Changes in electrical conductivity and somatic cell count between milk fractions from quarters subclinically infected with particular mastitis pathogens

1998 ◽  
Vol 65 (2) ◽  
pp. 187-198 ◽  
Author(s):  
MURRAY W. WOOLFORD ◽  
JOHN H. WILLIAMSON ◽  
HAROLD V. HENDERSON

Cows with subclinical intramammary infections were identified by milk bacteriology. The mastitis pathogens included Staphylococcus aureus (n=9), Streptococcus uberis (n=10) and coagulase-negative staphylococci (n=10). Samples of first fore milk, main flow milk and strippings milk fractions were collected from each quarter and laboratory measurements were made of electrical conductivity, milk fat concentration and somatic cell count. Conductivity measurements were corrected for milk fat concentration and within-cow inter-quarter conductivity ratios calculated. Repeatability estimates of all measurements between days were calculated. In the case of infected quarters, all conductivity values decreased markedly (P<0·05) from first fore milk to main flow milk fractions. Conductivity differences between quarters of infected cows were substantially lower during the main milk flow phase. For quarters infected with Staph. aureus an increase in conductivity was observed (P<0·05) from main flow to strippings fractions. For uninfected quarters, conductivity declined as milk fat concentration increased with successive milk fractions. Variation, both within and between milk fractions, was greater for somatic cell count than for conductivity. Differences in conductivity between milk fractions from individual infected quarters were not accounted for by changes in fat concentration and may result from the mixing of milk from infected and uninfected regions of the gland. Localized infection may produce a decrease in conductivity between fore milk and mid-flow fractions while differential drainage from an infection site in the secretory tissue may additionally produce an increase in conductivity from mid-flow to strippings fractions. Such changes may thus provide information on the location and magnitude of an infection. The results clearly demonstrate the importance of the milk fraction when using conductivity as a diagnostic of intramammary infection, the highest diagnostic sensitivity being achieved by using first fore milk samples.

2003 ◽  
Vol 77 (2) ◽  
pp. 187-195 ◽  
Author(s):  
Y. de Haas ◽  
H.W. Barkema ◽  
Y.H. Schukken ◽  
R.F. Veerkamp

AbstractGenetic associations were estimated between pathogen-specific cases of clinical mastitis (CM), lactational average somatic cell score (LACSCS), and patterns of peaks in somatic cell count (SCC) which were based on deviations from the typical lactation curve for SCC. The dataset contained test-day records on SCC in 94 781 lactations of 25 416 cows of different parities. Out of these 94 781 lactations, 41 828 lactations had recordings on occurrence of pathogen-specific CM and on SCC, and 52 953 lactations had recordings on SCC only. A total of 5 324 lactations with cases of CM were recorded. Analysed pathogens were Staphylococcus aureus, coagulase negative staphylococci, Escherichia coli, Streptococcus dysgalactiae, Streptococcus uberis, and culture-negative samples. Pattern definitions were based on three or five consecutive test-day recordings of SCC. They differentiated between short or longer periods of increased SCC, and also between lactations with and without recovery. Occurrence of pathogen-specific CM and presence of patterns of peaks in SCC were both scored as binary traits. Variance components for sire, maternal grandsire, and permanent animal effects were estimated using AS-REML. The estimated heritability for overall CM was 0·04, and similar heritabilities for pathogen-specific CM were estimated. Heritabilities for the patterns of peaks in SCC ranged from 0·01 to 0·06. Heritabilities for LACSCS were 0·07 to 0·08. Genetic correlations with patterns of peaks in SCC differed for each pathogen. Generally, genetic correlations between pathogen-specific CM and patterns of peaks in SCC were stronger than the correlations with LACSCS. This suggests that genetic selection purely on diminishing presence of peaks in SCC would decrease the incidence of pathogen-specific CM more effectively than selecting purely on lower LACSCS.


