Bulk Milk Research Articles

Does supply chain coordination impact supply chain performance? Evidence from dairy industry

The objective of this study is to identify extent of coordination among the supply stakeholders; measure supply chain performance and to study the impact of supply chain coordination on supply chain performance. The study is based on primary data collected from dairy supply chain stakeholders namely farmer-producers, bulk milk coolers (BMC), processing unit, wholesalers and retailers. The data was collected through combination of personal interviews, telephonic interviews and e-mail. The total sample size of this study is 420 spread across 28 firms with each firm representing a total of 15 respondents. Linear regression was performed to study the impact of supply chain coordination on supply chain performance. The results of this study reveal that supply chain coordination positively impacts all the supply chain performance metrics namely efficiency, responsiveness, flexibility and quality. Supply chain coordination has highest impact on supply chain responsiveness followed by supply chain quality, supply chain flexibility and supply chain efficiency. In case of impact of supply chain coordination on overall supply chain performance, there is an evidence of strong impact of supply chain coordination on supply chain performance.

Optimization of milk procurement routes of FPO owned dairy unit

Raw milk quality and quantity is the corner stone of excellent dairy products. Milk procurement guards this with an eagle eye and ensures that company’s production needs are met. Milk procurement is the starting point of FPO’s dairy supply chain. The FPO owned dairy unit has adopted a system of milk collection through village level milk pooling points (MPP’s). MPP is a common place in villages where the farmers pool their milk. The person who collects the milk from the farmers is called as “Pala Mitra” / “MPP operator”. The present study was carried out at the selected BMC centre of a FPO owned dairy unit in Chittoor district of Andhra Pradesh. The principal objective of the study was to optimize the milk procurement routes using travelling salesman model. The findings of the study show that in route-1 the optimized distance is 48.2 kilometers, time travelled to cover all the milk pooling points is 83.5 minutes and the total cost per trip is around 345 Rs. In route-2 optimized distance is 26.7 kilometers, time travelled to cover all the milk pooling points is 76 minutes and the total cost per trip is around 191 Rs. In route-3 optimized distance is 18.4 kilometers, time travelled to cover all the milk pooling points is 71 minutes and the total cost per trip is around 132 Rs.There was a significance reduction of total distance, time and cost in raw milk transportation for the identified bulk milk cooling unit with the optimization of routes was observed. The total distance for travelling to procure the milk to BMC unit has been reduced to 186.8 kilometers per day from 194.6 kilometers per day. The total time of travelling to procure milk to BMC unit was reduced from 501 minutes per day to 461 minutes per day. The total cost incurred for transportation of raw milk to BMC unit has been reduced from 1391.4 Rs. to 1335.6 Rs. With route optimization in all routes of identified bulk milk cooling unit a total reduction in cost of transportation of 55.77 Rs. per day could be achieved. As these transportation operations are routine and need to be done throughout the year an annual cost saving of 20,356 Rs. per annum for the identified BMC unit could be achieved.

Electrical energy prediction using a surface fitting model for an on-farm direct expansion bulk milk cooler (DXBMC) in South Africa

PurposeThis paper aims to show that a simplified surface fitting model can be efficient in determining the energy consumption during milk cooling by an on-farm direct expansion bulk milk cooler (DXBMC). The study reveals that milk volume and the temperature gradient between the room and the final milk temperature can effectively be used for predicting the energy consumption within 95% confidence bounds.Design/methodology/approachA data acquisition system comprised a Landis and Gyr E650 power meter, TMC6-HE temperature sensors, and HOBO UX120-006M 4-channel analog data logger was designed and built for monitoring of the DXBMC. The room temperature where the DXBMC is housed was measured using a TMC6-HE temperature sensor, connected to a Hobo UX120-006M four-channel analog data logger which was configured to log at one-minute intervals. The electrical energy consumed by the DXBMC was measured using a Landis and Gyr E650 meter while the volume of milk was extracted from on the farm records.FindingsThe results showed that the developed model can predict the electrical energy consumption of the DXBMC within an acceptable accuracy since 80% of the variation in the electrical energy consumption by the DXBMC was explained by the mathematical model. Also, milk volume and the temperature gradient between the room and final milk temperature in the BMC are primary and secondary contributors, respectively, to electrical energy consumption by the DXBMC. Based on the system that has been monitored the findings reveal that the DXBMC was operating within the expected efficiency level as evidenced by the optimized electrical energy consumption (EEC) closely mirroring the modelled EEC with a determination coefficient of 0.95.Research limitations/implicationsOnly one system was monitored due to unavailability of funding to deploy several data acquisition systems across the country. The milk blending temperatures, effects of the insulation of the DXBMC, were not taken into account in this study.Practical implicationsThe developed model is simple to use, cost effective and can be applied in real-time on the dairy farm which will enable the farmer to quickly identify an increase in the cooling energy per unit of milk cooled.Social implicationsThe developed easy to use model can be used by dairy farmers on similar on-farm DXBMC; hence, they can devise ways to manage their energy consumption on the farm during the cooling of milk and foster some energy efficiency initiatives.Originality/valueThe implementation of the developed model can be useful to dairy farmers in South Africa. Through energy optimization, the maintenance of the DXBMC can be determined and scheduled accordingly.

