Cattle 4 Flashcards

Question

Giving parenteral fluids to scouring calves when give, why give, ways to give, examples and how to give

Answer 1

``` § If calf is unable to rise, no suckle reflex, inappetant § Isotonic vs hypertonic + oral fluid □ Hypertonic - no if severely dehydrated § IV, SC, IP □ IV most rapid followed by SC then IP □ PREFERRED when on farm is IV § Examples □ Lactated ringers solution □ Acetated ringer solution □ Isotonic sodium bicarbonate □ Hypertonic saline □ Hypertonic saline bicarbonate § How give □ Warm the fluids, gravity fed IV fluids, best to contain in small area, provide bedding, warmth and shelter □ Can hog tie the calves - tie their legs together so cannot move while occurring and pull it out □ Jugular or Auricular vein catheterisation - can glue or suture it in ```

Answer 2

``` ○ Goal § Correct dehydration - FLUID VOLUME § Correct the acidosis - BICARBONATE § Correct the electrolyte loss - Na, K, Cl, AA's § Provide an energy source GLUCOSE § Maintain cardiovascular function § Treat the causative agent ○ Max rate: 80ml/kg/hr (30-50ml/kg/hr more common) - give over 4 hours ```

Answer 3

1) Isotonic IVF with added sodium bicarbonate □ Large volume, slow delivery □ Approx. 10% calf BW over few hours (eg 4L for 40kg calf) □ Homemade recipes available 2) Hypertonic saline IV immediate followed by oral sodium bicarbonate □ 4-5ml/kg given over 4 mins □ Rapid volume resuscitating, alkalising effects slowly 3) Hypertonic saline containing sodium bicarb IV immediate followed by oral isotonic electrolytes □ 8.4% solution, 1mEq.ml bicarb □ Rapid volume resuscitation and correction of acidosis □ More expensive

Answer 4

- If calf can suckle after initial resuscitation then switch to per-oral - Urination in 30-60mins - Improvements ○ Mental status ○ Hydration status ○ Restoration of suckle reflex § If not: check for septicaemia/omphalitis/pneumonia ○ Stand within a few hours of IVFT - Can repeat the IV fluid therapy but if not responding to the second something else really wrong

Answer 5

1) antibiotics 2) anti-inflammatories § Corticosteroids - limited use in diarrhoea and calves - already secreting glucocorticoids - ALREADY STRESSED § NSAIDS - eg. Meloxicam, flunixin - some benefit - dehydrated so be careful -> if possible give fluids first 3) halocur (crytosporidium parvum) - oral drench for calves age 1-21days - good for outbreak situations 4) baycox (coccidosis) § Oral treatment and prevention of coccidiosis - prevention is best § Up to 9 months of age

Answer 6

○ Indications § Diarrhoea PLUS systemic signs including decrease suckle § Blood/mucus in faeces (bacteraemia) § Documented FPT § Bacterial disease § Viral disease- NOTHING IN AUSTRALIA AT THE MOMENT - supportive treatment only § Diarrhoea syndrome - E.coli overgrowth, 30% bacteraemic ○ Antimicrobial selection § Target E.coli in SI, bacteraemia § Gram negative activity § Septicaemia: bactericidal

Answer 7

○ Bacteriocidal compounds (esp. septicaemia - NEEDS TO KILL QUICKLY) § Third generation cephloporins (ceftiofur) § Aminoglycosides (neomycin) § Broad spectrum penicillin (amoxcillin, ampicillin) § Potentiated sulphonamides (TMPS) ○ Bacteriostatic compounds - slows the growth § Sulphonamides § Tetracyclines

Answer 8

1) E.coli (Bovilis E) § Vaccinate dams late in gestation § Transfer of anti-K99 (F5 antigen) -> block binding 2) S. Dublin and S. Typhimurium (Bovilis S) § Dams vaccinated 8 and 3 weeks pre-calving § Conflicting reports § Partial protection, but incomplete 3) Rotavirus/coronavirus (rotavec corona) § Vax neonates; modified, live, oral formulation at birth § Vax dams: modified live/inactivated - SC infection § Conflicting reports - efficacy unknown

