Gen Knowledge Flashcards
Individual cut offs FPT
Lombard et al 2020
Excellent = >25g/l
Good = 18-24.9
Fair = 10-17.9
Poor = <10
Herd level FPT thresholds
Lombard et al 2020
Excellent = >40% calves =>25g/L
Good = ~30%
Fair = ~20%
Poor = <10%
IgG levels colostrum and brix%
Buczinkski 2016
IgG>50g/L
Brix% good = > 22%
Poor = <18%
Pastuerisation
60C for 60min
Delaying colostrum intake
Fischer et al 2018
Decreased passive transfer
Decreased prevalence of beneficial bacteria (Bifidobacterium and lactobacillus spp)
What else is in colostrum
Maternal leucocytes = Calf immunity
microRNAs = immune system development (van hese 2021)
Growth factors - IGF insulin = mucosal growth and nutrient absorption stimulations
Oligosaccharides = decrease pathogen adhesion
Extended colostrum feeding benefits
Health - reduction of clinical score for diarrhoea. no effect BRD (local effect of IgG)
Growth - Higher ADG (additional nutrients, feed efficiency)
Environmental stress factors affect…
ME requirements increase **not CP requirements
Thermoneutral zone = 15-25C if calf is <21d
Calf +27%/+53%/+85% of ME at 10C/0C/-10C
Heat - +20-30% ME
High osmolality of milk replacer (up to 600mOsm/kg)
Milk should be ~300mOSM/kg
Decreased rate of abomasal emptying and absorption defects
Risk of bloat and or osmotic diarrhoea
- mixing errors
Milk feeding alongside ORS during diarrhoea?
Payne and brennan 2020
Might help recover faster when compared to ORS alone
Weak evidence only
How to increase energy supply in complete milk replacer?
Increase lactose/replace lactose with glucose?
-Inc osmolality = osmotic d+
-No effect on growth
== adverse effects on calf health
Exchange lactose for inc fat
- High fat CMR - some weak evidence good for BRD. No effect on growth or feed intake
== good alternative
EU regulation
Calf water supply
ALL calves >2 weeks must have access to water or be able to satisfy their fluid intakes with other liquids. In hot weathers/sicks calves fresh drinking water must always be available
Feed conversion efficiency
Pre weaning = 55%
Weaning on conc intake!! - could be doing 2kg/day for no growth check post weaning (min 1.1-1.2kg) Aim of growth rate post weaning is 1.2kg/day as most efficient
Mycoplasma bovis - what AB are they resistant to and why?
Beta lactams - as no cell wall
M bovis - main clinical signs
List in order of frequency
- Pneumonia
- Arthritis
- Mastitis
- Otitis media
- Keratoconjunctivitis
- repro…
Sources of infection of m bovis - cow-cow and prevention
Milking parlour - hygeine between cows at milking
Milking mastitic cows last
Seperate group of positive animals
Semen can be a carrier - AB in extenders doesnt kill m bovis
Sources of infection of m bovis - cow-calf
Prevention methods
Milk feeding>colostrum feeding
-Pasteurisation 65C for 2min
-acidification pH>6 not effective
- minimise sharing equipment
- Disinfection
Sorting sexed semen - what is the % difference in DNA X and Y?
4% difference
X > Y
Why can you get a higher net return from sexed semen use?
