Cows Flashcards
What is low magnesium also known as?
staggers
grass tetany
peracute low magnesium signs?
hyperaesthesia eat twitching sensitive to sound staggers and collapse jaw champing sudden death high HR
sub acute low mg signs?
slow onset spasmodic urination and defecation muscle tremor staggering gait high HR
chronic low mg signs?
poor appetite
low yield
more vocal
high HR
low mg treatment
bottle of Ca borogluconate with Mg hypophosphate slowly by IV
Mg sulphate 25% subQ
hypoMg prevention
Mg O in conc
Mg oral bolus
Mg in water
hypo Ca other names?
bovine parturient paresis
acute flaccid paralysis
milk fever
How is Ca homeostasis
absorption from GIT, kidney, bone is PTH present
active vit D
Mg needed as a co-factor
normal blood ca = 2.3 - 3.2
hypo Ca subclinical
hypersensitive excitable tremors ear twitching ataxia bloat / gas
blood ca 1.8 - 2.3
moderate hypo Ca
sternal recumbency depressed dry muzzle cold extremeties bloat / gas no defecation delayed / absent pupil response
blood ca = 1.2 - 1.8
severe hypo ca
reduced consciousness lateral recumbency unresponsive to stimuli muscle flaccidity reduced CO bloat death
blood ca = less than 1.2
treatment of hypo ca
- 20% Ca borogluconate - slow IV
- sub Q Ca to prevent recurrence
monitor HR
pass dung , eructate and sit up = good
cause of hypo Ca
decreased feed intake
old cows cant access bone
channel breed
altered kidney absorption
prevention of hypo Ca
low Ca in dry cow and high in lactating
Mg supply
DCAB
drench / bolus high risk cows
hypo P
happy downer cow
from high ca in food so low PTH so low P
give foston IV
what is DCAB?
dietary cation / anion balance
monitor urine ph
what are the 2 cations and anions in DCAB?
cations = Na , K anions = Cl, S
what is the aim of DCAB?
give excess anions to induce metabolic acidosis to make PTH receptors more effective
how DCAB?
low K
high anions
what are the two ways that feed intake is controlled?
distension feedback - mechanical receptors
chemostatic feedback - chemical receptors to the brain and then depress hunger
what can increase voluntary feed intake?
smaller particle food size
what has no effect on voluntary feed intake?
water drunk with dry food
what can decrease voluntary feed intake?
high body fat
pregnancy
inert fill
diet NDF (neutral detergent fiber - cell walls)
water in plant material (slows food passage)
4 theories for post digestive feedback?
- glucostatic theory ( high glucose suppresses hunger but doesnt work in cows as glucose kept constant)
- hepatic oxidation theory (ATP(from FA and ketones) in the liver determines vagal stimulation and therefore hunger)
- thermostatic theory ( not for ruminants as have exothermic rumens)
- lipostatic theory (leptin from adipose tissue -ve to hypothalamus to modulate feed intake, but cows always in NEB so low leptin)
cow DMI?
dmi = 2.5 % BW + 10% milk yield (kg)
cow maintenance
about 65MJ + 5MJ / L of milk
energy density of diet needed
maintenance / DMI
anti-nutritional factors? (5) that decrease DMI
- Tannins ( decrease rumen fermentation)
- protease inhibitors (poor food utilisation, legume, cereal)
- lectins / humagglutinins (poor food utilisation , legume, lentils)
- glucosinolate (effect thyroid , cabbage, oilseed rape)
- saponins (inhibit fat digestion, soybeans, peanuts, sugar beet)
What is the difference in energy between the cell contents and cell wall?
cell contents - easily digestible and rapidly available (sugar, starch, protein)
cell wall - hard to digest and slowly available (fiber)
what is NDF / ADF?
NDF - all of cell wall
ADF - lignin and cellulose, what is left after boiling in acid.
energy of forage is inversely proportional to ADF
what is PICA?
persistent licking, chewing or eating of inanimate objects
Herd vs sporadic PICA?
herd - parasite, obesity, mineral deficient, under nutrition
more likely if outdoor
sporadic - brain disorder, toxicity, metabolic disease
slurry / urine drinking?
housed herd over winter
could spread disease
boredom
what is the cow comfort index?
how many cows lying down one hour before milking - want 85%
important trough space factors
about 60 cm / cow
rough edges? cleaned out?
water factors
enough space for a group to drink
flow rate? clean? dissolved solids?
milk fat ideal and what affects it?
want = 4.2 %
depends on fibre level
conc: forage > 60:40 then lower fat
milk protein ideal ?
3.4%
affected by energy intake
5 point dung scoring
1) loose and watery
2) custard, splatters far
3) ideal - slow hard clap, doesnt stick to boot
4) thick and heavy, forms stack, sticks to boot
5) stiff, boot leaves impression
metabolic profiling - what /when
planned regular (4 x /year) after any major diet change (after 2w) cows from each group