Answer 9

``` - Mild to moderate disease ○ Oral fluids, AB's - good prognosis - Severe disease ○ Aggressive IV fluids, good nursing - can survive - Septicaemia ○ Poorer prognosis ○ Risk of polyarthritis if they survive - All cases that resolve ○ Reduced GR due to intestinal malabsorption (temp/perm) ○ Need quality nutrition ```

Answer 10

1. Triage 2. Categorise/group by severity 3. Practical treatment/management plan ○ Resuscitation, fluids -> need to development plan with farmer - give prognosis 4. Reduce further contamination 5. Reduce exposure 6. Decontaminate areas 7. CLIENT COMMUNICATION at the end of the visit

Answer 11

- Summarise in 3 points - Write instructions down (clinic handouts) - Empathise (it is more work) - Explain why/importance - Follow up phone call

Answer 12

- Viral - rotavirus or coronavirus | - Protozoal - cryptosporidium

Answer 13

- ~9% dehydrated | - 3.6 L bicarb & Hartmann’s IV - 0.09 x 40 = 3.6

Answer 14

1. Get a good history 2. Look at the environment 3. Observe the animal at rest 4. Observe urination (aka micrturition) 5. General clinical examination ○ Including urinary tract § External - vulva, escutcheon □ Crystals, bleeding, puss § Internal - kidney, ureters, bladder contents and wall 6. Blood samples - not so often ○ Blood urea nitrogen (in plasma) § Indicates renal perfusion or renal insufficiency § Limited application due to time and cost

Answer 15

``` 1) Abnormal urination ○ Stranguria (straining, painful) ○ Pollakiuria (frequent) ○ Polyuria (excessive volume) ○ Oliguria (reduced volumes) ○ Anuria (absent) 2) Abnormal appearance/contents of urine ○ Colour: from colourless to chardonnay § Normally clear ○ Clarity: clear and transparent § Normally DON'T have floaties ○ Smell: like cow's urine ○ pH: 7-9 ○ Protein/ketones/blood: nil or trace ○ Specific gravity - 1.020 - 1.050 3) Non-specific "sick cow" ```

Answer 16

- Cystitis - Pyelonephritis - Obstructive urolithiasis - Vaginitis

Answer 17

Dysuria - E.coli - Frequent urination +/- pain or discomfort - Either ascending or descending infection - Most common in females - short broad urethra - easier to ascending infection - Penicillin - to prevent secondary infection of Corynebacterium renale (loves the urine)

Answer 18

- Corynebacterium renale et al - Ascending infection (hygiene, venereal) - Haematuria, pyuria, painful microturition - Painful kidney, colic - culture - Prolonged treatment required - penicillin - Prognosis guarded

Answer 19

Dysuria - Obstruction to flow - Most common in males (esp steers) - Struvites, silicates, Ca carbonate, oxalates - Increase concentrate feeding, increase silicate pastures - Decrease water intake -> in cold areas where water freezes over - Urethrostomy or salvage slaughter ○ Salvage procedure, backwards urine - no longer breeding animal

Answer 20

- Usually secondary to calving trauma - Often resolves without intervention - Bruising, laceration - if torn stitch them - Treatment with penicillin IM - Also IBR (bovine herpes 1)