- Less dystocia
- less post partum dz
- Milk yeild higher (because of above)
- Calf more valuable
FPT Thresholds (Lombard et al)
Serum IgG >25 g/l
TP>6.2 g/dL
Brix >9.4%
Live vaccines
Replicate as per disease
Can cause “disease like” symptoms
Create immune memory
Req less doses
Mutations possible
Inactived/killed vaccine
More frequent booster
No return to virulence
Adjuvants added
Tissue reactions possible
Less disease side effects
Marker vaccine - IBR
IgE gene deleted vaccine
If looking for wild type infection look for IgE
Live and inactivated versions available
Leptospirosis vaccination effect on shedding
Single vaccination prior to challenge can reduce shedding by 80-94%
Efficacy of vacc reduced by infection
Efficacy reduced in multivalent vaccines
Bovine respiratory disease vaccination efficacy improved by
- Administering several weeks prior to challenge
- Animals free of acute infection
- Animals in a state of immunological homeostasis
When pre calving do you get the highest ab levels when giving rotavirus/coronavirus vaccination
9-4 weeks pre calving
BVD diagnosis of antibodies
Antibody detection ELISA = accurate, high throughput, can get inconclusive results which = “not neg”
What day is preg recognition required by
day 17/18
Otherwise PGF2a secreted
When is the LH peak
Standing oestrus
lasts for 18-20h (maybe less
12-18h later = ovulation
Metoestrus
Lasts 3-5 days
Luteal development
Corpus haemorrhagicum
Luteolysis impossible as no PGF2a receptors on CL
FSH creates follicular waves
Dioestrus
Mature CL producing progesterone
large luteal cells = granulosa cells, produce more P4 and have PGF2a receptors
small luteal cells = thecal cells, produce less P4 and have LH receptors
Dairy cattle- 2 follicular waves
beef cattle and heifers - 3 follicular waves
Luteolysis
If CL doesnt recieve IFN-tau signal = luteolysis starts with PGF2a from uterus via utero-ovarian pathway = death to large luteal cells + oxytocin release which has a positve effect on more PGF2a release from uterus
Dominant follicle characteristics
Increased follicular fluid, increase in oestradiol and inhibin = suppression of FSH
Inc responsiveness to LH and continued growth without FSH
Inc LH waves at time of DF selection
Oestrus
Average 8h duration
decreased time with increased milk production (14h 25l) (2.5h 55L)
Heifers 12-14h
Beef cows<8.5h
Post partum
follicular growth occurs during first 2 trimesters.
Late preg suppressed. When P4 and oestradiol drop at birth = resumption of cycles
DF by 7-10d PP normal cycles 15-45d dairy cows
Delayed 30-130 d PP for beef cows (LH suppression)
AI timing pedometer
12h after pedometer detected oestrus
Range of time for AI post oestrus signs
4-16h
no later than 10-12h post onset = ideal
Semen thawing time and temp
45sec at 35degrees (body temp)
Use within 10-15min
Ambient conditions and fertility
THI >70 = neg associations with fert
Bull service stats
90% pregnant/ 50 healthy cows in first 3 weeks
Repro dz spread by natural service
Trichomonas fetus
Venereal campylobacteriosis
Mycoplasma and ureaplasmae
IBR (latent carriers)
BVD (PI’s)
Risk factors for Metritis/endometritis
RFM
Trauma
Assisted calvings
NEB - affects immune system
Cyst formation
DF doesnt ovulate, LH supports DF causing persistance
Risk Factors for delayed ovarian cyclicity
Dystocia
Abnormal vaginal discharge
Concurrent dz
Severe NEB
RF for cystic ovarian disease
High milk production
Later parity
Non infectious causes of abortion
Nutritional - malnutrition/deficiencys
Toxic eg mycotoxins
Physical - trauma, pyrexia, twins
Stress
Genetic abnormalities
Infectious causes of abortion
Neospora - carriers and vertical transmission
Bacillus lichenformus
Arcanobacterium pyogenes
BVD
Salmonella
leptospirosis
IBR
Campylobacter
Lungworm diagnostics usng bulk milk tank
> 0.41 in August = higher risk of lungworm
2 consecutive samples 2 weeks apart = higher sens
Se and Sp of Baermans for lungworm
Sp = 100%
Se = can be as low as 7%
Better in first time infections
Benzimadazoles MOA
Beta tubulin inhibition = cell structure disruption and cell death
Imidazothiazole MOA
Levamazole
Nicotinic receptor agonists = spastic paralysis
Macrocyclic lactone MOA
Chloride channel agonists and some nicotinic receptor antagonists = flaccid paralysis
Anthelminic resistance in cattle in Europe
Cooperia and some ML resistance reported
Onset of immunity against endoparasites
Ostertagia = two grazing seasons
Cooperia = one grazing season
Dictyocaulus = 1-2months with repeat exposure needed
Fluke = No immunity
Fluke life cycle timings
20 week total life cycle - 8 weeks on pasture/in snail. 12 weeks in cattle
Lungworm lifecycle timeline
4 weeks total
1 week eggs- L4
3 weeks L4- adult in lungs
Roundworms life cycle time line
4 weeks =
3 weeks in cattle 1 week on pasture
***Encysted arrested development stage for ostertagia in late summer/autumn time in response to cooler ambient temp
3 steps to effective parasite control
- Grazing management
- Good nutrition
- Appropriate anthelmintic use
What drugs are effective against the encysted L4 ostertagia larvae?
