The determination of mastitis severity at 4-level using Milk physical properties: A deep learning approach via MLP and evaluation at different SCC thresholds.

Current research aims to generate an alternative model to classical methods in the determination of subclinical mastitis at 4 levels (healthy, suspicious, subclinical, and clinical). For this purpose, multilayer perceptron (MLP) artificial neural networks (ANN) was developed as test model. 5 variables from the physical properties of milk somatic cell count (SCC), electrical conductivity (EC), pH, density, and temperature at fore milking (TFM) were included in the model in the classification of mastitis. Model performance was validated on test data (%25) and compared with the multinomial logistic regression (MNLR). MLP model has shown a satisfactory performance with an accuracy of 95.14% and - 141 of AIC score better than the control model (MNLR) of 80.27% and - 133 AIC despite using higher number of parameters (104). Since the main problem is to diagnose subclinical mastitis, which does not cause any visible symptoms, it was important to distinguish between absolute subclinical (suspicious excluded positives) and absolute healthy (suspicious included positives) ones. Therefore, optimum cut-off threshold was evaluated for these two different scenarios with only variable SCC the gold standard indicator of subclinical mastitis and results were compared in the interpretation of model performance. The results show that the 5-variable MLP model exhibits a high sensitivity of 93.22% (AUC = 0.95 for healthy ones) at low cutoff thresholds as well. New studies should provide a better understanding by evaluating economics, sustainability, animal welfare and health aspects together to determine the optimal threshold value.

Association between somatic cell count or morbidity of chronic subclinical mastitis and longevity in dairy herds in Eastern Hokkaido, Japan: a cross-sectional study.

An epidemiological analysis was conducted on production records in Hokkaido, Japan, to investigate the potential association between improved milk quality and longevity outcomes. The study found significant variations in herd somatic cell count levels and chronic subclinical mastitis morbidity based on geographical area and herd size. The analysis also revealed a positive correlation between herd somatic cell count and chronic subclinical mastitis morbidity. Although the hypothesis of a causal link between milk quality and longevity was examined, no such association was found. However, intensive assistance for identified high-risk areas and farms is expected to enhance overall milk quality.

Effect of the type of milking on mammary gland examination in Saanen goats / Efeito do tipo de ordenha sobre o exame da glândula mamária de cabras Saanen

This research evaluated the effect of milking on the physical exam of the mammary gland (MG) and milk examination in Saanen goats. Six properties were selected, four farms were used after evaluation of criteria selection and distributed in two groups according to the milking method: manual or mechanical. The physical examination of MG was performed using the techniques of inspection and palpation, in addition to the examination of the milk by strip cup, California Mastitis Test, somatic cell count, and bacteriological exam. It was possible to detect an association between the milking method with the most of physical exam of the MG: inspection of the MG (p = 0.001), inspection of the teat (p = 0.002), palpation of the MG (p = 0.054) and palpation of the teat (p = 0.036). The machine milking had an association with the reduction of the volume of MG (OR = 6.00), reduction of the teat size (OR = 16.19), and firm consistency of mammary parenchyma (OR = 2.39). The use of machine milking represented a less risk for an increase of the volume of the MG volume (OR = 0.288) and the presence of cisternitis (OR = 0.490). The association between the SCC and the type of milking was also detected (p = 0.002). Machine milking was associated with changesin the physical exam of MG and milk examination compatible with traumatic lesions. This information indicates inappropriate use of milking equipment in the dairy goat's properties.(AU)

Esta pesquisa avaliou o efeito da ordenha sobre o exame físico da glândula mamária (GM) e do leite em cabras Saanen. Seis propriedades foram selecionadas, quatro fazendas foram utilizadas após avaliação da seleção dos critérios e distribuídas em dois grupos de acordo com o método de ordenha: manual ou mecânico. O exame físico da GM foi realizado utilizando as técnicas de inspeção e palpação, além do exame do leite pelo teste da caneca de fundo escuro, California Mastitis Test, contagem de células somáticas e exame bacteriológico. Foi possível detectar uma associação entre o método de ordenha com a maioria dos exames físicos da GM: inspeção da GM (p = 0,001), inspeção do teto (p = 0,002), palpação da GM (p = 0,054) e palpação do teto (p = 0,036). A ordenha mecânica associou-se com a redução do volume de GM (OR = 6,00), redução do tamanho do teto (OR = 16,19) e consistência firme do parênquima mamário (OR = 2,39). O uso da ordenha mecânica representou menor risco para o aumento do volume do volume da GM (OR = 0,288) e presença da cisternite (OR = 0,490). Também foi detectada a associação entre a CCS e o tipo de ordenha (p = 0,002). A ordenha mecânica foi associada com as alterações no exame físico de GM e do leite compatíveis com lesões traumáticas. Essas informações indicam o uso inadequado do equipamento de ordenha na criação de cabras leiteiras.(AU)

Evaluation of effects of Mycoplasma mastitis on milk composition in dairy cattle from South Australia.

