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Simple Summary: Subclinical mastitis is a common and economically significant disease that affects dairy sheep production. This study aims to develop and evaluate an advanced algorithmic approach that integrates thermal imaging, statistical texture analysis, and t-distributed stochastic neighbor embedding (t-SNE) to accurately detect subclinical mastitis in dairy sheep. This approach focuses on improving the accuracy and reliability of non-invasive subclinical mastitis detection by using more sophisticated algorithmic procedures than traditional temperature differential methods, thereby enhancing livestock management and animal health monitoring. Subclinical mastitis is a common and economically significant disease that affects dairy sheep production. Thermal imaging presents a promising avenue for non-invasive detection, but existing methodologies often rely on simplistic temperature differentials, potentially leading to inaccurate assessments. This study proposes an advanced algorithmic approach integrating thermal imaging processing with statistical texture analysis and t-distributed stochastic neighbor embedding (t-SNE). Our method achieves a high classification accuracy of 84% using the support vector machines (SVM) algorithm. Furthermore, we introduce another commonly employed evaluation metric, correlating thermal images with commercial California mastitis test (CMT) results after establishing threshold conditions on statistical features, yielding a sensitivity (the true positive rate) of 80% and a specificity (the true negative rate) of 92.5%. The evaluation metrics underscore the efficacy of our approach in detecting subclinical mastitis in dairy sheep, offering a robust tool for improved management practices. [ABSTRACT FROM AUTHOR]

Total 492 quarter milk samples from 123 animals were screened for sub clinical mastitis (SCM) by California mastitis test (CMT) and recorded animal-wise, quarter-wise incidence as 63.41 and 25.61 percent, respectively. Age-wise incidence was highest in animals aged between 5-7 years followed by animals 3-5 years, < 3 years and least in the animals aged more than 7 years. Further, the highest incidence of SCM was recorded in crossbred cows compared to native breeds. Animal wise incidence in relation to lactation number showed highest during the fourth lactation followed by fifth, second and third lactation and least in the first lactation and quarter wise incidence in relation to lactation number showed highest during the fifth lactation followed by forth, second and third lactation and least in the first lactation. Similarly, the animal-wise incidence of SCM has increased according to the stage of lactation as early, mid and late lactations. The incidence of SCM was highest in left-hind quarters followed by right-fore quarters and least in both left-fore and right-hind quarters by taking a single quarter into consideration. The highest and equal proportion of incidence was recorded both in left quarters and fore-quarters and whereas, lowest with an equal proportion of incidents reported in both right quarters and hind quarters. Quarter-wise distribution of SCM was decreased as numbers of quarters considered were increased with regard to a single quarter, two quarters, three quarters and all four quarters incidence. [ABSTRACT FROM AUTHOR]

Background: Thymus vulgaris extracts can play a significant role as alternatives for antimicrobial agents against bovine staphylococcus mastitis. Aim: This research's goal was to evaluate the antibacterial properties of an extract from T. vulgaris as an alternative to antibiotics for bovine Staphylococcus mastitis. In addition, it is important to know the effect of the extraction methods (hot alcoholic, cold alcoholic, and hot water extract) on their effectiveness. Methods: Two hundred ten cow milk samples from different areas of Basrah province had been suffering subclinical mastitis reported by using the California mastitis test (CMT). Staphylococcus species were identified by conventional microbiological technique, GP24 Kit, and nuc gene. Antimicrobial activity of various concentrations of T. vulgaris extracted (75, 50, 25) mg/ml with different methods of extraction (hot alcoholic, cold alcoholic, and hot water extract). Results: Out of 210 samples, 99 (47.1%) were positive for the CMT, and the identification rate of Staphylococci spp. by conventional microbiological technique and GP24 kit was 78 (78.8%). Out of 78 isolates of Staphylococcus spp. 48 (61.5%) were identified as Staphylococcus aureus, by using both molecular techniques using PCR and miniaturized Kit GP24 and employing the miniature GP24, the remaining 30 (38.5%) were determined to be different species of Staphylococcus. Antibacterial activity of various concentrations of T. vulgaris extracted (75, 50, 25) mg/ml with different methods of extraction revealed that hot alcoholic extract (100%) was more effective than cold alcoholic extract (66.7%), whereas there is no effect on the bacteria species with the hot water extract. Conclusion: Thymus vulgaris extracts can play a significant role as alternatives for antimicrobial agents against bovine staphylococcus mastitis. [ABSTRACT FROM AUTHOR]

