.444 ± 1.1198.319 and 1.355.273 ± 1.829.318 cells/ml. The frequency of occurrence of negative CMT reactions was: negative, between 87.8 and 96.30%; half cross, between 0.00 e 4.87%; one cross, 0.00 %; two crosses, 0.00 %; and three crosses, between 3.70 e 7.31%. The following reference values were established between the 2nd and 7th day of lactation: pH, between 6.50 ± 0.15 and 6.61 ± 0.16; electrical conductivity, between 5.12 ± 0.66 and 5.72 ± 0.69 mS/cm; chlorates, between 89.97 ± 24.80 and 114.40 ± 39.28 mg/dl; lactose, between 4.18 ± 0.50 and 4.42 ± 0.57 g/dl; chlorate/lactose ratio, between 2.23 ± 1.78 e 2.94 ± 2.03; fat, between 2.06 ± 1.50 and 3.09 ± 2.19 g/dl; protein, between 4.09 ± 0.35 and 4.83 ± 0.66 g/dl; total solids, between 12.07 ± 1.33 and 12.98 ± 1.93 g/dl; and number of somatic cells, between 555.553 ± 1.265.531 and 874.677 ± 1.443.014 cells/ml. The frequency of the occurrence of CMT reactions was: negative, between 72.34 and 87.20%; half cross, between 2.00 and 6.38%; one cross, between 2.00 and 8.51 %; two crosses, between 2.32 and 8.51%; and three crosses, between 2.12 and 14.00%. The following reference values were established between the 8th and 30th day of lactation: ph, between 6.61 ± 0.12 and 6.71 ± 0.13; electrical conductivity, between 5.14 ± 0.53 and 5.23 ± 0.59 mS/cm; chlorates, between 92.58 ± 29.08 and 96.73 ± 28.86 mg/dl; lactose, between 4.42 ± 0.51 and 4.74 ± 0.41 g/dl; chlorates/lactose ratio, between 2.11 ± 0.96 and 2.20 ± 1.01; fat, between 1.96 ± 0.99 and 2.49 ± 1.27 g/dl; protein, between 3.56 ± 0.29 and 4.02 ± 0.72 g/dl; total solids, between 11.23 ± 1.13 and 11.70 ± 1.27 g/dl; and the number of somatic cells, between 121.632 ± 316.269 e 433.419 ± 1.297.486 cells/ml. The frequency of the occurrence of CMT reactions was: negative, between 93.10 and 93.54 %; half cross, between 0.00 e 5.17%; one cross, between 0.00 and 1.61%; two crosses, 1.61 and 1.72%; and three crosses, between 0.00 and 3.22%.