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de Geus Y, Scherpenisse P, Smit LAM, Bossers A, Stegeman JA, Benedictus L, Spieß L, Koop G. Total bacterial count and somatic cell count in bulk and individual goat milk around kidding: two longitudinal observational studies. J Dairy Sci 2024:S0022-0302(24)00742-2. [PMID: 38608959 DOI: 10.3168/jds.2023-24574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2023] [Accepted: 03/05/2024] [Indexed: 04/14/2024]
Abstract
Total bacterial count (TBC) and somatic cell count (SCC) are important quality parameters in goat milk. Exceeding the bulk milk TBC (BMTBC) thresholds leads to price penalties for Dutch dairy goat farmers. Controlling these milk quality parameters can be challenging, especially around kidding. First, we describe the variation and the peaks around kidding of TBC and SCC in census data on Dutch bulk milk over the last 22 years. Second, to explore causes of these elevations, we studied the variation of TBC and SCC in individual goat milk from 3 weeks before to 5 weeks after kidding and their association with systemic response markers interferon-γ (IFN-γ), calprotectin, β-hydroxybutyrate (BHB), body condition score (BCS) and fecal consistency. We visited 4 Dutch dairy goat farms weekly for 10 to 16 weeks around kidding. Some of the goats had been dried off, other goats were milked continuously throughout pregnancy. A total of 1,886 milk samples from 141 goats were collected for automated flowcytometric quantification of TBC and SCC measurement. IFN-γ, calprotectin and BHB were determined twice in blood of the same goats, most samples were collected after kidding. The BCS and fecal consistency were scored visually before and after kidding. We found a strong correlation between TBC and SCC (Spearman's rho = 0.87) around kidding. Furthermore, in the third week before kidding, the average TBC (5.67 log10 cfu/mL) and SCC (6.70 log10 cells/mL) were significantly higher compared with the fifth week after kidding, where the average TBC decreased to 4.20 log10 cfu/mL and the average SCC decreased to 5.92 log10 cells/mL. In multivariable linear regression models, farm and stage of lactation were significantly associated with TBC and SCC, but none of the systemic response markers correlated with TBC or SCC. In conclusion, TBC and SCC in dairy goats were high in late lactation and decreased shortly after parturition. For SCC, the dilution effect might have caused the decrease, but this was not plausible for TBC. Moreover, the excretion of bacteria and cells in goat milk was not associated with the selected systemic response markers that were chosen as a read out for general immunity status, intestinal health and metabolic diseases. Therefore, we assume that the TBC increase before kidding and the decrease after parturition is caused by other systemic, possibly hormonal, processes. To reduce BMTBC and BMSCC, it would be advisable to keep milk of goats with highest numbers of bacteria and cells in their milk out of the bulk milk during end lactation. Further studies are needed to investigate the effects of withholding this end lactation milk from the bulk tank.
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Affiliation(s)
- Y de Geus
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, the Netherlands.
| | - P Scherpenisse
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - L A M Smit
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - A Bossers
- Institute for Risk Assessment Sciences, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - J A Stegeman
- Farm Animal Health, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - L Benedictus
- Farm Animal Health, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, the Netherlands
| | - L Spieß
- Qlip laboratories, 7200 AC Zutphen, the Netherlands
| | - G Koop
- Farm Animal Health, Department of Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, 3584 CM Utrecht, the Netherlands
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Deng Z, Lam TJGM, Hogeveen H, Koop G. Regularly fluctuating somatic cell count pattern in dairy herds. J Dairy Sci 2021; 104:11126-11134. [PMID: 34275629 DOI: 10.3168/jds.2020-20063] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2020] [Accepted: 06/04/2021] [Indexed: 11/19/2022]
Abstract
Online somatic cell count (SCC) measurement is widely used in dairy herds milked with automatic milking systems (AMS) and gives the opportunity to closely monitor individual cow udder health. Using automated SCC data, we observed cows displaying a remarkably regularly fluctuating SCC (rfSCC) pattern, which is described in this study. We aimed to (1) estimate the prevalence of rfSCC in cows milked by AMS, (2) characterize the rfSCC pattern, and (3) identify factors potentially associated with the rfSCC pattern. We analyzed 30-d episodes of composite SCC recordings of 1,000 cows from 55 dairy herds from 6 countries using an AMS with automated SCC measurement, and we identified the rfSCC pattern in 4.7% (95% CI: 3.5-6.2%) of these episodes. The rfSCC episodes had a median SCC of 701 × 1,000 cells/mL (2.5-97.5% quantile: 539-1,162), a median amplitude of 552 × 1,000 cells/mL (2.5-97.5% quantile: 409-886), and a median cycle length of 4.1 d (2.5-97.5% quantile: 3.7-4.9). Bacteriological culture data from quarter-milk samples collected every 2 wk in 1 Dutch AMS herd were analyzed, yielding no clear association between pathogen species and the rfSCC pattern found in that herd. Altogether, we described an intriguing phenomenon, present in almost 5% of the cows during a 1-mo study period. Further work is needed to quantify its importance in terms of udder health, but also to elucidate the mechanism behind this remarkable SCC pattern.