The ultrasound appearance of the udder from buffalo with subclinical mastitis consisted of hypoechoic parenchyma with anechoic gland cistern, alveoli, and lactiferous duct. In the normal mammary gland of buffalo, the udder revealed hyperechoic parenchyma with interspersed anechoic alveoli and lactiferous ducts. Teat of buffalo with subclinical mastitis revealed homogenous hypoechoic features of the three-discrete layer of the parenchyma. The teat in animals without subclinical mastitis showed hyperechoic to hypoechoic features of the teat wall. The mean ± SD echo mean values of the mammary gland and teat with subclinical mastitis were relatively higher than the echo mean values in the mammary gland and teat without subclinical mastitis. Pearson's correlation showed a positive correlation between ultrasound echo mean values of the udder and CMT finding and ultrasound echo mean values of the udder and porta SCC. Also, the study showed a positive correlation between the ultrasound echo mean values of the teat and CMT findings and between the ultrasound echo mean values of the teat and SCC results. The results of the study suggest that ultrasonography can be useful in detecting subclinical mastitis in dairy Murrah buffaloes. [ABSTRACT FROM AUTHOR]

The objective of this study was to determine the activities of lactate dehydrogenase (LDH), alkaline phosphatase (ALP), gamma-glutamyl transferase (GGT), aspartate aminotransferase (AST) and alanine aminotransferase (ALT) in the milk and blood of lactating Holstein cows and investigate their association with subclinical mastitis (SCM). This study also aims to evaluate the impact of SCM and its severity based on California mastitis test (CMT) scores on the above mentioned enzymes, as well as to test the efficiency of their use as an early predictive diagnostic tool. Thirty multiparous, lactating dairy Holstein cows were examined using CMT and according to the obtained results classified into four groups; control group 1 (SCM-free = 10, score = 0), group 2 (weak positive = 8, score +1), group 3 (positive = 7, score +2) and group 4 (strong positive = 5, score +3). The milk LDH, ALP, and GGT activities were significantly higher in groups 3 and 4 compared to group 2 and the control group. LDH activity was significantly higher in group 2 compared to the control group. The mean blood LDH and ALP activities in SCM groups were significantly higher than in the control group. ALP blood activity was significantly higher in group 4 compared to group 2. The blood GGT activity was significantly higher in group 4 compared to other groups. There was a significant positive association between milk LDH, ALP, and GGT enzymes as well as the blood enzymes (ALP and GGT) in SCM cows. The results showed that subclinical mastitis causes considerable changes in the activities of enzymes in milk and blood of infected cows. [ABSTRACT FROM AUTHOR]

The present study was undertaken to evaluate prevalence of subclinical mastitis on the basis of commonly used mastitis diagnostic tests. A total of 592 functional quarters of 150 apparently healthy lactating cows were screened by modified California mastitis test, somatic cell count, electrical conductivity and milk pH. The animal-wise highest prevalence of SCM was found in somatic cell count (47.33%) followed by electrical conductivity (46%), modified California mastitis test (44.66%) and milk pH (42.67%). The quarter wise highest prevalence of SCM was recorded in somatic cell count (23.98%) followed by electrical conductivity (23.47%), modified California mastitis test (22.80%) and milk pH (21.45%). Right side quarters were found more affected then the left side quarters. Hind quarters were more affected than the fore quarters. Parity wise highest prevalence of SCM in each mastitis detection tests was observed in Vth parity. Whereas, lactation stage wise highest prevalence of subclinical mastitis was found in early lactation stage followed by mid lactation and least in late lactation stage. [ABSTRACT FROM AUTHOR]