Answer 21

``` - Red urine (redwater) ○ Haematuria - red with clots ○ Haemoglobinuria - red without clots - may need to spin ○ Myoglobinuria - Proteinuria - Pyuria ```

Answer 22

1) bracken fern poisoning 2) post-parturient haemoglobinuria 3) bacillary haemoglobinuria 4) leptospirosis 5) rape/kale poisoning 6) copper poisoning

Answer 23

- Cl. Haemolytic (Cl. Novyi Type D) - Uncommon - Toxaemia, dark red/brown urine - Rapid death

Answer 24

- Leptospira serovar pomona - Leptospira serovar hardjobovis - Enters mucous membranes or damaged skin, localises in kidneys, spread in urine - Affects both calves and adults - Zoonosis (esp… hardjobovis) - Best control is vaccination

Answer 25

- Maintenance host is pig - Cattle are accidental hosts ○ More acute, severe, higher titre - Calves ○ Environmental exposure - wet, alkaline ○ Acute fever, petechiae, depression, haemolytic anaemia and haemoglobinuria ○ High case fatality, after 2-3 days ○ Treatment - streptomycin - Adults ○ Haemoglobinuria uncommon ○ Usually seen as sudden drop in milk production ○ May cause septicaemia and late abortions - Differential ○ Can look like cold water toxicosis -> if cows drink cold water can get red looking urine

Answer 26

- Host adapted to cattle, so cattle have less obvious clinical signs, more chronic, carriers, lower titre - Adults ○ Affects pregnant or lactating cows ○ Mild drop (yellow/orange udder secretion) ○ Abortion may follow - ZOONOSIS ○ Most significant consequence is zoonotic disease -> ongoing BAD flu like symptoms ○ No human vaccine ○ SO VACCINATE THE COWS

Answer 27

- Acute poisoning occurs by accidental exposure to Cu salts - Chronic poisoning may occur on copper rich soils or in areas exposed to industrial contamination - Acute ○ Gastrointestinal signs (diarrhoea, abdominal pain) ○ Fluid accumulation ○ Eventual intravascular haemolysis - Chronic ○ Only haemolytic and icteric signs

Answer 28

- Toxic nephrosis - caused by acorns - Infection ○ Chronic infection may lead to glomerulonephritis +/- amyloidosis ○ Haematuria, haemoglobinuria, myoglobinuria and very alkaline urine will show as +ve proteinuria on dipstick

Answer 29

- Pus in the urine is indicative of inflammation in the urinary tract Treatment - Antibiotics should be chosen on the basics of culture if possible - Prolonged therapy may be required - higher up biliary system the more prolonged the therapy - Ancillary treatment have a role

Answer 30

- “Down cow” = A recumbent cow - “Downer cow” = A cow down in sternal recumbency for 12-24+ hrs without obvious signs of specific cause - “Downer cow syndrome” = The pathology that is secondary to prolonged recumbency

Answer 31

Sternal recumbency - Most fore-weight borne by sternum - Most hind-weight borne by underlying hind limb ○ normally reposition themselves alternating hind limb Lateral recumbency - Regurgitation and subsequent Aspiration ○ a serious potential complication - Risk of positional bloat -> if fluid over oesophageal opening will not eructate and remove the gas

Answer 32

``` - Musculoskeletal/ Neurological ○ Fractures ○ Dislocations ○ 1° Neuropathies ○ 2° Myopathy/Neuropathy - Toxaemia ○ Acute, severe mastitis ○ Enteritis (eg Salmonellosis) ○ Grain overload ○ Peritonitis ○ Metritis ○ Abdominal catastrophes - Metabolic ○ Milk fever (hypoCa) ○ Grass tetany (hypoMg) ○ Both (hypoCa + hypoMg) ○ Pregnancy toxaemia ○ Fatty liver syndrome - Miscellaneous ○ Parturition ○ Exhaustion ○ Emaciation ○ Haemorrhage ○ Hypothermia ○ Severe systemic disease ```

Answer 33

``` - Age & Breed? ○ Middle-age, heifer, older cow ○ Jerseys - more predisposed to metabolic disease - Onset & duration of recumbency? ○ Depends on how frequent observation - Diet (current and previous)? - Parturition (If? When? How?) - Expectations (Intended use)? - Treatments already given? (What? How? How much? When?) ```

Answer 34

1. Observation of posture, responses 2. Physical examination (don’t take shortcuts!) ○ Full clinical examination -> 3. Characterise as: Musculoskeletal/Neuro, Systemic or Metabolic 4. If Musculoskeletal/Neuro: Thorough targeted MS/N exam ○ Downer cow unwilling or unable to stand due to primary musculoskeletal disease or injury ○ May be secondary to prolonged recumbency from primary disease (eg acute mastitis) which is more apparent than 2° injury from prolonged recumbency or attempting to stand

Answer 35