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Affiliation(s)
- Z Deng
- Department Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, the Netherlands.
| | - T J G M Lam
- Department Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, the Netherlands; Royal GD, PO Box 9, 7400 AA Deventer, the Netherlands
| | - H Hogeveen
- Department Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, the Netherlands; Chair Group Business Economics, Wageningen University and Research, PO Box 8130, 6700 EW Wageningen, the Netherlands
| | - G Koop
- Department Population Health Sciences, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, the Netherlands
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Deng Z, Lam T, Hogeveen H, Spaninks M, Heij N, Postema M, van Werven T, Koop G. Antimicrobial use and farmers' attitude toward mastitis treatment on dairy farms with automatic or conventional milking systems. J Dairy Sci 2020; 103:7302-7314. [DOI: 10.3168/jds.2019-17960] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2019] [Accepted: 03/18/2020] [Indexed: 11/19/2022]
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Mekonnen SA, Koop G, Getaneh AM, Lam TJGM, Hogeveen H. Failure costs associated with mastitis in smallholder dairy farms keeping Holstein Friesian × Zebu crossbreed cows. Animal 2019; 13:2650-2659. [PMID: 31094307 DOI: 10.1017/s175173111900082x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
Mastitis is a costly disease and in many areas of the world, these costs have been quantified to support farmers in their decision making with regard to prevention of mastitis. Although for subsaharan circumstances estimates have been made for the costs of subclinical mastitis (SCM), farm-specific cost estimations comprising both clinical mastitis (CM) and SCM are lacking. In this paper, we quantified failure costs of both CM and SCM on 150 Ethiopian market-oriented dairy farms keeping Holstein Friesian × Zebu breed cows. Data about CM were collected by face-to-face interviews and the prevalence of SCM was estimated for each farm using the California mastitis test. All other relevant information needed to calculate the failure costs, such as the consequences of mastitis and price levels, was collected during the farm visits, except for the parameter for milk production losses due to SCM, which was based on literature estimates and subjected to sensitivity analyses. The average total failure costs of mastitis was estimated to be 4 765 Ethiopian Birr (ETB) (1 ETB = 0.0449 USD) per farm per year of which SCM contributed 54% of the costs. The average total failure costs per lactating cow per farm per year were 1 961 ETB, with a large variation between farms (range 0 to 35 084 ETB). This large variation in failure costs between farms was mainly driven by variation in incidence of CM and prevalence of SCM. Milk production losses made the largest contribution (80%), whereas culling contributed 13% to 17% to the total failure costs. In our estimates, costs of veterinary services, drugs, discarded milk and labour made a minor contribution to the total failure costs of mastitis. Relative to the income of dairy farmers in North Western Ethiopia; the total failure costs of mastitis are high. In general, Ethiopian farmers are aware of the negative consequences of CM, but creating awareness of the high costs of SCM and showing large variation between farmers may be instrumental in motivating farmers to also take preventive measures for SCM.
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Affiliation(s)
- S A Mekonnen
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, 3584 CL, Utrecht, The Netherlands
- Department of Veterinary Epidemiology and Public Health, College of Veterinary Medicine and Animal Sciences, University of Gondar, Gondar, Ethiopia
| | - G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, 3584 CL, Utrecht, The Netherlands
| | - A M Getaneh
- Department of Veterinary Laboratory Technology, College of Agriculture and Veterinary Science, Ambo University, Ambo, Ethiopia
| | - T J G M Lam
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, 3584 CL, Utrecht, The Netherlands
- GD Animal Health, 7400 AA Deventer, The Netherlands
| | - H Hogeveen
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, 3584 CL, Utrecht, The Netherlands
- Business Economics Group, Wageningen University, 6700 EW Wageningen, The Netherlands
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Deng Z, Koop G, Lam T, van der Lans I, Vernooij J, Hogeveen H. Farm-level risk factors for bovine mastitis in Dutch automatic milking dairy herds. J Dairy Sci 2019; 102:4522-4535. [DOI: 10.3168/jds.2018-15327] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2018] [Accepted: 01/15/2019] [Indexed: 11/19/2022]
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Hoekstra J, Rutten VPMG, van den Hout M, Spaninks MP, Benedictus L, Koop G. Differences between Staphylococcus aureus lineages isolated from ovine and caprine mastitis but not between isolates from clinical or subclinical mastitis. J Dairy Sci 2019; 102:5430-5437. [PMID: 30981476 DOI: 10.3168/jds.2018-16196] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2018] [Accepted: 02/14/2019] [Indexed: 01/31/2023]
Abstract
