Production EXAM Flashcards
Coccodia Gross & Histopathology:
Catarrhal enteritis-congestive, +/-haemorrhagic
Small 1-2 mm white/grey ‘nodules’ in intestinal mucosa
Loss of epithelial cells
Villous atrophy, crypt destruction
Coccidia prepatent period:
Can be up to a year
Risk factors for coccidiosis
- Young age
- low body weight (at weaning)
- warm wet environment
- high stock density
- fecal contamination of feed/water
- stressors
Describe a drought feedlot:
a facility designed to provide a controlled environment for livestock during periods of drought. It plays a crucial role in maintaining animal welfare and ensuring sustainability of livestock farming operations during challenging environmental conditions.
Neucleus flock
Describe a lamb feedlot
a facility where lambs are raised for meat production. It comprises pens or enclosures where lambs receive a controlled diet to promote growth and reach market weight efficiently. Proper nutrition and care are essential to ensure the production of high-quality lamb meat.
Describe an export feedlot
These feedlots ensure the animals meet specific quality and health standards required for export. They provide a controlled environment with proper nutrition, healthcare, and handling to produce livestock that meet the criteria set by importing countries, allowing for the export of high-quality meat and livestock products to global markets. Export feedlots play a pivotal role in facilitating international trade and meeting stringent import requirements.
Prepare for export
List some feedlot design considerations:
Regulatory Compliance
Shade and Shelter
Feed and Water Infrastructure
Environmental Impact
Waste Management
Health and Veterinary Facilities
Security
Accessibility
How many serotypes of salmonella are identified?
2500
Enterobacteriaceae
a family of bacteria that includes various Gram-negative, rod-shaped organisms. These bacteria are found in various environments, including the gastrointestinal tracts of humans and animals. Many members of the Enterobacteriaceae family are opportunistic pathogens, meaning they can cause infections when the host’s immune system is compromised. Some well-known genera within Enterobacteriaceae include Escherichia, Salmonella, Shigella, and Klebsiella.
How can we identify salmonella?
Culture
Serology
PCR
Sensitivity
Salmonella pathogenesis:
Fecal oral transmission
Salmonellosis risk factors?
Stress
- transport
- husbandry events
- parasites
- other disease
- bad weather
- overcrowding
- poor hygiene
Coccidia ateology:
Caused by several species of protozoa from the family Eimeriidae
Coccidia pathogenesis:
Ingestion of sporulated oocysts
Salmonella localization:
Where may this occur?
Brain - meningo-encephalitis
Tips of ears and tails - dry gangrene
Gastro-intestinal tract - diarrhea
Repro. tract - abortion
Salmonella clinical signs
- Fever
- DIARRHEA
- Dehydration
- Inappentence
- Weakness
- Weight loss
- Pain (abdo.)
Chronic carriers of Salmonella
Harboring the bacteria in their intestines for an extended period without displaying symptoms - can potentially shed the bacteria, posing a risk of transmission to others.
Salmonella gross pathology:
Varied
congested, red-purple lungs and liver
enlarged fatty liver and thickened and inflamed gall bladder
inflamed abomasum and intestines
enlarged, moist or bleeding intestinal lymph nodes
khaki-coloured diarrhoea, containing mucus or blood flecks
Intestinal fibrinous/diphteric casts
Coccidia diagnosis
History (risk factors)
Clinical signs
Gross pathology
Laboratory diagnosis (FEC) is not definitive as little relationship betw. numbers of oocysts and severity of disease.
Acidosis
Can manifest as either acute or subacute forms, with acute acidosis often resulting from rapid grain consumption and leading to severe clinical signs. Subacute ruminal acidosis is a chronic condition associated with prolonged exposure to high-carbohydrate diets, leading to subtle performance issues. Preventing acidosis through gradual dietary transitions, careful grain management, and access to forage and clean water is essential for maintaining sheep health.
Urolithiasis
Formation of urinary stones in the urinary tract, which can obstruct urine flow. This condition can result from various factors, including diet, water quality, and genetics. Prevention involves maintaining a balanced diet, providing clean and ample water, and managing mineral intake
Vitamin A deficiency
Leads to a range of health issues, including poor growth, impaired reproduction, and weakened immune function. This deficiency is often associated with a diet lacking in vitamin A-rich forage or feed sources. To prevent vitamin A deficiency, it’s crucial to provide sheep with a well-balanced diet
Laminitis
Inflammation of the laminae, which are the sensitive tissues that connect the hoof wall to the underlying structures. Common causes of laminitis in sheep include overconsumption of high-energy feeds, grain-rich diets, or sudden changes in diet. Clinical signs may include lameness, reluctance to move, heat in the hooves, and a characteristic “sawhorse” stance.
What is BRD?
Multifactorial disease
Viral:
- IBR (bovine herpes 1v)
- pestivirus (BVDV)
- parainfluenza
bacterial: (commensals of upper respiratory tract)
- mannheimia haemolytica
- pasteurella multocida
- mycoplasma bovis
What is the usual cause of death for BRD cases?
