Exam 2 - Food Animal Metabolic Disorders Flashcards
1
Q
what is another name for milk fever?
A
bovine parturient paresis, hypocalcemia
2
Q
what production animals are most commonly affected by milk fever?
A
dairy cattle, sheep, & goats
3
Q
what is milk fever?
A
hypocalcemia - failure of calcium homeostasis to maintain normal blood calcium concentration at or near parturition & the onset of lactation due to the high demand for Ca for sudden milk production
4
Q
what is the main clinical sign associated with milk fever in production animals that is different than dogs?
A
FLACCID PARALYSIS
dogs - more tetany/rigid
5
Q
what is a subclinical level seen on labwork that indicates milk fever?
A
plasma calcium concentration <8.59 mg/dL
6
Q
what is the clinical level seen on labwork that indicates milk fever where you will see clinical signs?
A
<6 mg/dL
7
Q
when do we see the onset of milk fever?
A
usually occurs with in 48 hours of calving
twin syndrome - happens prior to calving
8
Q
T/F: a heifer won’t produce as much milk when compared to a 3rd time lactating cow
A
true
9
Q
what animals are most susceptible to milk fever?
A
DAIRY CATTLE!!!! rare in beef
high producing cattle - cows in 3rd or greater lactation because younger animals have more Ca/P stores available for reserve
10
Q
why are older cows susceptible to developing milk fever?
A
the amount of labile bone calcium decreases with age
number of vitamin D receptors decrease with age
11
Q
what breed is predisposed to milk fever? why?
A
jersey cows
they have fewer vitamin D receptors than holstein cows
12
Q
what are calciotropic hormones?
A
hormones that are involved in the regulation of calcium
13
Q
what are the 2 main hormones involved in calcium regulation?
A
PTH & calcitonin - both act together to regulate blood calcium
14
Q
what effect does the release of PTH have on calcium in the body? when do we see the release of PTH?
A
increases blood calcium levels
if calcium falls below a certain set point - PTH is released
15
Q
T/F: PTH responds to LOW blood calcium concentrations
A
true
16
Q
what effect does the release of calcitonin have on calcium in the body? when do we see the release of calcitonin?
A
decreases blood calcium
calcium in the blood becomes higher than set point - calcitonin released
17
Q
how does PTH work to increase calcium in the body? what organs does it act on?
A
stimulates osteoclasts to break down bone reabsorption of stored calcium - releases both calcium & phosphorus from the bone
acts on the kidney & activates vitamin D3 which stimulates the rumen to absorb more calcium
18
Q
how does calcitonin work to decrease calcium in the body? what organs does it act on?
A
bone - calcitonin suppress resorption of bone by inhibiting the activity of osteoclasts causing less bone resorption of calcium & causes increased osteoblast activity leading to more bone deposition of calcium
kidney - calcitonin inhibits tubular reabsorption of calcium leading to the increased rate of loss in the urine
19
Q
what are some examples of factors that may alter the body’s response to PTH or calcitonin in cows?
A
hypomagnesemia
hypophosphatemia
sufficient vitamin D
dietary cation - anion difference
20
Q
how does hypomagnesemia alter the effects of PTH in a cow with milk fever?
A
reduces PTH secretion in response to hypocalcemia - blunts the response because magnesium is needed for PTH to bind to its targeted tissues
low magnesium = less sites for PTH to bind to
21
Q
how can we reduce the risk of hypocalcemia due to hypomagnesemia in a cow with milk fever?
A
provide adequate magnesium in pre-fresh diets to reduce the risk for hypocalcemia
22
Q
how does hypomagnesemia alter the effects of calcitonin in a cow with milk fever?
A
interferes with the activation of vitamin D by inhibiting activity of renal 1 hydroxylase enzyme
so without proper vitamin D, the body can’t properly absorb Ca from the diet
23
Q
how does the dietary cation-anion difference affect cows with milk fever?
A
influences the blood acid-base status which in turn affects calcium homeostasis in the body
24
Q
how does feeding cationic rations affect calcium homeostasis?
