Risk factors associated with the occurrence of multiresistant Staphylococcus spp. isolated from bovine subclinical mastitis in northern Brazil

Staphylococcus bacteria are often associated with subclinical bovine mastitis. This study aimed to identify multiresistant Staphylococcus spp. associated with subclinical mastitis and the associated risk factors. Twenty-three dairy farms with a history of decrease in milk production, located in the lower Acre region, Brazil, were selected. An epidemiological questionnaire was provided in all farms. All animals were examined using the California Mastitis Test (CMT) and their milk samples were collected for bacterial culture. After isolation and identification, the disk diffusion antimicrobial susceptibility test was performed against nine classes of antimicrobials. Of the 339 cows examined using the CMT, 108 had mastitis. A total of 229 milk samples were collected from individual teats. MALDI-TOF MS found isolates belonging to eight species of Staphylococcus, in 101 of these samples. S. chromogenes (58.4%) demonstrated strongest resistance to the nine classes of antimicrobial active principles. Nineteen isolates with multidrug resistance phenotypic profile were identified. This phenotypic expression indicates wide circulation of resistant genes in this species. The presence of multidrug resistance in Staphylococcus spp. in this study was correlated with lack of water for cleaning the corral, which is a preventive factor, minimizing the transmission and persistence of pathogens in the farms.

Harm to the Well-being of the Udder at the Level of Dairy Farms of Sidi Mhamed Benali Wilaya of Relizane (Algeria)

Background: Among the dairy cattle production problems in Algeria, mastitis rank first in terms of socio-economic impact. Our aim is to identify the state of well-being of the udder in order to manage and control mastitis related problems. Methods: The pH analysis of 177 cow milk samples was performed at two farms located in the Sidi Mhamed Benali region in northwest Algeria associated with an assessment (of the udder’s cleanliness degree, the udder’s position, the teat’s hyperkeratosis lesion and the ITH) out over a period of one year (2020-2021). Result: Analysis of mean (of cleanliness, udder position and ITH) between cold and warm season were significantly different at a value of [(4.11; 2.75); (5.19; 4.11); (56.96; 73.76)] respectively. The paper test revealed that the health of the udder is influenced by any variation in cleanliness and the ITH whose correlation coefficient is equal to 0.72 leading to the appearance of subclinical mastitis during the cold season. While during the hot season the bad milking procedure is incriminated in the appearance of hyperkeratosis lesion at a mean value equal to 1 (smooth ring stage) inducing the appearance of clinical mastitis with p less than 0.05, moreover the cows in first lactation are the most influenced by these elicited factors. In conclusion, monitoring and evaluating the well-being of the udder around the parturition is a tool that allows better prevention of mastitis.

Study of the resistance of cows with mastitis depending on the age of lactation

Relevance. The breeding stock and young cattle in the conditions of industrial technology of animal husbandry experience an increased antigenic load, which leads to disturbances in the immune status and the development of inflammatory processes manifested by endometritis and mastitis, diarrheal and respiratory syndromes. It was relevant to conduct a comprehensive assessment of the immunological reactivity of the animal’s body according to the state of resistance in cattle with clinical and subclinical mastitis, depending on the age of lactation. As a result of complex studies, the specific and nonspecific reactivity of the body of cattle in different periods of lactation was studied.Methods. The object of the study were cows of a black-and-white Holstein breed (n = 450). Groups of animals were formed according to the age of lactation:1st lactation, 2–3rd lactation, 3–4th lactation and for health reasons: clinically healthy animals, with subclinical mastitis and clinical mastitis. Milk samples were taken from cows to count the number of somatic cells, and blood to determine the quantitative content of IgG immunoglobulin and indicators of nonspecific resistance.Results. It was found that with mastitis in cows of different lactation ages, almost identical changes in the immune status were observed. Quantitative determination of IgG levels in animal blood serum is the basis for assessing the immunity of cattle. The immune status in clinically healthy animals was characterized by a higher level of the total amount of IgG immunoglobulin in the blood serum (amounted to 22.25 ± 0.70 mg/ml), whereas in cows with a subclinical form of mastitis, the level of IgG immunoglobulin decreased by 12.3%, with a clinical form of mastitis — by 17.2%. The results also showed that in cows of different lactations with subclinical and clinical mastitis, the bactericidal activity (by 10.8%) and the lysozyme activity of the blood increased significantly (by 8.22%). In cows with clinical mastitis — by 8.6% and 9.7% respectively, compared with the indicators in groups of healthy animals. Thus, mastitis, occurring in acute and subacute form, leads to a decrease in the resistance of the cows’ organism.

