High Milk Somatic Cell Count Research Articles

Management practices and milk quality in dairy goat farms in Northern Italy

A large-scale survey was conducted on 173 dairy goat farms in Northern Italy to provide an updated view on farm management practices and to investigate relations among management factors, herd traits and milk yield and quality with particular focus on milk somatic cell count (SCC) and milk fat/protein reversion syndrome. Monthly individual milk analyses (fat, protein and lactose percentages, SCC) and bulk tank milk analyses (fat, protein and lactose percentages, standard plate count (SPC), urea and casein) from 91 farms out of the 173 farms were collected for a year. Farming systems showed wide variability and were characterised by the coexistence of intensive farms adopting advanced technologies and extensive traditional ones. Average milk production was 1.25 kg/milking with high variability, significantly influenced by days in milk, month of kidding, herd size and parity. Out-of-season breeding was predicted to cause a slight reduction of milk production. The reversion syndrome between milk fat and protein contents affected more than half of samples. It worsened after 100 d of lactation and occurred earlier during lactation when kidding was in the late season (April–June) compared to kidding in the first months of the year. The defect was associated with high SCC in milk. The yearly average milk SCC was 5.8 log10 cells/mL; it was higher at the end of lactation and in goats kidding in the late season. A negative relationship between SCC and milk yield was found with an estimated loss of 0.23 kg per milking for each additional point of log10 SCC.

Effect of somatic cell count on milk composition and mozzarella cheese quality

The aim of this study was to investigate the effect of somatic cell count (SCC) on mozzarella cheese quality. Three categories of raw milk were selected: low (SCC <115 000 cells/ml), medium (SCC=422 000 cells/ml), and high (SCC>987 000 cells/ml). Cheeses were produced on the same day of milk collection and were vacuum packed in plastic bags and analysed weekly for 60 days at cold storage (4 °C). As somatic cell count increases, casein content, casein as a percentage of true protein, lactose content, and titratable acidity decrease significantly in raw milk. No significant differences were observed in moisture, fat, and total protein contents among mozzarella cheese samples from the different SCC categories. However, cheese samples produced from high SCC milk had significantly higher pH (6.83) compared to samples produced with low and medium SCC milk, 5.58 and 5.46, respectively. The extension of proteolysis was not significant for cheese samples made from raw milk with low SCC during the first 30 days of cold storage. Proteolysis levels increased significantly on the 15th storage day for cheeses made with medium and high SCC, whereas significant increases were only observed on the 45th storage day for cheeses made with low SCC.

Short communication: Association between udder health status and blood serum proteins in dairy cows

The aim of this study was to investigate the association between udder health (UH) status and blood serum proteins (i.e., total protein, albumin, globulin, and albumin-to-globulin ratio) in dairy cows. Blood and milk samples were collected from 1,508 cows of 6 different breeds (Holstein Friesian, Brown Swiss, Jersey, Simmental, Rendena, and Alpine Grey) that were housed in 41 multibreed herds. Bacteriological analysis was performed on milk samples with somatic cell count (SCC) >100,000 cells/mL and bacteria identification was confirmed by multiplex-PCR assays. Milk samples were grouped into 7 clusters of UH status: healthy (cows with milk SCC <100,000 cells/mL and not cultured); culture-negative samples with low, medium, or high SCC; and culture-positive samples with contagious, environmental, and opportunistic intramammary infections. Data of blood serum proteins were analyzed using a linear mixed model that included the fixed effects of stage of lactation, parity, breed, herd productivity (high or low production) and UH status, and the random effect of herd-date within herd productivity. Culture-negative samples with high milk SCC, which were most likely undergoing a strong inflammatory response and whose pathogens could not be isolated because they were engulfed by macrophages or because they had already cleared, and milk samples infected by contagious and environmental bacteria were associated with greater globulin concentrations (and lower albumin-to-globulin ratio) in blood. Variation in blood serum proteins seems to be associated with inflammatory status rather than infection, as serum globulin significantly increased in UH status groups with the highest milk SCC and no differences were observed among intramammary infections pathogens. Blood serum proteins can be a mammary gland inflammation indicator, but cannot be used to differentiate among different UH status groups.