A
feeding a pre-partum diet higher in cations (+ charged elements: Na & K) in relation to anions (- charged elements: S, Cl, P)
results in a METABOLIC ALKALOSIS & depresses tissue response to PTH - low calcium, & PTH can’t effectively work to raise calcium levels in the blood
25
how does feeding anionic salt rations affect calcium homeostasis?
feeding a diet that is higher in anions than cations
RESULTS IN A METABOLIC ACIDOSIS - allows calcium carbonate to be released to correct the acidosis & increases calcium levels in the blood!!!!!!!
26
why would you want to feed an anionic ration to get a cow with milk fever into a metabolic acidosis?
if you get them into a metabolic acidosis, calcium carbonate is released to correct the acidosis & simultaneously raises calcium levels in the blood
27
if you are using a dietary cation-anion difference, what should you monitor for?
watch the amount of feed intakes
monitor the cow to ensure they are acidotic - check urine pH
28
T/F: dietary acidity/alkalinity is more important in controlling hypocalcemia than actual calcium intake
true
29
diets high in what increase the risk for hypocalcemia? diets high in what reduce the risk?
diets high in sodium or potassium - cationic rations
diets relatively high in sulfur or chlorine
30
what is stage 1 of milk fever?
wobbly animal that is still on their feet
will see muscle tremors, firm manure, anorexia, & slowed rumen contractions, may have cool ears, heart rate that is quiet/muffled & slightly higher, & temp usually subnormal to normal
31
what is the normal TPR of a cow?
temp - 100-102.5
HR - 50-80
RR - 10-30
32
what is stage 2 of milk fever?
EMERGENCY - down cow that is unable to rise with very cold ears
look for an animal in sternal recumbency, 's' shaped neck, bladder atony (full bladder), low temp <100, increased HR >80, & trouble swallowing/eructating
33
what is stage 3 of milk fever?
EMERGENCY - cow is 'out flat'
bloated (hypomotility/ileus), HR >100, temp <98, poor circulation so ears are ice cold (feel difference between neck & ears), can't swallow (can lead to aspiration pneumonia & death)
34
what would bloodwork look like on a cow in stage 3 of milk fever?
decreased calcium (<6mg/dL), decreased phos, & increased magnesium
35
what stage of milk fever is seen in this photo?
stage 2
36
what stage of milk fever is seen in this photo?
stage 3 - flat out bloated cow
37
T/F: subclinical hypocalcemia at calving (serum Ca <8.59 mg/dL) is associated with impaired neutrophil function & increased risk of metritis/mastitis
true
38
what signs of dystocia may be seen in a cow with milk fever?
uterine inertia, flaccid uterus with no contractures/tone
39
T/F: milk fever can cause a retained fetal membrane or retained placenta
true
40
what animals with milk fever do we see uterine prolapse in?
beef cattle with low grade hypocalcemia
41
is milk fever associated with causing breeding issues in cows?
yes - high % of cows not getting bred back/multiple breedings, etc
42
what treatment is used for stage 1 milk fever?
oral calcium preperations - drenches, place a tube, boluses, or IV
43
why is calcium propionate often picked over calcium chloride for a cow with milk fever? what are the disadvantages of using it?
it is less irritating!!!! safer for a producer to do
doesn't induce the metabolic acidosis & may not be as effective & has a slower absorption
44
what are the advantages of using calcium chloride for a cow in stage 1 of milk fever? what are the disadvantages?
can induce a metabolic acidosis, has a fast absorption, & provides the greatest ability to support blood calcium concentrations
compound is corrosive & a tube needs to be placed into the rumen - will cause tissue necrosis in the esophagus
45
what is the #1 direction you should give a producer with a stage 2 milk fever cow while you're on your way there? why?
DON'T GIVE ANY ORAL MEDICATIONS TO A DOWN COW - risk of aspiration pneumonia
give oral treatment if the cow is standing or sternal & swallowing/ruminating normally
46
why should calcium borogluconate be administered slowly IV?
can cause bradycardia & hypovolemia & death - monitor the heart while giving it
hold it at head height
47
what is the dose used for IV calcium borogluconate?
