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The objectives of this study were to determine carbohydrates such as glucose, total protein, lipid parameters, mineral levels in blood; qualitative characteristics such as fat, SNF, lactose, total solids and protein percentages of milk; and the quantity of milk after feeding german and maize fodders. Thirty clinically and apparently healthy cows were selected and divided into three homogenous groups. Control group was fed mixed grass, another group was fed german grass and the last one was fed maize grass. Milk and blood samples were collected from the cows (n-30) before the study commenced. Again milk and blood samples were collected on day 30 and day 60. After collection, milk samples were analyzed by Milk Analyzer MIA-SLP-60 for proximate components. Serum samples were analyzed by different colorimetric techniques using a spectrophotometer (Humalyzer 3000®) and kits from Randox (Ireland). In addition, daily milk production records of cows were maintained. The study found a significant rise of SNF and solids, a highly significant increase of lactose and protein in the maize feed group (M), and a highly significant positive change of fat percentage in the german fed (G) group. The average daily milk production of the M and G group were respectively 11.39% and 6.98% higher than the control group. No significant change was found in hematological and biochemical parameters of blood. Further intensive long term investigation to establish relation between blood parameters and milk yield and milk quality should be carried out. Vol. 9, No. 3, December 2022: 313-322

This study aimed to assess the relationship between milk components and amino acid (AA) profiles among different buffalo crossbreds in Bangladesh. A total of thirty-six (36) lactating buffaloes were selected from Murrah, Nili-Ravi, and Mehsana crossbreds, and they were assigned to 03 groups, each with 12 buffaloes. The total experimental period was 10 weeks, including the initial 10 days of diet adjustment. The results from the experiment revealed that milk protein, fat, and total solids contents of Murrah crossbred was significantly (p0.05). In the case of milk amino acid contents, all the milk samples entailed a higher concentration of Glutamic acid (0.9-1.00 g/100 g of milk), whereas Cysteine had the lowest concentration (0.02-0.05 g/100 g). The most prevalent essential amino acids were Leucine, Lysine, and Phenylalanine, whereas the most prevalent non-essential amino acids were Glutamic acid, Proline, Asparagine, and Serine. Lysine, Isoleucine, Leucine, Phenylalanine, Cysteine, and Histidine concentrations differed significantly (p0.05). The highest Lysine: Methionine ratio observed in Murrah buffalo was about 3.20%, while in Mehsana and Nili-Ravi buffalo was about 2.80 and 2.50%, respectively. Thus, it was evident from the study that the raw milk components and amino acid composition vary considerably in the different lactating buffalo crossbreds. Finally, the compositional data of raw milk may create the way of sustainable use of milk from dairy buffalo crossbreds and improve food and nutrition security, particularly in developing countries.

The study was designed to envisage the changes in growth measurements and blood metabolites of crossbred dairy calves in response to calf starters feeding with different protein sources. All calves up to three days of age were kept on colostrum feeding. Then, calves were given 2.5 L of fresh whole milk for up to 10 days and 3 L of fresh whole milk for up to 56 days. Calves were fed a farm starter (control), other dietary groups starter containing mustard oil cake (MOC), soybean meal (SM), and a mixture of MOC and SM as MOCSM protein sources. Starting on day 21, all of the calves received starter feeds. On day 56, they were weaned, and the study included calves until day 70. Data were recorded on dry matter intake, growth measurements and blood nutrients profile. Calves consumed greater DM when MOC in the starter was supplied, which was 22.5% more than that of the control-fed group. Calves feeding with SM and MOCSM consumed almost similar quantities of DM at 220.87 and 224.87 g/head/day, respectively. The BWG of calves increased significantly by 5.04 and 4.06% more in the MOC-fed group than in the SM and MOCSM groups. MOC, SM, and MOCSM-fed calves had similar (p > 0.05) BLG; however, the control diet had significantly lower BLG. Blood glucose levels did not vary among the calves fed the control, MOC, SM, and MOCSM diets. Significantly higher serum albumin, urea, and BUN concentrations were found in MOC diet-fed calves than in others. Calcium and phosphorus concentration varied significantly among dietary groups and was noticeably lower in the control group compared to the other dietary groups. The results revealed that calf starters endowed with MOC as a protein source and in combination with SM were found advantageous in improving body growth and development.

