Prevention and treatment of neonatal ruminant disease

what physiological changes must take place within minutes of birth?

• lungs inflate

• foreamen ovale closure

• ductus arteriosus closure (connects pulmonary artery to aorta in utero)

• urachus closure

• start generating body heat

what are common perinatal physiological problems?

• hyperglycaemia

• inactivity / lethargy

• hypothermia

• hypoxaemia

• acidosis

what is dystocia most commonly caused by?

• foeto-maternal disproportion

  • narrow pelvis of mother

  • oversized calf

• maldisposition

what does dystocia cause?

• acidosis and hypoxaemia

• failure to nurse and reduced antibody absorption —> failure of passive transfer

how can we resuscitate new borns?

• airway

  • intubate

  • sternal recumbency - pull tongue out and pass tube

• breathing

  • ambubag

  • blow down tube

• circulation

  • fluid

• other methods:

  • cold water down ear

  • rub with straw

  • put straw into nose

  • gently swing

  • acupuncture point on philtrum

what does colostrum contain?

• fat and protein

  • 50% more fat than normal milk

  • 4x more protein than normal milk

• vitamins and minerals

  • 8x more vitamins than normal milk

  • 2-20x more minerals than normal milk

• immune cells

• growth factor

• enzymes

• cytokines

what factors affect colostrum quality and quantity?

• quality - time from collecting colostrum

• cleanliness of what your collecting colostrum in

• pre-partum nutriton

• breed of cow - diary vs beef

• mastitis

how can we check quality of colostrum?

• Brix refractometer

  • want 22% or higher

• colostrometer / hydrometer

how much colostrum should we feed and when?

• feed 10% of body weight within 2 hours of birth

• and then 5-10% of body weight within 6 to 12 hours

how can we reduce risk of GI infection in neonates?

feeding ‘transition milk’ (colostrum of lower quality) for 5-7 days

when are calves usually weaned?

8-12 weeks

• this can be stressful time for calf —> increased pneumonia risk

how can we ensure colostrum is clean and hygienic?

• clean and disinfect teats

• clean and disinfect collection buckets

• can pasteurize

how should we store colostrum?

• at 4^o C in fridge (< 1 week) or freeze

• if frozen - thaw gently

how can we pasteurise colostrum?

60^oC for 60 mins

what are pros and cons of pasteurisation?

Pros

• bacterial reduction

• improved efficiency of IgG absorption (~3%)

cons

• doesn’t sterilise

• heat treatment kills some leukocytes

• cost, labour and maintenance

• takes too long to pasteurise colostrum from cow and provide to her calf - need to have colostrum already collected from another cow, and pasteurised ready for next calf being born

how should we freeze colostrum?

• only freeze colostrum from first milking - needs to be good quality

• freeze in milk containers

• collect from animals at lowest risk of Johne’s disease - heifers, or test cows

what are cons of colostrum replacers and supplements?

• efficacy of absorption less than natural colostrum

• expensive

• less tailored to individual farm

• can be difficult to determine Ig content

what is failure of passive transfer?

serum IgG < 10mg/ml - serum TP < 55 g/L

• due to failure of IgG production, insufficient feeding or failure to absorb adequate colostral antibodies

• mechanism of absorption ends by 24 hours of age

• major risk factor for all calf disease

how can we assess passive transfer?

• from day 2-7 post-calving

• measure serum immunoglobulin

  • refractometer - TP should be > 55 g/L

what are the most common neonatal infectious diseases of ruminants?

• diarrhoea

• navel ill

• joint ill

• septicaemia

• congenital abnormalities

• bloat (abomasum and rumen)

how should we clean to break the cycle of neonatal infectious diseases?

• remove organic material e.g. straw

• chemical disinfectant - contact time, concentration, temperature, pH, water content, water hardness and amount of organic material present all key to determine success of disinfection

• smooth surfaces preferable to reduce organic build up

what are key aspects of the neonatal examination?