Staphylococcus aureus is an important mastitis pathogen, causing both clinical mastitis (CM) and subclinical mastitis (SCM) in small ruminants. In general, CM has a low incidence in sheep and goats but can be very severe and costly. In contrast, subclinical mastitis (SCM) is common but is associated with less cost. For both sheep and goats, S. aureus is the main cause of CM and is associated with SCM cases with a high SCC. Recently, specific lineages of S. aureus have been identified that are associated with CM rather than SCM in dairy cows. It is unknown whether specific S. aureus lineages are associated with CM in goats and sheep. The aim of this study was to compare the clonal complex (CC), staphylococcal protein A (spa) type, leukocidin lukM-lukF' presence, and potential to produce LukMF' in vitro between CM and SCM S. aureus mastitis isolates obtained from sheep and goats. Differences between isolates from different host species were also compared. Ovine (CM, n = 12; SCM, n = 29) and caprine (CM, n = 14; SCM, n = 30) isolates were obtained from 8 sheep flocks and 8 goat herds in the Netherlands. Overall, the isolates belonged to CC133 (85%), CC398 (7%), CC425 (5%), and CC45 (2%). Seventeen spa types were found, including 6 novel types; the predominant types were t2678 (34%), t544 (18%), and t3583 (18%). Although CC133 was dominant among both sheep and goat isolates, spa type CC133/t2678 was associated with ovine isolates, whereas CC133/t544 and CC133/t3583 were found mostly in goats. The presence of lukM-lukF' among the S. aureus isolates was high (87%), especially in CC133 (96%) and CC425 (100%), but the genes were absent in CC45 and CC398. In vitro-cultured lukM-lukF'-positive isolates produced LukM (71 out of 74 positive isolates tested) in the range of 0.4 to 5.0 µg/mL. Interestingly, the goat-associated lineages CC133/t544 and CC133/t3583 produced more LukM in vitro than the sheep-associated CC133/t2678. We found no difference in LukMF' production potential between CM and SCM isolates. In sheep as well as in goats, no association was found between genotype and CM or SCM, demonstrating that the same lineages of S. aureus are responsible for both CM and SCM. These results suggest that subclinically infected animals in a herd or flock likely act as the reservoir of S. aureus causing CM. This highlights the importance of early identification and control of SCM and suggests that controlling SCM within a herd is an effective intervention to prevent CM in small ruminants.
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Affiliation(s)
- J Hoekstra
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands; Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, the Netherlands.
| | - V P M G Rutten
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands; Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort 0110, South Africa
| | - M van den Hout
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands
| | - M P Spaninks
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, the Netherlands
| | - L Benedictus
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL Utrecht, the Netherlands; Division of Infection and Immunity, The Roslin Institute, The University of Edinburgh, Easter Bush, Midlothian EH25 9RG, Scotland
| | - G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, the Netherlands
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Mekonnen SA, Lam TJGM, Hoekstra J, Rutten VPMG, Tessema TS, Broens EM, Riesebos AE, Spaninks MP, Koop G. Characterization of Staphylococcus aureus isolated from milk samples of dairy cows in small holder farms of North-Western Ethiopia. BMC Vet Res 2018; 14:246. [PMID: 30139356 PMCID: PMC6107951 DOI: 10.1186/s12917-018-1558-1] [Citation(s) in RCA: 37] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2018] [Accepted: 07/31/2018] [Indexed: 01/01/2023] Open
Abstract
Background Staphylococcus aureus is a contagious, opportunistic pathogen that causes clinical or subclinical mastitis in dairy cattle. The genetic background and antimicrobial resistance of isolates from Ethiopian dairy farms has not been studied. Therefore, the aim of this study was to characterize S. aureus from Ethiopian hand milked dairy cows, by spa, MLST and virulence factor typing, and by assessment of antimicrobial susceptibility. A total of 79 S. aureus isolates from intramammary infections was studied. A PCR was used to detect lukM-lukF’ and pvl genes encoding the bovine and human associated bi-component leukocidins, and the toxic shock syndrome toxin gene-1 (tst). Antimicrobial susceptibility was determined using the broth microdilution method. Results Twenty different spa types were identified, most isolates were t042 (58%), and the closely related t15786 (11%). The proportion of isolates positive for lukM-lukF’, tst and pvl was low at 0.04, 0.10 and 0.09 respectively, with lukM-lukF’ often co-occurring with tst, but not with pvl. Methicillin-resistance was not found, but resistance to penicillin/ampicillin (86%) and tetracycline (54%) was very common. Conclusions We found a high degree of relatedness among bovine S. aureus isolates in North-Western Ethiopia, suggesting contagious within and between farm transmission of strains that are often resistant to commonly used antimicrobials. This highlights the need for effective preventive measures that aim at limiting transmission of bacteria rather than using antimicrobials to control S. aureus mastitis in Ethiopia. Electronic supplementary material The online version of this article (10.1186/s12917-018-1558-1) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- S A Mekonnen
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584, CL, Utrecht, The Netherlands. .,Faculty of Veterinary Medicine, University of Gondar, P.O. Box 196, Gondar, Ethiopia.