Разработка способа определения в сухом молоке соотношения относительных долей аллелей гена ϰ-казеина

Introduction. High-quality dairy products depend on the properties of raw materials. Milk is the basic raw material for all dairy products. Its quality is subject to requirements of biological safety, and its physicochemical and technological properties comply with strict indicators. ϰ-casein gene is a basic milk protein. Its allelic variants affect milk productivity, as well as its composition and technological properties, e.g. cheeseability and heat resistance. The research objective was to develop a new method for determining the ratio of the relative proportions of selection-significant kappa-casein gene alleles in bulk cow’s milk powder by means of molecular genetics and bioinformation system. The method can help to test raw materials for further processing rationality.
 Study objects and methods. The research included a genetic analysis of samples of bulk whole milk powder, bulk powdered skimmed milk, and bulk raw milk. The developed method involved DNA extraction, combined PCR-RFLP technique, electrophoretic results, and analysis detection of information data using new mathematical algorithms and software.
 Results and discussion. The ratio of the relative proportions of the kappa-casein gene alleles in milk powder was determined using primer sets JK5 and JK3, as well as restriction endonuclease HinfI for PCR-RFLP analysis. The experiment showed satisfactory reproducibility and interpretation of the obtained data. The program provided a ratio calculation of the kappa-casein gene alleles relative proportions in the studied milk powder samples, expressed as a percentage of the A allele proportion with additional indication of the absolute and relative errors. It also placed the information block of the generated numerical indicators into the percentage scale.
 Conclusion. The developed methodology was implemented by a set of laboratory procedures. The new specialized program “Calculation of the relative proportions ratio of ϰ-casein alleles in bulk milk” is on open access. It provides a correct and prompt data interpretation, generated during the analysis of dry milk raw materials of bulk origin.

Bioactive compound levels and sensory quality of partially skimmed organic yoghurts: Effects of the milk treatment, production season and starter culture*

The aim of the study was to assess the physicochemical properties, texture, colour and sensory quality of organic yoghurts with regard to the milk treatment (raw milk obtained directly from organic farms, partially skimmed and heat‐treated in the laboratory vs organic milk purchased in the shop that was pasteurised in a dairy), production season and starter culture. The yoghurts produced on the basis of bulk milk obtained from farms during the spring/summer season proved to be of greater nutritional value and had higher content of bioactive whey proteins, except for β‐lactoglobulin, and lipophilic vitamins than retail milk.

Detection of Brucella organisms from Egyptian raw milk using cultural and molecular techniques

Aim: This study aimed to detect Brucella organisms in Egyptian raw milk using cultural and molecular techniques.Methods: Two hundred bulk milk samples were collected from 2 cities at El-Gharbia and Kafer El-Sheikh Governorates during the summer and winter seasons. All samples were examined by the traditional cultural method and real-time polymerase chain reaction (qRT-PCR). All positive isolates were identified by biochemical tests and serotyping using monospecific antisera also examined by multiplex PCR primers for more identification.Results: Samples collected in summer seasons from the two cities showed no colonies characteristic to Brucella organisms while in winter season five samples showed positive characteristic features of Brucella organisms after culturing on Brucella specific media. Using qRT-PCR, 43 samples (13 in summer and 30 in winter) were positive for Brucella organisms. All positive RT-PCR samples and isolated strains were examined for the detection of the virulence genes Ure, bvfA and virB using conventional PCR. Ure, bvfA and virB were detected in 88%, 79% and 74% of milk samples and 100%, 80% 100% of isolates, respectively.Conclusion: These results suggested that the use of the specific PCR assay is a rapid, reliable, and accurate technique in comparison to traditional methods for the detection of Brucella species in milk samples.