Background and Aim: Mastitis in dairy cattle is associated with a high rate of morbidity and death, which has major implications for milk production and quality. This study aimed to investigate the protein component and the activity of matrix metalloproteinase-2 (MMP-2) and -9 (MMP-9) in raw milk samples with different testing scores determined using the California mastitis test (CMT). Materials and Methods: Thirty cows were employed in the study, and milk from each quarter was tested for subclinical mastitis (SCM). According to the results of CMT, raw milk samples were classified into five categories: Healthy (score 0), trace (score T), weakly positive (score 1), distinctly positive (score 2), and strongly positive (score 3) for somatic cell count (SCC). The total milk protein was analyzed using the Bio-Rad protein assay, and the milk protein composition was determined using the sodium dodecyl sulfate-polyacrylamide gel electrophoresis technique. In addition, gelatin zymography was used to evaluate changes in proteolytic abilities. Results: Milk samples with CMT scores of 1 and 3 had the highest total milk protein levels (32.25 ± 12.60 g/L and 32.50 ± 7.67 g/L, respectively), while the samples from healthy cows (CMT score 0) were only 6.75 ± 1.64 g/L. Globulin and lactoferrin were significantly increased in samples with a CMT score of 3 compared with those with other CMT scores. The bovine serum albumin level in samples with a CMT score of 2 was significantly (p < 0.05) higher than those with other CMT scores. No significant differences in casein abundance were found among samples with different CMT scores. Results from analysis of proteolytic activities demonstrated that the level of MMP-9 in samples with a CMT score of 3 was significantly (p < 0.05) higher than those with other CMT scores. Conclusion: The protein content and gelatinolytic activity of milk were drastically altered by the number of SCC, mainly due to SCM. [ABSTRACT FROM AUTHOR]

Subclinical mastitis (SCM) is a major health problem of dairy animals in India and across the globe. An identification of potential risk factors of SCM can help for efficient udder health management in dairy animals. In this study, apparently healthy cows (HF crossbred: n = 45; Deoni: n = 43) were screened for SCM during different seasons through milk somatic cell count (SCC: reference test using 200 × 103 cells/ml as cut off value), California mastitis test (CMT) and differential electrical conductivity (DEC) test at an organized research farm. SCM positive milk samples (n = 34) were inoculated in selective media for Coliform sp., Streptococcus sp. and Staphylococcus sp. and DNA was isolated (n = 10) for species confirmation by 16s rRNA method. Both bivariate and multivariate models were used for risk assessment. We found the cumulative prevalence of 31 and 65% SCM in Deoni and crossbred cows, respectively. Screening of 328 crossbred cows under field conditions revealed point prevalence of 55% SCM. Multivariate analysis revealed stage of lactation (SOL), milk yield in previous lactation and test day milk yield in Deoni cows, as well as parity and mastitis treatment history in current lactation in HF crossbred cows as risk factors. SOL was a significant factor under field conditions. Receiver operated characteristic curve analysis revealed better accuracy of CMT than DEC. We found more mixed infections due to Staphylococcus sp. and Streptococcus sp. in culture, while 16s rRNA based molecular method revealed lesser-known pathogens associated with SCM. It is concluded that SCM prevalence rate is higher in crossbred than indigenous cows and these breeds have different risk factors for SCM. HF crossbred cows had similar SCM prevalence rate under different farming conditions, where CMT can be used for SCM diagnosis with excellent accuracy. The 16s rRNA method is useful for specific identification of lesser known and emerging mastitis pathogens. [ABSTRACT FROM AUTHOR]

The present study was designed to determine the quarter-wise prevalence of sub-clinical mastitis in cattle on the basis of various indirect mastitis detection tests. For this purpose, nine hundred eighty (980) quarter milk samples from 247 cows were screened by various mastitis detection tests viz Milk pH test, modified California mastitis test (MCMT), somatic cell count (SCC) and electrical conductivity (EC). The overall quarter wise highest prevalence of SCM was found in somatic cell count (24.49%) followed by electrical conductivity (23.47%), modified California mastitis test (22.45%) and milk pH (21.94%). Right side hind quarters were more affected than the left side fore quarters in each mastitis detection tests. [ABSTRACT FROM AUTHOR]

