The contribution of mammary infections by coagulase-negative staphylococci to the herd bulk milk somatic cell count

1990 ◽  
Vol 14 (3) ◽  
pp. 193-198 ◽  
Author(s):  
P. Rainard ◽  
M. Ducelliez ◽  
B. Poutrel
2004 ◽  
Vol 52 (2) ◽  
pp. 173-183 ◽  
Author(s):  
Sz. Jánosi ◽  
Zs. Baltay

In a survey of about 3000 dairy cows producing low somatic cell count (SCC) milk and kept on a large-scale dairy farm, California Mastitis Test (CMT) positivity was found in 2714 udder quarters of 1491 cows. Pathogenic microorganisms were isolated from 57.6% of these 2714 udder quarters during bacteriological examination. The commonest pathogens were coagulase-negative staphylococci (CNS, 41%) and Staphylococcus aureus (32.5%); however, udder infections caused by environmental streptococci (12.8%) and coliform bacteria (6.8%) were also common. All pathogens resulted in a significant increase of the SCC in individual bulk milk (IBM) samples. In the case of CNS, this SCC elevation in IBM was significantly lower than in the case of infection by the other pathogens. In spite of this, because of the high number of udder infections caused by CNS, the adverse effect exerted by CNS on dairy herds is considered to be substantial. It was found that 54.6% of all CMT-positive cows produced IBM of an SCC below 400 thousand per ml. The milk produced by 41% of the 315 cows excreting S. aureus also had an SCC below 400 thousand per ml. This poses a serious risk of infection to the healthy herdmates. At the same time, 11% of the infected cows produced IBM with an SCC below 100 thousand per ml. On the basis of these findings, only the regular analysis of SCC of IBM can be a reliable indicator of chronic intramammary infection. As the SCC of milk produced by CMT-positive cows (and especially of those excreting pathogens) tended to increase with advancing lactation, the authors suggest that an efficient drying-off therapy should be used to restore udder health and, whenever justified, culling of cows cannot be avoided either.


2013 ◽  
Vol 109 (1-2) ◽  
pp. 148-151 ◽  
Author(s):  
Jozef Laureyns ◽  
Sofie Piepers ◽  
Stefaan Ribbens ◽  
Steven Sarrazin ◽  
Sarne De Vliegher ◽  
...  

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.


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.


2009 ◽  
Vol 76 (4) ◽  
pp. 490-496 ◽  
Author(s):  
Jan Lievaart ◽  
Herman W Barkema ◽  
Henk Hogeveen ◽  
Wim Kremer

Bulk milk somatic cell count (BMSCC) is a frequently used parameter to estimate the subclinical mastitis prevalence in a dairy herd, but it often differs considerably from the average SCC of all individual cows in milk. In this study, first the sampling variation was determined on 53 dairy farms with a BMSCC ranging from 56 000 to 441 000 cells/ml by collecting five samples on each farm of the same bulk tank. The average absolute sampling variation ranged from 1800 to 19 800 cells/ml. To what extent BMSCC represents all lactating cows was evaluated in another 246 farms by comparing BMSCC to the average herd SCC corrected for milk yield (CHSCC), after the difference was corrected for the sampling variation of BMSCC. On average BMSCC was 49 000 cells/ml lower than CHSCC, ranging from −10 000 cells/ml to 182 000 cells/ml, while the difference increased with an increasing BMSCC. Subsequently, management practices associated with existing differences were identified. Farms with a small (<20%) difference between BMSCC and CHSCC administered intramuscular antibiotics for the treatment of clinical mastitis more often, used the high SCC history when cows were dried off more frequently and had a higher number of treatments per clinical mastitis case compared with farms with a large (⩾20%) difference. Farms feeding high-SCC milk or milk with antibiotic residues to calves were 2·4-times more likely to have a large difference. Although sampling variation influences the differences between BMSCC and CHSCC, the remaining difference is still important and should be considered when BMSCC is used to review the average herd SCC and the subclinical mastitis prevalence.


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.


2015 ◽  
Vol 98 (6) ◽  
pp. 3741-3753 ◽  
Author(s):  
D.A. Shock ◽  
S.J. LeBlanc ◽  
K.E. Leslie ◽  
K. Hand ◽  
M.A. Godkin ◽  
...  

1980 ◽  
Vol 47 (3) ◽  
pp. 393-400 ◽  
Author(s):  
Ali E. Ali ◽  
Anthony T. Andrews ◽  
Gordon C. Cheeseman

SummaryThe effects of increased somatic cell count, whether caused by infection or by experimental infusion of bacterial endotoxin, on the distribution in milk of caseins between the micellar and soluble forms were investigated. The relationship of somatic cell count to some cheese-making parameters was also studied. With quite modestly elevated cell counts (2–3 × 106/ml) increases of up to 37% in total casein in the soluble phase were observed, most of which was contributed by β-casein, while κ- and αs1-caseins increased only slightly. With storage at 4°C, the concentrations of all the caseins, Ca and phosphate in the soluble phase increased substantially during the first 48 h, but this was followed by a slight decline on further storage. Rennet clotting time, losses of fat in whey, curd moisture, and losses in curd yield and rigidity were all greater the higher the somatic count. Clear differences were detectable in these parameters between milks of very low cell count (e.g. 5 × 104 cells/ml) and milks with counts more typical of those found in bulk supplies (e.g. about 5 × 105 cells/ml). If these findings can be reproduced in commercial practice even a modest reduction in bulk milk somatic cell counts might be expected to bring definite benefits.


Sign in / Sign up

Export Citation Format

Share Document