BACKGROUND: Mycoplasma mastitis is increasingly posing significant impact on dairy industry. Although the effects of major conventional mastitis pathogens on milk components has been widely addressed in the literature, limited data on the effects of different Mycoplasma and Acholeplasma spp. on milk quality and quantity is available. The aim of this study was to determine the casual relationship of Mycoplasma spp. and A. laidlawii to mastitis and compare them to subclinical mastitis caused by conventional mastitis pathogens from a single dairy herd in South Australia; Mycoplasma spp. and A. laidlawii were detected using PCR applied directly to milk samples. The herd had mastitis problem with high somatic cell count and low response rate to conventional antimicrobial therapy. A total of 288 cow-level milk samples were collected aseptically and used in this study. RESULTS: Conventional culture showed a predominance of coagulase-negative staphylococci, followed by coagulase-positive staphylococci, Streptococcus spp., Enterococcus spp., E. coli, and Klebsiella spp. PCR results showed a high prevalence of mycoplasmas (76.7%), including A. laidlawii (10.8%), M. bovis (6.2%), M. bovirhinis (5.6%), M. arginini (2%), and (52.1%) of cows were co-infected with two or more Mycoplasma and Acholeplasma species. Mycoplasma co-infection significantly increased somatic cell counts (SCC) similar to conventional mastitis pathogens and compared to non-infected cows with 389.3, 550.3 and 67.3 respectively; and decreased the milk yield with 29.0, 29.9 and 34.4 l, respectively. Mycoplasma co-infection caused significant increase in protein percentage, and significant decrease in fat percentage and total milk solids, similar to other conventional mastitis pathogens. In contrast, changes in milk composition and yield caused by various individual Mycoplasma species were non-significant. CONCLUSIONS: Mycoplasma mastitis had on-farm economic consequences similar to common conventional mastitis pathogens. Results of our study indicate that co-infection Mycoplasma mastitis caused similar effect on milk composition to other mastitis pathogens and we hope these findings raise the awareness of the importance of their detection on routine diagnostic panels.

Evaluation of microbiological, cellular and risk factors associated with subclinical mastitis in female buffaloes.

OBJECTIVE: This study aimed to evaluate the microbiological and cellular milk profile for the diagnosis of subclinical mastitis in female buffaloes and to assess risk factors for predisposition of the disease. METHODS: Analyses were carried out by standard plate count (SPC), identification of species and antibiotic resistance, somatic cell count (SCC), electrical electrical conductivity of milk (ECM), and lactoferrin content in milk. Teat cups were swabbed to evaluate risk factors, observing hyperkeratosis, milking vacuum pressure and cleanliness of the site. Hence, 30 female buffaloes were randomly selected (15 from a group in early lactation and 15 in late lactation). RESULTS: The most common bacteria in the microbiological examination were Staphylococcus spp., Streptococcus spp. and Corynebacterium sp. In the antibiotic sensitivity test, 10 (58.82%) of the 17 antibiotics tested were sensitive to all isolates, and resistant bacteria were Streptococcus uberis, Streptococcus dysgalactiae, Streptococcus haemolyticus, and Escherichia coli. It was observed that positive samples in the microbiological examination showed total bacterial count between 9.10×103 to 6.94×106 colony forming units/mL, SCC between 42,000 to 4,320,000 cells/mL and ECM ranging from 1.85 to 7.40 mS/cm. It was also found that the teat cups had high microbial counts indicating poor hygiene, and even faults in the cleanliness of the animals' waiting room were observed. It is concluded that values of SCC above 537,000 cells/mL and ECM above 3.0 mS/mL are indications of mammary gland infection for this herd; however, the association of these values with a microbiological analysis is necessary to more accurately evaluate the health status of mammary glands with subclinical mastitis. CONCLUSION: Through phenotypic characterization of bacteria involved in the samples, the genera Staphylococcus spp., Streptococcus spp., and Corynebacterimum bovis were the most prevalent in this study. Faults in environment and equipment hygienization are factors that are directly associated with mastitis.