Etiology of Mastitis and Antimicrobial Resistance in Dairy Cattle Farms in the Western Part of Romania

The present study aimed to determine the bacteria isolated from bovine mastitis and their antimicrobial resistance in the western part of Romania. Clinical mastitis was diagnosed based on local inflammation in the udder, changes in milk, and when present, generalized symptoms. Subclinical mastitis was assessed using a rapid test—the California Mastitis Test. The identification of bacterial strains was performed based on biochemical profiles using API system tests (API 20 E, API Staph, API 20 Strep, API Coryne, API 20 NE (bioMerieux, Marcy l’Etoile, France), and MALDI-TOF mass spectrometry (MS). The prevalent isolated bacteria were Staphylococcus spp. (50/116; 43.19%), followed by Streptococcus spp. (26/116; 22.41%), E. coli (16/116; 13.79%), Corynebacterium spp. (9/116; 7.75%), Enterococcus spp. (10/116; 8.62%), and Enterobacter spp. (5/116; 4.31%). Phenotype antimicrobial resistance profiling was performed used the disc diffusion method. Generally, Gram-positive bacteria showed low susceptibility to most of the antimicrobials tested, except cephalothin. Susceptibilities to penicillins and quinolones were fairly high in Gram-negative bacteria, whereas resistance was observed to macrolides, aminoglycosides, and tetracyclines. The highest number of isolates were multidrug resistant (MDR), the resistance pathotypes identified including the most frequently antimicrobials used in cow mastitis treatment in Romania.

Prevalence of Bovine Mastitis in the Western Region of Cameroon

Mastitis is the major disease in milking cows causing huge losses to the dairy industry worldwide. It is in view to contribute to the eradication of this pathology that the present study was carried out in cattle farms of the West Region of Cameroon from March 2020 to November 2020. A total of 473 lactating cows of local and improved breeds were screened for mastitis. Screening for clinical and sub-clinical mastitis was based on the observation of clinical signs and on the use of the California Mastitis Test (CMT) respectively. The overall prevalence was 34.88%, among which 9.72% and 25.16% represented clinical and subclinical mastitis respectively. In summary, the factors influencing the occurrence of mastitis were: the divisions surveyed (p<0.001), breed type (p=0.003), age range (p<0,001), farm type (p=0.05), soil type (p<0,001), cleaning frequency (p<0.001), feeding method (p<0.001), hygiene of udder (p=0.05) and stage of lactation (p=0.02). The results obtained allow us to recommend an improvement of the breeding conditions to prevent mastitis, because once mastitis appears in a farm, it becomes very difficult to eradicate it.

Economic Impacts of Clinical and Sub Clinical Mastitis on Dairy Farms

Studies have reported on the economic impacts of clinical and subclinical mastitis on dairy farms. Bovine mastitis is a disorder that affects dairy farms and has a major economic impact. Most of the economic losses are the result of mastitis. Mastitis is an invasive infection that is among the most numerous and highly complicated infections in the dairy sector. Mastitis is one of the most expensive diseases in terms of production losses among animal diseases. Mastitis reduces milk production, changes milk composition, and shortens the productive life of infected cows. Farmers must concentrate on avoiding mastitis infection whilst putting in place and following a mastitis control programed. Bovine mastitis, the most significant disease of dairy herds, has huge effects on farm economics. Mastitis losses are due to reduced milk production, the cost of treatments, and culling. Major factors related to low milk yield could be low genetic potential as well as poor nutritional and managerial approaches. Most of the losses are related to somatic cell count (SCC), which is characterised by an increase in the percentage of milk. Culling costs are the costs of rearing or buying a replacement animal, mostly heifers. Overhead impacts include the replacement animals' lower milk supply effectiveness. The expense of replacing animals prematurely due to mastitis is one of the most significant areas of economic loss.

Preliminary study of homeopathic treatment of subclinical mastitis evaluated through somatic cells count (SCC) and California mastitis test (CMT)