Macrocyclic lactones
Benzimadazoles (variable efficacy)
What classes as “safe” pasture
- Silage aftermath
- Reseeded pasture
- Mixed/follow on grazing
EMA Antimicrobial classification
Category A antimicrobials
What are they, example
AVOID
Ab not licensed for use in animal medicine, exceptional circ for companion animal medicine
eg
mycobacterial drugs
monobactams
EMA Antimicrobial classification
Category B antimicrobials
What are they, example
RESTRICT
Critically important antimicrobials in human medicine. Can only be used after sensitivity testing
eg. 3rd and 4th gen cephalosporins, polymixins, quinalones
Enrofloxacin, polymixin B, ceftiofur
EMA Antimicrobial classification
Category C antimicrobials
What are they and examples
CAUTION
Alternatives available in human medicine. Can be used when nothing in cat D effective
eg. Aminoglycosides (neomycin), amoxicillin and clavulonic acid
EMA antimicrobial classification
Category D antimicrobials
What are they and examples
PRUDENCE
1st line treatment option, avoid unessecary and prolonged use. Group treatment restricted
eg. Penicillin, tetracyclines
Impact of route of administration of antimicrobials
Least: Local individual (udder, eye)
Parental individual (IM/IV/SC)
Oral individual (bolus)
Injectable group
Oral group water/milk
Most: Oral group feed
% dehydration in calves by eyeball recession mm
Eyeball recession (mm) x 1.6 = %
% dehydration = IV fluid therapy
- > 8% dehydration
- > 4.5mm eyeball recession
Amount of bicarb (g) req by acidotic calf
= (BW x base deficit x 0.6)/12
% bicarb solution for buffering acidotic calf
1.3% (13g in 1 litre isotonic fluids)
Amount of glucose to add to hypoglycaemic calf IV fluid
= 20ml of 50% glucose per litre IV fluids
HH vs Strong ion difference
HH = simple, descriptive. Takes into account pCO2 and HCO3 only
SID = more complex, takes into account strong ions (NA/K/CL) and non volatile anions (lactate, albumin, TP) can be used when TP abnormal.
Main causes for strong ion acidosis
Constable
d-lactate/VFA production from fermentation of glucose and lactose in rumen/hindgut (eg rumen milk drinking)
Hyponatraemia due to diarrhoeal losses
hyperkalaemia (K+ movement out of cells into blood)
Intestinal bicarbonate loss
Henderson-Hasselback equation
pH = pK(6.1) + log[salt(HCO3-)]/[acid(H2CO3)]
pH dependant on the ratio of carbonic acid to bicarb
Normally = 1:20 carbonic acid:bicarb
Amount of fluid a dehydrated calf requires (L)
= BW(kg) x % dehydration
Recycled Manure solids (RMS)
- Not allowed under EU reg (cat 2 byproduct)
- UK has own reg
- Cattle on own farm
- > 34%DM
- Cattle >12m
- Cuilces only
-Milk must be pasteurised
Cows must not be on AB/DCT/quarantine
How long can Strep Uberis survive on straw bedding?
Sherwin
35days + (lab conditions)
Strep Uberis survival on sawdust?
Sherwin
<7 days
Key risk factor for increased CM and SCC from bedding?
Moisture content
Staph aureus control mechanisms
- Decrease new infections (milking time - hygeine, gloves, pre and post dipping))
- Reduce resevoir of disease (strategic treatment and culling)
Difference between Strep agalactae and Staph aureus
S. Alg = obligate intramammary palthogen
S Aur = can be found on skin, nose vulva and environment
Reliable indicators for SCC
- Annual milking machine checks
- Milking order (strip dip dry apply)
- Gloves
- Auto cluster removal
- Post milk teat disinfectant
% acceptable for liner slip
Less than 5-10/100 cows milked
What age animal has the better cure rates for staph aureus?
