Transcript File

Holstein/Friesian
• from Holland via USA
• They weigh 680 kg when
mature.
• Bred to produce higher
milk and protein yields
than any other breed
• Make good use of grass
for milk production
• Sensitive to cold wet
conditions and need early
winter housing
1
British Friesian
• Slightly smaller than Holsteins
• Carry more flesh
• Good fertility
2
Other Dairy Breeds
Ayrshire
• Easy calving and
longevity
3
Brown Swiss
• Longevity
• Good feet and legs
• Strong and healthy
4
Guernsey
• Efficient converter of
feed to milk
• Early maturity
• Milk is a distinctive
golden colour.
• Easy calving
5
Jersey
• Milk is high and fat and
protein but lower yield
than Holstein-Friesian
• Low maintenance cost
• Easy calving
• High fertility
• Longevity
• Less prone to lameness
6
Milking Shorthorn
• red, red and white,
white or roan, a very
close mixture of red
and white, and found
in no other breed of
cattle.
• Ease of calving
• Good feet
• Longevity
7
Montbéliarde
• Light red and
white, white head
• Dual purpose
• Hardy
• Resistance to
mastitis
8
Norwegian Red
• Calving ease
• High fertility
• High fat and protein
milk
• Higher Mastitis
resistance
• Choice of Polled or
Horned
• Hardy hooves
9
Normande
• Dual purpose
• Good growth rate in calves
• Ideal for dairy
crossbreeding
• Fertility
• Calving ease
• Strength
• High percentage yield at
slaughter
10
Jersey X Holstein cross
• Smaller, lighter
and darker in
colour than
Holstein
• Lower milk volume
• Higher milk solids
• Efficient converter
of grass
11
12
Age (yr) Lactation no.
Lactation yield as
% of maximum
2
1
75
3
2
85
4
3
90
5
4
95
6
5
100
Cows produce first calf at 2 years.
Reach maximum yield at their fifth lactation
13
Breeds of cattle – contrast in milk
composition (%)
Breed
Milk (kg) Fat (kg)
Protein (kg) % fat
Jersey
4797
243
180
5.06
Holstein/ 6970
Freisian
264
234
3.79
14
Lactating
• When lactating a cow can be either
pregnant or non-pregnant.
• When dry  pregnant.
• Try to get the cow to complete the cycle in
one year.
• The length of the cycle depends on how
long it takes for her to get pregnant again.
15
1 year calving interval
• 305 days of lactation
• 60 days of a dry period
• Cow carries calf for 9 ½ months (283-286 days)
• 365 – 286 = 82 days
• Need to be mated 82 days after calving
• If it goes over 82 days, it will go over the 1 year cycle.
16
Lactation curve of a machine milked cow
Milk yield
Early
lactation
Mid lactation
Late lactation
Dry
period
0 weeks:
calving
These changes are due to changes in activities and changes
in the number of cells in the mammary glands
17
Milking machine versus cow with calf
• Yield is in response to a challenge
• More milk asked for more milk will be provided
Milk yields/
day (Kg)
Milk machine
Cow with calf
Time (months)
18
Factors influencing milk yield
• Breed, weight at calving
• Age
• Frequency of milking
• Dry period
19
Factors influencing milk composition
• Breed
• Feed
– Good grass
increases milk,
fat and protein
– Fibre needed for
fat production
• Stage of lactation
• Milking interval
20
Feeding for milk quality
•
•
•
•
High fibre feed increases butterfat content
Leafy grass increases protein
Good quality feed
Control mastitis
21
Grass Budgeting
• A grass budget aims to balance the grass
supply with the grass requirement or "herd
demand".
• Measure grass cover
• Estimate DM cover and grazing
requirement
22
Estimating Grass Cover
23
24
Grass Budgeting
25
26
27
Grass budgeting
• Example
– A farmer has 50 cows grazing on a 0.5 ha
paddock. Each cow consumes 15 kg DM/day.
How long can the cows be left in the paddock
to graze it completely? (i.e. a stubble height of
4 cm).