Prevalence of subclinical mastitis in Finnish dairy cows: changes during recent decades and impact of cow and herd factors

BackgroundThe dairy industry has undergone substantial structural changes as intensive farming has developed during recent decades. Mastitis continues to be the most common production disease of dairy cows. Nationwide surveys of mastitis prevalence are useful in monitoring udder health of dairy herds and to study the impact of structural changes on the dairy industry. This survey on bovine subclinical mastitis was the first based on cow composite milk somatic cell count (SCC) data from the Finnish national health monitoring and milk recording database. A cow with composite milk SCC ≥200,000 cells/ml in at least one of the four test milkings during the year was considered to have subclinical mastitis and a cow with composite milk SCC ≥200,000 cells/ml in three or in all four test milkings during the year to have chronic subclinical mastitis. The aim of the study was to determine the prevalence of subclinical mastitis and chronic subclinical mastitis in Finland in 1991, 2001 and 2010 and to investigate cow and herd factors associated with elevated SCC.ResultsPrevalence of subclinical mastitis in Finland decreased over recent decades from 22.3% (1991) and 20.1% (2001) to 19.0% (2010). Prevalence of chronic subclinical mastitis was 20.4% in 1991, 15.5% in 2001 and 16.1% in 2010. The most significant cow and herd factors associated with subclinical mastitis or high milk SCC were increasing parity, Holstein breed, free-stalls with an automatic milking system and organic production. Milk SCC were highest from July to September. Main factors associated with chronic mastitis were increasing parity and Holstein breed.ConclusionsPrevalence of subclinical mastitis in Finland decreased over recent decades, the greatest change taking place during the first decade of the study. Prevalence of chronic subclinical mastitis significantly decreased from 1991. The most significant factors associated with both types of mastitis were increasing parity and Holstein breed, and for subclinical mastitis also free-stalls with automatic milking. National surveys on mastitis prevalence should be carried out at regular intervals to monitor udder health of dairy cows and to study the impact of the ongoing structural changes in the dairy industry to enable interventions related to udder health to be made when needed.

Lactation performance and diet digestibility of dairy cows in response to the supplementation of Bacillus subtilis spores

Bacillus subtilis is a transitory microorganism of the digestive tract, non-pathogenic to animals, and capable of forming spores that are resistant to heat and cold. As an animal feed probiotic the microorganism is supposedly capable of increasing diet digestibility and immunity. Two experiments were conducted to evaluate the effect of Bacillus subtilis spores on milk yield and composition and diet digestibility. In both experiments lactating dairy cows were fed in tie stalls and treatments were force-fed once per day. In experiment 1, 18 Holsteins in late lactation (246±75 days in milk) received a sequence of the treatments Bacillus subtilis strain C-3102 (3.0×109 colony-forming units of spores per day) or Placebo in a crossover design with 39-day periods, a 10-day wash-out between periods, and response evaluated after the 28th day of the periods. The supplementation of Bacillus subtilis spores did not elicit detectable changes in intake (18.3kg/d, P=0.91), milk (25.3kg/d, P=0.66) and solids yield and concentration, total tract nutrient digestibility, and chewing activity. In experiment 2, 30 cows (161±72 days in milk) with high milk somatic cell count (725,000 cells/mL) received the same treatments for 16 weeks, in a covariate adjusted randomized block design with repeated measures over time. Bacillus subtilis spores increased the yields of milk (25.3 vs. 23.6kg/d, P=0.02), protein (0.816 vs. 0.763kg/d, P=0.01), total solids (2.718 vs. 2.566kg/d, P=0.05), and energy (60.7 versus 56.5 MJ/d, P=0.02) and milk urea-N tended to be reduced (19.3 vs. 20.8mg/dL, P=0.06). Milk somatic cell count did not differ between treatments. The positive lactation response to Bacillus subtilis spores supplementation occurred when the probiotic was fed for 16 weeks and there was no evidence to suggest that increased diet digestibility was a mediator of the response.

Vitamin Fortification of Fluid Milk.