Young animals (60%)
Older animals (can be 1%)
Milking order for staph aureus control
Healthy uninfected cows> unknown status cows> elevated SCC cows> Chronic contagious infected cows
Serratia - method to improve control
Change to Iodine dip (can survive in chlorhex)
plus cull and segrgate inf
Mycoplasma bovis survival and infection
- No cell wall = Beta lactam resistant
- Adhere = lipoproteins
- Internalise= Hide from immune system (lymphocytes)
- Immunomodulate = inhibits lymphocyte proliferation
- Colonise
General risk factors for mastitis
- Parity - older cows more at risk of recurrence and less chance of cure
- Hygeine - risk ratio = 1.4 for every 10% increase in cows with poor udder hygeine
- Teat lesions - higher dry period inf rate
Bedding mastitis pathogen predeliction
- Straw =Highest streptococcal counts
- Sawdust =Highest coliform counts
- Manure solids = Bacterial counts cfr. sawdust, aim: 35% dry matter
Staph aureus critical control points
- Milking hygeine - pre and post disinfection, timing, gloves, towels
- Segregation - milking order and housing
- Introduction of new cattle - high health status, low clinical mastitis prevalence and low bulk muilk SCC
California mastitis test Sp and Se
Detection of SCC >200,000
Sp77.7%
Se 94.5%
Displaced abomasum cows blood workup
Hypochloraemia
Hypokalaemia
Metabolic Alkalosis
Dehydrated
Azotaemic
Serum l-lactate and prognosis AV
< 2mmol/l = good sx prognosis
>5mmol/l = high probablilty of negative outcome
Other drugs to give at DA sx
Erythromycin - 10mg/ml can help stimulate abomasal emptying
Ca
Electrolytes
Hypertonic IV fluids
Antioxidative drugs to be given before AV sx
Vit C, Vit E, dexamethasone
Contributing RF for DA development
Abomasal hypomotility
Concurrent disease
Decreased rumen fill (Could be 2ndary)
Periparturient abdominal organ placement
Genetic predisposition (deep chest)
H somni properties
- Commnesal of mucus membranes - nares, vagina and prepuce = MAIN SOURCE OF INFECTION
- Recently weaned calves = most at risk
- Septicaemia -> adherance to endothelium of vessels> contraction> platelets> thrombus > infarctions (pleural/myocardial/pericardial/synovial)
CS H Somni
Depends on organ system involved
Sudden death may be first sign of problem.
* Pleuritic histophilus = found dead without tx
* Myocardial= Exercise intolerence, collapse and death if handled/moved
* Encephalitic = depression, recumbancy, hyperaethesia > death
H somni PM findings
- Fibrinous >fibrotic pleuritis +/- bronchopleumonia
- Focal myocardial lesion (papillary muscle left ventricle) > scar tissue surrounds
- Fibrinous> fibrotic pericarditis
- Proliferative endocarditis
Primary causes of a down cow
Mt Tid
Metabolic
Traumatic
Toxic
Infectious
Degenerative
Downer cow categorisation
Primary = eg dystocia causing nerve damage
Secondary = primary cause as to why cow may be down now a secondary problem that cow cannot rise again
Alert = No signs of systemic dz, eating and drinking
Non alert= altered mentation
Ketosis diagnosis
Cow side BHB = >1.2mmol/l = ketosis (if no clinical signs= subclinical)
Salmonella invasion technique
Migrate to Lamina propria through microvilli of mucosal cells and tight junctions
Caus damage to mucosal cells = firinonecrotic plaques
Disrupts integrity of mucosal lining = leaky both ways (endotoxins in, plasma proteins out) => DIARRHOEA
Salmonella carrier status
S dublin recovered animals = TRUE carrier status. Shed for life
S Typhimurium recovered animals = passive carrier status. Shed 3-16 weeks
Salmonella - pathognomic PM finding in calves
Ulcerated bile ducts
Salmonella serovar age prediliction
S typhimurium (brought in) = calves <2mo
S dublin (endemic) = Older calves and adults
Blood transfusion calculations
Amount of blood desired = (desired % - current%) / HCT of donor x (0.08 x calf weight)
Blood transfusion for FPT
20-40ml/kg whole blood
Side effects of blood transfusions:
Tachypnoea = blood given too quickly (volume overload - throacic ultrasound)