``` Presentation ○ Musculoskeletal/Neuro § Typically bright & alert § In sternal recumbency § Able to ‘creep’ ○ Acute Systemic/Toxic § Sunken eyes & depressed § Sternal, or Lateral if more severe § Observation of mastitis, metritis, peritonitis ○ Metabolic § Depressed or Hyper-responsive/Aggressive § Cardiac signs - HR, strength, rhythm on BOTH sides ```

Answer 36

- Assessment and prompt treatment - Improves chances of getting her up - Need 2+ people to restrain, turn & roll ○ Use cow head to lever - Consider the DDx list as you are examining - Consider taking pre-treatment samples ○ Lithium heparin blood for Ca, Mg, P, CK (not EDTA!) ○ Useful retrospectively if poor response - PROP UP COWS THAT ARE IN LATERAL RECUMBENCY (move neck closer, move back legs under and prop against something to prevent from going back down)

Answer 37

- Frog legged ○ Femoral n. injury; Pregnancy toxaemia - Splay legged ○ Pelvic #; Hip dislocn; Muscle rupture; Obturator n. - Sternal recumbency ○ Musculoskeletal; Mild MF; Mild toxaemia - Lateral recumbency ○ Severe Milk Fever; Severe systemic/toxic disease

Answer 38

Mental status - normal - abnormal - > dull and depressed - > hyperactive - grass tetany

Answer 39

§ Structural damage □ skeletal issues - broken legs or dislocated hips □ No skeletal deformity - neurological defects ® Forelimb -> radial paralysis ® Hindlimb -> obturator, sciatic, femoral § No structural damage □ Positive on ketone urea - pregnancy toxaemia □ Negative ketonuria -

Answer 40

``` □ HR fast ® Mucous membrane brown - nitrate/nitrite poisoning ® Mucous membrane normal ◊ HR weak and hydrated - milk fever ◊ HR strong and dehydrated - toxic ® Mucous membrane pale - anaemic ```

Answer 41

``` - Prolonged recumbency can indicate: ○ Inadequate treatment ○ Misdiagnosis ○ Relapse ○ Concurrent disease or injury - incomplete diagnosis - Prolonged recumbency is due to: ○ Advanced toxaemia/shock ○ Severe back/vertebral/upper limb pain ○ Spinal cord injury ○ Myopathy (usually secondary ```

Answer 42

1) Tail lift -> lifting and stabilising as she gets up Tend to go forward when lift them 2) bagshaw hip clamps - Need to put on tight enough otherwise will fall out of Want to put high enough so support when she stands 3) slings 4) cow jack 5) pelvic lifter - combination of hip clamps and contraction underneath so lift up 6) moo mobile - The point is to bring her up and then let her take her OWN weight

Answer 43

Need a chest strap - Either doesn't want to or have nerve damage - Put strap underneath her chest and wrap around onto prongs on the tractor and lift up again with the hip clamps on as well - This time front is brought up whether she likes it or not and then can see whether she will stand - if so no nerve damage

Answer 44

1) back examination (while in sternal) 2) lumbosacral ligament examination 3) limb examination (roll into lateral)

Answer 45

○ Obvious swellings along back ○ Palpate for pain between transverse processes § Blunt probe, scissor handles, vacutainer tube ○ Palpate spinous & transverse processes § Misalignment (relate to adjacent segment) § Push down on dorsal process (if unstable... BAD) § Abnormal sound/movement when rolled § Fractured thoracic – sacral vertebrae with paralysis □ leads to ‘dog-sitting’ when trying to stand □ Curvature of the spine □ Differences in the position of vertebra to each other or movement of vertebrae

Answer 46

○ Not common § First: □ Hands on tuber coxae and apply forward and downward pressure. Assess for movement § Then: □ Tuber coxae and rectal touching disc btw L6 & S1 § Must not be lifted by pelvis if diagnosed -> just put extra strain on the ligament

