AJVR/JAVMA Flashcards
Excretion times of electronic capsules from the colon of cows
significantly faster from cows with cecal dilation-dislocation > controls
sig. slower in cows w. LDA than all other groups
indications for rumenostomy
rumenal tympany/ bloat, esophageal obstruction, grain overload, access for enteral nutrition
indications for rumenotomy
TRP, bloat, FB, choke, others
prognosis for Bovids undergoing rumen surgery
a favourable prognosis for survival and a fair prognosis for potential return to production
-ostomy had higher percentages of remaining in herd, lower culling percentages on long term follow up
Results indicated that rumenotomy and rumenostomy can be effective in treating or relieving complications secondary to forestomach disorders in cattle
does feeding a direct-fed microbial (DFM) to dairy calves reduce total or AMR coliform counts in faeces or affect ADG?
Results suggested that the DFM fed to the preweaned calves of this study did NOT reduce total or AMR coliform counts in faeces
*Mean ceftiofur-resistant and tetracycline-resistant coliform counts for the control group were significantly lower
monocarboxylate transporter MCT1
might predominantly contribute to the uptake of short-chain fatty acids in the large intestine
monocarboxylate transporter MCT4
might predominantly contribute to the uptake of lactate in the SI
IHC analysis revealed that MCT1 and CD147 were present where in the equine GIT?
in the membranes of enterocytes (in crypts and villi)
Short-chain fatty acids (SCFAs) in equids
–Short-chain fatty acids (SCFAs) produced by microbial fermentation of CHO in GIT of herbivores
–Large amount of fibre in diet increases total amount of SCFAs produced in hindgut of ponies
–Most of luminal SCFAs produced are acetate, propionate, and butyrate
–SCFAs essential for health and function of intestinal epithelium, and account for >30% of total E provision at rest in ponies fed high roughage diet
–pH of hindgut of equids ~6 to 7, so SCFAs mainly ionised and require transporter for cellular uptake (eg MCTs)
SAA increases ?-fold within ?-hours after inflammatory response
10 - >100 fold within 6-12 hours
SAA plasma half life
20-35 hours
haptoglobin increases ?-hours after inflammatory stimulus
12-24 hours
haptoglobin half life
about 3.5 days
horses with ___ have significantly higher SAA and haptoglobin than normal horses
colitis
peritonitis
horses admitted to tertiary hospitals with inflammatory disease have significantly different ___ what 3 values compared to normal horses?
neutrophil count
SAA
haptoglobin
Horses w an increase in SAA WHEN were significantly more likely (OR 7) to be euthanised or develop complications
btwn 24 and 72 h after admission, compared to admission SAA
PRRSV - porcine reproductive and respiratory syndrome virus
-positive-stranded, enveloped RNA virus
-Member of Arteriviridae, species-specific (like other members), and highly variable
-Transmitted through all bodily secretions, incl urine, faeces, colostrum, milk, saliva, semen, and nasal secretions
-Infectious dose appears to be low and variable and is dependent on virus strain, route of entry, concurrent health conditions, and age of pig
PRRSV in Sows
causes abortions, stillborn piglets, mummified foetuses, irregular returns to oestrus, and death
PRRSV in Suckling and growing pigs
preweaning death, lethargy, respiratory tract disease, anorexia, and a decrease in ADG
PRRSV in Boars
Boars of repro age: acute respiratory tract disease, anorexia, lethargy, lack of libido, and reduction in semen quality
PRRSV incidence and infections
Weekly incidence low during spring and summer, high during fall and winter
Exponentially weighted moving average signalled the onset of a PRRSV epidemic during the middle 2 weeks of October each year
Results indicated a striking repeatability in annual PRRSV temporal and spatial patterns across 4 y of data among herds from 14 production companies, which suggested that efforts to control PRRSV at a regional level should continue to be supported
Most coxiella infections in animals are
subclinical
Primary resevoir for coxiella
cattle, sheep, goats
WHAT provided a protective effect against coxiella for goats
farms where primary form of goat carcass disposal was burial
Coxiella testing
Animals – serologic testing not reliable
qPCR of biological matter or fluids is rapid and highly sensitive
causative agent of OPP
small ruminant lentivirus
aka Made-Visna
What kind of sheep flocks are more likely to be infected w OPP?