The present paper presents the results of homeopathic treatment of 25 Holstein breed cows aged 3 to 8 years old diagnosed with subclinical mastitis through California Mastitis Test (CMT). Animals were divided into 3 groups according with infection level. A homeopathic complex was developed on the grounds of clinical aspects, including Phosphorus 30x, Phytolacca 30x, Silicea 30x, Sulphur 30x, Belladona 30x, Bryonia alba 30x, Pulsatilla 30x, Calendula 30x and biotherapic of Staphylococcus aureus 200x. The remedy was added to salt and was administered to cattle 100g/cow/day for 75 days. CMT were carried out every 2 weeks to control incidence and severity of mastitis; somatic cells count (SCC) was performed at the beginning and the end of treatment. CMT showed significant improvement in regression of infection level all throughout the study; final SCC showed decrease in 82% of animals, signaling thus efficacy of the homeopathic treatment. Keywords: Subclinical mastitis; Dairy cows; Homeopathy; California Mastitis Test, Somatic Cells Count.  Estudo preliminar do tratamento homeopático da mastite subclínica avaliado por contagem de células somáticas (SCC) e California Mastitis Test (CMT) Resumo Este artigo apresenta os resultados do tratamento homeopático de 25 vacas raça Holstein entre 3 e 8 anos de idade diagnosticadas com mastite subclínica através do California Mastitis Test (CMT). Os animais foram divididos em 3 grupos de acordo com o nível da infecção. Foi preparado um complexo homeopático com base nos achados clínicos, composto de: Phosphorus 30X, Phytolacca 30x, Sulphur 30x, Belladona 30x, Bryonia alba 30x, Silicea 30x, Pulsatilla 30x, Calendula 30x s 30X, Phytolacca 30x, Sulphur 30x, Belladona 30x, Bryonia alba 30x, Silicea 30x, Pulsatilla 30x, Calendula 30x e bioterápico de Staphylococcus aureus 200x. O complexo foi acrescentado no sal e administrado na dose de 100g/vaca/dia. O CMT foi realizado a cada 2 semanas a fim de monitorar a incidéncia e gravidade da mastitie; a contagem de células somáticas (SCC) foi realizada ao início e no final do tratamento. Os valores do CMT mostraram melhora significativa no sentido de regressão do nível da infecção ao longo do estudo; o valor final da SCC diminuiu em 82% dos animais, apontando para a eficácia do tratamento homeopático. Palavras-chave: Mastite subclínica; Vacas leiteiras; Homeopatia; CMT, contagem de células somáticas.  Estudio preliminar del tratamiento homeopático de la mastitis sublínica evaluado mediante recuento de células somáticas (SCC) y California Mastitis Test (CMT) Resumen Este artículo presenta los resultados del tratamiento homeopático de 25 vacas raza Holstein entre 3 e 8 años de edad diagnosticadas com mastitis sucblínica mediante California Mastitis Test (CMT). Los animales fueron divididos en 3 grupos según el nível de la infección. Fue compuesto un complejo homeopático con base en la presentación clínica, incluyendo Phosphorus 30X, Phytolacca 30x, Sulphur 30x, Belladona 30x, Bryonia alba 30x, Silicea 30x, Pulsatilla 30x, Calendula 30x y bioterápico de Staphylococcus aureus 200x. El complejo fue agregado en sal y administrado a los animales en la dosis de 100g/vaca/día. CMT fue realizado cada 2 semanas para monitorizar la incidencia y gravedad de la mastitis; recuento de células somáticas (SCC) fue realizado al inicio y al final del tratamiento. CMT mostró mejoría significativa en el sentido de regresión del nivel de la infección a lo largo del estudio; el valor final del SCC disminuyó en 82% de los animales, apuntando para la eficacia del tratamiento homeopático. Palabras-clave: Mastitis subclínica; Vacas lecheras; Homeopatía; CMT, recuento de células somáticas.  Correspondence author: Zilda Cristiani Gazim, [email protected] How to cite this article: Barzon CD, Medeiros F, Moraes RE, Silva LCM, Massambani C, Takemura OS, Gazim ZC. Preliminary study of homeopathic treatment of subclinical mastitis evaluated through somatic cells count and California mastitis test. Int J High Dilution Res [online]. 2008 [cited YYYY Mmm DD]; 7(24): 147-151. Available from: http://journal.giri-society.org/index.php/ijhdr/article/view/292/364. ÂÂÂ

Antimicrobial Resistance of Streptococcus uberis Isolated from Bovine Mastitis: A Review

Bovine mastitis is one of the common diseases resulting in high economic losses in the dairy industry. Streptococcus uberis, the environmental or contagious pathogen, is one of the most frequently identified bacteria causing clinical and subclinical mastitis. Antimicrobials are commonly used to control bacterial infections in dairy cattle. The emergence of antimicrobial resistance (AMR) bacteria made the treatment of this disease by antimicrobials a challenge. Currently, AMR is a global threat to both human and animal health. This review summarizes the AMR profiles of S. uberis collected worldwide between the years 2000-2020. Most of the studies included in this review were from Europe, Estonia, Canada, Danish, Switzerland and Czech. In general, S. uberis is highly susceptible to β-lactam antimicrobials, whereas resistance to tetracyclines, macrolides, aminoglycosides antimicrobials occurred in most countries. The isolates against most antimicrobials presented an increasing pattern over time. It highlights that monitoring the AMR of S. uberis is crucial to reduce the public health crisis.