| | - T J G M Lam
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584, CL, Utrecht, The Netherlands.,GD Animal Health, P.O. Box 9, 7400 AA, Deventer, The Netherlands
| | - J Hoekstra
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584, CL, Utrecht, The Netherlands.,Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, The Netherlands
| | - V P M G Rutten
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, The Netherlands.,Department of Veterinary Tropical Diseases, Faculty of Veterinary Science, University of Pretoria, Private Bag X04, Onderstepoort, Pretoria, 0110, South Africa
| | - T S Tessema
- Institute of Biotechnology, Addis Ababa University, P.O. Box 1176, Addis Ababa, Ethiopia
| | - E M Broens
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, The Netherlands
| | - A E Riesebos
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584, CL, Utrecht, The Netherlands
| | - M P Spaninks
- Department of Infectious Diseases and Immunology, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 1, 3584 CL, Utrecht, The Netherlands
| | - G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584, CL, Utrecht, The Netherlands
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Rainard P, Foucras G, Fitzgerald JR, Watts JL, Koop G, Middleton JR. Knowledge gaps and research priorities in Staphylococcus aureus mastitis control. Transbound Emerg Dis 2017; 65 Suppl 1:149-165. [PMID: 28984427 DOI: 10.1111/tbed.12698] [Citation(s) in RCA: 94] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Indexed: 12/31/2022]
Abstract
This study assessed knowledge gaps and suggested research priorities in the field of Staphylococcus aureus mastitis. Staphylococcus aureus infecting the mammary gland remains a major problem to the dairy industry worldwide because of its pathogenicity, contagiousness, persistence in the cow environment, colonization of skin or mucosal epithelia, and the poor curing efficacy of treatments. Staphylococcus aureus also constitutes a threat to public health due to food safety and antibiotic usage issues and the potential for bidirectional transmission of strains between humans and dairy animals (cows and small ruminants). Gaps have been identified in (i) understanding the molecular basis for pathogenesis of S. aureus mastitis, (ii) identifying staphylococcal antigens inducing protection and (iii) determining the cell-mediated immune responses to infection and vaccination. The recommended priorities for research are (i) improved diagnostic methods for early detection of infection and intervention through treatment or management, (ii) development of experimental models to investigate the strategies used by S. aureus to survive within the mammary gland and resist treatment with anti-microbials, (iii) investigation of the basis for cow-to-cow variation in response to S. aureus mastitis, (iv) identification of the immune responses (adaptive and innate) induced by infection or vaccination and (v) antibacterial discovery programmes to develop new, more effective, narrow spectrum antibacterial agents for the treatment of S. aureus mastitis. With the availability and ongoing improvement of molecular research tools, these objectives may not be out of reach in the future.
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Affiliation(s)
- P Rainard
- ISP, INRA, Université de Tours, UMR1282, Nouzilly, France
| | - G Foucras
- IHAP, Université de Toulouse, INRA, ENVT, Toulouse, France
| | - J R Fitzgerald
- The Roslin Institute, University of Edinburgh, Edinburgh, UK
| | - J L Watts
- Zoetis, External Innovation-Anti-Infectives, VMRD, Kalamazoo, MI, USA
| | - G Koop
- Veterinary Medicine, University of Utrecht, Utrecht, The Netherlands
| | - J R Middleton
- Department of Veterinary Medicine and Surgery, University of Missouri, Columbia, MO, USA
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Mekonnen SA, Koop G, Melkie ST, Getahun CD, Hogeveen H, Lam TJGM. Prevalence of subclinical mastitis and associated risk factors at cow and herd level in dairy farms in North-West Ethiopia. Prev Vet Med 2017; 145:23-31. [PMID: 28903872 DOI: 10.1016/j.prevetmed.2017.06.009] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/24/2016] [Revised: 06/17/2017] [Accepted: 06/19/2017] [Indexed: 11/18/2022]
Abstract
Knowledge of mastitis pathogens and their predominance as well as understanding of risk factors are prerequisites to improve udder health in a herd, region or country. In Ethiopia, such information is scarce, despite the fact that mastitis is an important cattle disease in the country. A cross-sectional study that describes prevalence and causative agents of subclinical mastitis (SCM) as well as risk factors at cow and herd level was conducted on 167 dairy farms in North-West Ethiopia. On average, 33% of the quarters and 62% of the cows were California Mastitis Test (CMT) positive, but the within herd quarter level prevalence ranged between 0 and 100%. A total of 1543 milk samples, being 27 quarters that showed signs of CM, 606 CMT positive quarters and 910 CMT negative quarters were cultured, respectively 40%, 67% and 47% was positive on bacteriological culture. Coagulase negative staphylococci (CNS) (31%) followed by Staphylococcus aureus (9%) were the pathogens most frequently isolated. Based on face-to-face questionnaire data, 35 herd level and 13 cow level factors were evaluated for their association with SCM (based on CMT) and with a positive culture for any bacteria, CNS or S. aureus. Cows with a history of CM, of higher parity, >150days in milk (DIM) and herds with owners that have >10th grade level of education had higher odds of SCM. The odds of being culture positive for any bacteria was higher in cows with ≥25% Holstein Friesian blood level (HBL), >150 DIM, housed on cemented floors, and milked by squeezing rather than stripping. Similarly, the odds of culturing CNS was higher in cows with 25-50% HBL, >150 DIM, and milked by squeezing. Staphylococcus aureus was more often found in cows with a history of CM and in larger herds. Checking the udder for mastitis, feeding cows according to their requirements and allowing calves to suckle the cows were negatively associated with SCM, with culturing any bacteria and with culturing CNS, respectively. Higher odds of SCM and of culturing CNS were found in herds owned by members of a dairy cooperative. In summary, we identified a high prevalence of SCM and intramammary infections with substantial variation between farms, and we found a number of risk factors explaining this variation. The risk factors for mastitis that were identified in this study can form the basis of an udder health control program specific for the dairy industry in North-West Ethiopia.