The study describes the identification of the etiological agents of subclinical mastitis (SCM) among lactating dairy cows under different phases of lactation in an organised dairy farm of Thrissur district, Kerala. The preliminary diagnosis of subclinical mastitis (SCM) was made using California Mastitis test (CMT), a cow side field test. The somatic cell count (SCC) was estimated and the milk samples of affected quarters were subjected to bacterial isolation and identification. The predominant causative agents isolated from milk of cows with SCM were coagulase negative staphylococci (56.25 per cent) followed by S. aureus (25 per cent) and Micrococci spp. (18.75 per cent). Further species identification of the coagulase negative staphylococci revealed that the majority were S. xylosus (28.23 per cent) followed by S. scuiri (15.63 per cent), S. hominis (9.38 per cent) and S. schleiferi (3.13 per cent). [ABSTRACT FROM AUTHOR]

Subclinical mastitis is an insidious disease of the mammary gland that negatively impacts the production of dairy cows. The objective of the present study is to screen subclinical mastitis in dairy cattle farms. A total of 208 lactating cows from five herds were examined and screened by the California mastitis test (CMT). Bacteriological analysis was performed on all CMF positive milk samples to characterize the presence of infection due to the genus Staphylococcus; as well as studying of the sensitivity of these isolated strains to antibiotics. The results showed that out of 208 cows screened by CMT, 71.15% were positive. Bacteriological analysis revealed that 111 samples found to be of the genus Staphylococcus, (75%). The characterization of the strains affirmed that the coagulase positive staphylococci represent 51.34% with a predominance of Staphylococcus aureus with a rate of 40.54% and the coagulase negative staphylococci represent 48.61%. The results of the antibiotic resistance revealed that the strains of coagulase positive Staphylococci particularly S aureus are resistant to the combination of amoxicillin and clavulanic acid, oxacillin and tetracycline with levels ranging from 4.4%, 44, 4% and 11.1% respectively. While coagulase negative Staphylococci showed resistance to the same molecules with 9.2%, 16.6% and 31.3% respectively. The obtained results demonstrated a very strong correlation between CMT and bacteriological findings. CMT seems to be an advantageous tool to expand, for systematic and regular screening against subclinical mastitis. [ABSTRACT FROM AUTHOR]

Intramammary antibiotic (AB) and internal teat sealants (TS) infusion at dry-off have been used to prevent intramammary infections (IMI) in dairy cows during the dry period and reduce the risk of mastitis during the dry period and subsequent lactation. A randomized clinal trial was completed on eight California dairy herds to estimate the effects of different dry cow therapies (AB, TS, AB + TS or None) on clinical mastitis and culling. A total of 1273 cows were randomized to one of the four treatment groups over summer and winter seasons. For each enrolled cow, microbiological testing was done on quarter milk samples collected from the first detection of clinical mastitis within the first 150 days in milk (DIM) in the subsequent lactation. Statistical analysis was done using generalized linear mixed models. There were no significant differences in the odds of clinical mastitis or culling between cows treated with AB, TS, or AB + TS compared to the controls. Dry cow therapy with AB and/or TS had no statistically significant effect on clinical mastitis and cow culling during the first 150 DIM. [ABSTRACT FROM AUTHOR]

Subclinical mastitis is subtle and more difficult to detect. Subclinical mastitis usually remains unnoticed because the milk and udder appear normal. Therefore, knowledge of regular physical examination of the udder and diagnostic screening tests for early detection of mastitis and proper treatment of the affected animals is one of the paramount importance to minimize losses encountered due to subclinical as well as clinical mastitis. The present study was conducted to evaluate the prevalence of subclinical mastitis in apparently healthy cattle in and around the Udaipur District of Rajasthan. A total of 769 milk samples from functional quarters of 200 apparently healthy lactating cows collected in and around Udaipur city were screened for subclinical mastitis by California mastitis test and somatic cell count test. The overall animal-wise prevalence based on CMT was 68.5% (137/200) and quarter-wise prevalence was 31.73% (244/769) in cattle. Animal-wise prevalence based on somatic cell count (>500,000/ml) of milk was recorded in 47.50% (95/200), whereas 20.02% (154/769) of the quarters were positive in cattle. [ABSTRACT FROM AUTHOR]