Animals ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 1534
Author(s):  
Gisele Margatho ◽  
Hélder Quintas ◽  
Vicente Rodríguez-Estévez ◽  
João Simões

The external morphological traits of the mammary gland, and their relationships with somatic cell count (SCC) and the presence of intramammary infection (IMI), were studied in 30 Serrana goats, Transmontano ecotype. Globular-shaped udders were the most predominant, with slightly separated and symmetrical halves, presenting some degree of suspension. Funnel-shaped teats were the most prevalent shape with an opening of 120° to 160° degrees. Significant differences were observed between healthy group and the coagulase negative staphylococci (CNS)-infected group for udder cleft, teat perimeter and distance between teats parameters; and between healthy group and CNS or Staphylococcus aureus groups for degree of separation, teat shape and udder shape (p < 0.05). The udder shape, symmetry, degree of suspension and degree of separation parameters showed to be different depending on SCC (p < 0.05). The udder perimeter and udder depth traits showed differences between the lowest and the middle SCC group. We concluded that bifurcated pendular udders, with vertical loose teats and located close to each other, are more likely to have IMI, and have the highest SCC. The inclusion in breeding programs of certain mammary conformation traits would not only help to improve milk production, but would also decrease the susceptibility to IMI of the herd.


2010 ◽  
Vol 77 (3) ◽  
pp. 318-324 ◽  
Author(s):  
Otlis Sampimon ◽  
Bart HP van den Borne ◽  
Inge Santman-Berends ◽  
Herman W Barkema ◽  
Theo Lam

The effect was quantified of coagulase-negative staphylococci (CNS) intramammary infections on quarter- and cow-level somatic cell count (SCC) and on bulk milk somatic cell count (BMSCC) in different BMSCC cohorts in Dutch dairy herds. Two datasets were used for this purpose. In the first dataset, on 49 randomly selected dairy farms a total of 4220 quarter milk samples of 1072 cows were collected of all cows and heifers with a test-day SCC ⩾250 000 and ⩾150 000 cells/ml, respectively, and of 25% of cows and heifers below these thresholds. In the second dataset, on 39 selected dairy farms a total of 8329 quarter milk samples of 2115 cows were collected of all cows with a test-day SCC ⩾250 000 cells/ml following two consecutive SCC <250 000 cells/ml, and of heifers using the same SCC criteria but with a threshold of 150 000 cells/ml. These cows and heifers were defined as new high SCC. In both datasets, CNS was the most frequently isolated pathogen, 11% in the first dataset and 12% in the second dataset. In both datasets, quarters with CNS IMI had a lower SCC than quarters infected with major pathogens, and a higher SCC than culture-negative quarters. The same was found for SCC at cow level. Coagulase-negative staphylococci were more often found in quarters with SCC ⩾200 000 cells/ml in dairy farms with a BMSCC <150 000 cells/ml compared with dairy farms with a higher BMSCC. Prevalence of CNS in cows and heifers with a high SCC was higher in dairy farms with a BMSCC <150 000 cells/ml compared with dairy farms with a medium or high BMSCC: 30, 19 and 18%, respectively. This indicates that CNS IMI as a cause of subclinical mastitis is relatively more important in dairy farms with a low BMSCC and may become a point of attention in udder health management on that type of farm.


10.5219/1338 ◽  
2020 ◽  
Vol 14 ◽  
pp. 164-169
Author(s):  
Kristí­na Tvarožková ◽  
Vladimí­r Tančin ◽  
Michal Uhrinčať ◽  
Lukáš Hleba ◽  
Lucia Mačuhová

