Do Milk Samples Stored for 12 Days after Collection Exhibit a Change in Composition Related to the Initial Bacterial Load?

2016 ◽  
Vol 79 (5) ◽  
pp. 816-820
Author(s):  
LARISSA NAZARETH de FREITAS ◽  
LAERTE DAGHER CASSOLI ◽  
JANIELEN da SILVA ◽  
JOSÉ CARLOS de FIGUEIREDO PANTOJA ◽  
PAULO FERNANDO MACHADO
Keyword(s):  
Room Temperature ◽  
Storage Time ◽  
Bacterial Load ◽  
Total Bacterial Count ◽  
Urea Nitrogen ◽  
Total Solids ◽  
Milk Samples ◽  
Milk Urea ◽  
The Impact ◽  
Milk Urea Nitrogen

ABSTRACT Total bacterial count (TBC) is a tool used to assess milk quality and is associated with not only the initial sample contamination but also the sample storage time and temperature. Several countries have reported milk samples with a high TBC, and the influence of TBC on milk preservation remains unclear. Thus, the aim of this study was to evaluate the impact of the initial bacterial contamination level on the macrocomponents and somatic cell count (SCC) of raw milk samples preserved with bronopol and maintained at two storage temperatures (7 and 25°C) for up to 12 days. Thus, we collected milk samples from 51 dairy farms, which were divided into two groups according to the initial bacterial load: low TBC (<100,000 CFU/ml) and high TBC (≥100,000 CFU/ml). We analyzed the sample composition for protein, fat, total solids, lactose, milk urea nitrogen, and the SCC. We did not observe an effect from TBC and storage time and temperature on the concentration of protein, fat, total solids, and lactose. SCC changes were not observed for samples maintained under refrigeration (7°C); however, samples maintained at room temperature (25°C) exhibited a decrease in the SCC beginning on day 6 of storage. For milk urea nitrogen, values increased when the samples were maintained at room temperature, beginning on the ninth storage day. Samples with the preservative bronopol added and maintained under refrigeration may be analyzed up to 12 days after collection, regardless of the milk microbial load.

scholarly journals Fourier Transform Infrared Spectroscopy (FTIR) for MUN analysis in normal and adulterated Milk

2012 ◽  
Vol 64 (5) ◽  
pp. 1360-1366 ◽  
Author(s):  
M.C.P.P. Oliveira ◽  
N.M.A. Silva ◽  
L.P.F. Bastos ◽  
L.M. Fonseca ◽  
M.M.O.P. Cerqueira ◽  
...  
Keyword(s):  
Fourier Transform ◽  
Fourier Transform Infrared ◽  
Raw Milk ◽  
Urea Nitrogen ◽  
Milk Samples ◽  
Automated Method ◽  
Significant Difference ◽  
Milk Urea ◽  
Repeatability And Reproducibility ◽  
Milk Urea Nitrogen

The objective of this study was to evaluate the CombiScope FTIR equipment based on Fourier Transform Infrared methodology (FTIR), to assess the content of milk urea nitrogen (MUN) in Brazil. Repeatability and reproducibility of CombiScopeTM FTIR (Delta Instruments), and comparison with an enzymatic automated method (Chemspec® 150; Bentley Instruments) were tested to measure raw milk urea nitrogen (MUN). Additionally, MUN levels stability after storage of raw milk samples at 4ºC, and 20ºC for up to 15 days, and capability and precision to detect extraneous urea added as an adulterant to the milk were evaluated by FTIR equipment. There was a high correlation coefficient for the analysis of MUN by FTIR equipment, when compared with the automated enzymatic method, with no significant difference between both. MUN concentration in raw milk remained stable at temperatures of 4ºC for up to 15 days of storage, but after 3 days of storage at 20ºC there was an increase in the MUN levels. The CombiScope FTIR equipment proved to be a reliable method for analysis of MUN content in raw milk. However, results for MUN were not linear with the amount of extraneous urea added to raw milk, having a significant difference for samples when 40mg/dL of urea was added to milk.

Milk urea-nitrogen negatively affected first-service breeding success in commercial dairy cows in Prince Edward Island, Canada

2007 ◽  
Vol 82 (1-2) ◽  
pp. 42-50 ◽  
Author(s):  
P. Arunvipas ◽  
J.A. VanLeeuwen ◽  
I.R. Dohoo ◽  
E.R. Leger ◽  
G.P. Keefe ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Breeding Success ◽  
Prince Edward Island ◽  
Urea Nitrogen ◽  
Milk Urea ◽  
Milk Urea Nitrogen

319 Predicting Urinary Nitrogen Excretion from Milk Urea Nitrogen of Fresh Forage or Total Mixed Ration Fed Dairy Cows: A Meta-analysis