The study was carried out on milk clotting activity of the crude proteolytic enzymes from different parts of papaya plant (Carica papaya). Cottage cheese was prepared using whole cow milk collected from Bangladesh Agricultural University Dairy Farm. Diluted papaya latex (4 drops in 100 ml distilled water) was added and thoroughly mixed for coagulation of milk from different parts of the papaya plant. The treatment samples were named as A: mature papaya; B: immature papaya; C: papaya tree leaf; D: lower part stem and E: upper part stem. In case of organoleptic evaluation it was observed that flavor, body and texture, finish, color, and total score were ranked non-significantly higher in cheese sample using latex from immature papaya B (93.34±0.45) than rest of the samples. In chemical analysis, significant (p [J Bangladesh Agril Univ 2021; 19(1.000): 85-90]

This study aimed to assess the relationship between milk components and amino acid (AA) profiles among different crossbred buffaloes in Bangladesh. A total of thirty-six (36) lactating buffaloes were selected from Murrah, Nili-Ravi, and Mehsana crossbreds, and 03 groups were made, each with 12 buffaloes. The total experimental period was 10 weeks, including 10 days of diet adjustment. The results revealed that milk protein and total solids contents of Murrah, Mehsana, and Nili-Ravi crossbred buffaloes showed a higher to lower trend (p 0.05). The highest Lysine: Methionine ratio observed in Murrah buffalo is about 3.20%, while in Mehsana and Nili-Ravi buffalo is about 2.80 and 2.50%, respectively. Thus, it is evident from the study that the raw milk components and amino acid composition vary considerably in the different crossbred lactating buffaloes. Finally, the compositional data of raw milk may create the way of sustainable use of milk from crossbred dairy buffaloes and improve food and nutrition security, particularly in developing countries.

This study was conducted to evaluate the influence of partial reinstatement of concentrate mixture (CM) by hydroponic maize fodder (HMF) on the performance of crossbred cow. Six Holstein-Friesian crossbred (HFX) lactating cows were selected and divided into two groups, control (n = 3) and hydroponic (n = 3). Both the control and hydroponic cows received 37.0 kg/head/day German grass (Echinochloa crus-galli). In control group, 4.0 kg CM was supplied daily to each cow and 25% of CM was replaced by HMF (6.1 kg/h/d) in the hydroponic group. The dry matter intake and body weight between control and hydroponic groups were found similar (P > 0.05). During the study period, about 21% higher (P < 0.001) milk was obtained in the hydroponic group compared to the control group. Compared to initial day of the study, average of 28 days milk yield was found 11% more in hydroponic group, whereas, milk production of control group was declined. Feed conversion efficiency was found higher (P < 0.001) in hydroponic group than that of the control group (1.25 vs. 1.63 kg DMI/kg milk yield and 0.76 vs. 0.97 kg TDNI/kg milk yield). Total solids (P < 0.001), fat (P = 0.004) and ash (P = 0.008) contents of milk were found higher in hydroponic group compared to the control group but other milk compositional parameters remains similar between two dietary groups. In conclusion, feeding of hydroponic maize fodder to HFX cows has positive impacts in boosting up the milk production, feed efficiency and milk composition. [J Bangladesh Agril Univ 2020; 18(3.000): 629-635]