Answer 47

``` (roll into lateral) ○ Check for dislocated hip, leg or pelvic fractures, ruptured muscles/tendons ○ Nerve function ○ Manipulate each limb ○ Assessing Nerve & Motor function ```

Answer 48

§ Obturator (L5-L6) □ Passes through pelvis then through obturator foramen □ -> medial thigh muscles… adducts hind limb § Femoral n (L4 - L6) □ Innervates quadriceps to draw hind limb forward § Sciatic . (L6 - S2) □ Passes through pelvic canal initially, then around head of femur, then divides into peroneal and tibial ® Vulnerable to get the sciatic nerve □ Peroneal -> anterior and lateral aspects of foot □ Tibial -> caudal and medial

Answer 49

§ Get in lateral recumbency -> on each side □ She needs to feel comfortable -> NOT ON CONCRETE § Ability to extend and flex to full extent § Abduct in normal range § Crepitus or laxity in hip/stifle -> hand on greater trochanter and moving forward and back and around for crepitus § To ensure no hip dislocation □ Ensure the 3 points (greater trochanter, tuber coxa, tuber sacrale) of the hip are in a triangle with ratio of 1:2 □ As move leg backwards greater trochanter will move forwards and bring forward will go backwards □ With leg slightly forwards and flexed push caudal to greater trochanter and leg will go into extension § Cruciate rupture (pain on stifle flexion) § Palpate full leg for heat/swelling

Answer 50

§ Sensory nerve function (18g needle - stab with this) □ Coronary rim of hoof (skin above coronary band) □ Response? (none; muscle twitch; react; withdraw) § Deep pain (hoof testers) □ Squeeze interdigital (normal strong kick response) § Patellar reflex (hoof testers in lateral) □ Leg flexed (poor; normal; exaggerated) □ Exaggerated reflex is a poor prognostic sign § Motor function □ Stimulate cow to stand (making an effort?) □ Use mechanical lift and assess her input

Answer 51

- Limb fractures & dislocations ○ Relatively easy – crepitus, instability, asymmetry ○ Fractures of femoral neck or shaft ○ Dislocation of hip or hock - frog leg stance - Spinal fractures ○ standing soon after injury, but deteriorate ○ Consider euthanasia if: § Patellar reflex exaggerated (uncommon?) § Vertebral rotation

Answer 52

- Obturator n. injury ○ Lateral abduction of hip (uni or bi) - frog leg stance ○ Usually associated with dystocia. ○ Assess hip! - Sciatic n. Injury ○ Common with dystocia § Generally improvement after 2-3 weeks after caving and past this won't get much improvement ○ Mild ataxia to recumbency with complete paralysis ○ Uni or bilateral – tend to sit on the worst leg ○ Sensory nerve deficit in downer cows § Knuckling of the fetlock, sliding forward with her hindlimb

Answer 53

- Femoral n. Injury ○ Trauma to lumbar region § eg bulling ○ Depressed patellar reflex? Normal pain response ○ Mild stumbling when lifted § Legs move forward as trying to stand ○ Severe - frog legged - Radial n. paralysis ○ No sensation of anterior coronet ○ Flexion of fetlock joint (when lifted) § Assessing muscle tone -> as move legs around is there passive movement - if no tone - flaccid § Extensive test -> can feel the pain but cannot extend the leg § Negative extensive and negative tone - POOR PROGNOSIS

Answer 54

- Accurate prognosis is difficult but important ○ History and clinical presentation ○ Accurate diagnosis of cause and severity ○ Effectiveness of treatment ○ Access to nursing care, weather, cow attitude

Answer 55

○ Good: § Deep pain; Full Tibial sensation; Full/Part Peroneal ○ Guarded: § Deep pain; Tibial/Peroneal sensation reduced/absent ○ Poor: § No Deep pain; Absent Tibial and Peroneal sens. ○ Patella reflex sluggish in moderate to severe ○ Euthanasia if in both legs?

Answer 56

○ Key features are patellar reflex & sitting posture ○ Depressed patellar reflex. If PR exaggerated -> spinal ○ Fractures of vertebral facets -> hopeless ○ Good: able to sit normally but legs out when standing ○ Very poor: legs always in frog leg ○ Cows will crawl initially but this increases damage § Confine these cases to minimise secondary injury - but don't restrict