Effects of the substitution of soybean meal by spirulina in a hay-based diet for dairy cows on milk composition and sensory perception

The demand for protein sources alternative to soybean meal for supplementing forages low in metabolizable protein is large. The suitability of spirulina (Arthrospira platensis), a fast growing and resource-efficient blue-green microalga, as a source of metabolizable protein for dairy cows is known, but its effects on milk antioxidants and sensory properties were never investigated. Twelve cows were allocated to 2 groups and fed hay-based diets complemented with sugar beet pulp and wheat flakes in individual feeding troughs. The N content per kilogram of DM was equivalent between the 2 diets. Diet of 1 group was supplemented with 5% spirulina; the second group was supplemented with 6% soybean meal (control). After an adaptation period of 15 d, data were collected, and feed, milk, blood, and rumen fluid were sampled. Feeds were analyzed for proximate contents, and blood plasma was analyzed for total antioxidant capacity and antioxidant contents (tocopherol, phenols). Milk samples were analyzed for fatty acid profile, coagulation properties, color, and contents of fat, protein, lactose, total phenols, lipophilic vitamins, and provitamins (e.g., β-carotene). Triangle tests were performed by a trained sensory panel on 6 homogenized and pasteurized bulk milk samples per treatment. The substitution of soybean meal by spirulina in the diet did not affect feed intake, milk yield, milk fat, protein, or lactose contents compared with the control group. However, the milk from the spirulina-fed cows had a higher content of β-carotene (0.207 vs. 0.135 μg/mL) and was more yellow (b* index: 14.9 vs. 13.8). Similar to the spirulina lipids but far less pronounced, the milk fat from the spirulina-fed cows had a higher proportion of γ-linolenic acid (0.057 vs. 0.038% of fatty acid methyl esters) compared with milk fat from soybean meal-fed cows. Also trans-11 C18:1 (vaccenic acid) and other C18:1 trans isomers were elevated, but otherwise the fatty acid profile resembled that of cows fed the control diet. No sensory difference was found between milk from the 2 experimental groups. Furthermore, we observed no effects of substituting soybean meal by spirulina on total antioxidant capacity, α-tocopherol and total phenols in blood and milk. Effects on rumen fluid characteristics were minor. In conclusion, spirulina seems to be a promising protein source for dairy cows with certain improvements in nutritionally favorable constituents in milk and without side-effects on animal performance in the short term.

Raw Milk Microbiota Modifications as Affected by Chlorine Usage for Cleaning Procedures: The Trentingrana PDO Case.

Milk microbiota represents a key point in raw milk cheese production and contributes to the development of typical flavor and texture for each type of cheese. The aim of the present study was to evaluate the influence of chlorine products usage for cleaning and sanitizing the milking equipment on (i) raw milk microbiota; (ii) the deriving whey-starter microbiota; and (iii) Trentingrana Protected Designation of Origin (PDO) cheese microbiota and volatilome. Milk samples from three farms affiliated to a Trentingrana PDO cheese factory were collected three times per week during a 6-weeks period in which a sodium hypochlorite detergent (period C) was used and during a subsequent 6-weeks period of non-chlorine detergent usage (period NC). Samples were subjected to microbiological [Standard Plate Count; coliforms; coagulase-positive staphylococci; and lactic acid bacteria (LAB)] and metagenomic analysis (amplification of V3-V4 regions of 16S rRNA gene performed on Illumina MiSeq platform). In addition, cheese volatilome was determined by SPME-GC-MS. In the transition from period C to period NC, higher SPC and LAB counts in milk were recorded. Milk metagenomic analysis showed a peculiar distinctive microbiota composition for the three farms during the whole experimental period. Moreover, differences were highlighted comparing C and NC periods in each farm. A difference in microbial population related to chlorine usage in bulk milk and vat samples was evidenced. Moreover, chlorine utilization at farm level was found to affect the whey-starter population: the usually predominant Lactobacillus helveticus was significantly reduced during NC period, whereas Lactobacillus delbrueckii had the exact opposite trend. Alpha- and beta-diversity revealed a separation between the two treatment periods with a higher presence of L. helveticus, L. delbrueckii, and Streptococcus thermophilus in cheese samples after NC detergent period. Cheese volatilome analysis showed a slight decrease in lipolysis during C period in the inner part of the cheese wheel. Although preliminary, these results suggest a profound influence on milk and cheese microbiota, as well as on raw milk cheese production and quality, due to the use of chlorine. However, further studies will be needed to better understand the complex relationship between chlorine and microbiota along all the cheese production steps.