Dairy calves must be fed appropriately to meet their nutritional needs, supporting optimal growth and development to achieve the recommended target age at first calving (AFC) of 24 months. Traditional restricted milk feeding practices suppress growth, contribute to negative welfare states and may result in malnutrition and immunosuppression. In this study a total of eight high yielding calves (four Holstein Friesian and four Sahiwal breed) whose average body weight was 44.8 kg and 58 kg respectively. The supplied calf starter was composed of maize crushed, rice polish, wheat bran, gram broken, mustard oil cake, vitamin mineral premix, molasses and common salt. Calf starter was supplied initially 0.25 kg/day/calf in equal halves to the experimental calves twice a day i.e. at 7.00 AM and 12.30 PM and gradually increase upto 1 kg/d/calf. Average body weight gain, wither height gain, body length gain, barrel height gain, and hip height gain in Sahiwal and Holstein Friesian calves were 65.97±1.04 Kg, 31.04±1.13 inch, 32.34±1.46 inch, 12.80±0.71 inch, 35.05±1.27 inch, and 53.61±2.41 Kg, 29.78±1.17 inch, 30.93±1.66 inch 11.78±0.66 inch, 33.44±1.41 inch respectively. Our study concluded to establish a consensus on calf feeding standards which support physiological function, facilitate weaning, support growth targets and ensure calf health and welfare is protected. Asian Australas. J. Biosci. Biotechnol. 2020, 5 (2), 60-64

The research was conducted to examine the day-to-day variation in colostrum composition at the udder quarter level. For this purpose, a total of 3 Holstein Frisian crossbred cows were selected from Bangladesh Agricultural University Dairy Farm. Colostrum samples were collected both as mixed and separately from different teats. The concentration of major colostrum constituents (fat, protein, lactose, total solids, solids-not-fat, ash, pH, specific gravity) changed significantly (p≤0.05), the levels on day 4 were found similar to those of normal milk. The highest mean value of fat, protein, total solid, SNF, ash and specific gravity in colostrum was observed on 1st post-partum day as 6.02±0.70, 14.20±0.18, 23.88±1.25, 17.94±0.42, 1.03±0.05% and 1.05±0.00, respectively and later on, decreased as postpartum days advanced. Minimum average fat, protein, total solid, SNF, and ash content in colostrum was observed on 5th postpartum days as 3.75±0.11, 3.24±0.08, 12.00±0.20, 8.27±0.16% and 0.695±0.01, respectively. But lactose percent and pH showed an increasing trend from 1 to 5 postpartum days. Minimum average lactose and pH was observed on 1st and 5th postpartum days as 2.42±0.06%; 6.03±0.04% and 4.26±0.15; 6.30±0.04, respectively. The quality of colostrum produced by udder quarters was found significantly different (p

Stress is an external event or condition that places a strain on a biological system. The animal response to stress involves the expenditure of energy to remove or reduce the impact of stress. This increases the maintenance requirements of the animal and results in loss of production. The biological response to stress is divided into acute and chronic phases, with the acute phase lasting hours to a few days, and the chronic phase lasting several days to weeks. The acute response is driven by homeostatic regulators of the nervous and endocrine systems and the chronic phase by homeorhetic regulators of the endocrine system. Both responses involve alterations in energy balance and metabolism. The thermal environment affects all animals and therefore represents the largest single stressor in animal production. Other types of stressors include housing conditions, overcrowding, social rank, disease, and toxic compounds. "Acclimation" to stress is a phenotypic response developed by the animal to an individual stressor within the environment. Acclimation is a homeorhetic process that takes several weeks to occur and occurs via homeorhetic, not homeostatic, mechanisms. It is a phenotypic change that disappears when the stress is removed. Milk yield and reproduction are extremely sensitive to stress because of the high energy and protein demands of lactation and the complexity of the reproductive process and multiple organs that are involved. Improvements in the protection of animals against stress require improved education of producers to recognize stress and methods for estimating the degree of stress on animals.

