Methylene Blue Reduction Test Research Articles

A spectroscopy-based proof-of-concept (POC) for developing loading of pathogen analyzer (LOPA) for dairy products

Detection of bacterial contamination in dairy products of daily use is a challenge worldwide. We have utilized Methylene Blue Reduction Test (MBRT) for quantification of the microbial count in dairy products (milk) and developed a proof-of-concept (POC) based on this for in-filed applications. In this study, we have used pasteurized milk contaminated with model bacteria Escherichia coli, and Staphylococcus aureus for the calibration and validation of the developed POC. The conversion of MB to Leuco-MB i.e., the colorimetric change due to the reduction of MB to Leuco-MB in presence of microbes has been utilized as the tool to detect presence of microbes in milk. The absorbance peak for methylene blue (MB) at 664 nm decreases significantly in presence of microbes and the blue color becomes faded. In our study, we have employed methylene blue (MB) discolouration phenomenon to estimate the microbial count in milk samples using our developed spectroscopy based POC. The limit of detection (LOD) and the limit of quantitation (LOQ) of the POC were found to be 0.32 CFU/mL and 0.97 CFU/mL. The end users of the developed POC are primarily those involved in the production, processing, testing, regulation, and research of dairy products to ensure they meet safety standards and protect public health. These include retailers, dairy farmers, dairy processors, quality control laboratories, regulatory agencies and research institutions. In our experiment, we have observed a significant change in MB absorption in the milk contaminated with microbes. The indigenously developed sensor strips designed for the working of the POC turn to colorless Leuco-MB compared to milk without the microbes. The analysis of the strips has been measured in the developed device.

A mixture of free and microencapsulated essential oils combined with turmeric and tannin in the diet of cattle in the growing and finishing phase: A new tool to enhance productivity

The study was conducted to evaluate whether adding a blend containing free and microencapsulated essential oils, combined with turmeric and tannin, can replace monensin as a performance improver, positively influencing animal health and meat quality. Fourteen male cattle with an average initial body weight of 253 kg and ten females with an average initial body weight of 239 kg were included in the experiment in a confinement system. The animals were divided into four independent groups: Males (M-PHYTO, inclusion of the phytogenic mixture; M-MONEN, inclusion of monensin); Females (F-PHYTO, inclusion of phytogenic; F-MONEN, inclusion of monensin). The diets were formulated for an average daily gain of 1.5 kg, with food provided twice daily. Data and biological samples were collected on days 33, 100, and 153. M-PHYTO and F-PHYTO showed greater average daily gain and body weight, with a tendency to consume more dry matter and feed efficiency. However, the apparent digestibility of nutrients was higher in animals in the MONEN group than those in the PHYTO group, regardless of sex. The total number of leukocytes in cattle in the M-PHYTO and F-PHYTO groups was higher due to the higher lymphocyte count in the blood of these animals. The activity of gamma-glutamyltransferase and aspartate aminotransferase in animals that consumed the phytogenic mixture was lower compared to animals that consumed monensin. TBARS levels were lower in the serum and meat of cattle in the M-PHYTO and F-PHYTO groups, as were the total thiol concentration and glutathione S-transferase activity in the blood and meat of these animals. Bacterial activity was greater in the rumen fluid of cattle that consumed the phytogenic, as demonstrated by the methylene blue reduction test. The total production of short-chain fatty acids and acetic acid showed an interaction between treatment and days for both sex classes and an effect of treatment for females, with a higher concentration in the rumen in the M-PHYTO and F-PHYTO groups. Propionic acid affected treatment and the treatment x day interaction for males and females, with the M-PHYTO and F-PHYTO groups showing higher concentrations. There was an interaction between treatment and day in the acetate/propionate ratio, being lower in M-PHYTO and F-PHYTO cattle. Treatment between ruminal microbiota groups had no effect. The rib eye area had more significant gains when consumed phytogenic by males and females. The subcutaneous and sirloin fat thickness was greater in F-PHYTO animals than in the control group; however, in males, the result was the opposite. The sum of polyunsaturated fatty acids in meat was higher in M-PHYTO compared to M-MONEN and lower in F-PHYTO meat compared to F-MONEN. These results indicate that the phytogenic mixture is a potential performance improver in the diet of growing and finishing cattle, regardless of sex, but meat characteristics differ between males and females.