28
•
•
•
•
•
•
•
•
Mass of grass removed from a 0.25 m2 quadrat = 200 g
DM = 18%
200 g x 0.18 = 36 g DM or 0.036 kg DM/0.25 m2
0.036 kg DM x 4 = 0.144 kg DM/m2
0.5 ha = 5000 m2
0.144 kg DM x 5000 = 720 kg DM/0.5 ha
720/50 = 14.4 kg DM/cow
At 15 kg DM intake/day, (14.4/15) x (100/1) = 96% of
their daily intake
• 24 hours x 0.96 = 23.04 hours
• 23 hours grazing left
29
Milk Quality Standards
2. Somatic Cell Count (SCC):
– Count of white blood cells
– High SCC indicates presence of sub clinical
mastitis
– SCC must mot exceed 400,000 on a three
month geometric mean
http://www.fsai.ie/uploadedFiles/Reg853_2004(1).pdf
30
Milk Quality Standards
3. Thermoduric Test:
– Number of thermo-resistant bacteria must
not be > 1000/ml
4. Milk temperature:
– Milk only collected from refrigerated tanks
and be < 6°C
5. Antibiotic test
– Routine test for the presence of antibiotics
http://www.fsai.ie/uploadedFiles/Reg853_2004(1).pdf
31
Milk Quality Standards
6. Excess water:
7. Sediment test:
– Milk must be free from physical particles and
sediment
– Cow’s udders and teats must be clean at
milking time and milk filtered
–
Biosecurity for diseased animals
http://www.fsai.ie/uploadedFiles/Reg853_2004(1).pdf
32
The Milking Machine
• Extracts milk from the cow by vacuum.
• Apply constant vacuum to the end of the teat to suck the milk
out, convey it to a suitable container, to give a periodic squeeze
applied externally to the whole of the teat to maintain blood
circulation.
• A milking machine installation consists of a pipework system
linking various vessels and other components which together
provide the flow paths for air and milk.
• The forces are maintained by a vacuum.
• Atmospheric pressure forces air, and intra-mammary milk
pressure which forces milk, into the system and the
combination of these forces causes flow.
• continuous operation
33
Cluster
• Part of the machine which is
attached to the cow
• Claw piece and four teat
cups
• Connected to the bucket,
milk cup or recorder jar via a
milk tube
• Can be removed
automatically
34
Herringbone Parlours
• Cows stand in echelon
formation at 30°–35° to
the operator's pit with no
division between cows.
• Distance between udders
is reduced to 0.9 m.
• Operator has control over
cow entry/exit
• Cows enter and leave in
batches. Suitable for
herds of 50–400 cows
35
Side by Side
• Modification of the
herringbone.
• Cows stand at right
angles to the operator's
pit, so that 3 cows occupy
the length required for 2
in the herringbone.
• Cows must be milked
through the back legs.
36
Rotary Tandem
• Most expensive per cow
place in terms of cost and
space requirement. Cows
stand nose-to-tail in stalls
circling the operators
work area. Operator
cannot assist cow entry
but can see all cows
easily during rotation.
• 250 cows plus
37
Annual Cycle in Dairying
• Day 0 Cow calves - begins to lactate
• Lactation 305 days
• Dry period 60 days
• Ideally 365d calving interval- but more often
closer to 400 days
• As with suckler cow if to have 365d calving
interval need to conceive 80-86 days post
calving as gestation length is on average 278283 days
• Aim to serve cow 56 days post calving
38
Planning
1. Plan calving dates (includes both cows and
heifers)
• Herd with mean calving date c. Feb 15th (first
cow calving c. Jan 20th) has highest potential
profits– Higher milk yield
– Increased grass consumption and reduced silage
consumption when compared to herd calving in Aprilreduced costs
• Mean calving date in Ireland is March 16th
39
Requirements for Replacements
in Dairy herd
• 17% rate of replacements ideal
– i.e. 17 cows culled from 100 cow herd every year with
17 new heifers required
• Average replacement rate in Ireland is 27%
–
40
Replacement Heifers:
Age at Service and First Calving
• At first service heifers should weigh approx.