This study aimed to analyze the hemato profile of crossbred lactating cows reared at Bangladesh Agricultural University (BAU) Dairy Farm. Thirty-two (32) healthy crossbred lactating cows of Holstein-Frisian (HF), Jersey (J), Sindhi Sahiwal (SS) and Red Chittagong (RCC) were selected for the study and divided into four (04) groups. The cows were allowed to feed and manage according to dairy farm own scheduled-ration. The collected blood samples were analyzed for hematological and biochemical parameters viz. Hemoglobin (Hb), Packed cell volume (PCV), Total leukocyte count (TLC), and Total erythrocyte count (TEC) and Serum urea, Glucose, Albumin, Calcium, and Phosphorus, respectively by using an automated chemistry analyzer. The results revealed that the hematological and biochemical parameters non-significantly (p>0.05) differed between the crossbred groups. From the experiment, the higher amount of Hb (11 g/dL) and PCV (40%) was found in HF and RCC cows, respectively. The TLC was higher in SS and RCC but the TEC was recorded stable along with a slight increment in RCC. As far as the biochemical parameters are concerned, the blood urea concentration was found higher (28 mg/dL) in HF and RCC lactating cows. The same pattern was observed in the case of albumin concentration. On the contrary, the lowest value of Calcium was found in RCC but the Phosphorus concentration showed a little higher in RCC. It can be concluded that the overall herd health was satisfactory based on the blood profile parameters. Bang. J. Anim. Sci. 2019. 48 (2): 139-144

A study was conducted to observe the existing feeding practices, nutritional supply and production performance of the lactating buffaloes in some selected agro-climatic zones of Bangladesh, viz. Bhola (AEZ-18, Coastal area), Mymensingh (AEZ-22, River basin area) and Dinajpur (AEZ-27, Drought area). Data on availability, amount and types of feeds and fodders fed to the lactating buffaloes, body weight, milk yield and quality and lactation length were collected from 30 farmers of the each selected locations. In this investigation, the mostly used feed ingredients found were rice straw, locally available green grasses, wheat bran, broken maize, mustard oil cake and broken rice. Total feed supply (DM kg/h/d) to lactating buffaloes were 17.4, 14.5 and 13.0 in coastal, river basin and drought areas, respectively, (p>0.05). But significantly (p = 0.000) different amount (DM kg/h/d) of concentrate were supplied in coastal (1.5), river basin (1.8) and drought (2.7) areas. The highest amount (kg/h/d) of green grass was supplied in coastal area (5.0) followed by river basin area (4.3) and drought area (1.3). Accordingly, amount (kg/d) of DCP and TDN were supplied was higher in coastal area (0.365 and 6.417, respectively) than that of the river basin and drought areas (0.247-0.248 and 5.501-5.891, respectively), which were below their requirements. Significantly (p=0.000) larger lactating buffaloes were found in the river basin and drought areas (weighed 372–380 kg/h) than that of coastal area (242 kg/h). The average daily milk yield was found significantly highest (p=0.000) in the drought area (5.3 L/d) which was 1.4 L and 3.1L more than that of the river basin and coastal area, respectively. The 4% FCM yield was found two times more (p=0.000) in drought area (7.7 kg/d) than that of the coastal (3.1 kg/d) and river basin (3.6 kg/d) area. On the other hand, the significantly (p=0.000) highest lactation length and lactation yield were 294 d and 1085 L, in the river basin area, which were 189 d and 1007 L in drought area and 197d and 429 L in coastal area, respectively. Among the milk constituents, protein, ash and lactose content was found higher in drought area than that of the other two areas (p=0.001). In conclusion, the prevailing variations are evidently considerable. Therefore, suggesting further works for large scale baseline data regarding buffalo populations, nutritive quality of feeds and fodder, effectiveness of existing management tools and adoption of new technologies. Bang. J. Anim. Sci. 2019. 48 (2): 127-138