Vitamin concentrates with vitamins A and D are used for fortification of fluid milk. Although many of the degradation components of vitamins A and D have an important role in flavor/fragrance applications, they may also be source(s) of off-flavor(s) in vitamin fortified milk due to their heat, oxygen, and the light sensitivity. It is very important for the dairy industry to understand how vitamin concentrates can impact flavor and flavor stability of fluid milk. Currently, little research on vitamin degradation products can be found with respect to flavor contributions. In this review, the history, regulations, processing, and storage stability of vitamins in fluid milk are addressed along with some hypotheses for the role of vitamin A and D fortification on flavor and stability of fluid milk.

Compositional profile of ovine milk with a high somatic cell count: A metabolomics approach

Ovine milk (Sarda breed) with high somatic cell count (SCC) (>1 × 106 cell mL−1) was compared with similar milk of low SCC (<150 × 103 cell mL−1) using a metabolomics approach, whereby the metabolite profile of milk was studied by gas chromatography coupled to mass spectrometry. Discriminant analysis indicated that high SCC milk samples have metabolite profiles from those of low SCC samples. Malic acid, ribitol, glucose and medium-short chain fatty acids were up-regulated in milk with high SCC, while stearic acid, oleic acid, scyllo-inositol, glutamine, threonine, and glycine were down-regulated. These differences may be related to metabolite release by somatic cells, inflammation status, altered permeability of the udder tight junctions, and changes in milk osmotic equilibrium. Moreover, high SCC milk samples showed higher levels of proteins, casein and fat, lower concentrations of lactose and urea, and a different fatty acid profile from that of low SCC milk.

Alteration in the in vitro activity of milk leukocytes during different parity in high yielding cross-bred cows

In vitro activity of milk leukocytes (viz. neutrophils, lymphocytes and macrophages) was evaluated in forty-eight (48) clinically healthy high-yielding cross-bred cows of mid-lactation stage (100–200 days of lactation), divided into four groups namely 1st parity (n = 12), 2nd parity (n = 12), 3rd parity (n = 12) and 4th and above parity (n = 12). Milk samples were taken (250 ml/cow) were taken. Milk somatic cell counts (SCC) and differential leukocyte counts (DLC) were performed microscopically. In vitro phagocytic index (PI) of milk neutrophils and macrophages was evaluated by colorimetric nitro blue tetrazolium reductive assay. Mitogen-induced milk lymphocyte blastogenic response was measured by colorimetric MTT (tetrazolium) assay after isolation of the milk leukocytes by density gradient centrifugation. Milk SCC differed significantly (p < 0.01) between different parity. Cows of 4 and above parity showed significantly (p < 0.01) higher milk SCC compared to primiparous cows. There was no significant difference in milk DLC during different parities in high-yielding cross-bred cows. There was a significant (p < 0.01) variation in lymphocyte blastogenesis amongst parity. The highest value of lymphocyte blastogenesis was seen at 3rd parity, whereas lowest value was obtained in the cows of both 1st and 4th or above parity. PI of milk neutrophils did not differ significantly between parity. PI of milk macrophages was significantly (p < 0.01) higher in 3rd parity and lower (p < 0.01) in 1st and 4th parities. The study indicated that depressed activity of milk lymphocytes and macropages was lower and SCC was higher in the cows of 4th and above parity indicating more mammary stress and hence susceptible to udder infection and mastitis. Therefore, better care and managemental interventions should be taken around these periods.

Use of Microfiltration to Improve Quality and Shelf Life of Ultra-High Temperature Milk

The main objectives of this research were to evaluate the efficacy of microfiltration in extending the shelf life and improving the quality of ultra-high temperature (UHT) milk. Results showed that in high somatic cell counts (SCC) and low SCC raw milk, microfiltration resulted in an average 3.56 and 3.57 log reduction of total bacterial counts, and 1.52 × 106 and 2.10 × 105 to <1.00 × 103 of SCC, respectively. Microfiltered UHT milk had higher pH values and lower titratable acidity compared to nonmicrofiltered UHT control milk during storage. After 112 days and 63 days of storage, there were significant differences of noncasein nitrogen/total nitrogen between the microfiltered UHT milk and nonmicrofiltered UHT control milk in high SCC and low SCC milk (P < 0.05). Particle size distribution in microfiltered UHT milk followed monodisperse distribution during storage. The shelf life of microfiltered UHT milk made by low SCC and high SCC raw milk were effectively extended by 21 and 63 days. Practical Applications Microfiltration process was to reduce bacteria and to remove somatic cell counts (SCC) of raw milk. Compared with nonmicrofiltered ultra-high temperature (UHT) control milk, the quality of microfiltered UHT milk was greatly enhanced. Microfiltration in combination with UHT process resulted in longer shelf life of UHT milk, especially for high SCC milk.