Evaluation of Three (3) Techniques in the Diagnosis of Subclinical Mastitis with Antibiotic Resistance of S. aureus in Nigeria

Abstract This study was aimed at evaluation of two diagnostic techniques and the cultural isolation of Staphylococcus aureus for the testing of subclinical mastitis in lactating cows. A total of 144 milk samples from 36 cows were examined. Ten (10) ml milk samples were aseptically collected from each quarter into labelled sterile universal bottles. The California Mastitis Test (CMT) and the Methylene Blue Reduction Test (MBRT) were carried out on each sample, before cultural isolation (gold standard test) was conducted. Forty eight milk samples were CMT-positive and 60 samples were MBRT-positive, while the gold standard (S. aureus isolation) had 31 positives. The 89.5 % samples of CMT-positive were correctly identified by the test culture. The proportions of samples that tested negative for Subclinical Mastitis (SCM) that did not have the disease, which is a negative predictive value, are 97.9 % and 92.9 % for CMT and MBRT, respectively. The highest total resistance of S. aureus to antibiotics was detected for gentamycin and chloramphenicol (100 %), followed by streptomycin and amoxicillin at 80.6 % and 74.1 %, respectively. The control and monitoring of subclinical mastitis in lactating cows are of great importance to human health. A good management system constitutes the priority in controlling subclinical mastitis in lactating cows.

Determination of the Presence, Concentration, and effects of Formalin on Raw milk around Nyeri Municipality

Milk adulteration is done to increase the milk quantity or its shelf life. This research focused on the latter, accomplished by adding chemicals such as formalin. This is a great global concern and it causes detrimental effects such as cancer, myeloid leukemia. The chemical effects of formalin on milk include reducing its pH, protein, and fat percentage. Five samples were collected from several milk vendors around Nyeri Municipality and a sample directly from the cow. The pure milk had the fastest reduction time (18.3±1.53minutes) in Methylene Blue Reduction Test. The milk samples had an average of 3.3929±2.0579ppm formalin. In UV-Vis, the LOD and LOQ, R2 were 0.001M and 0.004M, 0.9868 respectively. Both the butter fat, and pH values decreased with formalin concentration increase. Their mean was 3.1±0.4% and 5.47 ± 0.806 respectively. Out of the six samples, 83.33% of them were adultered with formalin.

Nutrient intake, digestibility and ruminal characteristics of lambs supplemented with probiotic

The aim of this study was to evaluate the inclusion of different levels of probiotic in the diets of lambs, on ruminal characteristics, intake and digestibility of nutrients. The treatments were 0 (control group), 2, 4 and 6g/day of probiotic doses, supplied orally and individually to the lambs. Four crossbred Santa Inês X Texel lambs were used, and the experimental design was a Latin square, with four treatments and four periods. Samples of diet, orts, feces, and ruminal fluid were collected from each animal. Intake and apparent digestibility variables were not different (p > 0.05) among the levels of probiotic evaluated. The average daily feed intake of lambs ranged from 1.27 to 1.28kg of DM/day, and no significant differences (p > 0.05) were obtained between the levels of probiotics used in the diet. The percentage distribution of protozoa was not significant according to the different doses of probiotics used. A positive linear effect was obtained between the pH of the rumen fluid and the probiotic used, indicating that the highest pH values were obtained when the animals received the higher dose of 6g probiotic; indicative that its use provides a ruminal environment closer to neutrality. The methylene blue reduction test in ruminal fluid samples did not differ between the different doses of probiotics used. The increasing levels of the probiotic in the diet of lambs are related to an increase in ruminal pH, without changing the levels of intake and digestibility of nutrients.

