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1.
J Dairy Sci ; 104(2): 1445-1453, 2021 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-33309367

RESUMO

The study aimed to evaluate the effects of linseed and oregano supplementation to the diet of goats on fatty acid profile and sensory properties of Padraccio, a typical cheese produced during spring through summer in the Basilicata region (southern Italy). Extruded linseed and dried oregano inflorescences were integrated in the pelleted concentrate supplementation (500 g/head per day) in 21 grazing goats that were randomly assigned, 7 per group, to the following experimental treatments: concentrate, concentrate with addition of linseed, and concentrate with addition of linseed and oregano. Pooled milk from each group was used in cheesemaking. From a nutritional perspective, integration of extruded linseed in the goat diet improved the fatty acid profile of Padraccio cheese. Moreover, the cheese from this group evidenced the highest scoring on color, flavor, texture, and overall liking.


Assuntos
Queijo/análise , Ácidos Graxos/análise , Linho , Cabras , Leite/química , Origanum , Animais , Dieta/veterinária , Suplementos Nutricionais , Feminino , Itália , Lactação
2.
J Dairy Sci ; 102(8): 6750-6755, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31155256

RESUMO

The use of a sterilized product for washing cows' udders before milking may be useful to reduce or prevent Clostridium tyrobutyricum contamination, the main cause of the late-blowing defect in hard and semi-hard cheeses. The aim of this research was to evaluate the antibacterial efficacy of an experimental formula containing 15% condensed donkey milk (lysozyme content 825 mg/L). The antimicrobial activity of condensed milk was first evaluated in vitro, using the disk diffusion method, on the following microorganisms: Bacillus megaterium, Bacillus mojavensis, Clavibacter michiganensis, and Clostridium tyrobutyricum. These results were compared with the effects of 2 antibiotics, ampicillin (100 mg/mL) and kanamycin (50 mg/ mL), and a commercial pre-dipping formula. The results showed that the inhibitory activity of lysozyme from donkey milk on all the considered microorganisms was higher than that of the commercial product and similar to that of the 2 antibiotics. Next, the formula with lysozyme was compared with a commercial pre-dipping formula on 48 lactating cows (24 cows in each group). Skin tests were performed on teats before and after pre-dipping. Results showed that the formula with condensed milk significantly reduced the clostridial load detected on the skin of cows' teats before cleaning (-55.61% vs. -27.99%) and in the bulk milk of the experimental group compared with the control group with commercial product (-52.53% vs. -32.42%).


Assuntos
Bovinos , Clostridium tyrobutyricum/efeitos dos fármacos , Equidae , Glândulas Mamárias Animais/microbiologia , Leite/enzimologia , Muramidase/farmacologia , Ampicilina/farmacologia , Animais , Anti-Infecciosos/farmacologia , Queijo/microbiologia , Clostridium tyrobutyricum/crescimento & desenvolvimento , Feminino , Canamicina/farmacologia , Lactação
3.
J Dairy Sci ; 99(7): 5173-5179, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27157571

RESUMO

Thermal treatments are used to improve milk microbial safety, shelf life, and biological activity of some of its components. However, thermal treatments can reduce the nutritional quality of milk, affecting the molecular structure of milk proteins, such as lysozyme, which is a very important milk component due to its antimicrobial effect against gram-positive bacteria. Jenny milk is characterized by high lysozyme content. For this reason, in the last few years, it has been used as an antimicrobial additive in dairy products as an alternative to hen egg white lysozyme, which can cause allergic reactions. This study aimed to investigate the effect of pasteurization and condensation on the concentration and antimicrobial activity of lysozyme in jenny milk. Furthermore, lysozyme quantity and activity were tested in raw and pasteurized milk after condensation at 40 and 20% of the initial volume. Reversed-phase HPLC was performed under fluorescence detection to monitor lysozyme in milk samples. We evaluated the antimicrobial activity of the tested milk against Bacillus megaterium, Bacillus mojavensis, Clavibacter michiganensis, Clostridium tyrobutyricum, Xanthomonas campestris, and Escherichia coli. Condensation and pasteurization did not affect the concentration or antimicrobial activity of lysozyme in jenny milk, except for B. mojaventis, which showed resistance to lysozyme in milk samples subjected to heat treatments. Moreover, lysozyme in jenny milk showed antimicrobial activity similar to synthetic antibiotics versus some gram-positive strains and also versus the gram-negative strain X. campestris.


Assuntos
Anti-Infecciosos/análise , Leite/química , Muramidase/análise , Pasteurização , Animais , Equidae , Temperatura Alta
4.
J Dairy Sci ; 99(1): 228-33, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26506544

RESUMO

The addition of jenny milk during cheesemaking has been recommended as a viable alternative to egg lysozyme for controlling late blowing defects. However, little is known on the sensory properties of the cheeses made with jenny milk. In this study, the effect of the addition of jenny milk during cheesemaking on sensory properties and consumer acceptability of cheese was evaluated. A sensory profile was carried out by 10 trained panelists on 4 cow milk cheese types. Two types of cheeses were made by adding jenny milk to cow milk during cheesemaking; the cheeses were then left to ripen for 45 and 120 d. The remaining 2 cheese types were made with only cow milk and were also left to ripen for 45 and 120 d. The attributes generated by a quantitative descriptive analysis sensory panel were effective for discriminating the 4 products. Among them, added jenny milk samples aged for 45 d had the highest intensity of some appearance descriptors (structure and color uniformity), as well as the highest intensity of sweetness. The analysis of acceptability data obtained from 89 consumers showed that added jenny milk aged for 45 d was the most preferred type of cheese, whereas no significant differences were found among the other products, which had higher intensity of bitter, salty, acid milk, and so on.