The present study was undertaken to investigate the effect of subclinical mastitis on some indicators of inflammation in milk, and their correlation with somatic cell count (SCC) in cattle. A total of 20 lactating cows positive for subclinical mastitis and equal number of cows negative for subclinical mastitis by both modified California mastitis test (MCMT) and somatic cell count (SCC) were examined for the levels of fibrinogen, orotic acid and some of milk enzymes. Cows having subclinical mastitis were found to have significantly higher levels of alkaline phosphatase (ALP), lactate dehydrogenase (LDH) and aspartate amino transferase (AST) activity in the milk in comparison to the control cows. Fibrinogen and orotic acid levels in subclinical mastitis (SCM) milk were also significantly higher than that of healthy cows. Milk somatic cell count (SCC) showed highest correlation with ALP (r = 0.83, P < 0.01) followed by LDH (r = 0.71, P < 0.01) and AST (r = 0.70, P < 0.01). Fibrinogen, an acute phase protein (r = 0.79, P < 0.01) and orotic acid (r = 0.88, P < 0.01), an intermediate metabolite also had significant positive correlation with SCC. Thus, among all 5 indirect indicators of inflammation, ALP could be considered as most economical and sensitive marker of subclinical mastitis. Therefore, it could be used for early detection and control of SCM in dairy herds. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the prevalence and risk factors of subclinical mastitis (SCM) in lactating cows in northwest China. A total of 1,590 lactating cows from 38 different-scale dairy farms located in Gansu province and Ningxia Hui autonomous region were selected for this study. SCM was confirmed by California Mastitis Test. Cow-level risk factors including age, parity, lactation stage, milk yield, clinical mastitis history, teat damage, hygienic-sanitary quality, milking method and season were identified through univariate analysis and multivariate analysis using SPSS 19.0. In the two regions, the prevalence of SCM was 25.92% at cow level and 16.40% at quarter level. On large-, medium- and small-scale dairy farms, the SCM incidence was 21.46%, 26.74% and 33.16%, respectively. Among the potential risk factors, parity, lactation stage, clinical mastitis history and teat damage significantly influenced the occurrence of SCM (P<0.01) at cow level. This study indicated high-level prevalence of SCM and identified four risk factors for SCM which can be addressed by practical management of dairy cows for the local farms. [ABSTRACT FROM AUTHOR]

This study aimed to detect the incidence of subclinical mastitis (SCM) in the milk of dairy cows in Sohag city, Egypt. 100 quarter milk samples from all quarters of 25 dairy cows with apparently healthy udders were examined by strip cup test, California mastitis test (CMT), White side test (WST), chemical and bacteriological tests. From the obtained results, it was found that none of the strip cup test was positive, while CMT revealed 53% positive with various degrees, and the WST revealed 49% positive with various degrees. According the estimation of chloride % and lactose %, the Koestler number was revealed 33% mastitic, 25% suspected and calculated 42% normal samples. According the bacteriological examination, out of the 39 bacterial isolates from the examined milk samples, Staph. aureus, Strept. agalactiae and E. coli were estimated 64.10%, 28.21% and 7.69%, respectively. [ABSTRACT FROM AUTHOR]

A total of 100 halves milk samples from 50 apparently healthy goats were collected and subjected to culture examination, somatic cell count (SCC), California mastitis test (CMT), and electrical conductivity (EC) to find out the prevalence of sub-clinical mastitis, to determine the bacterial isolates associated with sub-clinical mastitis in goats. The Prevalence of sub-clinical mastitis was found to be 46 per cent on udder halves basis and 66 per cent on animal basis. Staphylococci were the most prevalent organisms (38.02%) among bacterial isolates followed by Streptococci (29.58%), Coliform organisms (16.90%), Bacillus spp. (8.45%) and Corynebacterium spp. (7.04%). Mean values of somatic cell count and electrical conductivity of culturally positive halves were significantly higher than the mean values of culturally negative halves. [ABSTRACT FROM AUTHOR]