Muscle weakness = Too much citrate - binds Ca == hypocalcaemia
Anapylaxs (shock symptoms) = allergy
Bradycardia = hyperkalaemia due to haemolysis of blood cells
Anaplasmosis spp and diff
Anaplasma maginale
- found worldwide (southern europe only)
- Attacks erythrocytes
- 7-60d incubation
- CS on haemolytic anemia
- richencephalus tick
Anaplasma phagocytophilum
- zoonotic
- bigegr problem in Europe
- 5-14d incubation
- Attacks granulocytes
- CS on immunosuppression
- ixodes tick
PI form of both = resevoir of infection
CS anaplasma maginale
Fever
Haemolyic anaemia
jaundice
pale MM
decreased milk
brown urine (not haemaglobinurea)
Wt loss
depression
late abortion
death
Inc TP, total bilirubin, ALT + haemolytic anaemia
CS Anaplasma phagocytophilum
Fever
Anaemia
leukopenia
cough
immunosuppression
anorexia
dec milk
2dary inf
late abortions
still birth
Anaemia, leukopenia, thrombocytopenia, inc AST, ALT, lactate dehydrogenase, creatinine
Babesia bovis
10d=3w incubation
More severe signs than other spp
Younger calves have some resistance to developing CS
Bos indicus have breed resistance
B divergens (UK) and B major EU
Babesia CS
Acute dz from merozoites erupting from RBC = haemolysis and circulatory disturbances
Haemolytic anaemia
Icterus
Haemogobinuria
Depression
Anorexia
GI stasis
Tachycardia and dyspnea
“cerebral” babesia
PI form asymptomatic
DDx for Babesia
Bacillary haemoglobinuria = C. Novyii type D (more fatal)
Anaplasma maginale (no haemaglobinuria)
Theileriosis (LN enlargement)
Treatment for babesia
Imidocarb diproponate salt = protects for 4 weeks and can eliminate carrier animal infection
Care with contaminated blood products/mechanical contamination as a method of introduction into herd
Killed and live attenuated vaccines available
DMI for dairy cows
Lactating dairy cows: 2.5% bwt + 10% milk yeild (20-25kg)
Close up dry: 2% bwt (12-15kg)
Far off dry: 1.5% bwt (8-10kg)
Energy requirements for milk production
5MJ per litre of milk produced
Maintainance 75-80MJ (lactation and far off)
Maintainance close up dry 90-100MJ
Dietary protein requirements
16-17% CP = milking cow ration
12% CP = dry cow ration
Dutch 5 step foot trimming method
1 - Correct toe length (80mm Holsteins to a step) Stabelising claw (inner hind and outer front)
2 - match dynamic claw (outer hind, inner front)
3 - model solar ulcer site (deep and wide on dynamic claw, small on stabelising - only to prevent trapping of mud/faeces)
(1-3 = functional trim)
4 - relieve weight bearing from affected claw (with trimming and removal of horn +- applying a block)
5 - remove loose horn
(therapeutic trim)
Staw yard space requirements dry cow
1.25m2/1000 litres milk produced
THI calves
Begin monitoring 65-69%
Upper critical limit - welfare = compromised >78% THI
Significant heat stress >88% THI
THI cows
57% - Oestrus behavious affected
65% - Conception rates affected
68% - Milk yields and quality affected
70% - behavioural indicators of heat stress
Air changes per hour for calf ventilation
4 or more changes of air per hour
LCT calves <2weeks
10-15C
Wind speed
<0.5m/s
Energy loss will double at
wind speeds of 6.8m/s
Inlet : outlet ventilated sheds
The inlet area, ideally split evenly across the two sidewalls, should be a minimum of twice the outlet area, and ideally four times the outlet area
Digi derm score M0
Clean healthy foot, no signs of DD infection
Digi derm score M1
Early stage of DD; a small, focal active, red-grey, circumscribed lesion less than 2 cm in diameter located in the skin of the interdigital cleft
Digi derm score M2
Acute, bright red or red-gray ulcerative lesion a minimum of 2 cm in diameter and commonly observed on the skin of the plantar or dorsal interdigital cleft, along the coronary band, as well as around the dew claws and on interdigital hyperplasia. The M2 lesions are commonly sensitive to the touch, eliciting signs of pain and discomfort in affected cattle upon pressure applied to the wound. M2 lesions exude a typical DD-associated pungent odour.