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 171-171
Author(s):  
Matthew R Beck ◽  
Cameron Marshall ◽  
Konagh Garrett ◽  
Andrew P Foote ◽  
Ronaldo Vibart ◽  
...  
Keyword(s):  
Dairy Cows ◽  
Meta Analysis ◽  
Live Weight ◽  
Predictive Ability ◽  
Nitrogen Excretion ◽  
Good Precision ◽  
Urea Nitrogen ◽  
Total Mixed Ration ◽  
Milk Urea ◽  
Milk Urea Nitrogen

Abstract Urine nitrogen excretion (g/d; UN) represent a significant environmental impact for both confinement feeding and pastoral based dairy systems. It is difficult to measure UN directly due to animal handling and labor requirements, especially in forage based production systems. The currently available milk urea nitrogen (MUN) equations have been shown to overestimate UN excretion of grazing dairy cows compared with an equation using urinary creatinine and UN concentration, indicating that diet may alter the relationship between MUN and UN. This potential was explored using data retrieved (treatment means: n = 69 and 27 for fresh forage [FF] and total mixed ration [TMR] fed cattle, respectively) from the literature and new data obtained from dairy cows fed FF (n = 15) in metabolism crates was used to test the new equations. The TMR data from literature was further split into a training set (to develop the model; n = 53) and a test set (to validate the model; n = 16). There was an interaction for diet type (P < 0.01) where UN (g/d) = 0.023 × MUN (mg/dL) × live-weight (kg, LW) for TMR fed cattle, (similar to a pre-established equation); however, UN (g/d) = 0.015 × MUN × LW for FF fed cattle. For FF based equations, the New MUN equation and the creatinine equation showed good precision and accuracy (Lin’s CCC = 0.79 and 0.74, respectively) and adequate predictive ability (RMSEP = 29.8 and 35.9, respectively). The new MUN equation for TMR fed cattle showed excellent accuracy and precision (Lin’s CCC = 0.87) with good predictive ability (RMSEP = 24.3) for UN excretion (observed mean = 216.5 g/d). The new equations generated during this meta-analysis provide promising predictive ability of UN excretion, which can be used for management considerations, future research, and policy making.

scholarly journals Milk Urea Nitrogen and Infertility in Florida Holstein Cows

2000 ◽  
Vol 83 (3) ◽  
pp. 459-463 ◽  
Author(s):  
P. Melendez ◽  
A. Donovan ◽  
J. Hernandez
Keyword(s):  
Holstein Cows ◽  
Urea Nitrogen ◽  
Milk Urea ◽  
Milk Urea Nitrogen

scholarly journals ASSESSMENT OF SHELF LIFE AND BACTERIAL LOAD OF VIABLE EGGS OBTAINED AT THE POINT OF LAY FROM ROOM AND REFRIGERATOR STORAGE TEMPERATURES

2020 ◽  
Vol 3 (3) ◽  
pp. 62-65
Author(s):  
Obhioze Augustine Akpoka
Keyword(s):  
Shelf Life ◽  
Proteus Mirabilis ◽  
Room Temperature ◽  
Bacterial Load ◽  
Viable Count ◽  
Pseudomonas Sp ◽  
Storage Duration ◽  
Egg Storage ◽  
Salmonella Pullorum ◽  
The Impact

It is well established that storing hatching eggs over a longer period of time affects its quality. The current study evaluated the impact of egg storage duration in-relation to two different temperature conditions (room and refrigerator) to determine the bacterial load and shelf life of viable eggs. One hundred and twenty eggs were used for this study, 60 were boiled and 60 were raw. Thirty of the boiled eggs were stored at room temperature and the other 30 eggs were kept in the refrigerator. Similarly, 30 raw eggs were each stored at room and optimal refrigeration temperatures for eggs (< 7 oC) respectively, while the egg weight, viability and sensory tests were performed daily on the eggs. However, the eggs kept in the refrigerator were viable for longer and relatively maintained higher physical appearance and sensory quality compared to eggs kept at room temperature. In the investigation of bacterial load, the total viable count ranged from 6.0× 103 to 11.9 × 103 coliform forming unit per millilitre (cfu/ml) and 1.0 × 103 to 6.5 × 103 cfu/ml for the boiled eggs kept at room and refrigeration temperatures (BRT and BFT) respectively. More so, the bacterial counts in raw eggs obtained at room and refrigerator storage ranged from 4.8 × 103 to 6.5 × 103 cfu/ml. Subsequently, the characterization and identification of bacterial isolates indicated the presence of Salmonella pullorum, Proteus mirabilis and Pseudomonas sp. The Salmonella pullorum was isolated from all the egg samples (BRT, BFT, RRT and RFT). The Proteus mirabilis was isolated from boiled eggs kept in both room and refrigerator temperatures (BRT and BFT) while Pseudomonas sp. was obtained only from raw eggs stored in the refrigerator (RFT). In addition, the boiled eggs at room temperature started deterioration on Day 9, while its counterpart in the refrigerator began spoilage or decrease in quality from Day 16. The weight of the viable eggs in relation to the non-viable ones was statistically significant (P < 0.05). The refrigeration of eggs increases its longevity while proper hygiene and adequate boiling of eggs reduces the risk of acquiring infections through bacterial contamination.

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