Assuntos
Bovinos/fisiologia , Queijo/análise , Leite/química , Animais , Queijo/normas , Cor , Feminino , Leite/metabolismo , Paladar
5.
J Dairy Sci ; 98(8): 5133-42, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26074234

RESUMO

The occurrence of late blowing defects in cheese produces negative effects on the quality and commercial value of the product. In this work, we verified whether the addition of raw jenny milk to bulk cow milk reduced the late blowing defects in semihard cheeses. During cheesemaking, different aliquots of jenny milk were poured into 2 groups of 4 vats, each containing a fixed amount of cow milk. A group of cheeses was created by deliberately contaminating the 4 vats with approximately 3 log10 cfu/mL milk of Clostridium tyrobutyricum CLST01. The other 4 vats, which were not contaminated, were used for a second group of cheeses. After 120 d of ripening, some physical, chemical, and microbiological parameters were evaluated on the obtained semihard cheeses. Differences in sensory properties among cheeses belonging to the uncontaminated group were evaluated by 80 regular consumers of cheese. Our results showed that the increasing addition of jenny milk to cow milk led to a reduction of pH and total bacterial count in both cheese groups, as well as C. tyrobutyricum spores that either grew naturally or artificially inoculated. We observed a progressive reduction of the occurrence of late blowing defects in cheese as consequence of the increasing addition of jenny milk during cheese making. Moreover, the addition of jenny milk did not affect the acceptability of the product, as consumers found no difference among cheeses concerning sensorial aspects. In conclusion, the important antimicrobial activity of lysozyme contained in jenny milk has been confirmed in the current research. It is recommend for use as a possible and viable alternative to egg lysozyme for controlling late blowing defects in cheese.


Assuntos
Queijo/análise , Queijo/microbiologia , Leite/química , Animais , Bovinos , Equidae , Feminino , Muramidase/metabolismo
6.
Phys Rev Lett ; 112(16): 163002, 2014 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-24815646

RESUMO

Rotational levels of molecular free radicals can be tuned to degeneracy by using laboratory-scale magnetic fields. Because of their intrinsically narrow width, these level crossings of opposite-parity states have been proposed for use in the study of parity-violating interactions and other applications. We experimentally study a typical manifestation of this system using BaF138. Using a Stark-mixing method for detection, we demonstrate level-crossing signals with spectral width as small as 6 kHz. We use our data to verify the predicted line shapes, transition dipole moments, and Stark shifts and to precisely determine molecular magnetic g factors. Our results constitute an initial proof of concept for use of this system to study nuclear spin-dependent parity-violating effects.

7.
J Dairy Sci ; 96(6): 3547-50, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23587377

RESUMO

Late blowing on semihard and hard cheese may have an important economic effect on dairy production. Many studies have attempted to prevent this defect by physical treatment, the use of additives, and the use of bacteriocins. In this paper, we look at the effect of jenny milk as an inhibitor of blowing caused by clostridia and coliforms in ewe cheese making. Bulk ewe and jenny milk samples were collected in the morning by mechanical milking and were refrigerated at 4°C. On the collected samples, the count of somatic cells, coliforms, Clostridium butyricum, and Escherichia coli were determined. The bulk raw milk was divided in two 45-L vats: vat 1 was used as a control, whereas 0.5L of jenny milk was added to vat 2. Four semihard cheeses, weighing about 2 kg each, were made from each vat. Cheese making was replicated twice. After a ripening period of 60 d, the count of coliforms and of C. butyricum was determined. In the treated group, a significant inhibition of coliform bacteria was observed. The addition of jenny milk in cheese making may prove to be a useful and innovative approach for the inhibition of spore-forming clostridia strains.


Assuntos
Queijo/microbiologia , Equidae , Leite/química , Leite/microbiologia , Animais , Antibacterianos , Carga Bacteriana , Clostridium butyricum , Escherichia coli , Feminino , Manipulação de Alimentos/métodos , Muramidase/análise , Ovinos , Esporos Bacterianos/citologia
8.
J Dairy Sci ; 95(6): 2910-5, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22612928

RESUMO

The aim of this research was to study the influence of lactation stage and foaling season on some qualitative aspects of milk in South Italian jenny rearing. Milk samples were collected monthly from 23 jennies, that foaled in 2 different periods: spring and summer. On milk, the following parameters were measured: pH and titratable acidity; protein, fat, lactose, dry matter, and ash contents; and somatic cell count. Analysis of variance showed the effect of foaling season and of lactation stage. Milk production was highest in summer at 30 d and 60 d (1.58 and 1.78 L, respectively), and in spring at 120 d (1.25 L). The total protein content was highest in summer lactation at 30 d and 90 d (14.8 and 13.9 g/L). Lactose, dry matter, and ash contents (g/L) were highest in summer lactation at 30 d (54.0, 78.1, and 5.0 respectively). Jenny milk was shown to be poor in protein and fat and rich in lactose. Producing jenny milk could be an interesting, profitable, and alternative activity for farmers, mainly in southern marginal areas.


