Bulk Milk Tank Samples Are Suitable to Assess Circulation of Tick-Borne Encephalitis Virus in High Endemic Areas

A reliable surveillance strategy of tick-borne encephalitis virus (TBEV) is necessary to ensure adequate disease control measures. However, current approaches assessing geographical TBEV circulation are ineffective or have significant limitations. In this study we investigated a total of 1363 goat and 312 sheep bulk tank milk samples for the presence of TBEV. Samples were collected from systematically selected farms in Lithuania every 4–5 days from April to November in 2018 and 2019. To validate results, we additionally tested 2685 questing ticks collected in the vicinity of milk collection sites. We found 4.25% (95% CI 3.25–5.47) and 4.48% (95% CI 2.47–7.41) goat and sheep milk samples to be positive for TBEV, respectively. Furthermore, geographical distribution of TBEV in milk samples coincided with the known TBE endemic zone and was correlated with incidence of TBE in humans in 2019. When sampling time coincides, TBEV detection in milk samples is as good a method as via flagged ticks, however bulk milk samples can be easier to obtain more frequently and regularly than tick samples. The minimal infectious rate (MIR) in ticks was 0.34% (CI 95% 0.15–0.64). Therefore, our results confirm that testing milk serves as a valuable tool to investigate the spatial distribution of TBEV at higher resolution and lower cost.

Management of high cows-share-contribution of SCC to the bulk milk tank by acoustic pulse technology (APT)

A cow with mastitis has a high somatic cell count (SCC) in its milk. Cow-share-contribution of somatic cells to the bulk milk tank (BMTSCC) refers to the relative addition made by each cow’s milk to the bulk tank’s SCC. Since bulk milk is graded and priced according to the BMTSCC, high-yielding cows with mastitis are the main contributors to penalizations in milk price. The benefits of acoustic pulse technology (APT) application to tissues are well documented, including its anti-inflammatory effect and restoration of tissue function by triggering natural healing processes. An APT-based device was developed specifically for treating mastitis in dairy cows. It enables rapid and deep penetration of the acoustic pulses over a large area of the udder in a single session. A study was performed on six farms with a total of 3,900 cows. One unit of cow-share-contribution equaled the addition of 1,000 cells to each mL of the bulk milk volume above the mean BMTSCC. A total of 206 cows were selected: 103 were treated with APT and 103 served as controls. All of the cows contributed over 1.5 units to the BMTSCC at the time of treatment. Seventy-five days after APT treatment, 2 of the 103 treated cows (1.9%) were culled, compared to 19 (18.5%) of the 103 control cows, as well as infected quarter dry-off in 5 others (4.85%). Overall success was defined as a decrease of >75% in cow-share-contribution from treatment time in two of the three monthly milk recordings following treatment. Results indicated 57.3% success for the APT-treated cows vs. 14.6% for the untreated control groups. Highest share-contribution provide an additional tool for the farmer’s decision of how to control BMTSCC. Because the cow-share-contribution value is relative to herd size and BMTSCC, this study included a similar number of cows, with similar SCC and milk yield from each of the six herds.

Staphylococcus aureus and Mesophilic Aerobic Bacteria Quantification in Hygienization Process of Milking Equipment

Background:Milk’s composition is an excellent substrate for microorganism’s multiplication. Presence of Staphylococcus aureus and aerobic mesophilic bacteria are one of the most common problems in dairy farms. On dairy industry’s and milk farms Clean in Place (CIP) system higyenization are commonly used, then the cleaning occurs as a closed process, for better results sanitizans are applied, in order to obtain a safety food. This project aim to evaluate Staphylococcus aureus and aerobic mesophilic bacteria reduction after two milking higyenization process. Materials, Methods & Results:This research was done on a Rio Grande do Sul North Milk farm, with mechanized milking and Clean in Place system for cleaning. For liners and CIP tubes higyenization commercial products as Sodium Hipoclorite 3% and phosphoric acid 11.3% are used for detergency, and peracetic acid 5% for sanitization. Milk bunk tank are higyenized with sodium hypoclorite 3.8% alcalin detergent. After higyenization steps liners, CIP’s water process, bulk milk tank and milk set were collected. At process 1, liners and CIP water were collected after milking, detergency and sanitization that occurred immediately at the detergency’s finish, while process 2 the sanitization was realized 8 h after detergency, before following milking. Cooling milk bulk tank was collected before and after detergency, and milk set after milkings Convencional microbiology were used to count and results in log10 UFC.cm-2. In CIP water’s after process 1 was 3.81 log10 reduction to aerobic mesophilic bacteria (P > 0.05) and reducing 4.51 log10 (P = 0.03). Meanwhile there was no significant reduction for mesophilic aerobic bacteria and S. aureus on the others samples (liners, bulk milk tank and milk set).Discussion: This results show the maintenance of milking machine contamination, and that even bacterial load reduced among hygienization steps this was not significant, suggesting that deteriorate and pathogenic microorganisms can remain on milk produced. Highlights are teat taps of milking machine as the major cause of contamination among cows. The results are worrying because Staphylococcus aureus contamination, once this bacteria causes alimentar diseases, even after higyenization process, which can damage public health that can reflect milk chain economically. Since amount of this microorganism found in milk is already sufficient to synthesize enterotoxins. In addition, resistance to disinfectants is another concern, as it may result in resistance to antimicrobial agents. So reduction of bacteria level among cleaning steps there was no significance, once the products and equipments on dairy and farms act as a constant elimination point of deteriorate and pathogenic microorganisms for the final product, milk. With this studies aim to aprimorate hygienization process on milk chain, in order to obtain a hygienic sanitary good product.

