Farm Repro and Neonatal Flashcards
What are congenital issues?
What is the aetiology?
What are some examples?
Abnormalities in structure and function at birth
Aetiology- genetic or environment
Examples-
CV- PDA, VSD
Urogenital- patent urachus
Musculoskeletal- contracted tendons, dwarfism
Neurological
Dystocia is commonly due to neonates being oversized
What outcomes does this cause?
What are the consequences?
Oedema, bruising, fractures
Hypoxia-
compression of umbilical cord, premature placental separation
Acidosis-
metabolic- lactic acid due to tissue hypoxia, respiratory- poor lung function
Consequences- failure to nurse and reduced passive transfer
How long should it take a calf to be in sternal recumbency?
What can be used for the diagnosis of problems in newborn calve?
should be less then 5 minutes- if over 9 increases chance of death
Diagnosis- thermometer, stethoscope, blood gasses (less so)
What are the ABCs of resuscitation?
What are the other techniques?
Airways-
intubate, laryngoscope, sternal recumbency, pull the tongue out, pass tube
Breathing-
ambubag, blow down tube
Circulation-
fluids
Other techniques- cold water down the ear, rub with straw, acupuncture on philtrum, doxapram
What are common perinatal physiological problems?
Inactivity/lethargy- standing and sucking essential
Hypothermia- calfs temp drops to 39 in 30 mins, should not go lower then this
Hypoxaemia- numerous aetiologies
Hypoglycaemia
How much colostrum should be fed in the first 24 hours and why?
Minimum of 5% at each feeding (2-3l)
First feed within 2h and again 6-12 hours
=10% within 12 hours
The concentration of immunoglobulins and permeability of the calve gut decreases rapidly within the first 24 hours
What does colostrum contain?
Fat and protein- 50% more fat 4x more protein (immunoglobulin)
Vitamins and minerals-
fat-soluble vitamins A, D, and E (<8x), Vit B12 8x
Macrominerals/Micro (Ca, P, Mg)(Cu, Fe, Zn)- 2-20x more
Immune cells
Others- growth factors, enzymes, cytokines
What are the 4 Qs of colostrum intake?
Quality
Quantity
Quickly
sQueaky clean
Why do a lot of calves not have sufficient passive transfer?
High merit dairy cows have poor quality colostrum- dilution effect, calf need more
Conformation- big teats
Supervision- 34% of calves don’t suck within 6 hours
Bad calvings-
acidotic calves, do not suck enough
How should colostrum donors be selected?
- Health dams- negative for diseases (Johne’s), prolonged residence at farm
- No pre-calving milking or milk loss
- Only first milking colostrum should be given initially
- Use colostrum from one dam per calf
What affects the quality and quantity of colostrum?
How is colostrum quality monitored for?
- When the colostrum is collected- decrease in IG with time
- Breed of cow
- Parity
- Pre-partum nutrition
- Length of dry period
- Pre-milking
- Abortion/induction
- Masitis
Brix refractometer- >22%= 50g/l
Colostrometer
let cool- 20 degrees
How is colostrum pasteurised?
What are the pros and cons?
60 degrees for 60 mins
Pros-
Bacterial reduction- Mycobacterium avium subsp. paratuberculosis, Salmonella spp., Escherichia coli etc
improved efficiency of IgG absorption
Cons-
not sterilisation
kills leucocytes
Costs- labour
What should be considered when collecting colostrum for freezing?
What are the pros and cons?
Collect from first milking only
Only freeze good quality
Collect from lowest risk heifers (Johne’s)
Pros-
free, farm-specific antigens
Cons-
cost of storage
How are colostrum replacers produced?
What are the pros and cons?
Spray drying colostrum or concentrate whey from cheese
Efficacy of absorption is not as good as natural
Expensive
Less tailored to individual farms
Better then nothing!
How can failure of passive transfer be defined?
Serum IgG <10mg/ml- 55g/l
What are the common infectious diseases of neonatal ruminants?
What are the epidemiological considerations?