The Effect of Selected Factors on the Content of Fat-Soluble Vitamins and Macro-Elements in Raw Milk from Holstein-Friesian and Simmental Cows and Acid Curd Cheese (Tvarog).

Simple SummaryDepending on the region, specific methods of cheese production are used. Acid coagulation is applied in the production of the traditional acid curd cheese highly valued in Poland, called ‘tvarog’. It is important to maintain the traditional nature of production that guarantees cheese with a high nutritional value and health-promoting properties. By conducting an analysis of tvarog, taking into account the quality of the raw milk and the type of starter cultures used, we found that the content of fat-soluble vitamins (A, D3, and E) mainly depended on the quality of the raw milk from which it was produced. A higher content of fat-soluble vitamins was found in milk obtained from Simmental cows kept in a traditional system in the spring/summer season and in the tvarog produced from it. Vitamin retention rates from raw milk to cheese were above 90%. In contrast, we noticed that the mineral composition of the cheese was not linked to the quality of the milk used. More Ca and Mg were lost with the whey, as indicated by the very low retention rates of these minerals from milk to tvarog (below 20%).The study was conducted to determine the content and retention of selected fat-soluble vitamins and minerals in curd cheese–tvarog made by a traditional method, taking into account the effect of the quality of the raw milk and the type of starter cultures used. The raw milk used to make the tvarog was obtained in various conditions, i.e., with and without the use of pasture forage (in a traditional and an intensive system), in two production seasons (spring/summer and autumn/winter), from two breeds raised in Poland (the Black-and-White variety of Polish Holstein-Friesian and Simmental). Two variants of starter cultures were used to make tvarog: Freeze-dried DVS starters (Flora Danica) and pure cultures of mesophilic lactic acid bacteria. The acidity and content of protein, fat, selected fat-soluble vitamins (A, D3, and E), and selected macro-elements (Ca and Mg) were determined in samples of bulk milk and cheese. Retention rates of individual nutrients from the milk to the cheese were calculated. A higher content of fat-soluble vitamins was found in milk obtained from Simmental cows kept in a traditional system in the spring/summer season, as well as in the tvarog produced from it. Vitamin retention rates from the raw material to the tvarog were above 90%. The mineral composition of the cheese was not associated with the quality of the milk used. Very low retention rates from milk to cheese were obtained for Ca and Mg (below 20%). Higher retention rates were obtained in the spring/summer season when culture variant 1 was used. However, the starter culture was not found to significantly influence the concentration or retention of vitamins in the experimental cheese.

Temporal trends in bulk tank milk antibody ELISA and PCR test results for bovine viral diarrhoea in New Zealand pastoral dairy herds