Objectives of this study is to evaluate possibilities for early detection of udder's diseases of Lithuanian Black and White cows and compare thermography and routine California mastitis test (CMT) results. Cows were examined in the negative and at positive ambient temperature. Infrared thermography (IRT) applied skin surface thermograms of teats in the area of Furstenberg's rosette analyzed as posing evidence based signs of subclinical mastitis coincide with the CMT. It is shown, that subclinical inflammatory processes of cow's mammary gland can be simply and successfully identified at an early stage of pathology development applying the thermal imaging method. IRT results measuring the skin surface temperature of teat sphincters of healthy dairy cows and cows with subclinical mastitis were completely similar to the CMT findings. Effectiveness of IRT does not depend from ambient conditions: inflammation can be easily detected both in positive and negative ambient temperatures. We confirm IRT being as alternative, noninvasive, high sensitive, rapid and portable method for subclinical various origins inflammatory processes of cow's udder, which can be certified for practical subclinical mastitis screening and subsequent detection. [ABSTRACT FROM AUTHOR]

This study was undertaken to investigate the effectiveness of California mastitis test (CMT), white side test (WST), chlorine test and electrical conductivity (EC) in the diagnosis of subclinical mastitis in dairy cows in a comparison to somatic cell count (SCC) as a standard method for detection of subclinical mastitis. One hundred random samples of cow's milk were collected from different dairy farms at Dakahlia Governorate, Egypt. SCC revealed that 27% of samples contained less than 2 x 105 SCC/ml. and were considered negative for presence of subclinical mastitis, while mastitic samples (73%) contained higher numbers of SCC exceeded 2 x 105/ml. CMT results revealed that 27.0% of the examined cow's milk samples were negative and 73.0% were among the positive samples. The mean values of chlorine % of normal and mastitic cow's milk samples were 0.093 and 0.157, respectively. EC of normal and mastitic cow's milk samples revealed that the mean values were 4.08 and 7.42 mS/cm, respectively. Results showed significant correlation of these parameters in detection of subclinical mastitis milk samples. [ABSTRACT FROM AUTHOR]

Abstract: The prevalence of subclinical mastitis and associated risk factors at the herd, cow and quarter level were studied using multilevel modelling in smallholder dairy farms in Jimma, Ethiopia. Forty-two herds, out of the 55 dairy farms located in Jimma (76%), were visited, a questionnaire was performed, and 635 quarters belonging to 176 lactating cows were screened to detect the presence of subclinical mastitis using the California Mastitis Test (CMT). Sixty-two percent of the cows and 51% of the quarters were subclinically infected. Quarters from cows in later stage of lactation (>180DIM) [opposed to early lactation (<90DIM)] were more likely to be subclinically infected (OR=2.40, 95% CI=1.44–3.99). Overall, quarters from cows milked by squeezing (as opposed to stripping) were less likely to be subclinically infected (OR=0.45, 95% CI=0.29–0.71), although quarters from cows with tick-infested udders were more likely to be subclinically infected when milked by squeezing (as opposed to stripping). The milking technique did not influence the likelihood of infection in cows without ticks on the udder. This study stresses the high prevalence of subclinical mastitis in smallholder dairy farms in Jimma and a lack of awareness of the existence of the disease among dairy farmers. Implementation of a mastitis prevention program adapted to the local needs, including a focus on milking technique, application of appropriate tick control measurements as well as fertility management, allowing cows to be dried-off at a more appropriate moment, are needed. To conclude, milking by squeezing instead of stripping, but not of cows with tick-infested udders, as well as fertility management could reduce the subclinical mastitis prevalence (and incidence) on the short term. [Copyright &y& Elsevier]

This study was conducted to determine the effectiveness of the electrical conductivity (EC) method on the diagnosis of subclinical mastitis in dairy cows comparing with somatic cell count (SCC) and California mastitis test (CMT), and also to investigate the eff ect of these values on the amount of total viable bacteria, density, freezing point, and mineral substances. A total of 386 milk samples collected from quarters of 188 cows at 10 diff erent farms were used as materials. Of the samples, 258 (66.85%) were CMT (+), 85 (22.02%) were CMT (++), and 43 (11.13%) were CMT (+++). The mean EC and SCC were 25.71, 28.02, and 29.63 mS and 249,453, 1,167,058, and 2,108,139, respectively, according to the CMT results. Th e total viable bacteria counts ranged from 3.4771 to 6.9395, from 3.4771 to 7.3617, and from 4.7782 to 7.5315 log CFU/mL, respectively. Th e average amounts of mineral substances were 0.65%, 0.70%, and 0.76%; the density values were 1.031, 1.0297, and 1.029; and the freezing points were -0.5281, -0.5285, and -0.5282, respectively. As a result, it has been concluded that EC showed similarity with the CMT and the SCC in the detection of subclinical mastitis; furthermore, its reliability would further increase when used together with the other diagnostic methods. [ABSTRACT FROM AUTHOR]