Variation in Milk Yield, Contents and Incomes According to Somatic Cell Count in a Large Dairy Goat Population

Between 2009 and 2014, 758,382 monthly test-day records were obtained from 65,056 Murciano-Granadina goats in 132 Spanish dairy flocks. Variables measured were somatic cell count (SCC), milk yield and fat and protein percentages; means were 5.78log10 cells/ml, 2.04 L/day, 5.37% and 3.67%, respectively. Significant effects of year, herd test date, season, parity, month of lactation, litter size and covariables milk yield, fat and protein contents were evidenced on SCC. The regression slopes were negative for milk yield an d positive for fat and protein content, thus pointing out that high SCC in milk were associated with low milk yield and high contents. A second ANOVA was built to evaluate the evolution of test-day variables as SCC level increased within lactation. The percentages estimated in losses of milk yield for SCC levels 1 million cells/ml, 2 million cells/ml, 3 million cells/ml and >7 million cells/ml were 11.4%, 19.5%, 24.2% and 35.7%, respectively. Milk contents gains were also quantified. Milk incomes per goat and day (according to current payment system) revealed important economic losses (from 9.5% to 31.6%) for abovementioned SCC levels. Results emphasize the importance of SCC as a limiting factor for milk incomes in dairy goats.

Somatic cell count of milk from different goat breeds

Abstract There is no standard limit value for somatic cell count (SCC) of raw goat milk in the EU despite that excellent hygienic quality milk is needed for the manufacture of fermented milk products or cheese varieties. Mastitis often results such high SCC - besides the potential risk for humans - that the clotting of milk will not be perfect, resulting slack curd with higher whey releasing; furthermore, wrong structure, ripening, bad sensory properties of cheese can also be its consequences. In this paper, we report the SCC of milk samples from five different goat breeds bred in Hungary, measured with two fast methods compared with the results from the reference method. Furthermore, we investigated the applicability and the accuracy of the MT-02 (Agro Legato Ltd., Hungary) instrument. We determined that the White Side test and the instrument MT were suitable for the estimation of possible risks and consequences in the case of the use of high SCC milk before production. The general summarized average milk SCC was 6.64 × 105 ml−1. The highest difference between the results from MT-02 and the fluorometric (reference) method was 5 × 105 ml−1, but it was a singular, extreme value. The r2 of the calculated linear calibration equation was 0.7819; consequently, this method seems to be applicable in the measurement of SCC with MT-02 instrument. Furthermore, the SCC of samples did not differ significantly by genotypes and by seasons (spring: 5.85 × 105 ml−1, autumn: 6.22 × 105 ml−1).

Relationship between mastitis causative pathogens and somatic cell counts in dairy cows

Milk somatic cell count is a key component of national and international regulation for milk quality and an indicator of udder health and of the prevalence of clinical and subclinical mastitis in dairy herds. The objective of this study was to evaluate the presence of mastitis pathogens in milk samples differed by somatic cell count (SCC) in microbiologically positive samples. Also frequency of distribution of samples differed by SCC were studied in non infected samples as well. The milk samples were collected from individual quarters from the dairy farms located in Nitra region with problematic udder health of herd for SCC and bacteriological analysis. Totally, 390 milk samples were examined, and 288 (73.85%) positive milk samples were detected. Four SCC groups of samples (&lt;100, &lt;100&lt;SCC&lt;200, &lt;200&lt;SCC&lt;400 and &gt;400×103/ml) were used to identify presence of microorganisms in positive samples. The most frequently isolated pathogens in samples with high SCC &gt;400×103/ml according to year were Coagulase-negative Staphylococci (29.11 %) in 2012, followed by Staphylococcus aureus (28.0%) in 2010, yeasts (24.05%) in 2012, Escherichia coli (22.78%) in 2012, Bacillus sp. (20%) in 2010 and Pseudomonas aerugenosa (11.88%) in 2011. Coagulase-negative Staphylococci (66.67%) were the predominantly identified in the samples with low SCC &lt;100×103 cells/ml, followed by Bacillus spp (50%), Entrococcus spp. (33.33%) and Staphylococcus aureus (16.67%) and E. coli (16.67%). The results of this study indicated that the SCC of individual milk samples corresponded with the health status of the udder of dairy cows represented by presence of mastitis microorganisms in milk. However, the contamination of milk samples could be also connected with low SCC. On the ohter side the samples with high SCC were found out without presence of microorganism. The further study is needed to identify the reason of high SCC in milk from negative samples.