Diarrhoea
Joint ill
Navel ill
Septicaemia
Bloat- rumen and abomasal
Epidemiological considerations-
1) the reservoir
2) modes of transmission and agent characteristic
3) incubation period
4) Period of communicability
What cleaning should be done for prevention of infectious diseases in neonates?
- removal of organic material
- destruction of microbes follows first-order logarithmic decay
- Contact time, temperature, pH, water content/hardness,
- Smooth surfaces preferable
What can be used for diagnosis in a neonate?
- Demeanor
- Suck reflex
- TPR
- faeces
- Navel
- hydration staus
- Acid-base staus
- CNS signs
- Abdominal distension
- Abdominal signs
- chest sounds
- CSF tap
- ZST/TP
- PM
What is the route of infection of navel ill?
What can be infected?
What is a key sign?
What are the sequelae?
What are the risk factors?
Infection via navel or oro-respiratory route
May involve umbilical arteries, veins, urachus
Key sign- hard swollen navel
Sequalae- peritonitis, septicaemia, polyarthritis
Risk factors- pathogen load, patent navel, immune status of calf
How is navel ill diagnosed and treated?
Diagnosis-
clinical examination- swollen and hard, check for a hernia
Probe
Ultrasound- peritonitis, extension up the vessels
Treatment-
antibiotics
drainage
surgery- remove infected, if veins poor prognosis
What is joint ill a sequel to?
What are the risk factors?
What are the signs?
What is the prognosis?
How is it treated?
Sequel to navel ill usually
risk factors- hygiene at calving, FPT
Single or multiple joints- swollen painful
Prognosis- poor, depends on joint affected
Treatment-
reduce bacterial load
antibiotics- 2 weeks course following improvement, begin with IV
Joint lavage- useful but often hard to do
NSAIDs
Antibiotic impregnated beads- ‘home made’- methyl methacrylate, antibiotic impregnated, place in or around joint, remove in 4 weeks
What is bacteriaemia and septicaemia?
Bacteraemia-
bacteria in blood
2nd to mucosal damage- rumen acidosis, gum disease
Septicaemia-
bacteria multiplying in blood
concurrent endotoxaemia
fatal
What agents commonly cause septicaemia?
What is a prime determinant?
When is it more commonly seen?
What are the clinical signs?
How is it treated?
E.coli
Actinomyces
Staph
Salmonella
The prime determinant is the lack of colostral antibody
Usually seen from 1-5 days of age
Clinical signs-
non-specific, collapsed, shocked, very congested conjunctive, CNS sometimes
Treatment- rarely successful
antibioits, NSAIDs, corticosteroid, fluid therapy, supportive nursing
What agent causes calf diptheria?
What is the signs?
What factors increase infection
How is it treated?
Fusiformis necrophourm
Oral lesions-
sore mouth, salivation and foul smell, ulcerative lesions
Dirty buckets- poor hygiene
Tx- penicillin
What can cause abdominal swelling in young calves?
Abomasal bloat-
typically calves 1-2 weeks old
will die within 6 hours
causes?- clostridium, poorly mixed MR
L sided swelling- free gas in abomasum
R sided swelling- abomasal again
Atresi coli- gradual distension over the first few days- total absence of faces- euthanasia
How should a swollen calf be approached?
Full clinical exam
Pass stomach tube- wont resolve abomasal
If distention resolved- rumen bloat
Listen to guts before and after passing tube- pings, splashing
What can cause rumen bloat?
Rumen drinkers-
Milk goes to rumen
Failure of closure of oesophageal groove
Ferments- metabolic acidosis
risk factors- feed hygiene, worn teats
Poor rumen development- pot bellies
How is abomasal bloat and ruminal bloat treated?
Abomasal-
sedate and roll onto the back
.16 gauge needle into ‘ping’
Ruminal bloat-
relieve distension with a tube
What are the 5 major agents that cause calf scours?
Rotavirus
Coronavirus
Crytposporidia
K-99 E.coli
Salmonella
What is the mechanism of action of rotavirus and coronavirus?
How does this cause scours?