1gm/100 lb (1-500 ml btl 23% where Ca = 115g)
most give 1 bottle per cow
48
how is IV calcium given to a stage 2 milk fever cow?
given slowly at head height
follow with oral products (bolus, drench, gel, paste) when sternal/up & able to swallow
monitor for hypophosphatemia, hypokalemia, & hypomagnesemia
49
how is a stage 3 milk fever cow treated?
cow that is out flat needs to be propped sternal if possible
treat bloat with orogastric tube or trochar to relieve gas, bloat drench
reduced milking of these animals can cause mastitis
continue calcium supplementation until cow is completely normal
educate client on subtle signs of hypocalcemia (trembling, weakness, ataxia)
50
how should a stage 3 out flat milk fever cow be handled/moved?
sling/mat to move or hip lifters (caution with hip lifters, don't pick up & hold in the air) if they don't get up, put them back down
provide good footing to prevent slipping & injuries
provide shelter, accessible food/water, & hobbies to keep them from splitting themselves
51
what is the prognosis for pursuing treatment in a stage 1 milk fever cow?
excellent prognosis
52
what is the prognosis for pursuing treatment in a stage 2 milk fever cow?
good to guarded depending on the time the animal has been down & their will to live
53
what is the prognosis for pursuing treatment in a stage 3 milk fever cow?
guarded to grave
54
T/F: the longer a cow is down with milk fever, the more damage to muscle & nerves & increased risk for other issues
true
55
how is milk fever prevented using nutrition in pasture dairy operations?
pre-partum diets low in Ca (20gr/cow/day) - very low & not practical in a typical dairy but may work on a pasture
56
what is the most practical prevention method for nutrition used for milk fever in cows?
nutrition management during the dry period using the dietary cation-anion difference adding anionic salts to create a metabolic acidosis in order to increase ionized calcium & resorption
57
if >10% of a dairy herd are affected annually by milk fever, what are you thinking?
herd problem!!!! likely nutrition problem
58
what are some examples of prevention used for milk fever?
ensure the cow has a good appetite at calving
increase Ca in diet within 48 hours of calving
management to decrease stress - look at how the cows are being managed from dry off to close up to lactation groups
calcium supplement administered at calving & 24 hours after (boluses, electrolytes in water, tube them)
producers & veterinarians should discuss with nutritionist
59
when is milk fever seen in small ruminants? why does it occur?
hypocalcemia in pregnant & lactating ewes & does
same as dairy cattle - calcium demand increases rapidly & reserves aren't present in our dairy breeds
meat goats/dairy goats - later stages of pregnancy with multiple fetuses requiring calcium
abrupt decrease in calcium intake & high calcium demand where they body requires 24-72 hours to activate the metabolic machinery necessary to mobilize stored calcium
60
what is the major difference in timing seen when comparing milk fever in dairy cattle to milk fever in small ruminants?
milk fever usually occurs in ewes & does before parturition & less commonly after parturition
61
T/F: milk fever in small ruminants is seen a lot with pregnancy toxemia/animal is off feed
true
62
why do we see milk fever occur in late gestation in small ruminants?
the greatest demand for calcium in the body is because of the mineralization of the fetal skeleton occurs 1-3 weeks pre-partum particularly when multiple fetuses are present
can occur at any time from 6 weeks to 10 weeks after parturition
63
what clinical signs of hypocalcemia are seen in small ruminants?
very acute onset - stiff gait, salivation, constipation, sternal frog leg position with hind legs extended behind, tachycardia
muscle tremors more commonly seen in goats than sheep, but goats will also do the frog leg position
64
what is the treatment for milk fever in small ruminants?
very similar if not identical to dairy cows - calcium borogluconate IV (50-150mL bolus) - monitor the heart for arrhythmias/bradycardia
oral administration
65
what is the active form of vitamin D? what does it do?