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Affiliation(s)
- S A Mekonnen
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL, Utrecht, The Netherlands; Faculty of Veterinary Medicine, University of Gondar, P.O. Box 196, Gondar, Ethiopia.
| | - G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL, Utrecht, The Netherlands
| | - S T Melkie
- School of Veterinary Medicine, Wollo University, P.O. Box 1145, Dessie, Ethiopia
| | - C D Getahun
- Sheno Agricultural Research Center, P.O. Box 112, Debre Berhan, Ethiopia
| | - H Hogeveen
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL, Utrecht, The Netherlands; Business Economics Group, Wageningen University, P.O. Box 8130, 6700 EW, Wageningen, The Netherlands
| | - T J G M Lam
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL, Utrecht, The Netherlands; GD Animal Health, P.O. Box 9, 7400 AA, Deventer, The Netherlands
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Koop G, van Werven T, Roffel S, Hogeveen H, Nazmi K, Bikker F. Short communication: Protease activity measurement in milk as a diagnostic test for clinical mastitis in dairy cows. J Dairy Sci 2015; 98:4613-8. [DOI: 10.3168/jds.2014-8746] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2014] [Accepted: 04/01/2015] [Indexed: 11/19/2022]
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Monger VR, Stegeman JA, Koop G, Dukpa K, Tenzin T, Loeffen WLA. Seroprevalence and associated risk factors of important pig viral diseases in Bhutan. Prev Vet Med 2014; 117:222-32. [PMID: 25081946 DOI: 10.1016/j.prevetmed.2014.07.005] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2014] [Revised: 07/04/2014] [Accepted: 07/05/2014] [Indexed: 10/25/2022]
Abstract
A cross-sectional serological study was conducted in Bhutan between October 2011 and February 2012 to determine the prevalence of antibodies to classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), swine influenza virus (SIV) subtype H1N1 and Aujeszky's disease virus (ADV). Furthermore, risk factors for the seropositive status were investigated. Antibodies to SIV, subtype H1N1 (likely pandemic H1N1 2009) were detected in 49% of the pigs in the government farms, and 8% of the village backyard pigs. For PCV2, these percentages were 73% and 37% respectively. For CSFV, the percentages were closer together, with 62% and 52% respectively. It should be taken into consideration that vaccination of piglets is routine in the government herds, and that piglets distributed to backyard farms are also vaccinated. No direct evidence of CSFV infections was found, either by clinical signs or virus isolation. Antibodies to PRRSV and Aujeszky's disease, on the other hand, were not found at all. Risk factors found are mainly related to practices of swill feeding and other biosecurity measures. For CSFV, these were swill feeding (OR=2.25, 95% CI: 1.01-4.99) and contact with neighbour's pigs (OR=0.31, 95% CI: 0.13-0.75). For PCV2 this was lending of boars for local breeding purposes (OR=3.30, 95% CI: 1.43-7.59). The results of this study showed that PCV2 and SIV infections are important in pigs in Bhutan and thus appropriate control strategies need to be designed and applied which could involve strict regulation on the import of live pigs and vaccination against these diseases.
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Affiliation(s)
- V R Monger
- Central Veterinary Institute of Wageningen UR, Department of Virology, P.O. Box 65, 8200 AB Lelystad, The Netherlands; National Centre for Animal Health, Department of Livestock, Ministry of Agriculture and Forests, Thimphu, Bhutan.