ABSTRACT Aims: To describe temporal trends in bulk milk antibody ELISA and PCR testing for bovine viral diarrhoea (BVD) in New Zealand pastoral dairy herds and to assess the use of historical accession data to predict herd-level BVD incursions. Methods: Data on all diagnostic testing of bulk milk for BVD performed by the Livestock Improvement Corporation (Hamilton, NZ) over eight lactation seasons from 1 June 2010 to 31 May 2018 were analysed. This included anonymised herd identification, geographic location, herd size, sample collection date, sample to positive (S/P) ratio for antibody ELISA results, and cycle threshold values for PCR detecting viral RNA. Multivariable logistic regression was used to explore the relationship between historical accession data and the risk of herds having at least one positive bulk milk PCR test result in the 2017 season. Results: There were 156,034 bulk milk BVD diagnostic testing accessions for 10,495 uniquely identified dairy herds over the 8-season period. The prevalence of tested herds with at least one positive bulk milk PCR test result decreased from 14.6% (407/2,786) in the 2010 season to 5.6% (355/6,309) in the 2017 season with similarly marked declines in S/P ratios. In the 2017 season, 2,961/6,309 (46.9%) herds had S/P ratios greater than the 0.75 cut-off value indicating recent or active BVD virus transmission within the herd while 1,422/6,309 (22.5%) herds were classified as having negative or low S/P ratios. Herds that cleared BVD from the milking herd experienced a mean decline in S/P ratio of 0.11 units per year (min 0.05; max 0.18). In the multivariable analysis, the overall incidence risk of herds experiencing a BVD incursion in the 2017 season was 3.8% (146/3,848) and there were three significant predictors in the final model: herd size, PCR status in the 2014 season, and change in S/P ratio between the 2014 and 2015 seasons. The area under the receiver operating curve for the final model was 0.695 indicating poor discrimination. Conclusions and clinical relevance: The prevalence of dairy herds in New Zealand with positive bulk milk PCR test results and high S/P ratios has decreased over time, suggesting fewer herds are actively infected with BVD and that herd immunity may also be declining. Although monitoring trends in bulk milk test results provides useful information on changes in individual herd status, it is difficult to accurately predict when new incursions will occur and farmers should continue to maintain good biosecurity.

Modelling spread and surveillance of Mycobacterium avium subsp. paratuberculosis in the Swedish cattle trade network

To monitor a state of disease freedom and to ensure a timely detection of new introductions of disease, surveillance programmes need be evaluated prior to implementation. We present a strategy to evaluate surveillance of Mycobacterium avium subsp. paratuberculosis (MAP) using simulated testing of bulk milk in an infectious disease spread model. MAP is a globally distributed, chronic infectious disease with substantial animal health impact. Designing surveillance for this disease poses specific challenges because methods for surveillance evaluation have focused on estimating surveillance system sensitivity and probability of freedom from disease and do not account for spread of disease or complex and changing population structure over long periods. The aims of the study were to 1. define a model that describes the spread of MAP within and between Swedish herds; 2. define a method for simulation of imperfect diagnostic testing in this framework; 3. to compare surveillance strategies to support surveillance design choices. The results illustrate how this approach can be used to identify differences between the probability of detecting disease in the population based on choices of the number of herds sampled and the use of risk-based or random selection of these herds. The approach was also used to assess surveillance to detect introduction of disease and to detect a very low prevalence endemic state. The use of bulk milk sampling was determined to be an effective method to detect MAP in the population with as few as 500 herds tested per year if the herd-level prevalence was 0.2 %. However, detection of point introductions in the population was unlikely in the 13-year simulation period even if as many as 2000 herds were tested per year. Interestingly, the use of a risk-based selection strategy was found to be a disadvantage to detect MAP given the modelled disease dynamics.

Bacterial Biofilm Formation in Milking Equipments in Lilongwe, Malawi

Background: Some microorganisms can adhere to food handling surfaces forming biofilms that pose a safety challenge. This study was done to evaluate bacterial biofilm formation in milking equipments in Lilongwe, Malawi. Methods: Pooled milk (n=54) and water (n=60) samples were collected from households and milk bulking groups in Lilongwe, Malawi. Swabbing (n=46) and rinsing (n=16) were done on milk handling containers after cleaning. Biofilm determination on the containers was done by detecting biofilm indicator bacteria, including Bacillus spp., Salmonella spp., and Pseudomonas spp. The strength of biofilm was determined by the tube method. Data were analyzed by SAS software version 9.1.3. Results: Prevalence rates of Gram-negative rods were significantly (p<0.05) higher than the Gram-positive rods and the Gram-positive cocci. Of the 176 cases, contamination rates were 36 (20.4%), 32 (18.2%), and 18 (10.2%) for Salmonella spp., Bacillus spp., and Pseudomonas spp., respectively. The biofilm indicator organisms were significantly (p<0.05) more prevalent in dairy farmer households compared with the milk bulking centers. Fourteen out of 86 (16.3%) microbial isolates formed strong/high biofilms, whereas 18 out of 86 (20.93%) of isolates did not form any biofilm. The rate of isolates forming strong/high biofilms in households (17.6%) was significantly (p<0.05) higher than that of milk bulking centers (11.1%). Conclusion: Biofilm formation on milk handling container surfaces in Lilongwe, Malawi could serve as a source of microbial pathogens and spoilage organisms.