Digi derm score M3
Healing painless lesion, can be covered with a grey/black scab
Digi derm score M4
Chronic hairy wart like lesion, non painful hyper/dys keratinisation. Well circumscribed
Digi derm score M4.1
Chronic M4 lesion with new active lesion growing around edges
Scoring and cycle of DD
Which are the active lesions of DD
M1, M2 and M 4.1
Sensitivity
Prop true pos identified correctly
number of test pos (true test pos) / number that have disease
Specificity
Prop of true neg identified
Test neg (true test neg) / Number of disease free animals
Predictive value
PPV= prop of animals with pos test that are diseased
NPV = prop of animals with a neg test that are disease free
Dependant on disease prevalence in population
Full DCAB
-100-200 mEQ/kg DM
Anionic salts (MgCl/NH4CL)
Full TMR
Forage analysis for minerals
Urine pH monitoring (5.8-6.5) acidification
Partial DCAB
+50-(-50) mEQ/kg DM
Makes use of low DCAB forages eg grains, wholecrop, 2nd/3rd cut silage, non fertilised pastures, concentrates
Plus some anionic salts - need MgCl whatever the ration
More palatable
Harder to monitor (urine pH variable and not as consistant to monitor)
Low Ca diet pre calving
Aim for <20g/day? (at least <50g/cow/day)
Calcium binders eg zeolite - bind Ca to prevent GI absorption
Hard to do without binders as most forages are high in Ca
Primes body mobilisation of Ca
Calcium homeostasis
PTH, Vit D3, Calcitonin
PTH and vit D - elevate calcium levels - mobilise body stores, increase GI absorption and decrease renal excretion
Calcitonin lowers through increased renal excretion
Magnesium required for Vit D metabolism and PTH levels
Risk factors for hypocalcaemia
- Age/lactation number - >3 lactations (4yo) = inc risk - lower number of vit D receptors, inc milk yeild, less osteoclasts
- Breed - Jerseys > HF = Inc milk yeild, genetic predisposition
- Genetics/heritability
- Milk yeild
- High Ca pre calving
- Low magnesium in diet
- Lameness
- High K+ diet
Hypomagnesaemia
Lack of Mag in diet
Decreased absorption from GI tract and incraesed output (eg milk)
60-70% = skeleton bound
RF = Poor quality grass, high K+ fertilised pasture, Lush new spring grasss (high in K+), Milk in late weaned calves, D+ can exacerbate (less absorption time)
Magnesium sampling for hypomag
- Plasma = decfreased is not always associated with clinical signs
- CSF = good diagnostic indicator
- Urine = sensitive but no use PM
- Aqueous humour = Diagnostic up to 24h post death
- Vitreous humour = Good for chronic dx and up to 48h post death
- Calf bone = excellent for Ca:Mg ratio >70:1, Impractical generally
Bull scrotal curcumference
- > 24m = >34cm
- 15-18m = 31cm
Benefits of AI vs NS
Decreased risk of venereal dz transmission
Genetic potenital gains
Use bulls wouldnt otherwise be able to use
Campylobacter fetus (venerealis)
Inhabits the genital tract only
Transmission Bull>Cow>Bull
Natural mating = MAJOR risk
Bulls = asymptomatic with normal semen
Cows = Endomet, salpngitis, EED, abortion.