Assuntos
Equidae/metabolismo , Leite/metabolismo , Animais , Equidae/fisiologia , Gorduras/análise , Feminino , Lactação/metabolismo , Lactação/fisiologia , Lactose/análise , Leite/química , Leite/normas , Proteínas do Leite/análise , Estações do Ano
10.
J Pharm Sci ; 65(11): 1600-5, 1976 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-993990

RESUMO

Chlorpromazine-induced depression of rectal temperatures in rabbits kept at 20 degrees was used to determine relative biophasic drug levels corresponding to observed hypothermic response intensities, which then served to establish a triexponential linear mathematical model describing drug transference and drug action in this system. Comparisons of various experimentally known, slow intravenous infusion drug inputs of chlorpromazine with drug inputs computed by deconvolution, using the derived model and observed temperature depressions, served to verify the accuracy of the model for the 0.50-4.0 mg/kg dosage range.


Assuntos
Temperatura Corporal/efeitos dos fármacos , Clorpromazina/farmacologia , Animais , Disponibilidade Biológica , Clorpromazina/administração & dosagem , Clorpromazina/metabolismo , Computadores , Depressão Química , Relação Dose-Resposta a Droga , Cinética , Masculino , Modelos Biológicos , Coelhos , Reto , Fatores de Tempo
11.
Psychopharmacologia ; 45(2): 167-9, 1975 Dec 31.
Artigo em Inglês | MEDLINE | ID: mdl-1215446

RESUMO

Mice were housed either individually ("isolated") or in groups of 20-25 ("aggregated") for 5-9 weeks or for 22 weeks. A decreased incorporation of radioactivity into brain from subcutaneously-administered U-14C-D-glucose occurred in "isolated" mice as compared to grouped animals. Amphetamine, administered before labelled glucose, produced a dose-dependent decrease of radioactivity which was selective to the brains of the "isolated" mice. The data support the correlation between isolation-induced changes in behavior and central metabolic pathways and indicate further that these changes may be altered by administration of psycho-active agents.


Assuntos
Encéfalo/efeitos dos fármacos , Dextroanfetamina/farmacologia , Meio Ambiente , Glucose/metabolismo , Animais , Encéfalo/metabolismo , Aglomeração , Relação Dose-Resposta a Droga , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Isolamento Social
12.
Physiol Behav ; 14(2): 201-6, 1975 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-1172244

RESUMO

Alterations in shock-induced aggressive behavior, general emotional reactivity and flinch thresholds in 61 and 82 day old male rats were analyzed at either 3 or 6 weeks following castration. Castrated animals were significantly less aggressive than sham-operated controls at the 6 week but not the 3 week interval. These findings could not be attributed to changes in flinch threshold as neither treatment nor time affected this measure. With regard to emotionality, castrated animals were significantly more reactive than the control animals at the 3 week but not 6 week interval. The data are interpreted as indicating that castration altered shock-induced aggression by preventing a maturational increase in such behavior. These behavioral alterations are compared to previously reported time-dependent changes in brain monoaminergic dynamics following gonadectomy. The conclusions support the concept of a necessary balance between catecholaminergic and serotonergic systems with regard to affective behavior.


Assuntos
Agressão/fisiologia , Comportamento Animal/fisiologia , Castração , Emoções/fisiologia , Fatores Etários , Animais , Encéfalo/metabolismo , Catecolaminas/metabolismo , Eletrochoque , Comportamento Exploratório/fisiologia , Humanos , Ácido Hidroxi-Indolacético/metabolismo , Masculino , Modelos Biológicos , Atividade Motora/fisiologia , Comportamento Predatório/fisiologia , Ratos , Tempo de Reação/fisiologia , Fatores Sexuais , Fatores de Tempo
13.
Pharmacology ; 13(1): 20-6, 1975.
Artigo em Inglês | MEDLINE | ID: mdl-1171469

RESUMO

Sensitivity of the central nervous system (CNS) to the hypnotic effect of hexobarbital was assessed by analytical, pharmacokinetic, and electroencephalographic techniques in male and female rats and in mice of both sexes by the first two techniques. These experimentally and conceptually diverse measures yielded strikingly similar estimates of CNS sensitivity to hexobarbital which was independent of both species and sex, while well known species ans sex (rat) differences in duration of response to hexobarbital were demonstrated.


Assuntos
Sistema Nervoso Central/efeitos dos fármacos , Hexobarbital/farmacologia , Animais , Relação Dose-Resposta a Droga , Eletroencefalografia , Feminino , Hexobarbital/administração & dosagem , Masculino , Camundongos , Ratos , Fatores Sexuais , Sono/efeitos dos fármacos , Fatores de Tempo
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