The study was aimed at assessing the productive performance of dairy buffalo and milk marketing approaches in different agro-climatic districts of Bangladesh. Three (03) districts of Bangladesh viz. Bhola, Mymensingh, and Dinajpur were chosen from the coastal, river basin and semi-arid region, respectively. A triangulation method of survey was used to collect the data and the components of the triangle were buffalo farms, buffalo farmers and buffalo herdsmen. The investigation duration was twelve (12) months. The study revealed that the highest milk yield (5 L/h/d; p=0.010) was found in the river basin and semi-arid region. Lactation yield was also recorded double in the river basin and semi-arid districts compared to coastal districts (p=0.000). In the case of lactation length, the river basin buffaloes possessed 33 and 36% longer than coastal and semi-arid districts, respectively. All the chemical components were found significantly different (p≤0.050) but fat. Among different agro-climatic districts, about 92% of milk was traded in the coastal region after meeting the household's need but it was noted that the farmers from the semi-arid region kept more than 21% of milk for family consumption (p=0.000). The highest unit price (BDT 72/L) of milk was observed in the river basin district (p=0.011). In conclusion, the current situations of buffalo farming and milk marketing approaches in Bangladesh, varies considerably.

The aim of this research was evaluation of dahi prepared from cow and buffalo skim milk addition of mango juice. Four types of dahi were prepared from cow’s and buffalo’s skim milk which designated by A (cows skim milk), B (cows skim milk with 10% mango juice), C (buffalo’s skim milk) and D (buffalo’s skim milk with 10% mango juice). The quality of prepared dahi was measured by organoleptic, chemical and microbiological test. Smell and taste, body and consistency, colour and texture score of dahi improved due to adding mango juice to compare with their control group. The overall acceptability score of B and D sample were 85.67±1.53 and 81.67±4.04 which higher than both control group. From chemical analysis, it was found higher total solids in 10% mango juice containing B (202.0±0.20 g/kg) and D (196.0±0.49 g/kg) dahi samples than both control groups. Again, lower fat and protein contents found in 10% mango juice containing B and D dahi samples. Total viable count was found significantly higher in both 10% mango juice containing B and D dahi samples than both control groups. In conclusion, that addition of mango juice with cow’s skim milk dahi or buffalo skim milk dahi were both better in terms of organoleptic and chemical qualities more acceptable than plain skim milk dahi.Asian J. Med. Biol. Res. June 2017, 3(2): 191-197

The study was aimed to develop a probiotic beverage using Chhana whey and watermelon juice. The blends of whey and watermelon juice were optimized based on physicochemical and sensory evaluation. The bacterial culture was used as per 1% Lactobacillus acidophilus NIAI L-54 as a probiotic culture. The 75:25 blend of whey and watermelon fermented for 5 h at 37 oC obtained the highest sensory scores for overall acceptability. The shelf-life of the selected blend was examined using titratable acidity, pH, microbiological analysis as well as sensory evaluation. The results suggested that probiotic beverages can be preserved for 21 days in refrigerated conditions (4 oC) with higher acceptability along with probiotic bacterial count 4.00 Log10CFU /mL. It could be concluded that the whey-based watermelon beverage enabled by-product utilization with excellent nutritional and functional value.

A study was carried out to investigate the effect of different coagulants on the recovery of milk solids, yield and sensory quality of Chhana and the resultant Rasogolla. Six type of coagulants comprising of sour whey (0.5%, 1.0% acidity), citric acid (0.5%, 1.0% acidity) and blend of sour whey and citric acid (0.5%, 1.0% acidity) were used to prepare Chhana followed by sweet meat Rasogolla. The nonsignificant yield of chhana was found by the use of different coagulants; however it had a significant influence on the fat and total solids (TS) recoveries ranges from 90.5 to 93.8%; 42 to 44% of milk for chhana, respectively. The highest mean yield, fat recovery and TS recovery were recorded for B type chhana prepared using 1% sour whey as coagulant. Rasogollas prepared using varying coagulants did not have any significant influence on any of the sensory attributes of product studied. Rasogolla prepared from chhana made using 1% sour whey as coagulant had the highest overall sensory score. It is recommended to employ sour whey with 1.0 % of titratable acidity as coagulating agent in the preparation of Rasogolla.