To Detect the Adulteration of Raw Milk by Color Test in the Laboratory as to Safe Guard the Human Health

Background: Milk is important part of diet due to its nutritive values. It is recommended for population of every age group.Milk is required for the growth and maintenance of health. When consumers buy milk they have a right toassume that milk will be pure and unadulterated. It is the duty of the milk vendors to provide unadulterated milk to the consumers. Adulteration is the act of addition of substances to a product that makes it unfit for human consumption. These additives are used to make the product cheaper and increase its amount.1Material and Method: A prospective study was conducted by Central Research Laboratory of Muzaffarnagar Medical College, to find out the adulteration of raw buffalo milk sampleobtained from rural areas around Muzaffarnagar Medical College,by color test methodology. The Institutional ethical committee permission was taken.100 samples were collected from 30 different villages around Muzaffarnagar Medical College. The raw milk sample was analyzed for physical appearance, pH, quality,dilution and presence of adulterant by color test.Result: It was observed that out of 100 samples, 85% samples were white and 15% samples were slightly yellow. The pH of the raw milk samples ranged from 6.5-7.0. The Methylene Blue Reduction Test (MBRT) showed 10samples of raw milk were of poor quality, 15 raw milk samples were fair quality, 45 raw milk samples were good quality and 30 raw milk samples were of very good quality.Result: In our study water and table sugar were the common adulterants and Benzoic acid was present in traces. So it was concluded that the raw buffalo milk obtained from the near by rural area around Muzaffarnagar Medical College was comparatively of good quality. The common adulterants obtained from raw milk of buffalo were water and table sugar. These malpractices by local dairy owner should be checked to ensure good quality of milk to the consumers.

Performance Analysis of the Milk Pasteurization Process Using a Flat Plate Solar Collector

A large share of Ethiopia’s milk production comes from its rural areas. However, this milk does not undergo further processing into dairy products on a large scale due to lack of conventional energy sources such as electricity and gas. Hence, the country is not utilizing its milk resources to the maximum possible. In this study, the possible use of solar energy for the milk pasteurization process is investigated by using a flat plate solar collector (FPSC) with and without reflectors integrated. Reflectors added to the FPSC have augmented the incident solar radiation on the collector from 0.27–0.91 kW/m2 to 0.36–1.18 kW/m2. The thermal efficiency obtained for the FPSC with reflectors integrated is 51.8% whereas that of the collector without reflectors integrated is 46.2%. Likewise, the exergy efficiency is found to be 5.43% for the collector integrated with reflectors and 2.53% for the collector without reflectors. Also, an increase in the daily processed milk production of 18% is observed in September and 16% in November by using the solar collector with reflectors integrated. The quality of pasteurized milk is checked by using the methylene blue reduction test (MBRT) method, and it indicates a better quality of pasteurized milk when compared with raw milk. Therefore, this study shows that the use of solar energy for milk pasteurization has great potential to increase the shelf life of milk, and it can be used as an instrument to improve the quality of life of people living in rural areas.

Methods to differentiate between cotton tract area ghee and cotton seed oil adulterated ghee.

Ghee, the clarified butter fat is one of the principal dairy products in India. In some places of India, cotton seed is fed extensively to dairy animals which changes the physico-chemical constants and fatty acid profile of the milk fat. Ghee is often adulterated with cotton seed oil and is marketed as cotton tract area ghee. Physico-chemical constants like RM value, Polenske value, BR reading, saponification value, iodine value and colorimetric tests i.e., Halphen and DPPH radical test were employed to differentiate ghee adulterated with cotton seed oil and that from cotton tract area. Chromatographic techniques like HPLC and GC-MS were also explored. Physico-chemical constants were not useful to differentiate the two types of ghee. Cyclopropenoic acids were observed only in ghee adulterated with cotton seed oil and not in cotton tract ghee. The RP-HPLC could able to distinguish the cotton tract area ghee from ghee adulterated with cotton seed oil on the basis of presence of β-sitosterol in the latter. Halphen test was positive for cotton tract ghee, but not for the cotton seed oil adulterated ghee. Methylene blue reduction and DPPH radical test were also found to be useful to distinguish both types of ghee.