Answer 57

- Obturator n. injury ○ Prognosis always guarded due to 2° hip dislocation ○ Can put on Hobbles to prevent the legs from getting too far apart as this is where the issues is § Cannot bring legs back together - Lumbosacral injury ○ Good to Guarded – do not lift!

Answer 58

- Non-responsive milk fever ○ Prognosis dependent on duration & muscle damage ○ Physiotherapy (electrostimulation?) - passive movement of the legs - Radial n. injury ○ Improve with time... Treatment & nursing

Answer 59

- Recumbent for hours on hard surface - compartment syndrome - Unable to maintain sternal recumbency - Pronounced abduction of one or both hind legs - DOING THE SPLITS ○ Likely to dislocate hip, break legs or femoral head - Attempt to rise with front legs only - No attempt to rise at all even when encouraged - Extended hind legs so that sitting on stifles - Rigid extension of hind legs (hind claws at elbows) - Not eating or drinking - inability or reluctance to correctly nurse the cow

Answer 60

- Need to quickly address initial cause - NSAIDs: First 24 hours (for up to 3 days?) - Treat the underlying condition - Nursing:

Answer 61

○ Clean, dry bedding (eg 300 – 400 mm deep hay) - COMFORTABLE BEDDING § Don't want pressure points leading to pressure sores ○ Access to feed (good quality hay) & water ○ Turn cow 6 – 10x daily and strip milk (place calf in there to suckle) - worried about mastitis § Often lay on damaged leg so need to rotate ○ Effective lifting 1 – 2x daily § with some weight bearing ○ Confine if femoral n. injury ○ How long to persist? § Depends on cow response, not just time

Answer 62

Moving a down cow - Place into the tractor (bucket) with head halter ○ Don't hip with hip clamps and expect to walk to the area - Move into a nursing area from the paddock Rolling a down cow - If cow cannot roll itself then need to roll 3-6 times a day ○ Hamstring damage - Tuck the hindlimbs in and push the cow from the side (down low over the pelvis) and then pull the hindlimbs out on the their side - Can also use the tail and move it the way want to roll

Answer 63

- Hip clamps ○ Place on pelvis - put on firmly and pick up via the tractor - If standing effectively then leave for a few minutes and check back frequently so ensure cow hasn't sat back down and then suspended full weight on the hip clamps which is bad as described below ○ The frequency of lifting is dependent on how long the cow remains standing each time - If not taking any weight then NOT WORTH LIFTING as will put pressure on the pelvis - will become sore and won't want to get up ○ Leave for a few days and hopefully stronger and will stand

Answer 64

Housing the down cow - Large bedding under cover and restrict to the area of bedding - so cannot move off the hay - 12 foot gate squared area of 30cm of soft bedding - 30 times greater survival rate in a good nursing environment compared to paddock Caring for the down cow - Feed and water is vital ○ Good quality Lucerne hay ○ Water can be hard -> move likely to drink when they are lifted on the hip clamps - Hygiene and good teat disinfectant is important when hand milking the cow - can also place with calf so it can milk ○ Also removal of faeces to help reduce chance of mastitis Assessing the down cow - Ensure no green muck coming out of their mouths if in lateral recumbency -> if so possible that aspiration pneumonia or bloat

Answer 65

- The Transition period is 4 weeks before to 4 weeks after calving ○ This period is a major focus for farmers, vets and advisors - Can be used to prevent milk fever ○ Low calcium diet -> calcium being reabsorbed off bone before calving so when it needs to be done after calving can occur quickly and adaptive

Answer 66