| | - J A Stegeman
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, The Netherlands
| | - G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, 3584 CL Utrecht, The Netherlands
| | - K Dukpa
- National Centre for Animal Health, Department of Livestock, Ministry of Agriculture and Forests, Thimphu, Bhutan
| | - T Tenzin
- National Centre for Animal Health, Department of Livestock, Ministry of Agriculture and Forests, Thimphu, Bhutan
| | - W L A Loeffen
- Central Veterinary Institute of Wageningen UR, Department of Virology, P.O. Box 65, 8200 AB Lelystad, The Netherlands
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12
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Koop G, De Vliegher S, De Visscher A, Supré K, Haesebrouck F, Nielen M, van Werven T. Differences between coagulase-negative Staphylococcus species in persistence and in effect on somatic cell count and milk yield in dairy goats. J Dairy Sci 2013; 95:5075-5084. [PMID: 22916911 DOI: 10.3168/jds.2012-5615] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/12/2012] [Accepted: 05/20/2012] [Indexed: 11/19/2022]
Abstract
Coagulase-negative staphylococci (CNS) are the most commonly isolated bacteria from goat milk. The goal of this study was to explore and describe differences between CNS species in persistence of intramammary infection (IMI) and in effect on somatic cell count (SCC) and milk yield (MY). Milk samples were collected from 530 does from 5 Dutch dairy goat herds on 3 occasions during 1 lactation. Coagulase-negative staphylococci species were identified at the species level by transfer RNA-intergenic spacer PCR (tDNA-PCR) followed by capillary electrophoresis. The most prevalent CNS species were Staphylococcus caprae, Staphylococcus epidermidis, Staphylococcus simulans, and Staphylococcus xylosus, but large differences were seen in species distribution between herds. Staphylococcus caprae and Staph. xylosus appeared to be more persistent than other species, but confidence intervals were overlapping. The effect of IMI caused by the 4 most prevalent CNS species on SCC and on MY was determined with linear regression models, and Staph. aureus and Corynebacterium bovis were included in the analyses as reference organisms. Most species were associated with a significantly higher SCC than noninfected udder halves, but the effect of CNS species on SCC was much smaller than the effect of Staph. aureus on SCC. We found a significant positive association between infection with Staph. caprae and MY. Intramammary infection caused by Staph. xylosus, on the other hand, had a negative association with milk yield, comparable to the effect of Staph. aureus, but these effects were not significantly different from zero. Intramammary infections with CNS species have a high prevalence in goats and are persistent, but have a limited effect on SCC compared with IMI with Staph. aureus. The effect of CNS species on MY differed between species, but differences were nonsignificant because limited numbers per species were available for analysis. Therefore, CNS species appear to behave as minor pathogens in goats, but larger studies are needed to give better estimates for the effect on MY.
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Affiliation(s)
- G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, 3584 CL, the Netherlands.
| | - S De Vliegher
- M-Team and Mastitis and Milk Quality Research Unit, Department of Reproduction, Obstetrics, and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, B-9820, Belgium
| | - A De Visscher
- M-Team and Mastitis and Milk Quality Research Unit, Department of Reproduction, Obstetrics, and Herd Health, Faculty of Veterinary Medicine, Ghent University, Merelbeke, B-9820, Belgium
| | - K Supré
- Milk Control Center Flanders, Lier, B-2500, Belgium
| | - F Haesebrouck
- Department of Pathology, Bacteriology, and Avian Diseases, Faculty of Veterinary Medicine, Ghent University, Merelbeke, B-9820, Belgium
| | - M Nielen
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, 3584 CL, the Netherlands
| | - T van Werven
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, 3584 CL, the Netherlands
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13
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Koop G, De Visscher A, Collar CA, Bacon DAC, Maga EA, Murray JD, Supré K, De Vliegher S, Haesebrouck F, Rowe JD, Nielen M, van Werven T. Short communication: Identification of coagulase-negative staphylococcus species from goat milk with the API Staph identification test and with transfer RNA-intergenic spacer PCR combined with capillary electrophoresis. J Dairy Sci 2012; 95:7200-5. [PMID: 23040022 DOI: 10.3168/jds.2012-5747] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2012] [Accepted: 08/12/2012] [Indexed: 11/19/2022]
Abstract
Coagulase-negative staphylococci (CNS) are the most commonly isolated bacteria from goat milk, but they have often been identified with phenotypic methods, which may have resulted in misclassification. The aims of this paper were to assess the amount of misclassification of a phenotypic test for identifying CNS species from goat milk compared with transfer RNA intergenic spacer PCR (tDNA-PCR) followed by capillary electrophoresis, and to apply the tDNA-PCR technique on different capillary electrophoresis equipment. Milk samples were collected from 416 does in 5 Californian dairy goat herds on 3 occasions during lactation. In total, 219 CNS isolates were identified at the species level with tDNA-PCR and subjected to the API 20 Staph identification test kit (API Staph; bioMérieux, Durham, NC). If the same species was isolated multiple times from the same udder gland, only the first isolate was used for further analyses, resulting in 115 unique CNS isolates. According to the tDNA-PCR test, the most prevalent CNS species were Staphylococcus epidermidis, Staphylococcus caprae, and Staphylococcus simulans. Typeability with API staph was low (72%). Although the API Staph test was capable of identifying the majority of Staph. epidermidis and Staph. caprae isolates, sensitivity for identification of Staph. simulans was low. The true positive fraction was high for the 3 most prevalent species. It was concluded that the overall performance of API Staph in differentiating CNS species from goat milk was moderate to low, mainly because of the low typeability, and that genotypic methods such as tDNA-PCR are preferred.