2/3rds of final mature weight = 400kgs
– c. 15 months
– Calving at c. 24 months
– dystocia if calving before 22 months
– Fit in with calving pattern of herd
• Choice of bull
– Usually use breed Aberdeen Angus or Hereford- less
calving problems than Friesian
– Variation within breeds- ‘Easy calving bull’
• BCS 3- 3.5 6-8 weeks pre calving
41
Diseases of Dairy (and Suckler) Cows
•
•
•
•
•
•
•
Brucellosis
Mastitis
Milk Fever
Ruminoacidosis and Ketosis
Grass staggers
Lameness - Foot Problems
Bovine Spongiform Encephalopathy
(BSE)
• Johnes Disease
42
Brucellosis
•
•
•
•
ZOONOSIS - undulant fever in humans
HIGHLY INFECTIOUS
Caused by bacterium Brucella abortis
Causes abortion –usually 5-7th month of
pregnancy
• Non-pregnant animals can act as carriers
43
Brucellosis
• All breeding cattle (cows and bulls) in Ireland
must be tested for brucellosis - blood test
– All females over 1 year
– All bulls over 2 years old
– After 30 days movement test required
• Animals that are found positive for brucellosis
are slaughtered
• Treatment of affected animals is not appropriate
44
Mastitis
• Bacterial disease of the udder
• Infection gains access to gland via
teat
1. Dirty housing conditions (pre and
post calving)
2. Poor hygiene during milking
3. Damage to teat sphincter due to
inconsistent/ excessive vacuum in
milking machine
45
Mastitis
• Only 1% of cases are noninfectious
• Bad hygiene, flies, teat lesions etc. can increase
suceptibility
• Up to 20 bacteria responsible for mastitis in
cows
• Including:
–
–
–
–
E.coli
Streptococcus
Staphlococcus
Pseudomonas
46
Mastitis
• 2 forms:
– Clinical – signs and symptoms of disease
observed- fever, visible alteration in milk etc.
– Subclinical – alteration in milk- increased cell
counts and bacteria present
• Usually chronic infections
• Eg. Staphlococcus aureus
47
Swollen, gangrenous udder of
ewe with mastitis.
Top of a strip cup showing clots and
serous milk from a cow with acute
mastitis.
Brown Swiss heifer with swollen
rear gland with mastitis
48
Mastitis: Treatment
• Clinical mastitis is treated with
intramammary antibiotics
• Milk from treated cows must be discarded/
fed to calves
– Penalties for selling milk contaminated with
antibiotics
49
Milk Fever (parturient hypocalcaemia)
• Misnomer! No fever- reduced temperature
usually!
• Metabolic disorder
– Subnormal levels of blood calcium
– Sudden production of large volumes of milk
(rich in calcium)
– Blood calcium levels fall and body stores of
calcium (in bones) cannot make up shortfall
fast enough
•
50
Milk fever cont.
• Milk fever usually seen at time of calving
up to 10 days post calving (most
commonly 24-48 hrs post calving)
• High yielding cows usually in 3rd or 4th
lactation at greatest risk
• Genetic link?
– Jerseys > friesians
51
Milk fever: Treatment
• Urgent treatment required
– Monitor recently calved cows
• Sit up to prevent bloat- prop up with bales
etc.