1, 25 DHCC - active form
stimulates the rumen to absorb more calcium/phosphorus, reduced excretion of Ca/PO4 from the kidneys
66
what produces PTH in the body?
parathyroid gland
67
what is the major source of calcitonin in the body?
c cells in the thyroid gland - also synthesized in lungs & intestines
68
how does calcitonin work?
responds to high blood calcium levels to decrease calcium absorption
69
what is another name of cholecalciferol?
vitamin D3
70
___ serum phosphorus levels stimulate calcitriol synthesis, whereas _____ serum phosphorus levels inhibit it
low
high
71
how is milk fever prevented in small ruminants?
dietary modifications to increase the calcium:phosphorus ratio (> 1.5:1)
ensure total calcium in the diet meets the NRC along with vitamin D
avoid sudden dietary changes/stressors during late gestation & risk factors for pregnancy toxemia investigated
watch for severe weather changes
72
why do we see post-parturient hypophosphatemia in cattle?
occurs due to high P demands during late gestation & early lactation or can occur due to long term P deficiency
73
when do we see peri-parturient hypophosphatemia in cattle?
occurs at the onset of lactation - widely believed to be associated with peri-parturient recumbency & downer cow syndrome, but not commonly understood
74
what are the initial signs seen in peri-parturient hypophosphatemia in cattle?
initial decrease in milk production, muscle weakness, staggering gait, anorexia, & bone pain
75
what clinical signs are seen in peri-parturient hypophosphatemia in cattle that help you differentiate it from milk fever?
rhabdomyolysis, increased fragility of RBC causing intravascular hemolysis, hemoglobinuria, & anemia
76
how can you differentiate between hematuria & hemoglobinuria?
spin it down
hematuria - blood spot in the bottom
hemoglobinuria - stays the same color
77
how is hypophosphatemia diagnosed?
rule out other causes of intravascular hemolysis & response to treatment
downer cows that don't respond well to Ca may have low P
measure blood phosphorus - concentration in serum can be misleading (many things can mess up results)
78
T/F: in animals with milk fever, their heart rate is increased but their heart sounds are difficult to hear/muffled
true
79
how is hypophosphatemia treated in cattle?
NaH2PO4 & Na2HPO4 are suitable to rapidly correct hypophosphatemia - tube the cow
dose is 60 grams in water or bolus capsules SID or BID
80
T/F: oral sodium phosphate salts increase the plasma phosphorus concentration within 1-4 hours & last 12-14 hours
true
81
what clinical signs are associated with hypokalemia in cattle?
serum potassium concentration <2.5 mEq
muscle fasciculations, flaccid paralysis, & eventual recumbency
pay attention to the animal's history
82
T/F: occurrence of hypokalemia in cattle is rare & has 2 main causes
true
83
what are the 2 main causes of hypokalemia in cattle?
1. isoflupredone 'predef' - iatrogenic cause, steroid commonly given to stimulate gluconeogenesis to treat ketosis in cattle & it causes low potassium (aldosterone like effects)
2. dairy cows not eating >2 days, losing potassium in milk & intake is low
84
why does isoflupredone cause hypokalemia in cattle? what drug can you give instead?
mineralcorticoid with aldosterone like effects causing potassium wasting
dexamethasone - glucocorticoid that doesn't have mineralocorticoid effects
85
what is the treatment of choice for hypokalemia? how is it given?
oral potassium administration!!!!
inappetent lactating dairy cattle should be treated with 60-120 g of feed grade KCl every 12 hours - can be placed in gelatin boluses or given by ororuminal intubation
86
how is hypokalemia prevented in large animals?
oral administration of potassium to inappetent cattle, sheep, & goats
ensure adequate dry matter intake - best method to prevent hypokalemia in adult cattle
use dexamethasone instead of predef for ketosis
87
what is another common name for hypomagnesemia?
grass tetany
88
what large animals are most commonly affected by grass tetany?
beef cattle
89
what is grass tetany?
high fatal disease that is most common in beef cattle - hypomagnesemia
90
what animals are most susceptible to getting grass tetany? why?
adult lactating animals
they are losing magnesium in milk
91
when do we see grass tetany occur?
mainly when animals are grazed on a lush green pasture or green cereal crops
can also occur when lactating beef cattle are fed silage - rare in non-lactating cattle but has occurred when malnourished cattle where introduced to green cereal crops
92
what are the roles of magnesium in the body?
help with nerve conduction, muscle function, & role in the immune system
93
why do we see grass tetany occur?
occurs when plasma Mg concentration drops while the absorption of dietary Mg is unable to meet the maintenance requirements
94
what is the maintenance Mg requirement in a cow? what about in lactating beef cattle?