Bayesian evaluation of budgets for endemic disease control: An example using management changes to reduce milk somatic cell count early in the first lactation of Irish dairy cows

The aim of this research was to determine budgets for specific management interventions to control heifer mastitis in Irish dairy herds as an example of evidence synthesis and 1-step Bayesian micro-simulation in a veterinary context. Budgets were determined for different decision makers based on their willingness to pay. Reducing the prevalence of heifers with a high milk somatic cell count (SCC) early in the first lactation could be achieved through herd level management interventions for pre- and peri-partum heifers, however the cost effectiveness of these interventions is unknown. A synthesis of multiple sources of evidence, accounting for variability and uncertainty in the available data is invaluable to inform decision makers around likely economic outcomes of investing in disease control measures. One analytical approach to this is Bayesian micro-simulation, where the trajectory of different individuals undergoing specific interventions is simulated. The classic micro-simulation framework was extended to encompass synthesis of evidence from 2 separate statistical models and previous research, with the outcome for an individual cow or herd assessed in terms of changes in lifetime milk yield, disposal risk, and likely financial returns conditional on the interventions being simultaneously applied. The 3 interventions tested were storage of bedding inside, decreasing transition yard stocking density, and spreading of bedding evenly in the calving area. Budgets for the interventions were determined based on the minimum expected return on investment, and the probability of the desired outcome. Budgets for interventions to control heifer mastitis were highly dependent on the decision maker's willingness to pay, and hence minimum expected return on investment. Understanding the requirements of decision makers and their rational spending limits would be useful for the development of specific interventions for particular farms to control heifer mastitis, and other endemic diseases.

Níveis de células somáticas sobre a proteólise do queijo Mussarela

Objetivou-se, com a realização deste trabalho, avaliar o efeito do nível de células somáticas sobre a microbiota e a proteólise do queijo Mussarela, durante o período de armazenamento. Foram selecionadas vacas com contagem de células somáticas ≤200mil células/mL; de &gt; 200 a ≤400mil células/mL; de &gt;400mil células/mL a ≤750mil células/mL e &gt;750mil células/mL e que não tinham recebido tratamento com antimicrobianos nos dias que antecederam a coleta da matéria-prima. Os queijos produzidos foram avaliados após 1; 15 e 30 dias de armazenamento para a contagem de coliformes a 35ºC, coliformes a 45ºC, psicrotróficos e bactérias ácido lácticas. Paralelamente, foram determinados os índices de extensão e profundidade da proteólise. O experimento completo foi repetido quatro vezes e o delineamento experimental foi em blocos aleatórios. Na análise estatística, utilizou-se a análise de variância seguida do teste de Tukey, considerando p&lt;0,05 como probabilidade mínima aceitável para diferença entre as médias. O leite com elevada contagem de células somáticas apresentou concentração menor de proteína e maior de nitrogênio não proteico. Observou-se diminuição das bactérias ácido lácticas no queijo elaborado com leite composto de células somáticas &gt;750mil células/mL. Não obstante, ocorreu um aumento significativo na extensão e profundidade da proteólise durante o período de armazenamento, resultados observados nos queijos fabricados com o leite com células somáticas &gt;400mil células/mL. Portanto, para se produzir um queijo Mussarela de boa qualidade torna-se necessário o controle da matéria prima, e esta deve apresentar células somáticas inferiores a 400mil células/mL.