Farm = Low CR, infertility, increased calving season
Females clear ~90d
Males - treatment not recommended (streptomycin Im and sheath) infection in older bulls lasts longer
Dx = sheath wash PCR
Vaginal swab 12 affected cows/heifers - harder to detect
Trichomonas
Obligate repro tract inf
Cow = cervical inflam, vaginitis, endomet, Abortion/EED 50-70d = +++risk
Bull= asymptomatic with normal semen
Farm = very similar to campy
Over 3 yo more common
Cows clear infection in ~150d
Bulls lifelong carriers = cull
Dx = sheath wash PCR
Targets - Heat detection rate and
21 day submission rate
.>70%
% served between 18-24d
.>70%
Services per conception
1.5-2.1 service/conception
~~~
```<10% with >
3 inseminations
How to calc and target Preg rate
Submission rate x conception rate
= >35%
Failure to conceive/culling rate
<6-7%
200d NIC rate
<6-10%
Transition disease targets
- Abortion 6-8%
- Dystocia <10%
- RFM <10%
- Metritis <10%
- Endometritis <10%
- Follicular cysts <10%
Standard Holstein recommended toe length
80mm (to a step)
Measure and cut stabilising claw to appropriate length.
In the hind foot the stabilising claw is the inside (medial) claw.
In the front foot the stabilising claw is the outside (lateral) claw.
Toe angle recommended
50 degrees (48-52)
Sole thickness
6mm (6-7)
5 step dutch foot trimming method
1 - Measure stabelising claw (inner hind) (outer front)
2 - Match dynamic claw toe length
3 - Model out solar ulcer site (small dish on stabelising claw, wide and deep on dynamic)
——–
4 - relieve weight from affected claw
5 - remove underrun sole/horn at heel
***Preserve toe triangle, wall horn and heel height where possible
Use hoof testers
Hoof blocks
Foot should be reassessed after 2 weeks
Block should be taken off after 6-8 weeks to check claw isnt becoming affected by increased weight bearing
Mites distribution pattern
Sacoptes - head neck and tail head
Chorioptes - legs, udder/testes/tailhead
Psoroptes - shoulders back and tail head
Anaplasmosis
Phagocytophilum - neitrophils, CS 2ndary to immunosuppressio, zoonotic
Marginales - erythrocytes, Haemolytic anaemia
Oxytet treatment/chlortet in feed
Tick control
Babesiosis
Divergens (Uk andNW europe)
Bovis and bigema
Ixodes ricinis tick
Intraerythrocyte
Imidocarb dipropionate treatment (4week protection and eliminate carrier at higher dose)
Calves = immune (MDA and age thing)
Carrier state for years post recovery then immunity
Intravascular haemolysis
Tick control (animal level - environment not recommended)
DDx for haematuria
Babesiosis
Anaplasma marginale
Epizootic haematuria
Bacillary haematuria
SMCO toxicity
Copper toxicity
Trauma post calving
Leptosprirosis
Brucellosis
UK Brucellosis free, abortion enquires and milk sampling quarterly
Raw milk = risk to humans + abortive material and urine
Males - orchitis and seminal vesiculitis
Cattle to cattle = indirect transmission
No treatment = cull
Neosporosis
Definitive host = Canid
Intermediate host = Cattle
Calves can be born with latent infection and be persistantly infected and recrudecse at calving. Or abortions can occur
Vertical transmission between cows not horizontal
DOG POO = source of oocysts into environment = exogenous transmission dog eating infected carcass/placenta
Cost of disease = repro peformance and decreased milk production
Lifetime infection - test and cull familys
Serology PCR can be done on foetus, dog and dam
Embryo transfer only way to retain genetics if valuable line
Secure feed bins and elevate water supply
Blood transfusion indications
PCV <10-12%
<10 = definitely
11-12% discretion
+ showing signs of Inc HR, RR, weakness
Normal PCV adult cow and normal circulating blood volume
24-43%
8% of body weight (600kg cow = 48litres blood)
How much blood can a donor cow give?
Healthy adult cow can donate 10-15ml/kg (8-10litres 600kg cow)
How much sodium citrate for anticoag?
100ml of 3.8% solution/ litre of blood
How much lith hep for anti coag?
5000 units/litre of blood
How many blood types do cows have?