3mg/kg/day
20 grams/day
95
why are magnesium blood levels dependent upon daily intake?
magnesium is not stored in the tissues - it is present in the bone, ICF, & ECF
96
the only significant magnesium for the ECF comes from what?
intake from the diet
97
what is normal for magnesium levels in the body?
1.7-3 mg/dL
98
what level of magnesium in the body will show clinical signs?
<1.5 mg/dL
99
T/F: grass tetany is often accompanied by hypocalcemia & hypophosphatemia
true
100
what is the epidemiology of grass tetany?
cows in early lactation that are grazing on LUSH GREEN PASTURES high in K, N, & Na & low Mg, <0.2% Mg on a dry matter bases
typically winter grazing (planted fields) spring pastures - fast re-growing pastures (oats, rye, or after rains)
101
what are some other risk factors for hypomagnesemia?
high ammonia in the diet/rumen reduces Mg absorption
diarrhea reduces the absorption of Mg & increases loss of Mg
102
how do other ions in the body affect Mg?
high potassium decreases Mg & Ca absorption from the gi tract
high sodium lowers Mg in the ECF via increased urine excretion (heavy fertilizer)
high crude protein & lipid content diet can decrease Mg
103
what clinical signs are seen in animals with grass tetany?
hyperexcitability/aggression, opisthotonus, muscle spasms/convulsions, ataxia in the rear legs, down cow that starts off sternal with early attempts to rise & progresses to lateral recumbency where the animal flops on their side
death - high mortality rate
104
what is the typical signalment of a cow with grass tetany?
downer lactating beef cow on lush green pasture that is more alert/excitable than an animal with milk fever with muscle spasms
105
which cow do you think has milk fever? what about grass tetany? why?
milk fever - left, calm cow with s-shaped neck
right - grass tetany, muscle spasms
106
what is the treatment recommended for a cow with grass tetany?
magnesium IV - 500mL solution with calcium, magnesium, & phosphorus, 6 grams
NO ORAL MEDS TO DOWNER COW - start with IV & then can do oral if the cow becomes sternal or stands
correct other electrolyte abnormalities, supportive care, supply food/water/shelter if down, & use slings/hip lifters/float tanks - never drag any down cow by any body part
107
why does grass tetany in a downer cow become an animal welfare issue?
can't drag them - bring them food, water, & shelter!!!!
if you can't give proper care - euthanasia
108
what treatments can be used for any downer cow?
float tank can be used for any downer cow once treated appropriately & can stay alert/conscious - labor intensive & expensive
move them properly - have a protocol in place with trained personnel
109
lactating beef cattle require how much magnesium a day?
20 grams a day!!!!
110
what is the prognosis of grass tetany in cattle?
good to guarded in standing animals & poor to grave in down cows (high mortality)
111
how is grass tetany prevented in cattle?
provide adequate amount of magnesium daily
feed Mg salts to animals grazing in risky conditions - begin feeding prior to lush grazing
Mg mineral free choice prior to grazing winter planted fields
avoid potassium fertilization in problem areas
112
is hypomagnesemia common in small ruminants?
no - uncommon in sheep & even more uncommon in goats
113
T/F: hypomagnesemia in small ruminants has the same clinical signs as grass tetany in cattle
true
114
when do we see hypomagnesemia occur in small ruminants?
may be seen during a period of temporary starvation in late pregnancy or early lactation
movement of lactating ewes to lush spring growth pasture (especially green cereal crops) - exactly like cattle with grass tetany
115
what is ketosis?
characterized by an abnormally elevated concentration of ketone bodies in tissues & body fluids that is a common disease in adult cattle
116
what are some rare occurrences of bovine ketosis?
cattle in late gestation & resembles pregnancy toxemia of ewes
117
what is the general cause of bovine ketosis?