CONCORDANCE OF METHYLENE BLUE REDUCTION AND MICROBIOLOGICAL TECHNIQUES IN THE ANALYSIS OF RAW AND PROCESSED MILK QUALITY: A COMPARATIVE STUDY

Raw milk is a milk that has not undergone pasteurization for an effective pathogen elimination, thus having a reduced shelf life due to microbial activities. Microorganisms such as bacteria can affect the quality of diary products, hence the need to assess the microbial quality of natural cow milk, pasteurized milk and processed tin-milk which are consumed on daily basis in Nigeria, Africa and the world at large. In this study, raw (unpasteurized) and processed milk samples from two locations (Bogobiri and Watt market) in Calabar municipal were analyzed using methylene blue reduction test (MBRT), total heterotrophic bacterial count (THBC) and total coliform count (TCC). The total Heterotrophic bacterial count ranged from too numerous to count (TNTC) to 3.86 x 106 colony forming unit (CFU)/milliliter (ml) in samples MA (Unpasteurized/Raw cow milk) and MB (Pasteurized cow milk) respectively. There was no fungal growth in five of the samples except MA that had a fungal count that was TNTC. The highest TCC was obtained from sample MA, with a value of 2.96 x 106 CFU/mL while sample MD had the lowest count of one colony. The total microbial count from sample MA was extremely high and above the standard signifying that it is unfit for human consumption. The MBRT result revealed that MD (Processed liquid tin-milk) and MC (Processed liquid tin-milk) gave no methylene blue reduction (excellent quality) while MB (Pasteurized cow milk), ME (Processed liquid tin-milk) and MF (Processed liquid tin-milk) were of fair quality. However, MA gave a poor quality based on the MBR time of between 30 m to 2 h corroborating with the high value of its THBC which was above the standard. Milk being a vital protein source and an excellent medium for microbial growth should be thoroughly treated by sterilization in a bottle as the study revealed that the milk microbial load can be greatly reduced by pasteurization, with sterilization in bottle having a greater bactericidal effect than pasteurization.

Serological identification, virulence factors, antibiogram and plasmid profile of Escherichia coli serotypes in raw milk and pasteurized milk products

Milk is an excellent medium that supports microbial growth with resultant spoilage of the products. Thus, this study determined the antibiogram, presumptive location of antibiotic resistance markers (ARM), and plasmid DNA molecular weight of pathogenic Escherichia coli serotypes in raw milk (n = 76) and pasteurized milk products (n = 77). Quality of raw milk and pasteurized milk products was evaluated using Methylene Blue Reduction Test (MBRT). Occurrence of E. coli in the samples was determined by Cefixime tellurite-sorbitol MacConkey agar and latex agglutination kits. The virulence factors, antibiotic susceptibility, location of ARM, and plasmid DNA molecular weight of E. coli serotypes were assayed using bacteriological media, disc diffusion, acridine orange and agarose gel electrophoresis, respectively. Based on the MBRT, 2.6% samples were graded as excellent, 9.8% samples were of good quality, while 22.2% samples were of a very poor quality as decolourization of methylene blue occurred in ˂ 20 min. E. coli 0157 and E. coli 0145 had the highest and lowest percentage of occurrence, respectively; ≤ 29 E. coli serotypes were caseinase, amylase and lecithinase producers. E. coli serotypes were highly sensitive to Ciprofloxacin and Gentamycin with percentage sensitivity ranging from 74.6 % to 81.4 %; ≤ 50.0 % E. coli 0125 were sensitive to Ofloxacin; between 33.3 % and 50.0 % E. coli 0103 were resistant to Nalidixic Acid and Ofloxacin; ≥ 53.7 % E. coli serotypes were multi-drug resistant; 19.0 % had their entire ARM located on the plasmids, while 50.0 % had their ARM residing both on the plasmids and chromosomes with plasmids sizes ranging from 0.54 kb to 43.5 kb. The occurrences of pathogenic E. coli in the milk samples indicated the need to enlighten milkers on the hygienic practices to adopt during milking and as well showed that post-pasteurization contamination of milk products should be avoided.

