energy balance and herd heath

function of the rumen

1. primary or mixing, starts in reticulum- dorsal and ventral sac

2. secondary/eructation, rumen only, gas is methane, co2, nitrogen, 1L per min

3. bolus of food passes up oesophagus for remastication, chewing the cud. saliva production 100-150litres per day. 3.5kg bicarbonate per day

free gas bloat

• how much gas

• cause

• 1 litre per min gas produced in rumen

• anything preventing eructation of gas passing from cardia into oesophagus will rapidly case free gas bloat to occur

• recumbent cow/ lateral recumbency- fluid blocks cardia, no eructation

how to treat a recumbent cow

• sit cow up into sternal recumbency

• get it to stand up

• starts to eructate and bloat will improve rapidly

other causes

• physical obstruction- choke

• actinomyces bovis- also causes lumpy jaw

• lack of motility in rumen/ reticulum - tetaus, hypocalcaemia, rumen acidosis, damage to vagus nerve

frothy bloat

• gas forms a stable foa,

• small gas bubbles cannot oalesce

• eructation cannot take place

pasture bloat

leguminous bloat

• soluble protein in some forages cause foaming

• lush pastures

• clovers

grain overload/ feedlot bloat

• high level grain diets

• also associated with rumen acidosis

• finely ground grains more likely

• also can cause free gas bloat

bloat impacts

• in mild/ mdoerate bloat distension left paralumbar fossa

• severe- whole abdomen may be distended

• compression of lungs and heart

• resp distress

• death

bloat treatment

• free gas- release gas with stomach tube

• pass trochar and cannula into rumen via left sublumbar/paralumbar fossa

types of trocar and cannula

frothy treatment

• stomach tube or trochar and cannula unsuccesful

• very small amount of froth is released only and rumen distension is not relieved at all

• need anti foaming agent

• reduce surface tension

• allow gas bubbles to coalesce

• can then be eructated

• synthetic surfactnats, poloxalene (bloat guard), simethicone (birp)

• oils

• liquid paraffin/mineral oil

• cooking oil

prevention

• pasture management

• do not deed finely ground cereals

• at elast 40 percent forage

conditions of abomasum

• left displaced abomasum

• right displaced abpmasum

• torsion right side

lda/rda

• decreased feed intake

• energy deficiency

• ketone levels in blood rise

• ketosis

ketosis diagnosis

high levels of ketone bodies in urine/blood

beta hydroxybutyrate

secondary ketosis

any illness that causes the cow to be unwell and reduce feed intake can lead to ketosis eg

• LDA RDA

• metritis

• mastitis

• traumatic reticulis/hardware disease

primary ketosis

• no underlying disease

• insufficient energy intake to meet energy demand

• negative energy balance and excessive breakdown of fat/weight loss (loss of BCS)

• esp high yielding cows early lactation

fatty liver

excessive weight loss

excessive fat gets deposited in liver

fat cow syndrome- very sick

other ketosis

pregnancy toxaemia in sheep and beef cattle

liver normal cow

liver form fatty liver cow