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Affiliation(s)
- G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, the Netherlands.
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14
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Koop G, van Werven T, Toft N, Nielen M. Estimating test characteristics of somatic cell count to detect Staphylococcus aureus-infected dairy goats using latent class analysis. J Dairy Sci 2011; 94:2902-11. [DOI: 10.3168/jds.2010-3929] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2010] [Accepted: 02/14/2011] [Indexed: 11/19/2022]
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15
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Affiliation(s)
- G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Yalelaan 7, Utrecht, The Netherlands.
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16
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Koop G, van Werven T, Schuiling H, Nielen M. The effect of subclinical mastitis on milk yield in dairy goats. J Dairy Sci 2010; 93:5809-17. [DOI: 10.3168/jds.2010-3544] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2010] [Accepted: 09/10/2010] [Indexed: 11/19/2022]
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17
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Koop G, Dik N, Nielen M, Lipman LJA. Short communication: Repeatability of differential goat bulk milk culture and associations with somatic cell count, total bacterial count, and standard plate count. J Dairy Sci 2010; 93:2569-73. [PMID: 20494165 DOI: 10.3168/jds.2009-2705] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2009] [Accepted: 03/09/2010] [Indexed: 11/19/2022]
Abstract
The aims of this study were to assess how different bacterial groups in bulk milk are related to bulk milk somatic cell count (SCC), bulk milk total bacterial count (TBC), and bulk milk standard plate count (SPC) and to measure the repeatability of bulk milk culturing. On 53 Dutch dairy goat farms, 3 bulk milk samples were collected at intervals of 2 wk. The samples were cultured for SPC, coliform count, and staphylococcal count and for the presence of Staphylococcus aureus. Furthermore, SCC (Fossomatic 5000, Foss, Hillerød, Denmark) and TBC (BactoScan FC 150, Foss) were measured. Staphylococcal count was correlated to SCC (r=0.40), TBC (r=0.51), and SPC (r=0.53). Coliform count was correlated to TBC (r=0.33), but not to any of the other variables. Staphylococcus aureus did not correlate to SCC. The contribution of the staphylococcal count to the SPC was 31%, whereas the coliform count comprised only 1% of the SPC. The agreement of the repeated measurements was low. This study indicates that staphylococci in goat bulk milk are related to SCC and make a significant contribution to SPC. Because of the high variation in bacterial counts, repeated sampling is necessary to draw valid conclusions from bulk milk culturing.
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Affiliation(s)
- G Koop
- Department of Farm Animal Health, Faculty of Veterinary Medicine, Utrecht University, Utrecht, The Netherlands.
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18
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Koop G, Nielen M, van Werven T. Bulk milk somatic cell counts are related to bulk milk total bacterial counts and several herd-level risk factors in dairy goats. J Dairy Sci 2009; 92:4355-64. [DOI: 10.3168/jds.2009-2106] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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Koop G, Folz B, Schulze S. [A rare orbital tumor]. Ophthalmologe 2008; 105:774-6. [PMID: 18415109 DOI: 10.1007/s00347-007-1665-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Affiliation(s)
- G Koop
- Zentrum für Augenheilkundedes Universitätsklinikums Giessen und Marburg GmbH,Standort Marburg, Robert-Koch-Strasse 4, 35037, Marburg, Deutschland.
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Koop G, Gräf M. Steele-Richardson-Olszewski-Syndrom - Darstellung eines selten erkannten Krankheitsbildes anhand zweier Fallberichte. Klin Monbl Augenheilkd 2007; 224:799-803. [DOI: 10.1055/s-2007-963605] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Schulze S, Koop G, Strempel I. [Unexpected foreign bodies in eyelid surgery. Three cases of unexplained lid tumors]. Ophthalmologe 2007; 104:594-7. [PMID: 17431637 DOI: 10.1007/s00347-006-1472-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Foreign bodies are quite commonly found incorporated in the lid area after injuries. Normally the patient's description of the injury and the usually fresh clinical findings leave little room for doubt about their composition. In isolated cases, however, patients are admitted with "lid tumors" following an accident in the rather distant past, so that sometimes no connection can be seen with the symptoms present on admission and it is not even clear whether there is still foreign material in the wound. Subcutaneous swellings can then easily be mistaken for cicatricial tissue, granulomas or old hematomas. In all these cases there can be a big difference between what the surgeon expects and the actual intraoperative findings. We present three cases in which unexpected foreign bodies have been extracted from the eyelid region.
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Affiliation(s)
- S Schulze
- Augenklinik des Universitätsklinikums Giessen und Marburg GmbH, Standort Marburg, Robert-Koch-Strasse 4, 35033 Marburg, Deutschland.
