managing mastitis in bred heifers
TRANSCRIPT
Managing Mastitis in Bred Heifers S.C. Nickerson, UGA, [email protected]
Goal: Improve milk quantity & quality Mastitis management in heifers is part of this goal Heifers: Calve with maximum yield and low SCC
Mastitis!diminishes
yield/quality
Supported by USDA-NIFA Grant no. 2013-68004-20424
•Prevalence of intramammary infection
•Treatment with antibiotics
•Use of teat seals to prevent new cases
•Horn fly control to ↓ spread
•Vaccination ↑ immunity
•Feed additives: improve animal health
Mastitis in Heifers: Outline
Prevention:
Mastitis is not noticed until freshening or at the first clinical flare-up
during lactation.
Young dairy heifers areregarded as uninfectedFuture milking herd!(Also need an udder health program)
~20-30% of heifers: S. aureusSCC >10 million/ml
(Few clinical symptoms)
Breeding age: 12-15 mo and older
>75% of heifers: subclinical mastitis
Clinical Subclinical
Neonatal Prepubertal
Breeding agePregnant2 - 2.5 yr (¼ - ½ lifetime!)
NO MASTITIS CONTROL ↓ MILK YIELD ↑ SCC!!!!!!!
Future milking herd! (Also need an udder health program)
Heifers exposed to mastitis bacteria at a young age
←Colonize teats
Keratin plug
Intramammary infection
Bacteria
How do heifers get mastitis?
Teat
Staph. aureus
75% of heifers may be infected in 60% of quarters; Staph. aureus is a major problem.
Mammary quarter infection rate: 60%
All infections associated with elevated somatic cell counts (SCC).
Staph. aureus
40%uninfected
60%infected
↓ Yield!
Reduced secretory potential
Infected rear quarter Uninfected front quarter
Scar tissue formation in response to Staph. aureus
Lower yield during 1st lactationand spread to the lactating herd
Cross-section of a heifer’sudder infused w/ green dye
10% lessmilk
20,000 lbvs.
22,000 lb
What happens inside an infected quarter?
FrontRear
Greatest development of milk-producing tissuesis during 1st pregnancy
Protection from mastitis bacteriaInsure maximum milk production
Infected quarters should be treatedIf mastitis is suspected in heifers… Lactating and dry cow intramammary infusion products
Dry cow product use in heifers• Cefa-Dri• Tomorrow• Dry-clox• Albadry Plus• Biodry• Quartermaster• Orbenin-DC• Spectramast DC
Treat prior to 30 days prepartum(avoid residues)
Non-lactating cow
**Sanitize teat orifice, use partial insertion technique, dip teats
*Cure rate is 90 - 100% when treated during pregnancy.
*SCC significantly reduced 50% at calving vs. controls.
*Milk production increased by ~10% over the controls.
*Reduced spread of Staph. aureus to the lactating herd.
Dry cow therapy in heifers:
When is best time to treat?Pregnancy checks
Hoof trimming
Moving to close-up lot; run through chute/treatExtra-label: Valid CPR
Lactating Cow Products• Cefa-Lak• Today• Hetacin-K• Albacillin• Pirsue• Amoxi-Mast• Dariclox• Spectramast LC
~14 days prepartumAny sooner results in antibiotic residues
Lactating cow
73% Holstein heifers infected 2 wk prepartum Treated with:
Penicillin/novobiocin or PirlimycinDetermined cures at calving:
Oliver et al., 2004
Albacillin: 76% cure rate; Pirsue: 59% cure rate
96% of Jersey heifers infected 2 wk prepartumTreated with:
Penicillin/novobiocin or PirlimycinDetermined cures at calving:
Albacillin: 75% cure rate; Pirsue: 87% cure rateTreated heifers produced 10% more milk Whether dry / lactating products are used, follow proper infusion method:
Full Insertion: Stretches sphincter Dilates teat canal Removes keratin
Introduces bacteria
Partial Insertion: Maintains integrity Minimizes bacterial entry into the gland
Environ.bacteria
E. coliProtothecaNocardiaT. pyogenesYeast
Partial insertion(2-3 mm)
Fullinsertion
Bacteria
Prevention…
Use of Internal Teat Sealants Prepartum:
Physical barrier to Bacteria
• Bismuth/paraffin based • Infused 30 d prepartum• Removed at 1st milking Orbeseal™
Bismuth subnitrate/mineral oil
Teatseal®
Bismuth subnitrate/paraffin oil
4-fold reduction in clinical S. uberis infections within 14 days of calving.
What about teat seal AND antibiotic?Does the combination work
better than either alonein dairy heifers?
1.Untreated2.Antibiotic DCT 3.Teat seal4.DCT + teat seal
12 3
4
Results (n=38) at calving demonstrated….
30-60 d prepartum:
Cure rates and prevention rates for untreated qtrs & qtrs treated withDCT and/or teat seal in 38 heifers
Untreated
Antibiotic
Teatseal
Anti + seal
Untreated
Antibiotic
Teatseal
Anti + seal
0
20
40
60
80
100
120
58.3
100
75
100 96.2 92.8 96.2 93.1
Cure rate Prevention rate
a
b
ab
b a aaa
SCC: 1,488,000 Ave SCC: 464,000 No differences among tmtWhy bother treating at all?