cow is in a negative energy balance - early lactation requires a high energy demand in milk (glucose) & if the animal is not meeting those demands through nutrition/feed, a state of negative energy balance occurs
increase in energy output through milk production & decrease in energy input through low blood glucose & fat mobilization for energy
118
what does a cow use for energy if they don't have enough glucose?
fat & protein are mobilized to produce energy for maintenance & milk production, but the breakdown by product of fat & protein are ketones
adipose mobilization is accompanied by a high blood serum concentrations of non-esterified fatty acids
119
what is the pathogenesis of bovine ketosis?
negative energy balance -> body breaks down fat & muscle for energy -> fat mobilization causes increased NEFA's & ketone production
during periods of intense gluconeogenesis (muscle/protein breakdown), a large portion of serum NEFA are directed to ketone body synthesis in the liver - so characterization of ketosis includes high serum concentrations of NEFAs, ketone bodies, & low concentrations of glucose
120
what are normal serum levels of glucose in cattle?
45-95 mg/dL
121
what are the 3 types of ketones? where are the broken down in the body?
acetone, acetoacetate, & b-hydroxybutyrate
broken down by the liver
122
when do we see negative effects from ketones?
when hepatic production & absorption of ketone bodies exceeds their use as an energy source & the liver can no longer keep up with processing ketones
123
what animals are at risk for bovine ketosis?
fat cows - increased risk for fatty liver which interferes with liver function & can slow ketone processing by the liver
124
when is type I primary ketosis seen?
occurs during peak lactation (3-8 weeks) as a result of negative energy balance - cows have a production curve that increases over time & decreases over time
125
when is type II primary ketosis seen?
occurs early in lactation (1-10 days) & is usually accompanied with hepatic lipidosis (fat cow syndrome/fatty liver)
126
what is secondary ketosis? what are some examples of things that may cause it?
results from reduced appetite associated with other problems that occur during the peri-parturient period
retained placenta, displaced abomasum, hardware disease, mastitis, & metritis
127
what are some clinical signs associated with bovine ketosis?
dull/depressed animal - occasionally cow becomes hyper with staggerring, aggression, neuro signs, pica (nervous ketosis)
anorexia, sunken in rumen, stops eating grain 1st, then silage, then hay
normal to mildly low temp (may be elevated in secondary ketosis)
stiff manure, decreased output, rumen contractions are variable
ketone odor
total blood ketones are >15 mg/dL, urine ketones are >84 mg/dL, milk ketones are >10 mg/dL, blood glucose is 20-40 mg/dL
128
how is bovine ketosis diagnosed?
blood total blood ketones blood meter is the most accurate on farm test - producer must be comfortable with drawing blood - used for clinically affected cows
full exam to look for secondary causes
129
how do you make a cow urinate?
use the back of the hand & rub up and down just under the vulva
130
what do trace ketone results indicate in a cow?
subclinical ketosis - not clinical because no systemic signs
131
how is urine/milk ketone testing used by herdsmen for diagnosing bovine ketosis?
easier for them to do - done 7-10 days after freshening
catching primary type II ketosis 1-10 days post freshening with secondary cows with post-partum issues (retained placenta, mastitis, metritis)
132
what is the major objective in ketosis therapy for cattle?
re-establishing normal feed intake & correcting the negative energy balance!!!
treat underlying causes if secondary ketosis - metritis, mastitis, retained placenta
133
what is the mainstay therapy used for bovine ketosis?
providing glucose sources to correct the hypoglycemia
IV 50% dextrose - 1 bottle given IV, never SQ, can repeat once daily (constant drip isn't practical)
134
how is propylene glycol used for treating bovine ketosis?