Simple Summary: Subclinical mastitis represents a significant disease in dairy animals and negatively impacts udder health. Genetics, pathogens, and poor health and management procedures in dairy animals contribute primarily to this disease. Animal genetics plays a major role in disease resistance and susceptibility. Studying single-nucleotide polymorphisms in genes helps to detect resistant and susceptible animals. Transferrin is one of the important glycoproteins involved in the innate immune system that prevents iron availability to pathogens. Several studies have reported polymorphism in the transferrin gene in dairy animals with mastitis, but no detailed information on in silico tools is available for identification and verification. So, this study was carried out to detect polymorphism in the transferrin gene in healthy and mastitic cows, and to use various in silico based tools and software to find the impact of single-nucleotide polymorphisms (SNPs) on animal health. The results indicated three SNPs were located in the transferrin gene of Holstein Friesian cross-bred dairy cows. Moreover, the use of online computational tools provided significant knowledge regarding whether the SNPs would be deleterious, damaging, benign, neutral, or affect protein stability and function. Dairy cattle with a high milk yield are susceptible to many infectious diseases, such as mastitis. Subclinical mastitis (SCM) is the most prevalent form of mastitis that predominantly affects animal health, and causes adverse effects on the quality and quantity of milk. In dairy animals, subclinical mastitis often remains undetected, as no gross changes in udder characteristics are visible. In the present study, 135 Holstein Friesian dairy animals were selected and screened as healthy (n = 25) and mastitic (n = 110) based on diagnostic tests such as the California mastitis test, pH, electrical conductivity, and somatic cell count. In this study, the somatic cell count was used as a gold-standard test in differentiating subclinical mastitis animals from healthy ones. The present study was carried out to study polymorphisms in the bovine transferrin gene in cows (with subclinical mastitis and healthy). For the early detection of resistant/or susceptible animals, a useful marker could be provided by the detection of single-nucleotide polymorphisms (SNPs) in the transferrin gene, which are often associated with mammary innate immune response. The sequencing results revealed three nucleotide substitutions: two transversions (230 A > C, 231 C > A) and one transition (294 A > G) in susceptible cows as compared to disease-free subjects. The nucleotide variations at position 230 (GAC > GCA) and 231 (GAC > GCA) were nonsynonymous, and corresponded to an amino acid change from aspartic acid to alanine; whereas at position 294 (GAA > GAG), the mutation was synonymous. In the present study, many in silico tools were taken into consideration to determine the effect of SNPs on protein structure and function. The PROVEAN tool found the amino acid substitution to be neutral and deleterious. PolyPhen-2 revealed the amino acid variations at positions 320 and 321 to most likely be damaging; and at the 341 position, the variations were benign. The I-Mutant and MUpro tools found that the protein stability decreased for nonsynonymous variations. The SIFT tool revealed the protein function was likely to be affected in nonsynonymous variations, with no change in the case of synonymous ones. Phylogenetic analysis of the bovine transferrin gene revealed a close relation of the CA allele with the Bos taurus transferrin, while the G allele was closely related to a cross of Bos indicus × Bos taurus serotransferrins, followed by the Bison bison transferrin. The least relation was shown by both alleles to Capra hircus, Ovis aries, and Bubalus bubalis. [ABSTRACT FROM AUTHOR]