• Warm bedding and shelter if possible
• Inject warmed Calcium borogluconate
under skin
– Other minerals (Mg and Phosphorus) often
also deficient -combined mineral solution
usually administered
52
Milk fever: Treatment
• Staggering cows should recover in 1 to 2
hours post treatment
• Vet consulted if ‘down’ and/or no response
in 2 hours
• Remove calf/ do not milk (or only partially
milk) for at least 48 hours
53
Ruminoacidosis
• Overfeeding concentrate ration– disturb ruminal function and normal microbial flora
• Results in very high levels of lactic acid and low
pH in rumen
54
Ketosis
•
•
•
•
•
Like pregnancy toxaemia in ewe
Metabolic condition
Usually in peak lactation
Energy imbalance
High demand for glucose- appetite/ intake
cannot provide enough for high yielding
dairy cow
55
Ketosis
• Number of effects in body of this energy
imbalance
– Gluconeogenesis- production of ketone
bodies- acidic
– Breakdown of body fat reserves- fat may be
incompletely oxidised (due to low availability
of glucose) and may lead to fat deposition in
liver- fatty liver
56
Grass Staggers (‘Tetany’)
• Metabolic disorder due to subnormal
blood levels of magnesium
– Hypomagnesaemia
– Beef cattle, calves as well as both dairy
and suckler cows
57
Grass Staggers (‘Tetany’)
Predisposing conditions
• Can occur at any time of year when Mg in diet is
low
• Most common occurrence of ACUTE diseasewhen cows turned out to lush, heavily fertilized
grass
– Such grass is often deficient in Mg
• Can be aggravated by recent calving or cold
weather
• Soil type can predispose
58
Grass Staggers (‘Tetany’)
Symptoms
•
•
•
•
Nervousness
Muscle tremors
Twitching eyeballs
Muscle spasms, coma and death can rapidly
follow - i.e. an emergency
• Sudden death
59
Grass Staggers (‘Tetany’)
Prevention and treatment
• Prevention:
– Calcined magnesite (MgO) can be added to
diet (60g /head /day) 2-3 weeks before
turnout on lush pastures
– Continue to feed or a period after turnout
• Treatment
– Prompt Vet attention- intravenous magnesium
60
Lameness
• Common problem
• Wear and tear
– Long periods on slats
– Poor roadways for dairy cows (sharp stones,
uneven surfaces etc.)
– Poor conformation
• Bacterial infections can occur
61
Bovine Spongiform Encephalopathy
(Mad Cow Disease)
Neurodegenerative Disease of cattle
• Transmissible spongiform encephalopathy
• Infectious agent is a prion protein
• Causes spongy degeneration of brain
• Symptoms:
• Nervous symptoms in affected cattle- inability to stand and
dementia
Control measures in Ireland and EU
• Notifiable
• Slaughter policy Nervous tissue from spinal cord removed
from carcase
• All animals over 30 months slaughtered must be tested
• All casualty animals over 24 months must be tested
62
Other Transmissible Spongiform Diseases
• Similar disease in sheep- Scrapie
– Fatal, non curable disease of sheep first
noted in 18th century
– Nervous symptoms
– Itching, lip smacking and hopping gait (see
video clip), progressive ill thrift and wasting
– Breeding programme using sheep with
genetic resistance to this disease- sheep
blood sampled
• Consumption of infected meat products
assoc. with development of variant
Creutzfeldt-Jakob Disease (vCJD) in
humans– different to ‘classical’ CJD
– 165 humans have died to date in UK as a
result of vCJD
Sheep with scrapie
may scrape hindend
and nibble at fleece.
Upper image shows
sheep with nervous
symptoms and wasting
63
Dairy farm cleaning operations
• Milk of low bacterial count (20,000/ ml) requires a
relatively consistent high standard of hygiene.
• Good keeping quality to store on farm at 4C for 3 days.
• Contamination from improperly cleaned equipment can
raise the bacterial count to more than 100,000 per ml of
milk immediately after milking.
• Inferior keeping quality.
• Levels of cleanliness depend on :
–
–
–
–
Type of cleaning product
Water quality
Method of cleaning
Equipment to be cleaned
64
• Detergents are necessary to clean milking and
ancillary equipment effectively before disinfection.
Effectiveness is increased with solution temperature,
concentration and time of application.
Bulk tank iodofor detergent
65
Detergents
• Increase the 'wetting' potential over the
surfaces to be cleaned,
• Displace milk deposits,
• Dissolve milk protein,
• Emulsify the fat
• Aid the removal of dirt.
66