8-12 ounces are given ever 12-24 hours no more than 5 days - will cause rumen microbes to die off & overdose causes CNS depression
135
how are steroids used for treating bovine ketosis?
predef at 10-20mg/dose every 12-24 hours or dexamethasone 5-20mg IM/IV every 24 hours
helps to mobilize glycogen stores from the liver, decreases milk production which helps decrease the output & helps correct the negative energy balance
136
what other treatments apart from glucose supplementation/steroids is used for treating bovine ketosis?
tube feeding/rumen fluid/probiotics/vitamin b complex
monitor ketones in blood/urine/milk for several days only stopping treatment 24-48 hours after ketones are NEGATIVE
continue to monitor feed intake & ketones in cows so they don't relapse
137
why use insulin for a cow with bovine ketosis that also has fatty liver disease?
suppresses both adipose mobilization & ketogenesis - need to give dextrose/glucose concurrently & monitor (long-acting insulin 150-200 IU/day)
138
what is the prognosis for cattle with secondary ketosis?
it is dependent on the primary inciting cause
139
what is the prognosis for bovine ketosis?
following treatment for subclinical cases - excellent
moderate to severe hepatic lipidosis in conjunction with ketosis - guarded
140
how is bovine ketosis prevented?
avoid over conditioning cows in late lactation/early dry period (BCS of 3.5/5 higher risk for fatty liver & ketosis)
fresh cow program - monitoring ketones in blood/milk/urine on every fresh cow for 7-14 days
watch for post-partum issues
dry & up close management - transition ration, to prevent ketosis, maximize DMI & provide adequate energy density
silage ration - TMR & DMI after calving, manage to increase DMI
141
what is the major difference between pregnancy toxemia in pregnant does/ewes & bovine ketosis?
similar pathogenesis but in does/ewes, happens prior to parturition!!!!!
142
when is pregnancy toxemia seen in dairy goats?
last 4 weeks of gestation
143
what ewes/does are typically affected by pregnancy toxemia?
multiple fetus pregnancy
144
why does pregnancy toxemia occur?
insufficient intake of feed to meet the energy needs of the animal during gestation (each fetus requires 30-40 g of glucose/day in late gestation)
in order to meet energy needs, animal will break down fat stores which releases ketones
145
T/F: sheep & goat fetuses add 70% of their final birth weight in the last 6-8 weeks of gestation
true
146
how does fetus number affect the mother's nutritional requirements during gestation?
singleton - 1.5-2x maintenance
twins - 1.75-2.5x
triplets - 3x maintenance
147
what is the pathophysiology of pregnancy toxemia?
physical capacity of feed intake is reduced by the rapid abdominal expansion of the uterus & without management changes, dam can't ingest enough to support herself or fetus which puts them into a negative energy balance
low blood glucose causes fat & protein mobilization leads to ketone production causing lethargy & loss of appetite
more fat mobilization & ketone production = negative cycle
148
what is primary pregnancy toxemia?
thin or overweight animals with multiple fetuses that are not getting enough calories
149
what is secondary pregnancy toxemia?
other condition causing them to go off of feed
150
what are the clinical signs of pregnancy toxemia in does/ewes?
weakness/not wanting to rise, laying a lot more than other animals in the herd, initial signs are subtle
as it progresses - star gazing, tremors, circling, blindness, etc (looks neuro)
secondary pneumonia, muscle, & nerve problems in animals that are down for a long time
151
how is pregnancy toxemia diagnosed in does/ewes?
blood glucose (low or can be normal), ketones in urine/milk/blood
non-esterified fatty acids can be increased above 0.4 mmol/L indicating hepatic lipidosis causing impaired liver function
152
what differentials should be considered for a doe/ewe with suspected pregnancy toxemia?
hypocalcemia - in recumbent late gestational sheep & goats
hypomagnesemia - common in pregnancy toxemia but should be considered as a ddx
other CNS disease - polioencephalomalacia, rabies, scrapie, listeriosis
153
how is pregnancy toxemia treated in does/ewes?
c-section if possible!!!!!!! lambs/kids may already be dead - if producer wants to save ewe/doe, use a proximal or distal paravertebral block, lay the animal in right lateral, & do the c-section on the left flank
viability of fetuses may be compromised if parturition is induced before day 144
154
what is the normal gestation period in sheep & goats?
150 days
155
successful induction of a doe/ewe with pregnancy toxemia relies on what?
intact fetal hypothalamic-pituitary-adrenal axis
156
T/F: in goats alone, progesterone is made by the CL, so lutalyse alone will induce the animal
true
157
*pregnancy toxemia treatment
158
*didn't get to fatty cow