This study was undertaken to envisage the effect of milk preservation by food grade hydrogen peroxide (H2O2) on sensory and physicochemical properties of doi and rosogolla prepared from that preserved milk. Cow milk was collected from the Bangladesh Agricultural University (BAU) Dairy Farm. H2O2 was diluted at the ratio of 1:2.5 (H2O2: distilled water) before mixing with milk to reduce the concentration of H2O2 from 35% to 10%. Later on 0.14% (by volume of milk) H2O2 was added to milk samples and preserved to 18 h. The preserved milk samples were then used to manufacture doi (PMD) and rosogolla (PMR). Doi (FMD) and rosogolla (FMR) were also prepared from fresh cow milk without adding H2O2. Sensory properties and proximate composition of both FMD and PMD were found non-significantly (p>0.05) different. Similar results were also found in the case of FMR and PMR. Acidity (%) of both types of products was found 0.05% higher in the fresh milk products. It may be concluded that 0.14% H2O2 treated milk is suitable to manufacture quality doi and rosogolla without any inimical effect on the sensory and physicochemical properties. [J Bangladesh Agril Univ 2021; 19(4.000): 533-541]

This experiment was conducted to evaluate the quality of existing ultra-high temperature (UHT) treated milk available in two selected town markets of Bangladesh. A total of 27 UHT milk samples from three different brands–Pran Dairy (A), Aarong Dairy (B) and Farm Fresh (C) were collected from local markets at Mymensingh and Gazipur districts during the period of 1stSeptember to 29th November, 2014. Parameters studied in this experiment were organoleptic (flavour, consistency, colour and appearance), physic-chemical (specific gravity, acidity, total solids, solids-not-fat, fat, protein, lactose, and ash) and microbiological (Total Viable Count and Coliform Count). All the samples were similar in respect of color, flavor, taste and texture, and no significant difference was observed. However, significant differences were revealed (p0.05) in case of fat, lactose, and ash content. Total Viable Count and Coliform count were found to be nil in all the milk samples. Milk samples of Farm Fresh UHT milk were superior to other brands of UHT Milk in terms of contents of total solids (119.23±0.57 g/kg),fat (34.97±0.35g/kg), lactose (43.23±0.51g/kg), and ash (7.00±0.26g/kg). Though there were some fluctuations in all the parameters studied, all the milk samples conformed to the standard values for UHT milk, and in general all of the UHT milk samples studied in this experiment was of good quality.Bang. J. Anim. Sci. 2015. 44 (3):132-136

The present study was conducted to investigate the feasibility of using coconut milk by replacing reconstituted skim milk for Dahi manufacturing. Reconstituted skimmed milk was replaced by 0, 10, 20, and 30% coconut milk to produce Dahi designated as A, B, C and D. All the samples were analyzed for organoleptic, chemical and microbiological qualities. According to organoleptic test, the overall highest score was observed in sample B (84.37±1.64) and the lowest score was found in sample D (75.0±1.41). In all levels of replacement increased fat, carbohydrates, ash and total solids were obtained, while moisture and protein content were significantly decreased in Dahi samples. Acidity and pH of all the treatments were significantly influenced and ranged from 0.65 to 0.73% and 4.21 to 4.57, respectively. Ash content of all samples was not significantly increased. Total viable count of reconstituted Dahi samples (B, C and D) was significantly increased. It could be concluded that 10 and 20 % replacement of reconstituted skim milk with coconut milk for the manufacture of Dahi was acceptable and reduced the production cost, but 10% replacement was better in compare to others, according to organoleptic, chemical and microbiological analysis.DOI: http://dx.doi.org/10.3329/bjas.v43i3.21653 Bang. J. Anim. Sci. 2014. 43 (3): 218-223