Physicochemical and microbiological characteristics of goat milk from animals grown in a mountainous area in Bulgaria

Abstract. The aim of the study was to determine the goat milk quality from animals grown in a mountainous area in Bulgaria based on physicochemical and microbiological parameters. The study was carried out in a farm that breeds local goats and goats of the Bulgarian White Dairy Goat (BWD). Individual milk samples were taken on a monthly basis from morning milking. A total of 100 individual and 10 bulk milk samples were examined for fat, solids non fat, protein and density. A total of 62 samples were collected at a time to determine the microbiological characteristics of milk. For the period May-September 2017, the percentage of fat in the milk of local goats averaged 3.61% and of goats from BWD goat – 3.54%. The solids non fat were 8.27% and 8.19%, total protein – 3.13% and 3.10%, and the dry matter – 11.89% and 11.74%, respectively. For the period May-August 2017 the individual constituents of milk changed to varying degrees with the most variable being milk fat (decrease of 0.97% in local goats’ milk and 1.09% in milk from BWD goat) followed by solids non fat (0.56% and 0.7%, respectively). The slightest change was in protein – 0.21% and 0.26%, respectively. Coagulase-negative staphylococci were the predominant bacterial species in the goats’ milk samples.

Effective Factors on the Amount and Type of Consumption Milk in Ardabil City of Iran: A Descriptive Study

Background: Among various food products, milk is among the most basic nutrient foods. Studies demonstrated that consumption of milk and its products are low in Iranian families. This study was conducted to investigate the type and amount of milk consumption in Ardabil city in 2015-2016. Methods: This descriptive study was conducted among 300 people (199 female and 101 male), who referred to health centers of Ardabil. The participants were selected from both genders of healthy people with no diseases aged ≥18 years. Some questioners were applied to measure milk consumption. Results: Of 300 studied people, 51.67% consumed pasteurized milk, 40.67% consumed fresh (Bulk) milk, and 4.67% used both of them, while 3% did not use any type of milk. Among the milk company brands, Mihan was the first choice and had the highest consumption rate; 87% of people paid attention to the quality of milk in choosing one brand. Most people used Teflon cookware for boiling milk and many of them used a glass bottle for storing it. Conclusion: Posturized milk has the highest consumption rate. A few people did not consume milk in Ardabil and the quality of milk was the most important factor for its consumption. A significant association was found between the type of consumed milk and the individuals' educational level, age, and the household head's educational status. More extensive studies at the national level should be conducted to investigate the causes and effective factors in solving the current problems with regard to milk consumption.

Prevalence and antibiotic susceptibility profile of <I>Staphylococcus aureus</I> from milk and milk products in Nasarawa State, Nigeria

