The survey on milk biochemical changes in subclinical mastitis

Mastitis A disease complex resulting from

any condition that induces inflammation of the mammary gland

Bruising of the udder Introduction of a foreign chemical into the

mammary gland Invasion of the mammary gland by

pathogenic/environmental microorganisms

What causes mastitis ?

Bacteria ( ~ 70%) Yeasts and molds ( ~ 2%) Unknown ( ~ 28%)

physical trauma weather extremes

Where do these organisms come from ?

Infected udder Environment

bedding soil water manure

Replacement animals

Economic Loses Due to Mastitis$2.8 billion/year

Expenditures Death/Premature

Culling of Cows Treatment and Vet

Expenses Discarded Milk Unobtained Milk

Production

% of Total

14 8 8

70 100

What are the health concerns of mastitis ?

Animal health Loss of functional quarter Lowered milk production Death of cow

Human health Poor quality milk antibiotic residues in milk

Mastitis Terminology

Clinical – Presence of clinical signs Signs of infection Udder shows signs of inflammation

(Rewdness, swollen, tender, hard, etc.) Milk is abnormal

• Flecks, gargot (clots), off color, bloody

• Goal <2% per month

Subclinical No evidence of abnormality except milk

positive on special tests.• CMT, SCC, Sterile milk culture, etc.

Mastitis Terminology

Acute Rapid and severe onset High temperature Serious condition

Chronic Persistent subclinical form

How severe can mastitis be ? Subclinical Mastitis

~ 90 -95% of all mastitis cases

Udder appears normal

Milk appears normal

Elevated SCC (score 3-5)

Lowered milk output (~ 10%)

Longer duration

Clinical Mastitis ~ 5 - 10% of all mastitis cases Inflamed udder Clumps and clots in milk Acute type

major type of clinical mastitis bad milk loss of appetite depression prompt attention needed

Chronic type bad milk cow appears healthy

Mastitis in a Herd

Clinical

Subclinical

Process of infectionOrganisms invade the udder through

teat canal

Migrate up the teat canal and colonize the

secretory cells

Colonized organisms produce toxic substances

harmful to the milk producing cells

The cow’s immune system send white blood cells (Somatic cells) to fight the organisms

recovery clinical subclinical

Materials and Methods

Animals were selected from 4 Holstein dairy herds located in Shiraz.

Cows were in the third lactation and fed the same as each other

CMT used as a screening test for subclinical mastitis

Milk were sampled from 30 cows with subclinical mastitis as well as from 30 healthy controls

CMT

CMTScore Description

SCCcells/ml

MastitisDiagnosis

- (Negative) Mixture remains liquid with no evidence of thickening or formation of a precipitate.

< 200,000 No mastitis

T (Trace) Slight thickening that tends to disappear with continued movement of the paddle.

150,000 to 500,000

Suspicious

1 (Weak) Distinct thickening, but no tendency toward gel formation. Thickening may disappear after prolonged rotation of the paddle.

400,000 to 1,500,000

Suspicious

2 (Distinct) Mixture thickens immediately. With continued rotation of paddle, liquid moves towards the center, leaving the bottom of the outer edge of the cup exposed.

800,000 to 5,000,000

Mastitis

3 (Strong) A distinct gel forms which tends to adhere to the bottom of the paddle and during swirling a distinct mass forms.

Over 5,000,000

Mastitis

Records of 3 months production of each cows were used for calculating Milk Yield

Moisture was determined by oven dehydration pH was determined using a Metrohm pH-

meter Protein was measured by Kjeldahl method Fat was determined by Gerber method Lactose was determined by HPLC Na and K contents were measured by flame

photometry Ca and P contents were measured by atomic

absorption spectophotometry Cl content was measured by

spectrophotometer (using Pars Azmun kit) Vitamin C and E were measured by HPLC Catalase activity was determined by

monitoring H2O2 loss (measuring the absorbance at 240 nm during the initial 30 s)

Statistical analysis

Data were analysed by Paired sample’s T test (SPSS software, version 16)

Results and Discussion

Factor Cow

Milk yield,kg/90

d

Water (%) pH Protein (%) Fat (%)

Healthy 4128 ± 118 86.81 ± 0.06 6.63 ± 0.03 3.28 ± 0.15 4.55 ± 0.74 Subclinial mastitis

3589 ± 134 87.67 ± 0.07 6.75 ± 0.04 4.25 ± 0.67 3.21 ± 0.48

Factor Cow

Lactose (%) Na (mg/dl) K (mg/dl) P(mg/dl) Ca (mg/dl)

Healthy 4.93 ± 0.16 46.53 ± 7.67 156.39 ± 11.71 29.49 ± 1.06 119.52 ± 2.66 Subclinial mastitis

4.38 ± 0.22 78.46 ± 8.14 118.72 ± 9.36 23.64 ± 0.87 97.84 ± 1.91

Factor Cow

Cl (mg/dl) Vit C (mg/L) Vit E (µg/L) Catalase (U/ml)

Healthy 100.56 ± 3.49 19.14 ± 1.23 946.37 ± 10.56 1.95 ± 0.08 Subclinial mastitis

183.74 ± 5.77 18.43 ± 0.93 904.18 ± 21.04 3.53 ± 0.21

Changes in Mammary Tissue with Mastitis