The objective of the study was to evaluate the effect of individual quarter dry-off in management of subclinical mastitis on clinical development, behavior during milking, and short-term production loss. The study was conducted as a controlled randomized trial in 5 commercial organic dairy herds. Seventy cows meeting the inclusion criteria were randomly allocated to 1 of 2 treatments: individual quarter dry-off (QDO) or continued milking. The inclusion criteria constituted an increase in somatic cell count from below to above 400,000 cells/mL at milk recording and identification of a quarter scoring of at least 3 and higher than the remaining quarters at California mastitis testing (scale 1-5). Quarters were evaluated clinically for atrophy, swelling, firmness, signs of pain, and milk leakage, and rectal temperature of the cows was measured. Behavior during milking was assessed as average frequency of hind limb tripping and kicking during milking obtained by registrations on video recordings. Milk production loss was estimated based on average daily milk yield for 19 d subsequent to treatment start, with reference to average daily milk yield in 19 d before treatment. The QDO treatment was associated with quarter swelling and increased quarter firmness around d 10 from treatment start and with quarter atrophy around d 40 from treatment start. However, around d 40 from treatment start 35% of the dried-off quarters remained nonatrophic and only 6% of the quarters were completely dry. The QDO was associated with signs of pain related to the dried-off quarter. No obvious effects on behavior during milking of QDO treatment was observed. On average the production loss associated with QDO was 4.1 kg/d (95% confidence interval: 3.1-5.0) greater than for continued milking. The production loss depended on parity, days in milk, and prior yield on the quarter subjected to dry-off (Q1). The production loss increased with increasing prior yield on Q1. For the majority of cows the increase in production loss was below 1 kg of milk/d when the prior yield on Q1 increased by 1 kg of milk/d, demonstrating a compensatory production potential of the nontreated quarters. Early lactation multiparous cows showed the greatest compensatory potential. Further studies into the effect on welfare, cure rates, and transmission are needed to determine the feasibility of individual quarter dry-off., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)

The objectives of this study were to estimate the accuracy of Somaticell (Idexx Laboratories Inc., Westbrook, ME), California Mastitis Test (CMT), and microbiological examination of composite milk (MEC) to diagnose Streptococcus agalactiae intramammary infections (IMI), and to assess the agreement between Somaticell and CMT to detect these infections. A secondary objective was to estimate quarter- and cow-level prevalence of S. agalactiae IMI in the herds included in the study. Seven farms were included in the study. The CMT was performed and aseptic milk samples were collected from all quarters of all lactating cows. Composite milk samples were produced in the laboratory by mixing milk from all quarters of each sampled cow. The Somaticell test was performed on a subset of S. agalactiae-positive (n = 167) and S. agalactiae-negative (n = 152) quarter milk samples. Microbiological examination of quarter milk samples (MEQ) was considered the reference test for diagnosing S. agalactiae IMI. The accuracy of all tests at various thresholds was estimated using Bayesian latent class models. Apparent prevalence of S. agalactiae IMI was 15.8% (n = 184/1,164) at the quarter level (based on MEQ) and 28.5% (n = 83/291) at the cow level (based on MEC). True prevalence, as determined by Bayesian models, was 13.0% [95% credible interval (CR): 6.4-24.4%] at the quarter level, and 25.6% (95% CR: 15.3-39.5%) at the cow level. At the cow level (n = 285), sensitivity and specificity of MEC were 95.6 and 99.5%, respectively. The accuracy of Somaticell (n = 319 quarters) to identify S. agalactiae-infected quarters was 75.4, 86.4, 88.9, 89.4, and 91.0% at thresholds of 98,000, 147,000, 205,000, 244,000, and 282,000 cells/mL, respectively. The accuracy of CMT was 87.6, 90.7, 90.8, and 87.4% at thresholds of trace, 1, 2, and 3, respectively. The areas under the receiver operating characteristic curve for Somaticell and CMT were 94.5% (95% confidence interval: 91.8-97.2%) and 92.0% (88.6-95.4%), respectively. At the tested thresholds, the sensitivity of Somaticell ranged from 94.9 to 99.5% to detect S. agalactiae IMI, and specificity ranged from 48.1 to 87.1%. The sensitivity of Somaticell at the lowest threshold (69,000 cells/mL; sensitivity = 99.9%; 95% CR: 98.2-100%) was higher than that of CMT at any tested threshold. Results of this study could be used at the farm level to reduce the use of antimicrobials and reach specific goals in S. agalactiae eradication programs., (Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.)