This study determined the prevalence and antibiotic susceptibility profile of Staphylococcus aureus isolated from milk and milk products in Nasarawa State, Nigeria. A total of 180 samples comprising of fresh raw milk, bulk milk, Nono, and Kindirmo were collected over a period of 6 months. Standard microbiological procedures were employed in the isolation, identification, characterization and determination of the antibiogram of S. aureus from the milk samples. Characterization was achieved by morphological, biochemical characteristics using conventional methods and Microgen® STAPH-ID kits. The isolates were tested for susceptibility or resistance to a panel of 11 commonly used antibiotics using the agar disc diffusion technique. Out of the 180 milk samples examined, nine (9) S. aureus were isolated giving a prevalence of 5.0%. The occurrence of S. aureus was higher in Nono (12.1%) and Kindirmo (10.6%) than in fresh raw milk (5.9%). The kind of water (well water) used for cleaning utensils at the Nono and Kindirmo selling points was found to be a risk factor associated with the occurrence of S. aureus in the products. All of the isolates were resistant to cefoxitin (100%), ampicillin (100%), and amoxicillin/clavulanic acid (100%). The isolates displayed various rates of resistance to erythromycin (22.2%), sulphamethoxazole/trimethoprim (22.2%), and tetracycline (44.4%). Five (5) antibiotic resistance patterns were recorded among the isolates an indication of different levels of use and misuse of antibiotics in the areas studied. The detection of Staphylococcus aureus in fresh and fermented milk in the areas studied suggests that consumption of dairy products especially those produced using traditional methods, constitute a hazard to consumers. It is recommended that since compliance with basic hygiene requirements is not guaranteed, hazard analysis and critical control points (HACCP) concepts should be seen as a part of an effective total hygiene concept at the selling points.
 Keywords: Antibiotic susceptibility profile, Milk, Nasarawa State, Nigeria, Prevalence, Staphylococcus aureus

Repeatability of a Commercially Available ELISA Test for Determining the Herd-Level Salmonella enterica subsp. enterica Serovar Dublin Status in Dairy Herds Using Bulk Milk.

An Enzyme-Linked Immunosorbent Assay (ELISA) is currently available for detection of antibodies against Salmonella Dublin in bovine milk. However, when used in a surveillance program, samples may undergo various storage conditions. The objective of this study was to estimate the repeatability of an ELISA test when used on fresh and frozen samples. Each of 845 bulk milk collected samples was subdivided into 3 aliquots and analyzed using PrioCHECK™ Salmonella Ab Bovine Dublin. ELISA percent positivity results (PP%) were compared between aliquots submitted to the initial analysis and a second analysis conducted 24 h later. The third aliquots were either preserved for 13–14 days (n = 413) or 25–28 days (n = 432) at −20°C prior to analysis and results were compared to the initial analysis. There was excellent concordance between the two initial values and with values obtained after 13–14 and 25–28 days-freezing. The corresponding concordance correlation coefficients were 0.96, 0.97, and 0.94, respectively. Bland-Altman plots showed differences of PP% of 0.1 percentage points on average between the initial and second fresh samples. Freezing for 13–14 and 25–28 days led to overestimation of the initial values by 0.1, and 0.4 percentage points, respectively. Regarding the classification of samples, greater disagreement was observed between 25 and 28 days-frozen and initial samples when using the cut-off 15% (kappa = 0.76) compared to 35% (kappa = 0.90). Our study showed that PrioCHECK™ has good repeatability and that frozen bulk milk samples could generate reliable results. However, the larger variability at lower PP% should be considered when setting up a threshold.

Quality Profile of Single-Breed Alpine Grey and Pinzgauer Bulk Milk

The aim of the present study was to investigate sources of variation in bulk milk composition, somatic cell score, coagulation properties, and mineral content of Alpine Grey and Pinzgauer single-breed herds in the Italian alpine area. A total of 56,914 bulk milk samples from 461 farms located in the Bolzano province (Northeast Italy) were available for statistical analysis. Least squares means revealed that Pinzgauer herds produced milk with greater fat content and shorter rennet coagulation time than Alpine Grey herds, but the latter had greater milk protein content and lower somatic cell scores than Pinzgauer herds. The greatest content of Ca, protein, and casein and the most favorable coagulation properties were observed in milk sampled in autumn in both breeds. Results should serve to differentiate the milk of Alpine Grey cattle and Pinzgauer cattle from milk of other cattle breeds and thus provide necessary arguments for developing new production concepts that might expand future opportunities for further valorizing these local, dual-purpose breeds and therefore contribute long-term to their preservation.

Optimal surveillance against foot-and-mouth disease: A sample average approximation approach.

Decisions surrounding the presence of infectious diseases are typically made in the face of considerable uncertainty. However, the development of models to guide these decisions has been substantially constrained by computational difficulty. This paper focuses on the case of finding the optimal level of surveillance against a highly infectious animal disease where time, space and randomness are fully considered. We apply the Sample Average Approximation approach to solve our problem, and to control model dimension, we propose the use of an infection tree model, in combination with sensible ‘tree-pruning’ and parallel processing techniques. Our proposed model and techniques are generally applicable to a number of disease types, but we demonstrate the approach by solving for optimal surveillance levels against foot-and-mouth disease using bulk milk testing as an active surveillance protocol, during an epidemic, among 42,279 farms, fully characterised by their location, livestock type and size, in the state of Victoria, Australia.