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Wijnker JJ, Koop G, Lipman LJA. Antimicrobial properties of salt (NaCl) used for the preservation of natural casings. Food Microbiol 2006; 23:657-62. [PMID: 16943065 DOI: 10.1016/j.fm.2005.11.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2005] [Accepted: 11/20/2005] [Indexed: 11/28/2022]
Abstract
The antimicrobial properties of salt (NaCl) used for the preservation of natural casings were studied by investigating the survival of six bacterial species in natural casings at different water activity (aw) levels. Individual sheep casings were inoculated with ca. 10(5) colony-forming units (cfu) g(-1) of Escherichia coli, Salmonella typhimurium, Listeria monocytogenes, Staphylococcus aureus, Clostridium perfringens and 10(2)cfu g(-1) of E. coli O157:H7. The casings were stored at 20+/-1.5 degrees C in different brines and dry salt, giving aw-levels of 0.90 aw, 0.87aw, 0.85 aw, 0.83 aw and 0.75 aw. Samples were taken at day 1, 3, 6, 8, 13, 20, 27 and 30 after inoculation and the number of bacteria present was determined. Based on survival curves, death rates (day(-1)) were calculated to quantify the reduction in log10 cfu g(-1) per day. The influence of aw on death rates was higher for Gram-negative bacteria than for Gram-positive bacteria. The death rates were overall higher for Gram-negatives than for Gram-positives. No clear reduction in the survival of C. perfringens in relation to any aw level was observed in this study. These results indicate that the antimicrobial properties of salt used for the preservation of natural casings are sufficient to reduce the bacterial contamination (except for Clostridium spores) well below acceptable levels at a water activity level of 0.85 or lower during a 30-day storage period.
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Affiliation(s)
- J J Wijnker
- Van Hessen bv, Nieuwerkerk a/d IJssel, The Netherlands
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Abstract
BACKGROUND Ocular neuromyotonia is a rare ocular motility disorder characterized by involuntary contractions of one or several ocular motor muscles. In this report a typical case is presented. PATIENT AND METHODS A 61-year-old female patient was referred with persistent diplopia despite previous surgical treatment for right 6 (th) nerve palsy. The palsy was caused by a meningeoma of the petrous bone, which had been incompletely resected. Subsequently, the patient had received radiation therapy. Strabismological and neuroophthalmological examinations were performed. The results coincide with data collected in our department from three other patients with ocular neuromyotonia (2 cranial nerve VI, 1 cranial nerve IV), over the past three years. RESULTS The patient showed orthophoria at distance (5 m) and an exophoria of 6 degrees at near vision. The abduction and adduction of the right eye were restricted to 40 degrees and 35 degrees , respectively. After several seconds of eccentric gaze to the right, the right eye remained in an abducted position of approximately 25 degrees . The gaze to the left led to a retraction instead of an adduction of the right eye. The spasm of the lateral rectus muscle resolved after some seconds, returning to the aforementioned right eye motility. Under oral treatment with carbamazepine, initially 200 mg, later increasing to 400 mg per day, the symptoms improved significantly, did not resolve entirely, however. CONCLUSIONS These typical findings permit the diagnosis of ocular neuromyotonia. The characteristic symptoms of ocular neuromyotonia and the typical history of a previous intracranial tumor, treated neurosurgically with adjuvant radiotherapy, lead to the hypothesis that ephaptic transmission in the cranial nerve is the underlying pathophysiological mechanism in the development of ocular neuromyotonia. Hereby, efferent impulses from non-twitch motoneurons could activate neighbouring axons, and spread both peripherally and centrally. Beside other mechanisms discussed, an involvement of proprioceptive elements and their reafference is also a possible cause for the prolonged muscle contraction.
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Affiliation(s)
- G Koop
- Zentrum für Augenheilkunde der Justus-Liebig-Universität Giessen.
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Abstract
Data used in quantitative studies of global tropical deforestation are typically of poor quality. These studies use either cross-sectional or panel data to measure the contribution of social and land use factors to forest decline world wide. However, there are pitfalls in the use of either type of data. Panel data studies treat each year's observation as a distinct, reliable, data point, when a careful examination of the data reveals this assumption to be implausible. In contrast, cross-sectional studies discard most of the time series information in the data, calculating a single average deforestation rate for each country. In this paper, we argue for a middle road between these two approaches: one that does not treat the time series information as completely reliable but does not disregard it altogether. Using a well-known global forest data set (FAO's Production Series Yearbooks), we argue that the most the data can reliably tell us is whether a country's deforestation rate falls into one of four categories or country 'path choices'. We then use the data categorised in this way in a small empirical investigation of the socio-economic causes of deforestation. This multinomial logit framework allows for the determination of the influence of independent variables on the probability that a country will follow one deforestation path vs. another. Results from the logit analysis of key social and land use indicators chosen for their importance in the literature in driving deforestation suggest that the effect of these variables will differ for countries depending on the particular set of deforestation trajectories in question.
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Affiliation(s)
- G Koop
- Department of Economics, University of Glasgow, Glasgow G12 8RT
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