Damage to intestinal lining
Malabsorption of milk- fluid and electrolyte loss
dehydration, acidosis and death
What E.coli causes characteristic simple scours in calves?
How does it cause scours?
Therefore how can it be treated?
E.coli K-99
Attaches to the gut wall and secretes a toxin that affects the intestinal lining of cells-
the toxin causes hypersecretion of water and electrolytes- diarrhoea
Treatment-
the E.coli doesn’t infect or damage the cells, the calve dies by dehydration and acidosis
therefore early oral fluid is the key to success
What are the effects of Salmonellosis and Clostridia on the gut and peripherally?
When does peak salmonella shedding occur?
What are the signs?
How is it treated?
Salmonellosis and clostridia- damage the gut tissue locally but also severe systemic inflammation from toxin release
Peak shedding following stressors- calving
Signs- diarrhoea ± mucous casts, dysentery, pyrexia, joint infections, pneumonia
Treatment- aggressive antibiotic and antiinflammatory treatment
What are the host defences in diarrhoea of calves?
Passive immunity- local IgG and IgA adhering to mucosal surface, derived from colostrum- first and continued intake
‘medical colostrum’ then ‘tonic colostrum’
Healthy gut flora- suppressed growth of pathogens- competitive inhibiton
Health mucosa- nutrition
What affects the epidemiology of the environment?
Pthogen load- space, time
Cavling area- is it crowded
Hygiene- environment, foodstuffs and utensils
Inside v outside
Single v group housing
Cleaning protocols
What are the calf factors for scour infection?
Colostrum status-
did the calf get enough at the right time
Others-
stress
chilling
nutrition
Feeding routine-
Hygiene, temperature, composition, bucket, teat
Housing, comfort, warmth
How can scours exposure be minimised in dairy and beef?
Dairy-
- clean calving
- ‘snatch calve’ within 2-4 hours
- Clean housing
- Hygiene- at feeding
- Hostpitalise sick calves
Beef
- Calve outside- tight calving period, flow system, sandhills system
- Hospitalise sick calves
How can protection of scours be maximised in dairy and beef?
Dairy
- 5% within 2 hours, repeat 6-12 hours
- continue colostrum feeding for 4-10 days
Beef
- Adequate cow nutrition- feed for 3 weeks pre-calving
- Frozen colostrum
- Vaccinate dam
What can be the dam be vaccinated with in prevention of scours?
ETEC, rotavirus, coronavirus
Vaccinare 3- weeks before calving
Need to know calving date
Works via colostrum/milk- colostrum management
What is the purpose of the sandhill system?
Describe the sandhills system for beef cattle
Reduces-
contact between younger and older calves
Build up of pathogens
Eliminates pathogen multiplier effect
- Animals start on 1 pasture- cows that dont’t calve move onto next
- This means the calving cows have a fresh pasture
- After 2 weeks the pastures of calves can be combined
What principles of sandhills can be applied to UK?
Turn out asap
Segregate cow/calf pairs by age
7-10 days spread of calves
Can mix at 4 weeks of age
Abolishes pathogen multiplier effect
When does coccidiosis occur in calves?
What increases incidence?
What are the signs?
What are the treatment and diagnosis?
Usually older calves >21 days
Poor hygiene- especially near troughs
Dark scour ± blood- tenesmus- usually bright
Treatment- sulfonamides, vocoxan
Diagnosis- faecal oocyst count
What is necrotic enteritis?
What causes it?
What are the signs?
How does it appear PM?
Affects 2-6-month-old suckers
Usually sporadic cases
Usually fatal
Aetiology unknown
Pyrexia, pale MMs, leucopenia, thrombocytopenia
PM- necrotic lesions of gut and respiratory tract
What are the signs of peri-weaning scour syndrome?
What needs to be looked at?
PAsty scour, poor growth
-bloat, pot belly
Look at feeding, management
What is diarrhoea?
Failure of net intestinal uptake of water and sodium such that the colon is overwhelmed
What does diarrhoea lead to in a calf?
Dehydration/hypovolaemia
-pre renal failure and shock
Metabolic acidosis-
loss oh bicarbonate into gut
L-lactic acid from tissues
D-lactic acid from colonic fermentation
Hypoglycaemia- starvation
How can dehydration by estimated?