The aim of this study was to determine the occurrence of pathogens in selected group of ewes and the relationship between somatic cell count (SCC) and the presence of pathogens. The experiment was carried out on a dairy farm, where predominantly breed was a Tsigai. Sampling was carried out in monthly intervals as part of the milk recording test day from February to July 2019. A total of 303 ewes were included in the survey, during the milk recording test day. The ewes with SCC ≥1000 × 103 cells.mL-1 were selected for further sampling at half udder level. Based on SCC the ewes were divided into five groups: <200 ×103; ≥200 <400 × 103; ≥400 <600 × 103; ≥600 <1000 × 103; ≥1000 × 103 cells.mL-1. The first group of SCC contained 33.9% of milk samples, the second 14.1% of samples, the third 5.7% of samples, the fourth 6.2% and the fifth 40.1% of samples. The most common pathogens were coagulase negative staphylococci (CNS). The most frequent CNS was Staphylococcus (S.) simulans (24.4%). S. aureus was identified in 5.3% of bacteriological positive samples. Almost 70% of ewes with bacteriological positive samples were repeated identified the presence of pathogens during tested period. SCC ≥500 × 103 cells.mL-1  were detected in 92.5% bacteriological positive milk samples. The presence of pathogens increased SCC in milk (p <0.001) as compared to samples free of pathogens. In conclusion, the SCC ≥500 × 103 cells.mL-1 could be important for detection of subclinical mastitis at half udder level in dairy ewes.


Animals ◽  
2021 ◽  
Vol 11 (5) ◽  
pp. 1291
Author(s):  
Ryan S. Pralle ◽  
Joel D. Amdall ◽  
Robert H. Fourdraine ◽  
Garrett R. Oetzel ◽  
Heather M. White

Prediction of hyperketonemia (HYK), a postpartum metabolic disorder in dairy cows, through use of cow and milk data has allowed for high-throughput detection and monitoring during monthly milk sampling. The objective of this study was to determine associations between predicted HYK (pHYK) and production parameters in a dataset generated from routine milk analysis samples. Data from 240,714 lactations across 335 farms were analyzed with multiple linear regression models to determine HYK status. Data on HYK or disease treatment was not solicited. Consistent with past research, pHYK cows had greater previous lactation dry period length, somatic cell count, and dystocia. Cows identified as pHYK had lower milk yield and protein percent but greater milk fat, specifically greater mixed and preformed fatty acids (FA), and greater somatic cell count (SCC). Differential somatic cell count was greater in second and fourth parity pHYK cows. Culling (60d), days open, and number of artificial inseminations were greater in pHYK cows. Hyperketonemia prevalence decreased linearly in herds with greater rolling herd average milk yield. This research confirms previously identified risk factors and negative outcomes associated with pHYK and highlights novel associations with differential SCC, mixed FA, and preformed FA across farm sizes and production levels.


2015 ◽  
Vol 18 (4) ◽  
pp. 799-805 ◽  
Author(s):  
A. Bortolami ◽  
E. Fiore ◽  
M. Gianesella ◽  
M. Corrò ◽  
S. Catania ◽  
...  

Abstract Subclinical mastitis in dairy cows is a big economic loss for farmers. The monitoring of subclinical mastitis is usually performed through Somatic Cell Count (SCC) in farm but there is the need of new diagnostic systems able to quickly identify cows affected by subclinical infections of the udder. The aim of this study was to evaluate the potential application of thermographic imaging compared to SCC and bacteriological culture for infection detection in cow affected by subclinical mastitis and possibly to discriminate between different pathogens. In this study we evaluated the udder health status of 98 Holstein Friesian dairy cows with high SCC in 4 farms. From each cow a sample of milk was collected from all the functional quarters and submitted to bacteriological culture, SCC and Mycoplasma spp. culture. A thermographic image was taken from each functional udder quarter and nipple. Pearson’s correlations and Analysis of Variance were performed in order to evaluate the different diagnostic techniques. The most frequent pathogen isolated was Staphylococcus aureus followed by Coagulase Negative Staphylococci (CNS), Streptococcus uberis, Streptococcus agalactiae and others. The Somatic Cell Score (SCS) was able to discriminate (p<0.05) cows positive for a pathogen from cows negative at the bacteriological culture except for cows with infection caused by CNS. Infrared thermography was correlated to SCS (p<0.05) but was not able to discriminate between positive and negative cows. Thermographic imaging seems to be promising in evaluating the inflammation status of cows affected by subclinical mastitis but seems to have a poor diagnostic value.