Clinical, haemato-biochemical, and ultrasonographic findings of abomasal impaction and abomasal ulcers in buffaloes

The current study evaluated the clinical, ruminal, haemato-biochemical, and ultrasonographic findings of abomasal disorders' affected buffaloes grouped as abomasal impaction (n = 18) and abomasal ulcers (n = 15). The abomasal disorders' screening was based on clinical examination and confirmed by ultrasonography. The most common clinical findings of the buffaloes affected with abomasal disorders include depressed demeanour (96.97%), absence of rumination (87.88%), abdominal guarding (87.88%), sunken eye balls (81.82%), tachycardia (78.79%), tachypnea (72.73%), and kyphosis (63.64%). The average rumen motility, respiratory rate, and pulse rate for abomasal impaction and abomasal ulcers were 0.28, 33.37, and 83.44, and 0.33, 35.87, and 92.60, respectively. The faecal occult blood test (benzidine test) revealed the presence of melena in all the buffaloes diagnosed with abomasal ulcers (100%). The ultrasonographic examination of the abomasal impaction group revealed increased abomasal size with no movement of the abomasal contents. The ultrasonographic imaging of abomasal ulcer-affected buffaloes showed irregularity in the abomasal wall-outline with moderately echogenic abomasal contents and a layer of fibrin at the affected area. Nine buffaloes had ultrasonographic evidence of peritonitis. The abomasal contents of buffaloes with positive benzidine test (n = 15) were screened for Clostridium perfringens by a polymerase chain reaction and were found positive for cpa toxin yielding 900-bp length. The rumen protozoal count was higher in healthy buffaloes, while the sedimentation test, (time) methylene blue reduction test, (time) and chloride levels were higher (P < 0.01) in the buffaloes affected with abomasal disorders. Haematological findings revealed a higher haematocrit, total leucocyte count, neutrophils, and eosinophil proportion and lower haemoglobin, total erythrocyte count, and lymphocyte proportion without affecting the fractions of monocytes and basophils. Furthermore, the buffaloes affected with abomasal disorders showed lower albumin, phosphorus, and potassium and higher aspartate transaminase, blood urea nitrogen, creatinine kinase, creatinine, and chloride concentrations. The present study projects clinical signs, ruminal parameters, and haemato-biochemical parameters as better indicators of abomasal disorders; however, ultrasonography is the sole diagnostic aid for the confirmation of abomasal disorders in buffaloes.

Treated Cow Milk Quality Analysis in High-Temperature Short Time (HTST) Thermal Treatment using F-Value and Methylene Blue Reduction Test (MBRT)

This study was conducted to evaluate raw and pasteurized cow milk regarding physical properties, microbiological quality, and lethality value ofMycobacterium Paratuberculosis(MAP)at different temperature and time combinations of the pasteurization process.Cow milk samples were pasteurized at high-temperature (70°C, 75°C, and 81°C) and short-time (15s and 25s) high temperature and short time (HTST) combinations. Raw and pasteurized (HTST) cow milk was analyzed, while commercial cow milk that undergo proses (HTST) was used as control. High-temperature short time (HTST) pasteurization showed a significant effect on the colour of raw and pasteurized cow milk (p&lt;0.05) at every temperature. In addition, cow milk also indicated an increase in lightness and yellowness after HTST pasteurization.The microbiological quality of raw, pasteurized, and commercial cow milk is evaluated using the Methylene Blue Reduction (MBRT) test, a common, rapid, simple, and inexpensive method for microbiological quality evaluation.The MBRT on raw milk samples revealed that it was of poor quality. On the other hand, all pasteurized samples were good quality, and the commercial sample was excellent.Based on the evaluated F-values, the most suitable temperature and time combinationsin this study was 70°C and 25s.