Demeanor, eyeball recession, skin tent duration, increase in total protein
With the failure of passive transfer- a dehydrated calf might show to be normal
What does Stewarts strong ion difference explain?
Explains the underlying physiology regulating acid-base balance
Na, K, Cl, Protein, Unmeasured anions (Lactate, SO4, PO4, Oxalatate, Ketocacids)
Strong ion difference (Na + K - Cl) = 35-45, decreases with acidosis
Giving NaCl solution can cause acidosis as there is less Cl relative to Na
How can acid base be diagnosed in the lab?
Blood gas machine
Harleco apparatus measures TCO2
pH meter
What kind of acidosis is this?
What shows dehydration?
What would cause a low HR?
Metabolic acidosis- low CO2
Increased PCV, urea show dehydration
Low HR from increased K+
What are the therapeutic targets for fluid therapy in a diarrhoeic calf?
Hypovolaemia
Matabolic acidosis
Hypoglycaemia
Pre-renal failure
What are the considerations of oral fluid therapy?
Can use commercial products or be homemade
Typically around 5% BW or 2l
Only use an oesophageal feeder if necessary- damaging- listeria
Don’t withhold milk replacer
Seperate fluids with milk replacer
What are the major requirements for electrolyte solutions for oral dehydration?
- Supply sufficient sodium to normalise ECF volume
- Provide stubsances- glucose, citrate, propionate that facilitate absorption of sodium and water from the intestine
- Provide an alkalinizing agent to correct metabolic acidosis, usually present in calves
- Provide energy because most calves have diarrhoea are in negative energy balance
What are the advantages of the inclusion of VFAs in electrolyte solution of bicarbonate?
- Acetate and propionate facilitate sodium and water absorption in the calf small intestine, whereas bicarbonate does not
- Acetate and propionate produce energy when metabolized
- Acetate and propionate do not alkalinize the abomasum
- Acetate do not interfere with milk clotting in calves
How should oral fluids be administered?
When- ASAP
Route- teat and bucket best
How much- 4-8 litres daily
How often- little and often
Milk as well
What are the advantages and disadvantages of oral fluid therapy?
Adv-
- Feed the calf- maintain body condition, energy for immune response
- Feeds the gut mucosa- assists in repair
- Ensures intake of Ca, Mg, vitamins
Dis-
- May worsen diarrhoea via colonic overload
- May worsen acidosis via colonic fermentation
- May discourage farmer
How do IV fluids allow correction of Na and K?
Improves plasma volume
Improving renal function- kidneys function
Improves metabolic acidosis and corrects Na and K
What are volume expanding fluids?
Volume expanding fluid- isotonic
Plasma like-
Na, BIC, K
NaCL- saline
NaHCO3
What are hypertonic solutions?
What other fluids can be used?
Sodium bicarbonate- 5%
Sodium bicarbonate 8.4%
Saline 7%
Dextrose- glucose
Colloids- uncommonly used
What should be given to dehydrated calves under and older a week?
What should be given to a dehydrated calf unable to stand?
What are the following targets for dairy calf rearing?:
Mortality
Weaning weighy
3-month weight
Service weight
Calve time
Mortality less then 5%
Weaning weight >65kg
300kg service
Calves at 24 months
To calve at 24 months
When does the cow need to be served?
What weight?
What is the calving interval as an adult?
serve at 400 days
Weigh at 400kg
Birthweight at 40kg
Grow 360kg
Calving interval 400 days
What are the constraints of calve growth?
Disease-
neonatal scours
pneumonia- post weaning
Sub-optimal nutrition
Sub-optimal environment
What is lower critical temperature and what is a calves LCT?
Lowe critical temperature is the lowest temperature that an animal can wistand before using having to increase energy expenditure
Calve 15-20 degrees depending on humidity
When should calves be weaned?
When eating 1.5kg daily for 2-3 days
When at least 8 weeks old
Weighing at least 65kg
Can either dilute or reduce volume