Survey of pyrethroid, macrocyclic lactone and antibacterial residues in bulk milk tank from Minas Gerais State, Brazil

ABSTRACT: A survey of veterinary drug residues in bulk milk tank from Minas Gerais State, Brazil, was carried out through a broad scope analysis. Here, 132 raw milk samples were collected at 45 dairy farms in Minas Gerais from August 2009 to February 2010, and analyzed for 42 analytes, comprising pyrethroids, macrocyclic lactones and antibacterials, using liquid chromatography coupled with mass spectrometry in tandem mode and gas chromatography with electron capture detection. Within all milk samples, at least one veterinary drug residue was identified in 40 milk samples (30.30%) by confirmatory tests, whereas 16 samples (12.12%) showed the presence of at least two residues. With regard to the Brazilian maximum residue levels, 11 milk samples (8.33%) were non-compliant according to Brazilian Legislation. The veterinary drugs detected in the non-compliant milk samples include penicillin V (one sample), abamectin (one sample) and cypermethrin (nine samples). Furthermore, the antibacterial screening methods failed to identify most of the positive samples that were detected by confirmatory tests, leading to a large discrepancy between the screening and confirmatory antimicrobial tests. Thus, the present study indicated that the veterinary drugs residues still represents a great concern for the milk production chain.

Climate conditions associated with the occurrence of pyrethroid residues in bulk milk tank

ABSTRACT The present study attempted to identify climate conditions that are associated with the occurrence of pyrethroid residues using a multivariate principal component analysis (PCA). A total of 132 raw milk samples were collected from dairy farms in Minas Gerais State - Brazil and analyzed for seven analytes using gas chromatography with electron capture detection. Of the 132 milk samples, pyrethroid residues were identified in 14 (10.6%) milk samples, of which 12 (9.1%) and two (1.5%) milk samples had the identification of cypermethrin and deltamethrin, respectively. From those samples, nine (6.8%) milk samples were regarded as non-compliant for cypermethrin with this analyte concentration above the maximum residue limits set by Brazilian legislation. A PCA assessing pyrethroid residues in bulk tank milk demonstrated that the average temperature and the Temperature-Humidity Index were associated with pyrethroids residues in bulk milk tank, although the relative humidity was inversely correlated. Thus, the data analysis indicated that the pyrethrid residues associated with some climate conditions can predict the moments with higher risk of occurrence of pyrethroid residues in bulk tank milk.

Parasites in dairy cattle farms in southern Brazil

Objective. The aim of this study was to investigate the relation among type and size of the farms related to the management of production and especially the presence and control of parasites. Materials and methods. To accomplish the above, 65 farms were used: 56 of semi-extensive system (cows in pastures), classified as low density farms (n=15, up to 15/cows), medium density farms (n=20; between 16-30/cows) and large density farms (n=21; over 31/cows). It was also included nine farms freestall system (n=9; confinement, over 70 cows) as part of the study population. Results. In the farms visited for the study can be noticed that the farms that had the higher level of technological improvement in managements practice were properties in high level (3) and freestall (4). In most of the farms there were observed the presence of ticks and flies, regardless of density of farms. Feces samples collected from 650 cows (n=10/farm), and analyzed using McMaster showed that 191 cows were positive for parasites. The presence of antibodies in bulk milk tank occurred in 36 (55.38%; CI95% 42-67) to Neospora caninum of the studied farms. Conclusions. We also conclude that N. caninum is present in cattle herds in Western Santa Catarina, and may be linked to reproductive problems in cows.

Comparison of Virus Isolation and Reverse Transcription Polymerase Chain Reaction Assay for Detection of Bovine Viral Diarrhea Virus in Bulk Milk Tank Samples

The use of a reverse transcriptase polymerase chain reaction (RT-PCR) assay to screen bulk milk tank samples for bovine viral diarrhea virus (BVDV) has proven to be a sensitive and economical means to evaluate the lactating animals in a herd. The assay is capable of detecting the presence of a single persistently infected animal within a group of several hundred cows. Over a 3–year period, 144 samples from 97 farms were tested for BVDV using an RT-PCR assay in conjunction with a classical virus isolation (VI) procedure to measure the relative effectiveness of the techniques. Virus could be detected with both methods when the milk from a single persistently infected animal was diluted 1:600 with the milk from a herd of BVDV-negative animals. Based on individual farms, there was an overall prevalence of 12.4% BVDV infection, and the correlation between the 2 assays was 95.9%. In terms of sensitivity, specificity, and turnaround time, RT-PCR was superior to VI. However, of the 17 samples that were VI positive, 4 were RT-PCR negative. RT-PCR may not detect all naturally occurring BVDV isolates because they may contain minor sequence variations in the primer regions. VI and RT-PCR are both suitable for detection of BVDV in bulk milk samples when used independently, but to increase the probability of successful detection and to provide cross-checks against assay contamination, it is desirable to utilize both methods in parallel.