Influence of subclinical mastitis and intramammary infection by coagulase-negative staphylococci on the cow milk peptidome

Coagulase-negative staphylococci (CNS) are the most prevalent microorganisms isolated from cow milk and are associated with subclinical mastitis and persistent increases in the bulk milk somatic cell count (BMSCC) of low BMSCC herds. By combining peptide enrichment, LC-ESI-MS/MS, and statistical analysis, we investigated the influence of subclinical mastitis and CNS infection on the milk peptidome. Quarter milk samples from clinically healthy Holstein cows were subjected to bacteriological culture (BC) and somatic cell counting (SCC) for two consecutive samplings and 28 (including 11 negatives and 17 positives) were selected for peptidomic analysis.The study identified 1363 different endogenous peptides and highlighted a significant increase of peptides in CNS-positive milk, mainly represented by casein fragments. Milk peptidome changes increased with the SCC, as also demonstrated by protein electrophoresis and densitometry. Peptides significantly different in CNS or CONTROL samples were identified and characterized. Our results indicate that subclinical mastitis by CNS can induce significant changes in the milk peptidome, opening the way to future studies for the identification of a biomarker panel as well as for the understanding of their consequences for the technological and sensorial characteristics of cow milk and dairy products. SignificanceThis is the first investigation on the impact of subclinical CNS mastitis on the bovine milk peptidome. The peptide enrichment strategy combined with a highly sensitive MS/MS analysis enabled the compilation of a very large peptide dataset for healthy and mastitic milk. The comparison of CNS and Control samples, also considering SCC classes, highlighted several peptides with potential for understanding milk protein and peptide dynamics in subclinical mastitis, with possible implications for its detection.

Comparison of Fatty Acid Proportions Determined by Mid-Infrared Spectroscopy and Gas Chromatography in Bulk and Individual Milk Samples.

Simple SummaryInformation about fatty acid proportions in milk fat is important for many purposes, such as animal breeding, animal health control, as well as human nutrition. The routine methods for determining fatty acid proportions (e.g., mid-infrared spectroscopy) are rapid and relatively cheap, but there is a need to compare them with the reference analytical method (gas chromatography) to ensure their validity and suitability for various milk samples. The aim of this study is to compare the proportions of single fatty acids and their sums determined by utilizing both of these analytical methods and the resulting correlation coefficients. Our results show that the mid-infrared spectroscopy method is more appropriate (both for bulk and individual milk samples) for fatty acids present in high proportions of the total fat and for the sum of fatty acids (such as saturated and unsaturated) than for fatty acids with low proportions.Rapid analytical methods can contribute to the expansion of milk fatty acid determination for various important practical purposes. The reliability of data resulting from these routine methods plays a crucial role. Bulk and individual milk samples (60 and 345, respectively) were obtained from Czech Fleckvieh and Holstein dairy cows in the Czech Republic. The correlation between milk fatty acid (FA) proportions determined by the routine method (infrared spectroscopy in the mid-region in connection with Fourier transformation; FT-MIR) and the reference method (gas chromatography; GC) was evaluated. To validate the calibration of the FT-MIR method, a linear regression model was used. For bulk milk samples, the correlation coefficients between these methods were higher for the saturated (SFAs) and unsaturated FAs (UFAs) (r = 0.7169 and 0.9232; p < 0.001) than for the trans isomers of UFAs (TFAs) and polyunsaturated FAs (PUFAs) (r = 0.5706 and 0.6278; p < 0.001). Similar results were found for individual milk samples: r = 0.8592 and 0.8666 (p < 0.001) for SFAs and UFAs, 0.1690 (p < 0.01) for TFAs, and 0.3314 (p < 0.001) for PUFAs. The correlation coefficients for TFAs and PUFAs were statistically significant but too low for practical analytical application. The results indicate that the FT-MIR method can be used for routine determination mainly for SFAs and UFAs.