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22 Cards in this Set
- Front
- Back
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What should you give to the cow before starting teat surgery?
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Epidural Analgesia
•Xylazine 0.04-0.07 mg/kg •make up to 5 mL with sterile water or 2% lignocaine •takes 20-30 min to reach full analgesiaOedema |
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when is the best time to perform teat surgery?
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•Surgery should ALWAYS be donewithin 12 hours of wound occurring -preferably within 1-2 hours
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What sutures and patterns shoul dyou consider for teat surgery?
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•2-0 or 3-0 absorbable suture material with a “swagged” on round-bodied needle
•Sutures close together (continuous pattern) •Skin sutures •Fine to extra fine “Vetafil” or nylon. Use a vertical/ horizontal mattress/ cruciate pattern ** always check for leaks after suturing using intramammary antibiotics (blue dye) |
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how does teat fistulas occur?
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•Result of failed healing after surgery or lacerations not treated
•Poor closure/ breakdown of the mucosal layer in repaired teat injuries •Occasionally congenital teat fistulas occur •Quarter predisposed to mastitis |
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Supernumerary Teats: how do you treat it?
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•Best removed in the first week of life (snip off)
•Remove before animal starts lactating •Adult animals/ heifers •Ensure quarter is not producing milk •Mild IV sedation •Regional analgesia around base of teat •Crush teat close to base with artery clamps •Remove teat below crush line with scalpel/ scissors •Suture wound closed. Remove in 14 days |
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how do you treat leaking teats?
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Inject sclerosing agent/ sterile mineral oil at 4+ equidistant points in sphincter
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what is lactoliths?
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•Soft mineralised pea shaped deposits in teat canal
•May not cause a blockage at every milking |
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what is the difference between subclinical mastitis and mastitis?
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ChronicClinical Mastitis
5 •Heat, pain, swelling or •Induration of the udder with no obvious signs •Abnormal milk, yield and quality also affected •Systemic signs Sub clinical mastitis: One or more quarters affected with a pathogen without clinical signs Increase in leucocytes (somatic cells) in the milk from that quarter |
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What are some cow risk factors for mastitis?
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•Cows dripping milk before calving or upon
entry to the milking shed •Calving •Heifers vs. older animals •Friesians > Jersey or crossbreds •Calving > 18 days after planned start of calving •High SCC or clinical mastitis in previous lactation •Infection, either at drying off or new subclinical infection over the dry period •Teat damage •Poor udder conformation •Low body condition score •Ketosis •Low vitamin E concentrations •Increasing milk production and peak milk flow |
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Describe staphylococcus infections on teats 4.
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Contagious, isolated from udder and skin of teat, less commonly colostrum
•Colonise gland tissue •Usually spread from infected glands of cows at milking •Also isolated from milkers hands and can survive between milkings (use gloves to reduce spread of infection) |
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HOw does staphylococcus contribute to mastitis and production?
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Significant damage to milk producing tissue –clinical signs vary from subclinical to gangrenous mastitis
•Abscess formation –difficult to treat •Decreases milk production •High bacteria counts in bulk milk are generally not seen22Staph |
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Coagulase negative Staphylococci (CNS): what does it cause, where does it originate? How do you control it?
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Mild inflammation of the mammary gland
•“Skin flora opportunists” –often isolated from eg vagina, teat skin and canal •Leading cause of IMI in first calf heifers •New infections often start in the dry period •Highest prevalence at calving, ↓during first month of lactation –spontaneous elimination •Teat dipping reduces new infection rate |
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Streptococcus agalactiae: how can you detect it?
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Obligate parasite of the mammary gland, can survive for limited time in the environment
•Classified as contagious because of the cow-cow spread at milking •Decreased milk production •High cell counts (suspect S. agalactiaeif BMCC > 400,000) but few clinical signs •May see high bacterial counts when infected udders shed bacteria |
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Does Streptococcus agalactiae cause clinical signs?
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•Rarely causes severe clinical disease -can cause extensive scarring of the quarter
•Somatic cell counts (SCC) in the affected udder usually decrease significantly within a few weeks of elimination of the pathogen from the gland •Acute, subacute and subclinical forms can be seen |
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Streptococcus uberis: where is it originat efrom?
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Mainly environmental pathogen, BUT it may also be transmitted quarter to quarter under the correct conditions
•Lying and bedding areas provide most challenge to the teat end –found in rumen and faecal samples. Faecal contamination of the udder a problem. •Exposure during or between milkings, during the dry period and prior to parturition in first lactation heifers. |
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What is the most common organism causing coliform mastitis
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Escherichia coli
•The most common organism causing coliform mastitis •Environmental pathogen (survive for long periods) •Most strains are of low virulence, but may cause opportunistic infections in extra intestinal locations such as the mammary gland and urinary tract |
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How is ecoli transmitted?
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Soil, water, manure and vegetable matter are important sources of E. coli.
•Coliforms are transmitted to the cow’s teat between milking, BUT milking machine liner + faeces can act as a vector for transmission. •Milking cows with wet udders = ↑ incidence of coliform mastitis •Seasonal incidence, more common in housed animals than pasture-based herds •More common in dry or early lactation cows |
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how do u differentiate subclinical and chronic mastitis?
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QuarterSubclinical mastitis
•No clinical signs •Elevated leucocyte (somatic cell) counts detected with Rapid Mastitis Test (RMT) or Somatic Cell Counting of milk samples •SCC usually between 250,000 to 1,000,000 cells/ml of milk. •Animals are a reservoir of potential infection for clean animals Chronic mastitis •Milk yield changes and udder damage •Usually starts as an acute mastitis •↓ Milk production (quarter may go dry) •Hypertrophy or atrophy of the quarter •The quarter can return to apparent normality but may see relapses with another bout of acute mastitis (esp S. aureus) |
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How do u test for mastitis?
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Milk sampling and testing
•Detection of somatic cell levels in the milk •Rapid Mastitis Teat (RMT) -a detergent is used to bind with cell proteins released by the degeneration of leucocytes. Cow side test. •Somatic cell counters. Not a cow side test. •Tests which measure alterations in milk composition •Electrical conductivity measurements -high cell count = high conductivity. Cow side test •pH determination. Mastitic milk has an increased pH. Cow side test •Tests which measure cell enzymes in milk (Leukocytes release enzymes in milk when present) •“NaGase” test measures the level of N-acetyl-B-D glucosaminidase a cell associated enzyme. Not a cow side test |
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When do you use DCT?
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If using selective DCT, treat the following:
•Previous and present clinical cases •High SCC (>150,000) cows •Light weight/ CS heifers •Low producers (< 5 litres) Treat the remainder with teat seal |
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If a herd –
1.Has fewer that 3 ICC for each cow 2.Has S. agalactiaepresent on culture 3.30% of cows have peak ICCCs>250,000 cells/mL what therapy will you recommend>? |
Use blanket antibiotic DCT
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How long do linersreally last?
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They last for 2000-2500cow milkings. Then:
•milking speed reduces •under-milking increases •teat end damage increases •cup slips increase •bacterial spread increases |
