Effect of caprine arthritis–encephalitis virus infection on milk cell count and N-acetyl-β–glucosaminidase activity in dairy goats

SummaryBacteriology, somatic cell counts (SCO) and N-acetyl-β-glucosaminidase (NAGase) activity determinations were conducted on milk samples collected from does in three dairy herds with caprine arthritis–encephalitis virus (CAEV) infection. In two herds, CAEV-infected does were more likely to have a subclinical bacterial infection of the udder than CAEV-free does (P < 0·05). Does with CAEV but no bacterial udder infection had significantly greater mean SCO and NAGase activity than CAEV-free does without udder infection (P < 0·01). In two herds, changes in milk SCC and NAGase associated with CAEV infection were similar to those produced by coagulase-negative staphylococcal infections. The findings confirm that indirect indicators of bacterial mastitis infection may have reduced specificity in dairy goat herds with CAEV.

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Relationships between infection with caprine arthritis encephalitis virus, intramammary bacterial infection and somatic cell counts in dairy goats

Veterinary Record ◽

10.1136/vr.148.23.711 ◽

2001 ◽

Vol 148 (23) ◽

pp. 711-714 ◽

Cited By ~ 34

Author(s):

A. Sanchez ◽

A. Contreras ◽

J. C. Corrales ◽

J. C. Marco

Keyword(s):

Bacterial Infection ◽

Somatic Cell ◽

Encephalitis Virus ◽

Dairy Goats ◽

Caprine Arthritis Encephalitis Virus ◽

Somatic Cell Counts ◽

Cell Counts

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A pathogen-specific approach towards udder health management in dairy herds: Using culture and somatic cell counts from routine herd investigations

Onderstepoort Journal of Veterinary Research ◽

10.4102/ojvr.v83i1.1146 ◽

2016 ◽

Vol 83 (1) ◽

Cited By ~ 3

Author(s):

Inge-Marié Petzer ◽

Joanne Karzis ◽

Edward F. Donkin ◽

Edward C. Webb

Keyword(s):

Somatic Cell ◽

Health Management ◽

Bacterial Species ◽

False Negative ◽

Dairy Herds ◽

Udder Health ◽

Somatic Cell Counts ◽

Milk Samples ◽

Negative Results ◽

Cell Counts

A dedicated udder health diagnostic programme was developed and used over a 15-year period in South Africa to analyse milk samples based on microbiological and cytological patterns within various groups and for individual cows and udder quarters in dairy herds. These pathogen-specific analyses are utilised for pro-active improvement and management of udder health in South African commercial dairy herds. The programme acts as a monitoring tool and identifies management areas at risk and individual cows with udder disease and uses both quarter and composite milk samples. Intra-mammary infection (IMI) is a dynamic situation and depending on the time a milk sample is taken, false-negative results may be obtained. A new IMI and an infection that is curing may both have low somatic cell counts (SCCs), masking the true bacterial status. SCC in individual infected udder quarters may differ greatly depending on the causative bacterial species, its pathogenicity, the host immune status and the environmental factors involved. A pathogen-specific udder health approach was followed with repeated herd tests to take account of these udder health dynamics. The results of the herd IMI investigation are applied in practice to assist veterinarians, udder health consultants and managers to make informed and specific detailed decisions at both a herd and on an individual cow basis regarding udder health.

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Outbreak of subclinical mastitis in a flock of dairy goats associated with atypicalStaphylococcus haemolyticus

Journal of Dairy Research ◽

10.1017/s0022029908003646 ◽

2008 ◽

Vol 76 (1) ◽

pp. 1-5 ◽

Cited By ~ 5

Author(s):

Gabriel Leitner ◽

Shlom Sela ◽

Orly Hammer-Muntz ◽

Doni Zivotofsky ◽

Limor Weisblit ◽

...

Keyword(s):

Dairy Cows ◽

Small Ruminants ◽

Subclinical Mastitis ◽

Species Level ◽

Dairy Goat ◽

Dairy Goats ◽

Coagulase Negative Staphylococci ◽

Somatic Cell Counts ◽

Cell Counts ◽

Rdna Sequencing

Staphylococcus haemolyticusis a pathogen frequently isolated from dairy cows and small ruminants. However, it always appears in only a few animals and not as a major pathogen. Recently, in a dairy goat herd of approximately 250 milking animals, 25·6% (46/180 goats) had milk cultures with atypical highly mucoid colonies accompanied by elevated somatic cell counts. The isolates were identified asStaph. haemolyticus. The present study describes the steps used in an attempt to identify the bacterium and to compare it with other coagulase-negative staphylococci (CNS) includingStaph. haemolyticus. Species identification performed with the API STAPH-IDENT 32 kit showed >99·4% identity confirmed by 16S rDNA sequencing tests. Microscopically the atypicalStaph. haemolyticusstrains showed unique cuboidal tetrad clusters reminiscent of those of the genusSarcina. The outbreak caused by an atypical CNS underlines the need for accurate biochemical and genetic methods for ultimate identification of CNS to the species level.