Tradition of raw milk consumption and its health impact among people living in the coastal regions of Bangladesh

Milk is a nutrient-rich liquid food for human and animals. However, owing to its complex biochemical structure and high water activity, it serves as an outstanding microorganism growth medium under suitable conditions. People in Bangladesh's coastal areas have a lifestyle and tradition that includes drinking raw milk for nutrition or as an energy drink, which presents a health risk to them. The present cross-sectional study was carried out to determine the reasons for drinking raw milk in coastal areas, as well as the public health impact of doing so. A total of 100 respondents were interviewed and subsequently, milk samples were collected for quality testing through methylene blue reduction test (MBRT). Among 100 respondent 70 were consumers and 30 were farmers. Results showed that the samples of farmers were better than that of consumers. The majority of raw milk consumers were male who thought raw milk was more nutritious than heat-treated milk. Furthermore, the majority of them were professionally engaged in farming. Both consumers and farmers had less educational qualifications, managed their cattle in dirty environments, practiced extensive grazing system on communal grazing areas and around one fourth of them vaccinated their animals. Furthermore, the findings revealed that 40% of respondents were between the ages of 35 and 45, with 62% reporting no health complications as a result of drinking raw milk and the remainder reporting mainly gastrointestinal problems. According to the findings of this report, the quality of raw cow milk was poor; unhygienic practices and poor animal husbandry at farm level predisposed farmers, consumers and the public to risk of contracting milk-borne infections and associated bacterial resistances. It is recommended that veterinarians, extension officers and all stakeholders should play their roles in ensuring safe quality milk supply to consumers.&#x0D; Asian Australas. J. Biosci. Biotechnol. 2021, 6 (1), 10-18

Bacteriological quality of raw milk marketed in and around Guwahati city, Assam, India.

Background and Aim:Milk is a highly perishable commodity, which is subjected to various types of contamination right from the farm level to the consumers’ table. This study aimed to assess the quality of raw milk sold in and around Guwahati city based on the microbial load.Materials and Methods:A total of 200 raw pooled milk samples collected from 25 different locations in and around Guwahati city were subjected to quality evaluation based on the methylene blue reduction test (MBRT), standard plate count, and coliform count as per the standard procedure.Results:Out of the 200 samples evaluated, more than 50% of them were graded as poor to very poor quality based on the MBRT results. None of the samples could be graded as excellent quality and only 14.5% were graded as good quality. The standard plate count and coliform count of all the raw milk samples were found to be significantly higher than the legal standard. A highly significant (p<0.01) difference was observed for standard plate count and coliform count among the different locations in and around Guwahati city.Conclusion:From the present study, it could be inferred that raw milk sold in most parts of Guwahati city do not confer to the legal microbiological standard and may pose a high risk of milk-borne illness among consumers of the city, which needs a systematic series of actions to be implemented properly.

COMPOSITION AND QUALITY OF FRESH COW MILK OFFERED FOR SALE IN PARTS OF PLATEAU STATE OF NIGERIA.