• demeanor

• suck reflex

• temperature, pulse, respiration

• faeces

• naval

• hydration status

• acid-base status

• CNS signs

• abdominal distention - left, right or both

• abdominal sounds

• heart and lung sounds

what is navel ill?

• infection via navel or oro-respiratory route

• may involve umbilical arteries, veins and urachus

what is the main clinical sign of navel ill?

hard, swollen navel

may also have hernia

what can navel ill cause?

• peritonitis

• septicaemia

• polyarthritis - joint ill

what are risk factors for navel ill?

• pathogen load - hygiene at calving

• patent navel - is navel dressed? - use strong iodine

• immune status of calf - colostrum intake

how do we diagnose navel ill?

• clinical examination - swollen and hard, check for hernia

• probe

• ultrasound

  • peritonitis

  • extension up vessels

how do we treat navel ill?

• antibiotics

• drainage

• surgery

  • remove infected umbilical arteries and urachus

  • if veins affected - poor prognosis

what is joint-ill?

(= septic arthritis)

• sequel to navel ill

• may affect single or multiple joint

what are clinical signs of joint-ill?

swollen and painful joints

what is the prognosis of joint-ill?

poor - depends on anatomy of joint affected

how can we treat joint ill?

• antibiotics - 2+ week course, start early, begin with IV

  • use Oxytet or penicillin

• joint lavage - useful but often hard to do

• anti-inflammatory drugs

what is bacteraemia?

• bacteria in blood

• secondary to mucosal damage

  • e.g. rumen acidosis, mastitis, gum disease

what is septicaemia?

• bacteria multiplying in blood

• concurrent endotoxaemia

• fatal

what is the prime factor causing septicaemia in neonates?

lack of colostral antibody

what age neonates do we see septicaemia?

• most cases - 0-5 days

  • associated with failure of passive transfer

• few cases >5-14 days

  • associated with decline in IgM

what are clinical signs of septicaemia?

• meningitis

• collapsed

• shock

• very congested conjunctiva - petechiae

• may have CNS signs

how can we treat septicaemia?

note - rarely successful

• antibiotics

• NSAIDs - flunixin

• corticosteroids

• fluid therapy

• supportive nursing, warmth, feeding

what congenital defects do we see in calves?

• cardiac - patent ductus arteriosus, ventricular septal defect

• atresia ani and atresia coli

• cleft palate

• contracted tendons

• cataracts - BVD (bovine viral diarrhoea)

• cerebellar hypoplasia - BVD (bovine viral diarrhoea)

what causes calf diptheria?

fusiformis necrophorum

what are clinical signs of calf diphtheria?

• sore mouth

• salivation and foul smell

• ulcerative lesions

what can cause calf diphtheria?

poor hygiene - dirty buckets

how do we treat calf diphtheria?

peniciliin

what types of abdominal swelling do we see in young calves?

• abomasal bloat - often left side, but may also be bloated on right side

• abdominal catastrophe e.g. volvulus, torsion - often right sides swelling

• atresia coli - gradual distension over first few days and complete absence of faeces

what are causes of abomasal bloat?

• rapid fermentation of carbohydrates

• clostridium

• poorly mixed milk replacer

• too much or too concentrated milk replacer

what age calves are usually affected by abomasal bloat?

1-2 weeks old

what is indicated in right sided swelling if we suspect volvulus or torsion?

laparotomy

what would we do if calf has atresia coli?

euthanasia

how would we approach bloated calf?

• full clinical exam

• can try to pass stomach tube - but won’t resolve abomasal bloat

• listen to guts before and after passing tube

  • pings

  • splashing

how do we treat calf abomasal bloat?

• sedate

• roll onto back

• use needle to deflate where ping sound can be heard

  • place stethoscope over abomasum area and flick stethoscope —> ping sound

how do we treat calf ruminal bloat?

• relieve distension with tube

• if repeated - use trochar/fistula

  • punch into rumen through body wall, screw in and remove sharp bit