Author(s):  
Tvarožková ◽  
Vašíček ◽  
Uhrinčať ◽  
Mačuhová ◽  
Hleba ◽  
...  

Mastitis is a major health problem of the udder in dairy sheep breeds. For diagnosis of subclinical mastitis, somatic cell count (SCC) is commonly used. The presence of pathogens in the udder causes the increase of leukocytes and thus SCC in milk. Therefore, the aim of this study was to evaluate the presence of pathogens in the milk of ewes and the possible relationship with SCC. The changes of leukocytes subpopulation in milk samples with high SCC were evaluated as well. The experiment was carried out on a dairy farm with the Lacaune breed. This study was conducted on 45 ewes (98 milk samples) without signs of clinical mastitis. Based on somatic cell count, samples were divided to five SCC groups: SCC1 &lt; 200 000 cells/ml (45 milk samples); 200 000 ≤ SCC2 &lt; 400 000 cells/ml (10 milk samples); 400 000 ≤ SCC3 &lt; 600 000 cells/ml (six milk samples); 600 000 ≤ SCC4 &lt; 1 000 000 cells/ml (six milk samples); SCC5 ≥ 1 000 000 cells/ml (31 milk samples). No pathogens were observed in the majority of milk samples (60.20%). Coagulase-negative staphylococci (CNS) were the most commonly isolated pathogens from the milk of ewes (86.11%). Staphylococcus epidermidis had the highest incidence from CNS (35.48%). In the SCC5 group, up to 79.31% of bacteriological samples were positive. The percentage of leukocytes significantly increased (P &lt; 0.001) in the samples with higher SCC (≥ 200 × 10<sup>3</sup> cells/ml) in comparison to the group SCC1. Also, the percentage of polymorphonuclear cells (PMNs) was significantly higher with increasing SCC (P &lt; 0.001). In conclusion, the presented results showed that the high SCC was caused by the presence of the pathogen in milk. Thus SCC &lt; 200 000 cells/ml and leukocyte subpopulation, especially PMNs, could be considered as important tools in udder health programs applied in dairy ewes.


2018 ◽  
Vol 39 (4) ◽  
pp. 1555
Author(s):  
Luiz Francisco Zafalon ◽  
Raul Costa Mascarenhas Santana ◽  
Sérgio Novita Esteves ◽  
Guilherme Aparecido Fim Júnior

The aims of this study were to determine the occurrence of subclinical mastitis in sheep of different breeds and the values for somatic cell count (SCC) in milk for the diagnosis of the disease at lactation and weaning, a fundamental prerequisite for identifying animals in need of control measures. Milk samples were obtained from 1,457 mammary halves of Santa Inês, Texel, Ile de France, and Dorper sheep at two different periods, during the second week of lactation and at weaning. After teats antisepsis, the samples were collected, and identification of the infectious etiology of mastitis and determination of SCC were performed. Microorganisms were identified in 117/762 (15.3%) mammary halves in the second week of lactation and in 86/694 (12.4%) at weaning. Coagulase-negative staphylococci (CoNS) were the etiological agents with the highest incidence alone and in association with other microorganisms, with percentages of 58.1% and 60.6%, respectively. The Santa Inês presented a higher incidence of subclinical mastitis when compared to the other breeds. The cut-off values of SCC for subclinical mastitis were determined at both sampling periods and varied according to stage of lactation, as well breed. These results illustrate the lack of a universal value that can be used for the diagnosis of mastitis and suggests the need for permanent follow-up in herds in order to control the disease.


2019 ◽  
Vol 31 (6) ◽  
pp. 498-503 ◽  
Author(s):  
Jale Metin Kiyici ◽  
Bilal Akyüz ◽  
Mahmut Kaliber ◽  
Korhan Arslan ◽  
Esma Gamze Aksel ◽  
...  

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