Green fluorescent protein-tagged sensor proteins, ArsR-GFP and CadC-GFP, have been produced as biosensors for simple and low-cost quantification of As(III) or Cd(II). In this study, the sensor protein-promoter DNA complexes were reconstructed on the surfaces of magnetic particles of different sizes. After the surface modification all the particles could be attracted by magnets, and released different amounts of GFP-tagged protein, according to the metal concentrations within 5 min, which caused significant increases in fluorescence. A detection limit of 1 µg/L for As(III) and Cd(II) in purified water was obtained only with the nanoparticles exhibiting enough magnetization after heat treatment for 1 min. Therefore, thermoresponsive magnetic nano-biosensors offer great advantages of rapidity and sensitivity for the measurement of the toxic metals in drinking water.

Recombinant Rhodopseudomonas palustris, harboring the carotenoid-metabolizing gene crtI (CrtIBS), and whose color changes from greenish yellow to red in response to inorganic As(III), was cultured in transparent microplate wells illuminated with a light emitting diode (LED) array. The cells were seen to grow better under near-infrared light, when compared with cells illuminated with blue or green LEDs. The absorbance ratio of 525 to 425 nm after cultivation for 24 h, which reflects red carotenoid accumulation, increased with an increase in As(III) concentrations. The detection limit of cultures illuminated with near-infrared LED was 5 microgram/l, which was equivalent to that of cultures in test tubes illuminated with an incandescent lamp. A near-infrared LED array, in combination with a microplate, enabled the simultaneous handling of multiple cultures, including CrtIBS and a control strain, for normalization by the illumination of those with equal photon flux densities. Thus, the introduction of a near-infrared LED array to the assay is advantageous for the monitoring of arsenic in natural water samples that may contain a number of unknown factors and, therefore, need normalization of the reporter event.

The research was carried out to compare the physical and chemical parameters of Swamp and Water buffalo milk collected from Senbari village in Trishal Upazila under Mymensingh district of Bangladesh. Results revealed that average color, flavor and taste score of Swamp and Water buffalo milk differed significantly (P0.05) with Water buffalo milk. Texture of all samples was normal. It was observed that average fat, total solids (TS), solids-not-fat (SNF) and protein content differed significantly (P0.05) were found among, acidity, water. From these results, it may be inferred that the quality of Swamp buffalo milk is superior to that of Water buffalo milk.

Transcriptional switches regulate gene expression in response to environmental changes surrounding cell. Many studies have focused on two fundamentally different models of transcriptional control by bacterial metalloregulatory protein. Distortion of the DNA fragment including cis-element, to which the trans-acting factor MerR binds, is accepted as the mechanism of gene expression regulation by Hg (II) while, in cases of the other trans-acting factors ArsR and CadC, events of association to and dissociation from cis-element are known to control transcription in response to As (III) and Cd (II), respectively. In this study, interactions between green-fluorescent-protein-tagged trans-acting factor and immobilized cis-element were analyzed on solid surface. Fluorescent measurements and surface plasmon resonance (SPR) responses revealed that although the equilibrium dissociation constant (KD) was much lower in MerR than in ArsR and CadC, the dissociation rate of MerR from DNA increased in response to Hg (II) at concentrations of 5-10(4) µg l(-1). These results firstly demonstrate an increase of KD between MerR and its recognition site in DNA by Hg (II), and possibility of rapid Hg (II) quantification with the low detection limit (5 µg l(-1)) and the high dynamic range (10(1)-10(4) µg l(-1)).

Jungle Crows (Corvus macrorhynchos) prefer human habitats because of their versatility in feeding accompanied with human food consumption. Therefore, it is important from a public health viewpoint to characterize their intestinal microbiota. However, no studies have been involved in molecular characterization of the microbiota based on huge and reliable number of data acquisition. In this study, 16S rRNA gene-based microbial community analysis coupled with the next-generation DNA sequencing techniques was applied to the taxonomic classification of intestinal microbiome for three jungle crows. Clustering of the reads into 130 operational taxonomic units showed that at least 70% of analyzed sequences for each crow were highly homologous toEimeriasp., which belongs to the protozoan phylumApicomplexa. The microbiotas of three crows also contained potentially pathogenic bacteria with significant percentages, such as the generaCampylobacterandBrachyspira. Thus, the profiling of a large number of 16S rRNA gene sequences in crow intestinal microbiomes revealed the high-frequency existence or vestige of potentially pathogenic microorganisms.