Seasonal and group effects on dairy cow behavior in large yards

In mechanized modern dairy facilities with competitive environments, monitoring behavior provides opportunities to manipulate and optimize the nutritional, health, and social status of high-merit cows. The objective of the current study was to determine seasonal and cow group effects on the eating, ruminating, standing, and lying behaviors of dairy cows in large yards. Seasonal data on various behaviors of lactating cows in different production and lactation stages were collected continuously for 26 months, from December 2006 through February 2008. The herd had approximately 3000 dairy cattle housed in groups within specific yards. A total of 415 multiparous high-producing cows (MH), 166 multiparous medium-producing cows (MM), 166 multiparous low-producing cows (ML), 165 primiparous high-producing cows (PH), 83 fresh cows (FC), 82 fresh heifers (FH), and 82 cows with high milk somatic cell count (HSCC) were monitored. Seasonal eating, ruminating, standing, and lying behaviors were recorded by 4 trained individuals at 1000 hours every week, on 4 days per week. Each activity was expressed as the proportion of cows exhibiting the activity relative to the total number of cows in the yard. Feed was delivered 6 times daily, 4 times as TMR at 0600, 1030, 1300, and 1800, just after milking and twice as alfalfa hay at nighttime. Across all groups, a greater proportion of cows were observed eating during winter (25.7%) than during spring (17.1%), summer (15.4%), and autumn (14.5%). The proportion of cows neither eating nor ruminating was lower in winter (48.1%) than in summer (58.9%) and autumn (58.6%), but similar to spring (53.7%). A greater proportion of cows in the PH (24.6%) and ML (21.3%) groups were observed eating, compared with the MM (15.2%), MH (16.6%), and FC (12.6%) groups. Lying was observed significantly more often in the FC (71%), MM (69.6%), HSCC (65.3%), and MH (64%) groups than in FH (54%), ML (55.7%), and PH (55.7%) groups. A greater proportion of cows were observed ruminating in the MM (31.7%), FC (31.3%), HSCC (28.7%), PH (27.2%), and MH (26.7%) groups, when compared to the FH (20.5%) and ML (22.9%) groups. The HSCC cows were less active in eating and more active in lying than the PH and ML groups. With the remarkably large sample size and prolonged study period, these findings reveal the determining effects of season alongside age, lactation stage, productivity, and-to some extent-mastitis on the eating, ruminating, and resting behaviors of dairy cows in large yard houses.

Physical and chemical characteristics of yoghurt produced from whole milk with different levels of somatic cell counts

For yoghurts were made from milk with different levels of somatic cell count (SCC) (low 95,000 cells ml− 1, intermediate 398,000 cells ml− 1 and high 1,150,000 cells ml− 1). Yoghurt samples were analysed for the degree of proteolysis, lipolysis (free fatty acid (FFA) content), acidity, pH and apparent viscosity on days 1, 14 and 28. The SCC had no significant effect (p>0.05) on either the acidity or the pH of the yoghurt after 1 day of cold storage. However, significant effects (p < 0.05) of SCC were observed after 14 and 28 days of storage. Yoghurt samples made from intermediate and high SCC milk showed higher viscosity (p < 0.05) and lower (p < 0.05) casein content on days 14 and 28 of cold storage than yoghurt made from low SCC milk. High FFA concentrations (p < 0.05) were observed only in yoghurt made from high SCC milk. High SCC in milk increased both proteolysis and lipolysis in yoghurt during storage.

The association between high milk somatic cell counts in the first lactation and somatic cell counts in the second lactation

With the advent of web-based recording and analysis systems, individual cow composite somatic cell count (SCC) data are being increasingly used for decision support in mastitis control at both the individual cow and herd level. SCC data from first and second lactation dairy cows (n=1912) from 12 farms were analysed using multinomial logistic regression to investigate possible associations between high SCC patterns in the first lactation and the subsequent lactation. Animals with three non-consecutive counts >200,000 cells/mL in their first lactation were significantly more likely to have three non-consecutive counts >200,000 cells/mL (OR 3.11; 95% CI 1.72-5.62) or three consecutive counts >200,000 cells/mL (OR 2.00; 95% CI 1.09-3.68) in their second lactation. Similarly animals with three consecutive counts >200,000 cells/mL in their first lactation were significantly more likely to have three non-consecutive counts >200,000 cells/mL (OR 1.90; 95% CI 1.13-3.19) or three consecutive counts >200,000 cells/mL (OR 4.14; 95% CI 2.81-6.08) in their second lactation. These findings suggest that patterns established in the first lactation may have an impact on udder health in the subsequent lactation. However, simulation modelling of positive predictive values for the first lactation cell count patterns as predictors of second lactation patterns demonstrated that, at prevalences likely to be encountered on UK dairy farms, the associations were not a sufficient basis for major management decisions such as culling.