those maintained on NON-FENCED range
Primary route of transmission for SRLVs
aerosol or direct contact w virus-contaminated nasal secretions from infected animals, and viral transmission is most efficient when animals are in close proximity to each other
The virus is also transmitted vertically from infected ewes to lambs by in utero infection or through milk or colostrum
Iatrogenic transmission of SRLV during milking has also been suggested
OPP
Animals infected w SRLVs are infected for life, but dt long incubation period, generally takes years for csx of disease to manifest
Sheep: onset of csx of OPP is variable and most infections subclinical
Typically, CSx observed in sheep > 2 years old: progressive wt loss despite normal appetite or dyspnoea
Initially, dyspnoea detected only after physical exertion and is extremely noticeable when flock is driven
Affected animals often have a rhythmic jerk of the head w each inspiration and lag behind the rest of the flock
Their nostrils may be flared, and they often have slight nasal discharge
Frequently develop secondary bacterial infections, which may exacerbate the dyspnoea
Over time, infected sheep may develop laboured breathing at rest and spend most of their time lying down
Besides wt loss and dyspnoea, other csx associated w SRLV incl meningitis, encephalitis, muscle twitching, indurative mastitis (leading to the condition colloquially known as hard bag), arthritis, joint swelling and signs of pain (partic of carpal and tarsal joints), and paresis that progresses to paralysis
By time that csx are observed, most organ systems are affected and death is imminent
Economic losses assocated w OPP primarily dt subclinically affected animals w impaired production rather than clinically affected animals à decreased milk production, lower conception proportions, lower birth wts, retarded growth and lower weaning weights, higher proportion of animals culled prematurely (ie lower mean flock age)
Strangles is more likely to be diagnosed when?
Spring > summer
Horses with what clinical finding are more likely to develop purpura hemorrhagica?
anemia
Where are the TRH receptors located?
melanotropes of pars intermedia and corticotropes of the pars distalis; stimulation of these receptors increases secretion of aMSH and ACTH
What temperature must TRH for PPID testing be stored at?
room temperature storage does not affect TRH stim testing
What happens if you repeat a TRH stim test within 24 hours?
second ACTH response will be LOWER
What can be measured to differentiate WNV vaccinated from previously infected horses?
IgM
WNV-specific IgM responses were typically detected in the sero of WNV-infected horses but not sera vaccinated horses
What type of WNV vaccine produced a longer lasting response?
killed
–WNV-specific IgG1 detected sera of most horses 14 d after vx
–Serum anti-WNV IgG1 and neutralising Ab responses induced by the KV vaccines were higher and lasted longer than did those induced by the live canarypox virus-vectored vaccine
What is recommended to measure anti-WNV titres in vaccinated horses?
WNV IgG1 ELISA
What is recommended to measure to distinguish btwn natural infection and vaccination for WNV?
both IgM and IgG1 responses
Actinobacillus pleuropneumoniae
highly contagious, G- coccobacillus that is transmitted rapidly through pig herds in which adequate biosecurity is lacking
Infection with NAD (nicotinamide adenine dinucleotide)-dependent strains of APP can result in signs of severe disease within 12 h after exposure and death within 24 to 36h thereafter
Self-perpetuating inflam contributes to pathogenesis of APP infection in swine
Leukotriene B4, a proinflammatory lipid mediator derived from arachidonic acid, acts as a potent NP chemoattractant and is an important marker of inflam
Similarly, the release of LDH is a prominent marker of cellular necrosis and hallmark of pulmonary tissue damage
Tulathromycin in pigs
had immunomodulatory effects on leukocytes in vitro and anti-inflammatory effects in pigs in experimental models of APP infection and nonmicrobial-induced pulmonary inflammation
data suggested that in addition to its amx properties, tulathromycin may dampen severe proinflammatory responses and drive resolution of inflammation in pigs w microbial pulmonary infections
–In vitro, tulathromycin induced time-and concentration-dependent apoptosis in NPs, which enhanced their subsequent clearance by macrophages
–promoted leukocyte apoptosis and efferocytosis and inhibited proinflammatory leukotriene B4 production, w a concurrent reduction in leukocyte necrosis relative to that of control pigs
–attenuated the degree of lung damage and lesion progression in APP inoculated pigs
polyethylene glycol (PEG)-conjugated bovine granulocyte colony-stimulating factor (bG-CSF)
Cattle treated w PEG-bG-CSF at 10 and 20 mg/kg had significantly fewer cases of clinical mastitis & it did not significantly affect daily milk production or milk composition
was effective for reducing the incidence of naturally occurring clinical mastitis in periparturient dairy cattle
–G-CSF is an endogenous haematopoietic GF that stimulates the production and differentiation of NPs by progenitor cells located in bone marrow
–Daily admin of recombinant bG-CSF to periparturient cows induces pronounced neutrophilia and increased phagocytic and cytotoxic activity of NPs
–PEG used to extend the duration of activity
Calves with high Ab titres (from vaccination) against WHAT TWO viruses had lower odds of BRD?