The gross composition and quality of fresh cow milk purchased from Fulani milk vendors in three locations of Plateau State were investigated. Milk quality was assessed by the methylene blue reduction test while bacterial contamination was by the agar plate count and the direct microscopic count. The mean contents of total solids, butterfat, protein and ash of a total of 100 samples from Barkin Ladi, Jos and Bukuru markets were 12.45, 4.77, 3.90, 0.92; 12.85, 4.50, 3.68, 0.93; and 12.41, 5.26, 3.72, 0.91% respectively. The proximate constituents did not differ significantly between locations. The methylene blue test indicated that only 23.5% of the sample were of good quality while 41.2 and 35.3% were rated fair and poor respectively. No sample merited excellent rating. The agar plate count showed a range of 1.97 x 106 for Bukuru to 2.54 x 106 cells/ml for Jos market. The direct microscopic count showed the highest mean bacteria value for Barkin Ladi samples. The high bacterial counts as observed were probably indicative of poor milking hygiene and handling. It is suggested that such milk should be properly pasteurized before consumption and delivered/marketed early at source to reduce the time for microbial multiplication.

Computer vision based Comparative Studies on the Physicochemical Analysis and Bacterial Biota in Different Milk Samples

Milk is a complete food with high nutritional value. Milk is an important culture medium for the growth and reproduction of microorganisms. This study focuses on the samples collected from the different milk distribution areas in MaduranthagamTaluk, South India. Fifty pasteurized milk samples of ten different brands were collected and physicochemical, microbiological analysis were carried out in both raw milk and pasteurized milk samples. The milk samples were subjected to physicochemical analysis such as Fat content, Clearance, Lactometric Reading, Clot on Boiling Test, Solid Non Fat and Acidity were calculated. The milk sample were also subjected to the chemical analysis for the Nitrogen content, crude protein content, Lactose content, ash content were also calculated Methylene blue reduction test has been used to test quality of the milk samples. These findings may be helpful to monitor the quality of the milk products in the market. It can provide an interest in examine the organic and inorganic content in milk. It is reported that all samples added with urea and few samples have sulphate. Raw milk showed inferior quality, processed milk have Low load of bacterial population.

Detection of lactoferrin in bovine and goat milk by enzyme-linked immunosorbent assay

Lactoferrin (LF) has been proposed as a multifaceted functional ingredient of food. A competitive enzyme-linked immunosorbent assay (ELISA) was established to determine the LF in milk by using bovine LF antiserum and bovine LF-Biotin conjugate. The LF concentration in cow milk samples could be determined by this ELISA. However, the LF concentration in goat milk could not be measured using this method. Thus, the goat LF ELISA was established using goat LF-Biotin conjugate to measure the LF concentration in goat milk. Milk samples were collected for measurement of their LF concentrations. The mean LF level for the individual cow milk samples with the somatic cell count (SCC) below 1 × 105, 1 to 2.5 × 105 or 2.5 × 105 to 5 × 105 cells/mL was found to be about 176, 466 or 742 μg/mL, respectively. On the other hand, the LF level was about 200 μg/mL in goat bulk milks with the methylene blue reduction test (MBRT) time more than 5 hr. In conclusion, both LF ELISA methods developed in this study could be successfully used to determine the LF concentration in goat and cow milk.

Observações clínicas, hematologia e características do fluido ruminal de bovinos de corte recebendo dieta "Max Beef" grão inteiro

Este estudo propôs caracterizar os efeitos da alimentação baseada na dieta do grão de milho inteiro na dinâmica de parâmetros clínicos e metabólitos bioquímicos de bovinos confinados. Foram utilizados 20 bovinos, sem raça definida, adultos, com peso médio de 300 kg, divididos em dois grupos experimentais. O grupo experimental (G1; n=15), composto por animais alimentado somente dieta “Max Beef” Grão Inteiro e o grupo controle (G2; n=5), composto por animais, alimentado com bagaço de cana e a dieta “Max Beef” Grão Inteiro, na proporção 30:70. Todos os animais foram submetidos às observações clínicas, colheita de sangue por venopunção jugular e fluido ruminal. Os animais do grupo G1 (Dieta “Max Beef” Grão Inteiro) apresentaram movimentos ruminais incompletos, timpania ruminal branda e diarreia com grãos de milho inteiro. Não foram registradas alterações hematológicas nem na concentração de fibrinogênio. Apresentaram menor valor de pH ruminal durante todo o período experimental, com comprometimento da população de infusórios, diminuição da prova de redução do azul de metileno e tempo de sedimentação e flotação ausente. Conclui-se que dietas para bovinos de corte contendo “Max Beef” Grão Inteiro provoca acidose crônica ruminal e compromete as características físico-químicas e microbiológicas do fluido ruminal.