Grey area after calving-> taking back stored fat - ALWAYS LOSE CONDITION AFTER THEY CALVE - At the beginning of lactation not able to eat enough to get enough energy ○ NEED TO HAVE THE STORES to reduce the reduction in the body energy stores ○ WHERE THE TRANSITION PERIOD IS IMPORTANT -> provides the stores - At some point in lactation able to store energy and eat enough energy ○ Positive energy balance -> occurs 1-3months after calve depending on the diet fed

Answer 67

- Hypocalcaemia and downer calves - Hypo-magnesiuma - Ketosis and fatty liver - Udder oedema and mastitis - Abomasal displacements - RFM/metritis - Time to first service and fertility - Subsequent production levels

Answer 68

1. Reduce ruminal disruption - lactic acidosis, ruminal acidosis 2. Minimise macromineral deficiencies - calcium, magnesium and phosphorus - requirement increase dramatically when producing milk 3. Minimise lipid mobilisation disorders - ketosis, fatty liver 4. Avoid immune suppression - trace elements (zinc, iodine, vitamin E and vitamin D)

Answer 69

To ensure these aims are meet - Achievable targets for cow health problem -> standard target that should aim and if not then need to reassess transitional diets Components of an integrated transition diet to consider are: - energy and protein; ○ Too much energy and not enough protein -> stored as fat § Not if body is metabolising fat - Macrominerals and DCAD; - microminerals; - rumen modifiers; and - buffers and other possible additives

Answer 70

1. Milk fever 2. Grass tetany 3. Pregnancy toxaemia 4. Fatty liver

Answer 71

- Plasma Calcium: ○ Free Ca (45-50%) Hormonally regulated and available for use § More is available at lower blood pH ○ Bound to proteins (40-45%) “Already in use” ○ Bound to non-proteins (5-10%) “Already in use” - Blood tests measure total calcium! ○ (This means that blood Ca++ Should be read in conjunction with Total Protein) - Reference ranges vary ○ In general <2mmol/L is worrisome - High Ca++ unusual in cattle

Answer 72

1. Arterial Ca++ levels sensed by parathyroid glands which secrete PTH 2. PTH Stimulates intestinal absorption and renal reabsorption of Ca++ - Short and long term effects (cells produced in the villi have calcium absorption switched on so longer term effects are better - lifespan of 9 days - once those 9 days are up the PTH has been turned off - reduced calcium absorption in new cells -> cyclic effect and possible recurrence of milk fever at this point 3. Some effects mediated via converting Vitamin D to active form. - Calcium resorption from bone is slower in older cows 4. Low blood Mg++ reduces PTH secretion and also tissue sensitivity to PTH

Answer 73

metabolic disease with paresis & hypocalcaemia: - Weakness - Recumbency - Depression of consciousness - Can be fatal - Common disease of dairy cattle (can occur in beef cows) ○ Called severe problem if > 3% of the herd, or cows <5yo affected - Sudden increase in Ca requirement with onset of lactation ○ Colostrum 2.3g Ca/kg; Milk 12.g Ca/kg ○ Onset of lactation increases calcium requirement by 2-4 fold - Subclinical hypocalcaemia is very common

Answer 74

- More properly DCAB (B=Balance) - Diets are electrically neutral, with a balance of cations and anions - Strong Ions are ones that are highly bioavailable and not metabolized - DCAD theory DCAD = (Na + K) –(Cl + S) ○ Lower DCAD the lower the pH the buffer and more protected of metabolic disease - Less is more … - “Anionic salts” added to the diet - Very small changes in blood pH - Measurable changes in urine pH

Answer 75

measured via Urine pH - Easy to measure - Holstein cows should be between 6.2 and 6.8, Jerseys 5.8 -6.3. ○ There are various differing recommendations for this

Answer 76

1. Parturition –most milk fever occurs around parturition. (also transport) 2. Transport -> reduction in the feed -> drop in dietary calcium 3. Age –Mostly > 5yo 4. Milk Production 5. Breed - Jerseys more susceptible 6. Dry period nutrition –diet (blood pH) and body condition

Cattle 4 Flashcards

(100 cards)