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Infection by caprine arthritis-encephalitis virus in Rio Grande do Norte State

Arquivo Brasileiro de Medicina Veterinária e Zootecnia ◽

10.1590/s0102-09352005000600003 ◽

2005 ◽

Vol 57 (6) ◽

pp. 727-731 ◽

Cited By ~ 10

Author(s):

J.S. Silva ◽

R.S. Castro ◽

C.B. Melo ◽

F.M.C. Feijó

Keyword(s):

Virus Infection ◽

Educational Level ◽

Rio Grande ◽

Mortality Rates ◽

Predisposing Factors ◽

Encephalitis Virus ◽

Morbidity And Mortality ◽

Dairy Goat ◽

Caprine Arthritis Encephalitis Virus ◽

Epidemiologic Survey

The prevalence of caprine arthritis-encephalitis (CAE) infection in dairy goat herds from Rio Grande do Norte State, Brazil, was estimated, and the predisposing factors to the infection were identified. An epidemiologic survey was held to collect information on educational level of the owner and origin of the animals, and on sanitation and vaccination practices, diseases, morbidity and mortality rates in the herds. The prevalence of CAE virus infection was 11%, and CAE was always observed in some goats in all studied municipalities.

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Quantitative estimation of the impact of caprine arthritis encephalitis virus infection on milk production by dairy goats

The Veterinary Journal ◽

10.1016/j.tvjl.2012.12.020 ◽

2013 ◽

Vol 197 (2) ◽

pp. 311-317 ◽

Cited By ~ 37

Author(s):

Bernardo Martínez-Navalón ◽

Cristòfol Peris ◽

Ernesto A. Gómez ◽

Bernat Peris ◽

María Luz Roche ◽

...

Keyword(s):

Virus Infection ◽

Milk Production ◽

Quantitative Estimation ◽

Encephalitis Virus ◽

Dairy Goats ◽

Caprine Arthritis Encephalitis Virus ◽

The Impact

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Use of Total and Differential Somatic Cell Counts to Differentiate Potentially Infected from Potentially Non-infected Quarters and Cows and Between Herds of Various Levels of Infection

Journal of Food Protection ◽

10.4315/0362-028x-43.1.10 ◽

1980 ◽

Vol 43 (1) ◽

pp. 10-14 ◽

Cited By ~ 8

Author(s):

A. H. MEEK ◽

D. A. BARNUM ◽

F. H. S. NEWBOULD

Keyword(s):

Somatic Cell ◽

Somatic Cell Count ◽

Dairy Herds ◽

Bacteriological Examination ◽

Somatic Cell Counts ◽

Milk Samples ◽

Cell Counts ◽

Standard Of Comparison ◽

Bulk Tank ◽

Definition Of

The objective of this study was to ascertain the value of variables measured on bulk tank and composite milk samples as predictors, respectively, of the level of mastitis in herds and individual cows. The standard of comparison was the results obtained by bacteriological examination of the secretion from individual mammary quarters. It was found, whether sampling at the herd or cow level, that of the three variables measured on each sample, namely somatic cell count, percentage of cell volume in channel 8 (includes cells with individual volumes from 89.2 to 178.3 μm3) and presence or absence of Streptococcus agalactiae, that the ability of the first two variables to discriminate (predict) was not significantly improved by the inclusion of the latter variable. Using values for the former two variables as measured on bulk tank milk and collected at the time of quarter sampling, it was possible to correctly classify 45.5% of the study herds into one of the three quarter infection rate categories considered, namely, < 10, 10–25 or > 25%. The percentage of herds correctly classified was increased to over 80% by inclusion of five monthly counts recorded previous to the time of quarter sampling. Using the same two variables but measured on composite milk samples, 79.4% of cows were correctly classified as being either positive or negative when a positive cow was defined as one having at least one positive quarter. The overall percentage of cows correctly classified decreased from 79.4 to 77.9% when an attempt was made to distinguish between negative cows and cows with one positive quarter. However, this overall percentage progressively increased to 92.7% as the definition of a positive cow was changed from one having one positive quarter to one having two, three or four positive quarters. The procedure shows promise for monitoring the level of mastitis infection in either dairy herds or cows but requires further refinement before consideration could be given to its implementation.

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