Study on Physico-Chemical and Microbial Quality of Raw Milk Collected From Different Places of Assi Region in Varanasi City, Varanasi

The present study was conducted to evaluate the physico-chemical characteristics including Adulteration and Microbiological quality of cow raw milk collected from four different places of ASSI region in Varanasi. Samples were analysed to know the chemical composition, the results showed that the statistically average percentage of Moisture (87.46), Fat (3.87), Protein (3.15), Lactose (4.42), Ash (.712), pH (6.43) and acidity (0.147). The keeping quality of milk was evaluated by Methylene Blue Reduction Test (MBRT). This phenomenon testified that milk sample 1 is fair quality and remained sample were found good and excellent. The microbiological conclusion confirmed the presence (less or more) of microbial load in all the raw milk samples. The highest level of microbial quality in standard plate count (SPC) was 19.1×106 cfu/ml. in sample 1 and in logarithm value is 7.28 cfu/ml at the same time, the highest coliform bacteria 2.3×102 in logarithm value is 2.36 was found in the sample 2. The adulterations in raw milk were checked by the standard procedure. In cow’s raw milk the different mixed adulterant were found in two samples contaminated with detergent and pulverized soap. Besides different hazardous chemical adulterant, raw milk from sample 1 was detected with presence of hydrogen peroxide and sample 2 was contaminated formalin whereas urea was present in sample 2 and 4. Milk adulteration is a global concern and social problem. Increased demand, growth in competition in dairy industry and financial gain makes some producers to adulterate the milk thereby decreasing milk quality.

The extended methylene blue reduction test and milk quality

Introduction. This study aimed to evaluate the quality of milk produced by six cattlemen’s associations in small, isolated farming communities of Carchi, Ecuador. It involved a herd of 814 cows and lasted eight consecutive months. Another aim was to propose a suitable methodology for milk quality evaluation.&#x0D; Study objects and methods. All milk samples were analyzed for total solids, protein, fat, acidity, density, total bacterial count (TBC) and somatic cell count (SCC). Each sample was subjected to an extended qualitative methylene blue reduction test (MBRTe) for which 10 mL of milk, with 0.5 mL of methylene blue, was incubated at 37°C for 24 h. &#x0D; Results and discussion. As a result, we obtained the following types of clots: MBRTe-I (homogeneous solid/liquid clot), MBRTe-II (lumpy clot), MBRTe-III (gaseous clot) and MBRTe-IV (lumpy + gaseous clot). The study showed significant differences in the quality of milk between different associations, suggesting that some of them did not comply with good practices of milking, handling and storage of fresh milk. The quality of milk was classified as good in one association, as regular in another association, and as low in four associations. The MBRTe classified 37% of the samples as MBRTe-I, 18% as MBRTe-II, 14% as MBRTe-III and 12% as MBRTe-IV. Of the MBRTe-I samples, 95% showed the TBC and SCC values of first quality milk. The MBRTe-II had the TBC values of first quality milk, but exceeded the SCC, while the MBRTe-III had good SCC values, but exceeded the TBC. Finally, the MBRTe-IV samples exceeded the permissible levels of both TBC and SCC.&#x0D; Conclusion. It was proved that the MBRTe can help milk producers evaluate the quality of milk and alert them to the possible presence of mastitis in the herd. The MBRTe is a reliable and cheap method that is quick and easy to perform.