Somatic Cell Count and Relationship to Milk Losses
Records to Keep Bulk Tank SCCBulk Tank SCC DHIA DataDHIA Data Bulk Tank CulturesBulk Tank Cultures Treatment RecordsTreatment Records Individual Cow CulturesIndividual Cow Cultures
Contagious Organisms Streptococcus agalactiaeStreptococcus agalactiae Responds to treatment Staphylococcus aureusStaphylococcus aureus Does not respond well to treatment Mycoplasma spp.Mycoplasma spp. Uncommon in MN Does not respond to treatment
Environmental Organisms Non ag strepNon ag strep Can be high in bedding Can act chronic - particularly Strep uberius Staph speciesStaph species Primarily Staph Epidermidis - normal inhabitant of skin ColiformColiform E Coli - source is feces Klebsiella - Source can be bedding Culture Bedding - < 1M / gCulture Bedding - < 1M / g
Gram Positive Mastitis Gram (+) become chronic if not treated with the right antibiotic NMC recommendations -- “treat Gram (+) lactating mastitis early”
Gram Negative Mastitis University research -- coliform bacteria gone by the time we see abnormal milk Neutrophils (white blood cells) clear infection Clinical signs due to endotoxins (dead bacteria) Antibiotic treatment only supportive
Strep. Ag. Problem Responds well to treatmentResponds well to treatment Identify infected CowsIdentify infected Cows Work with Veterinarian on Treatment/CultureWork with Veterinarian on Treatment/CultureProtocol Focus on teat dip coverage
S. Aureus. Problem Does not respond well to treatmentDoes not respond well to treatment ID infected Cows (ear tags, ear notches, brand)ID infected Cows (ear tags, ear notches, brand) Segregate and milk last to prevent spreadSegregate and milk last to prevent spread Infections caught early may respond to treatmentInfections caught early may respond to treatment Focus on teat dip coverage to prevent colonizationFocus on teat dip coverage to prevent colonization
Environmental Problem Varied response to treatmentVaried response to treatment Often caused by milking wet, dirty teatsOften caused by milking wet, dirty teats Focus on Teat Ends!!!!Focus on Teat Ends!!!! Focus on clean, dry comfortable environmentFocus on clean, dry comfortable environment
Adapted from the DHI Somatic Cell Reports Annual timeline -- Where do infections occur? When are cows being infected?
Early Lactation = Dry Cow Problem Mid or Late Lactation = Cow Prep or Lactation Housing Problem
Is it only a few cows contributing to the the problem DHI Records
Linear Evaluation of a Herd with a Contagious Mastitis Problem
Linear Evaluation of a Herd with an Environmental Mastitis Problem
Number infections - Count of all infected milking cows Fresh infections - Count of infected fresh cows Number new infections - Count of cows with new infection Percent new infections - Percent cows exposed that got infected -- end page one
Production Averages What is the trend in fresh infection rate? (frsh inf/frsh cows) What is the trend for number of infections? What is the trend for new infection rate?
If New Infection Rate is: Less than 7% - SCC will decrease 7-12% - SCC will remain the same Greater than 12% will tend to increase Reneau and Farnsworth, Personal Comm. New Infection Rate
Mastitis Treatment Strategies Pathogen Profiling (cultures) Grading mastitis cases by severity Using cost-effective treatment protocols Monitoring relapses and SCC
Clinical Mastitis Grading System Grade 1 –mild (milk only - clots and flakes) Grade 2 –moderate (milk and udder) Grade 3 –severe (milk, udder and cow-systemic)
Protocol for SCC Problem 1. Determine the Organism Bulk Tank SCC Bulk Tank SCC Individual Cow Cultures Individual Cow Cultures 2. When are cows getting infected? Hfrs vs. Cows? Hfrs vs. Cows? Dry Period? Dry Period? During lactation During lactation 3. Culturing Plan Bulk Tank Cultures Bulk Tank Cultures New infections (linear > 4) New infections (linear > 4) New clinical infections New clinical infections 4 Treatment Protocol 5. Monitoring Plan
Udder Health Monitor Goals 1. Bulk Tank Cultures Strep. Ag. = 0 Strep. Ag. = 0 Mycoplasma = 0 Mycoplasma = 0 Others in Low Category Others in Low Category 2. Bulk Tank Somatic Cell Count goal < 200,000 goal < 200,000
3. DHI Linear Score Goals Wallace, 2000 Udder Health Monitor Goals
4. New infection rate goal < 7%/month goal < 7%/month 5. New infection rate on fresh cows goal < 20%/month goal < 20%/month 6. Clinical mastitis cases < 2% per month < 2% per month 7. Mastitis Culling Rate < 10% per year < 10% per year (Wallace, 2000) Udder Health Monitor Goals
Management Practices Associated with “Low” (<150,000) Bulk Tank SCC cleaner free stalls use more bedding cleaner drinking cups remove udder hair dry cows checked for mastitis daily cleaner calving pens fresh cows kept out of bulk tank longer.
Management Practices Associated with “Low” (<150,000) Bulk Tank SCC more consistent and longer use of teat dipping more consistent and longer use of dry cow therapy clinical cases treated for longer duration more apt to provide nutrient supplements.
Bottom Line Use records to determine: who, what when where and why Set up protocols based on organisms Cleanliness is next to godliness Low SCC (<200,000) is very achievable and profitable
Credits Jim Salfer Text D. Weinand, R.J. Erskine, G. Neubauer, Minnesota DHIA