Environmental toxic metals cause serious global public health problems. On-site monitoring protects people from exposure to such harmful elements. In this study, the bacterial transcriptional switches were applied to monitoring of toxic metals. ArsR and CadC, trans factors of Escherichia coli and Staphylococcus aureus , were fused to GFP. The fusion proteins, ArsR–GFP and CadC–GFP, associated with cis elements, P ars – O ars and P cad – O cad , respectively and dissociated from those upon recognition of As(III) or Pb/Cd. Cell lysates containing ArsR–GFP were pre-incubated with As(III) standard solutions for 15 min and loaded into P ars – O ars -immobilized microplate wells. Cell lysates containing CadC–GFP were pre-incubated with Pb or Cd solutions and loaded into P cad – O cad -immobilized wells. The cell lysates were incubated for 15 min and removed from the wells. Fluorescence intensity in the wells dose-dependently decreased in response to As(III) up to 200 μg/l or Pb/Cd up to 100 μg/l. Detection limits were 10 μg/l for As(III) 10 μg/l for Cd, and 20 μg/l for Pb with a microplate fluororeader, whereas 5.0 μg/l for As(III), 1.0 μg/l for Cd, and 10 μg/l for Pb with a handheld fluorometer. This method was available to detect Pb/Cd or As(III) in water containing soil extracts. This is the first demonstration of a simple and rapid fluorometry to detect analytes based on in vitro interaction between a cis element and a trans factor.

This experiment assessed the quality of Rossogolla (Balish) manufactured in the laboratory and collected from Netrokona district. Four types of Rossogolla, (A) Laboratory made Rossogolla, (B) Rossogolla from Mukti Mistanno vander, (C) Rossogolla from Gwyneth Mistanno vander, (D) Rossogolla from Khan Mistanno vander were used in this experiment. Quality of Rossogolla were evaluated by physical, chemical and microbiological tests. From the physical examinations it appears that quality differed among different Rossogolla. Significant differences within flavour score, body and texture, colour and appearance and taste among the four different preparations of Rossogolla (P

Background From a human health viewpoint, contaminated milk and its products could be a source of long-term exposure to toxic metals. Simple, inexpensive, and on-site assays would enable constant monitoring of their contents. Bioassays that can measure toxic metals in milk or yoghurt might reduce the risk. For this purpose, the green fluorescent protein (GFP)-tagged trans factors, ArsR-GFP and CadC-GFP, together with their cis elements were used to develop such bioassays. Results ArsR-GFP or CadC-GFP, which binds either toxic metal or DNA fragment including cis element, was directly mixed with cow’s milk or yoghurt within a neutral pH range. The fluorescence of GFP, which is reflected by the association/dissociation ratio between cis element and trans factor, significantly changed with increasing externally added As (III) or Cd (II) whereas smaller responses to externally added Pb (II) and Zn (II) were found. Preparation and dilution of whey fraction at low pH were essential to intrinsic zinc quantification using CadC-GFP. Using the extraction procedure and bioassay, intrinsic Zn (II) concentrations ranging from 1.4 to 4.8 mg/l for milk brands and from 1.2 to 2.9 mg/kg for yoghurt brands were determined, which correlated to those determined using inductively coupled plasma atomic emission spectroscopy. Conclusions GFP-tagged bacterial trans factors and cis elements can work in the neutralized whole composition and diluted whey fraction of milk and yoghurt. The feature of regulatory elements is advantageous for establishment of simple and rapid assays of toxic metals in dairy products.