13 major blood types
Blood transfusion reaction CS
Inc HR, RR
Resp distress
hiccups
violent movements
Coma/death
Urticaria/abortion = delayed signs
5ml 1% adrenaline IM treatment
Electrolyte losses in diarrheac calves
Na+
K+
Cl-
HCO3-
Oral electrolyte solution for rehydration recommendations
300 mOSm (IF FEEDING MILK OR WITH MILK)
600 mOSm if not feeding milk (for inc energy requirements)
Buffer in oral electrolyte solutions
q
Propionate or acetate
Not bicarb unless feeding milk as bicarb increases pH of abo = lowers defence to E coli
Strong ion difference
Bicarb and sodium losses
Forestomach and intestinal fermentation of glucose and lactose = d lactate and VFAs
Worse in calves >7d age
Hypertonic solution for rapid resusscitation of comatose calves
5-6ml/kg over 5-6 min of 7.2% NaCl
or
6ml/kg over 6 min of 8.4% NaHCO3
SMCO toxicity
SMCO (S-methyl cysteine sulphoxide) found in Rape and Kale plants
Causes redwater, anaemia, weakness
Have to have been on crop for >1week for CS
Levels highest in older/flowering crop. Silaging doesnt reduce amount.
Can feed at no more than 50-60% diet over 10 days transition and might need to be lower and not hungry when put on
The 3 S’s for pain management
Suppress - removal of any source of pain that has no welfare benefit to animal eg tail docking
Substitute - changing proceedures for less painful ones eg disbudding better than dehorning
Soothe - use of appropriate pain relief if painful proceedures still have to be done taking into account length of pain, amount of pain expected
Magnesium requirements
5g per cow per day when lactating
= average 20% absorption therefore need 30g in diet for 5g absorption
DMI, season, fertiliser, ERDP levels, soil levels, genetics, fats can all limit uptake/availability or absorption of Mg
Biochemical findings of LDA
Metabolic alkalosis
Hypochlorameia - HCl secreton into abo but cant get out - rumen reflux
Hypokalaemia - decreased intakes of K+ feed and sequestration into abo
Decreased HCO3- being drawn into small intestine = Increased HCO3- in blood = alkalosis
RF for Leptospriosis introduction
- Open herds
- Sharing/hiring bulls
- Co grazing with sheep
- Shared/common water sources
BoHV- 1
IBR
Infectious pustular vulvovaginitis
* 8-18m = most common age group affected
* Latency = trigeminal and sciatic nerve
* Resp/repro organs and eyes
*
* Vaccine availble - gE deleted for IBR = marker
* gB = on marker and wild type virus
* gE on wild type only
BoHV-2
Ulcerative mammilitis
* Teats and udder
* blisters and scabs
* Milking routine hygeine improtant and fly control
Pseudo lumpy skin disease
* looks just like lumpy skin
* PCR to tell difference
* More mild CS
* Fever and nodules along back, faces and perineum
BoHV-4
- Generally subclinical
- Can cause repro disease = metritis, endometritis, abortion, RFM, mastitis
- Vertical and horizontal transmission
- Fomites can also be source
- Latency
BoHV-5
Bovine meningoenchephalitis and or resp disease
* Latency common
* Acute onset neuro signs including sudden death in neonatal calves
Liner slip on milking machine - target
5-10/100 cows
Milking machine phases
Pulsation ratio = Milkout - Phase A and B : Massage - Phase C and D
1:1 up to 3:1
50-60 pulsations per minute
Massage phase allows for recirculation of blood to teat
Clusters weigh ~3kg
Liner lifespan
2500 milking or 6 months (whichever comes first)
(depends on type)
Milking machine maintainance
Static tests every 6m = Plant on but not milking cows. Check vacuum pipes and motors for leaks
Dynamic tests = During milking with inline pressure sensors in the clusters at the level of the teat end
Teat end scoring system and target
N = normal
S = smooth
R = Rough
VR = Very rough
Target <20% R and VR
Penn state feed particle seperator
Good for checking:
* Assessing sorting of ration - measure at multiple times a day. Shouldnt differ in composition >3-5% from orginal TMR
* Assessing mixing in feeder wagon - over mixing = small particles, undermixing = TMR composition varies along length of feed bunk
3-4 sieves = 19mm, 8mm, 4mm and 1.18mm (not always used)
4mm = minimum physically effective fibre length