BRSV and BHV-1
When should pregnant dairy cattle be vaccinated for BHV-1 and BVDV?
At least 60 days pre-calving and again 5 weeks later
Titres of Abs against viral resp pathogens were significantly enhance in both serum (BHV1 and BVDV2) and colostrum (BHV1, BVDV1 and BVDV2) in cattle receiving a KV vaccine (w no adverse reactions) before parturition
dantrolene sodium
lipophilic hydantoin derivative used to treat or prevent various neuromuscular disorders in humans and animals
has been used for tx or pv of anaesthetic myopathy and exertional rhabdomyolysis in horses
**Results suggested that dantrolene premed prevented muscle damage without affecting anaesthetic recovery but impaired CO and precipitated hyperkalaemia and cardiac arrhythmias in healthy iso-anaesthetised horses
–Exact mechanism not clearly understood - likely multifactorial involving suppression of Ca release from the SR and ER and modification of Ca entry into cells
–One of primary effects is inhibition of calcium efflux from these receptors, specifically the RyR1 isoform in skeletal muscle and the RyR3 isoform in neural tissue, w minimal impact on the RyR2 isoform in healthy cardiac muscle
In horses w intestinal ischaemia, mucosal COX-2 gene expression is
increased
___ is highly effective in decreasing LPS-induced PGE2 concentrations
firocoxib
clenbuterol
FDA-approved b2-adrenergic receptor agonist labelled for the tx of RAO in horses
–oral formulation has excellent bioavailability and accumulates in the lungs, liver, myocardium and other tissues
–anti-inflammatory properties and increases the rate of mucociliary transport, + effects on tracheobronchial clearance of inhaled particulates
–When skeletal myocyte b2-adrenergic Rs are stimulated by clenbuterol, there is a direct anabolic effect that causes an increase in muscle mass
–induces lipolysis and inhibits adipogenesis associated w alterations in plasma concentrations of the adipokines leptin and adiponectin in adult horses
–> This increases muscle-directed protein deposition and reduces total body fat, which is generally known as repartitioning
–Clenbuterol causes a switching from a type I, oxidative slow-twitch fibre phenotype to a type II, glycolytic, fast-twitch fibre phenotype, even though b2-adrenergic Rs are expressed to a greater extent on slow-twitch than fast-twitch fibres –> effect lessened when clenbuterol tx combined w exercise
how did long term clenbuterol administration alter body composition
significant decreases in body fat w no loss in body weight
pergolide half life
6 hours - twice daily dosing could be needed
pergolide receptors
synthetic ergot derivate that behaves as a full agonist at dopamine D2 and D3 receptors and has some activity at D1 receptors
One of the first indicators of declining health in cattle is
decreased appetite - can be 4 days before visual signs of sickness are apparent
which pro-inflammatory cytokine may reduce the motivation for cattle to eat
IL-1beta
eosinophilic response in intestinal mucosa of horses w intestinal ischaemia and reperfusion or w strangulation of the jejunum or colon
Eosinophil migration toward and onto the luminal surface was evident in tissues after ischaemia and reperfusion and after naturally occurring strangulating disease of the jejunum and colon, as indicated by a decrease in the number of eosinophils on or near the luminal surface
Ischaemia alone did NOT change eosinophil distribution in the jejunum or colon
Eosinophils responded to mucosal damage evoked by ischaemia and reperfusion by migration toward and onto the luminal surface
Migration may represent an important component of the inflammatory response to injury in equine GI mucosa
Horses with colic and an SAA > ? were more likely to be managed surgically?
> 5 ug/mL