Outbreak of bovine clinical mastitis caused by Mycoplasma bovis in a North Italian herd

This report describes an outbreak of Mycoplasma bovis mastitis affecting 45 cows in a herd of 122 dairy cattle in Northern Italy. Clinically, the outbreak was characterized by agalactia, multiple swollen and painless quarters, high milk somatic cell count and unresponsiveness to conventional antibiotic therapy. M. bovis was isolated from the milk samples of all the 32 affected cows tested and from the mammary tissue of three affected cows that underwent necropsy. No other pathogens were isolated from these samples. Lesions in two of the necropsied cows were characterized by mild chronic suppurative mastitis and galactophoritis. The other necropsied cow showed a chronic necrosuppurative and pyogranulamaous galactophoritis, a condition not previously associated with M. bovis. M. bovis was detected immunohistochemically in the lumen of the affected mammary ducts suggesting that ascending infection via the teat canal was the likely route of transmission. No other intralesional pathogens were demonstrated microscopically.

Short communication: Relationships between α-lactalbumin and quality traits in bulk milk

The main objective of this study was to investigate whether the α-lactalbumin (α-LA) content of bulk milk is related with some known inflammatory markers and milk quality traits. An additional objective was to study whether combining α-LA, haptoglobin (Hp), and serum amyloid A (SAA) in an acute phase index (API) could be useful as an alternative marker for bulk milk quality. For the dairy industry, it is of great importance to receive high quality bulk milk for manufacture of liquid milk and dairy products. The somatic cell count (SCC) is currently used as an indirect marker for bulk milk quality, but because it is somewhat insensitive and unspecific, interest exists in alternative markers. Bulk milk samples were analyzed for α-LA, SCC, polymorphonuclear leukocyte count, Hp, SAA, fat, lactose, total protein and casein contents, casein number, protein composition, proteolysis, and coagulating properties. No significant differences were found in SCC, polymorphonuclear leukocyte count, Hp, or SAA between milk samples containing low, medium, or high concentrations of α-LA. Differences between α-LA groups were, however, found in some milk quality traits because high α-LA concentration was related to low concentrations of αS1-, αS2-, and β-caseins and high concentrations of lactose and β-lactoglobulin. A high API was related to low lactose content and casein number. Samples with high SCC contained less casein and had a lower casein number than milk with a low SCC, and proteolysis was significantly higher in high SCC milk than in low SCC milk. Neither α-LA nor API proved to be a better marker than SCC for the quality traits investigated, and α-LA was not considered to be a useful inflammatory marker in bulk milk.

Treat the Treatable and Manage the Rest

Farm income for many dairies can be improved by increasing the value of milk by taking advantage of somatic cell count (SCC) based milk quality premiums and reducing treatment costs. Recent research has shown that the likelihood of an animal to have a repeat case of clinical mastitis after a first clinical case is about 30%. Pathogen-based treatment protocols should provide a science-based process for selecting the most appropriate treatment and duration of treatment resulting in high bacteriological cure rates and fewer repeated clinical cases. Many infections caused by gram-positive organisms, particularly streptococcal species, respond well to appropriate treatment; cure rates can approach 80% or higher. Most gram-negative pathogens respond poorly to intramammary treatment. Mastitis caused by other pathogens, such as yeast, are exacerbated by intramammary treatment and others, like Prototheca species and mycoplasma, have no known treatment. Generally the normal distribution of mastitis pathogens is about one-third gram-positive organisms, one-third gram-negative pathogens, and one-third no growth culture result, suggesting that pathogen-based treatment protocols have the potential for substantial savings.&#x0D; Duration of treatment for specific mastitis pathogens should have a major influence on cure rates, particularly for a range of streptococcal species and select Staphylococcus aureus infections.&#x0D; There are also opportunities to manage chronic subclinical infections which are often the major contributors to the bulk tank SCC. Milk from high cell count cows can be managed through treatment, segregation of high SCC milk at the quarter level, quarter dry-off, and culling.