3 out of 4 quarters (75%)may be infected
w/ bacteria
UninfectedInfected
Treat all quarters with 1) DCT to cure existing IMI &2) Teat seal to prevent the establishment of new IMI.Successful treatment will lower SCC at calving time.
Proper teat seal infusion:
1. Compress area at base of teat with hand.
2. Insert cannula using the partial insertion method
3. Slowly infuse contents so seal remains in teat
Teat seal
1.
2.
If teat cistern is open to glandcistern, and seal is jetted intoteat, it may be placed high inthe quarter and milk out for days or weeks after calving.
←Teat cistern
←Gland cistern
Horn flies not only pester heifers by feasting on blood drawn from animals’ backs…
Role of fly control
Horn flyHaematobia irritans
3-month-old heiferS. aureus-infected quarter
Bred heifer
Front teats
Flies also attack heifers’ teats, causing mastitis
Bacteria
Horn flies live solelyon blood from cows.Lifespan: 3-4 weeks
Capi
llary
Irritation andscab formation
Mastitis
Score 2Mastitis
Score 3Mastitis
Score 1Healthy
If heifers’ teat scores are not healthy (Score 1), then a fly problem exists,and teat lesions (Scores 2 and 3) are associated with mastitis.
Teat condition: a good barometer for fly control
Herds with fly control programs have healthier teats and less mastitis
Percentages of heifers with mastitis in herds with and without fly control
(Foggers, bait, pour-ons, dust, sprays, ear tags)
% of heifers
10-fold
• Use of pour-ons reduces fly populations• (Every 2 wk – intensive)
Horn Fly Control?
Insecticidal pour-on (Eprinex) +ear tag (Patriot) reduced flies and
↓ Staph. aureus mastitis by 83%over a 6-month period
Pour-on
IGR
Fly lays its eggs
Insect Growth Regulators(IGR; ClariFly® Larvacide)
Insect Growth Regulators
Horn FlyLife Cycle
Larvae consume IGR
Pupae
Larvacide (IGR)
Maggots
Eggs in manure
Eggs hatchFly control: - Pour-on - Ear tags - IGRVery effective
Reduction in fly population
Increasing antibodytiters to prevent newS. aureus infections
Lysigin, AKASomatostaph
Preventing mastitis by immunization
Can heifers be vaccinated against Staph. aureus mastitis?
James River Correctional Center
• 120-cow Holstein herd• 22,000 lb milk• Average SCC: 200,000/ml• ~20% S. aureus infection rate in heifers• Prevention of mastitis via vaccination?• 106 heifers 6-12 mo allotted to vaccinated
and control groups
(53 heifers/group)
Immunization ScheduleAt 6-12 mo14 days laterAt 6-mo intervalsPre-calving
Lysigin
Monitored level of S. aureusmastitis after freshening
Semimembranosus
Percentages of heifers freshening with Staph. aureus infections.
0
5
10
15
20
25
30
35
40
13.3
34
Vaccinated Control
60.9% Reduction (P<0.001)
Perc
enta
ge o
f hei
fers
with
mas
titis
50% reduction in SCC
8.6% increase in prod.
Minimize spread to milking herd
Immunization: +....in heifers
Other options toboost immunity....Diet/ration?
Boosting Immune System:Dietary Supplementation
Selenium Vitamin EBeta caroteneVitamin ACopperZinc
Promote leukocyte antibacterial activity
Reduced staphylococcal and coliform mastitis at calving & lowered SCC
Se & Vitamin E in heifers:
Supplementation 60 days prepartum
Weiss, 2002
←Periparturient
Rate of new infection
LactationCalving
Periparturientperiod
Period ofImmunosuppression
(Cortisol)
2-4 wk prepartumto 2 wk postpartum
(Innate immunity suppressed)Reduced neutrophil activity
Mastitis increases around time of calvingInnate immunity: most important defense of the mammary gland
Relies heavily on the bactericidal function of WBC migrating from the blood
WBC function is compromised during the periods of immunosuppression: Cortisol
If WBC function could be enhanced, cows could better resist mammary infection Enhancing WBC? - Diet: Se + Vit E - Diet: OmniGen?
PARTURITION
OmniGen-AF® enhanced immune status & reduced mastitis at calving
Daily supplementation for 60 d prepartum; at calving:
Enhanced L-Selectin receptor activity on PMN and Monocytes
Increased phagocytosis of S. aureus and E. coli by leukocytes
Decreased free radical generation by PMN (Antioxidant?)
Fewer health events (RP, DA, ketosis, udder edema, death)
Fewer new intramammary infections: no reduction in SCC
At calving:
1st calf heifers4g/100lb/day
Concluded: Supplemented heifers calved healthier vs controls
Dietary supplements to boost immunity at calving: Beneficial
Young calves
Pregnant
Close-ups
All susceptible to mastitis!• Need a prevention program • Need a treatment program
• Freshen free of mastitis • Low somatic cell counts• Maximum milk production $$
Goal
Fly controlVaccinationTeat seal +/orDietary suppl.
Dry cow tmt/ Lact. cow tmt
Future milking herd:
Preventionnot 100%
SUMMARY
$Huge Investment$