Bronchopnemonia
What is IBR?
Infective Bovine Rinotracitis
Caused by Bovine Herpesvirus 1 (BoHV-1)
Vaccine available - Bovillis IBR + MH or Rhinogurd BHV 1 (live)
Viral respiratory disease that affects cattle, causing symptoms like fever, nasal discharge, and coughing
Pestivirus
BVDV
Bovine Viral Diarrhea Virus
Respiratory symptoms (including coughing and nasal discharge)
However, it’s primarily recognized as a reproductive and systemic disease in cattle, but it can cause respiratory issues when transmitted to sheep.
Control measures in sheep may involve vaccination and quarantine procedures.
Corona virus
An agent of BRD
Gastrointestinal and respiratory system
Manheimia Haemolytica
Primary BRD pathogen
Pneumonia, high fever, and labored breathing
Vaccination = Bovillis IBR + MH or Bovi-shield MH (live)
most severe - death <24h
Pasturella Multocidia
Pneumonia, nasal discharge, and coughing.
Proper management, including vaccination and minimizing stress factors
Histophylis somni
BRD pathogen
respiratory distress, fever, nasal discharge, coughing, and reduced feed intake
What are the factors (other than (viruses + bacteria) of BRD?
Stress
Mechanical damage to lungs
Immunosupression
Transportation
Breed (bos torus)
Sex (steers)
- Disease occurs 2-3 weeks after a stressor
Clinical signs of BRD:
Flat
Coughing (wet)
Mucus from nose
Droopy ears
Head down
Separation from herd
Sunken eyes
Best chance of recovery is due to:
Being identified early
Gross pathology of BRD:
Kills them quickly:
Purple discolouration of lung fields
1-2 weeks:
emphasematus and fibrous lungs (pasturella)
3-4 weeks:
lots of puss, chronic fibrin tags, some adhesions, plutris
the more time that goes by the harder it is to identify the causitive bug
brisket odemia - heart wont work (histophalus - micro abscesses in heart)
lung microabcesses (micoplasma bovis)
Treatment of BRD:
Antibiotics
NSAIDs = meloxicam (last 3d SQ)
Vitamin C
Change feed
Give a few weeks
Antibiotic treatment for BRD:
Macrolides (not for milk producing animals)
Tulathromycin (draxxin) 7d, WHP 35d
Cephalosporin =
Exceed, Accent & Ceftiofur (last resort)
Allomycin
Control/prevention of BRD:
Manage concurrent disease
Starter diet (reduce acidosis) - high in carbs
introduction protocols - lower stress
allocate enough bunk space (feeding) 11m2/hd
yard weaning & backgrounding
Transportation of poddy calves:
Vehicle and equipment standards, ventilation, temperature control, loading and unloading procedures, maximum travel time, water and feed provisions, stockmanship, and record-keeping.
Transportation of late gestation cows:
can’t travel in the last 4 weeks
>6m preg. needto stop every 12 hours
Transportation of cows with horns:
Cows with horns may require more headroom to prevent them from damaging their horns during transport.
Transportation of Lactating dairy cows:
stop every 12 hours and milked
TEME
Thromboembolic Meningoencephalitis
Causative agent: Histophilus somni
Adhers blood vessels in brain
Causes convulsions
What is backgrounding?
Keeping cattle in paddocks next to the feedlot
Yard weaning
Done prior to going to backgrounding
getting them used to the feedlot setting/feed
Vaccines
BVDV
BVDV
Mannhymeia haemolytica
2 vaccines - bovillis MHS
Bovi-shield
Pestigaurd
Backgrounding is better protection than vaccination
What should feedlot diets do?
Avoid high non protein nitrogen (NPN)
Avoid acidosis in the starter period
Support the immune system
add vit. E
add zinc
add ammonia
add vit. B
add zinc
IBR
part of the BRD complex
Infectious Bovine Rhinotracheitis
Bovine Herpes virus 1 (BHV1)
severe (death) tracheal lining really sore
one of the most commmon causes of pneumonia
Very infectious (nasal and oral droplets)
NSAIDs really important
Vaccination
Malignant Catarrhal Fever
Looks like?
IBR on steroids
caused by Alcelaphine Herpes virus 1
No treatment
Sporadic
Immediatly cull on humane grounds
Shipping Fever
Pasteurella spp. or Mannheimia
occurs post transport
having their heads up bacteria enter lungs
usually no viral involvment
Necrotic laryngitis
“honkers”
Diptheria
fusobacterium
Shade requirment
2.5m2/head
Coccidiosis
Treatment
Ionophores
(rumensin, bovitek)
work by altering na/k ion channels in bacteria and other organisms
Salmonella
treatment
Trisoprim (TMS)
Salt toxicity
held off water - dehydrated
high Na con. in CSF
when regain axcess to water they gourge - water rushes to CSF and causes brain swelling
Listeriosis
Listeria monocytogenes
comes from silage
CNS clinical signs
droopy ear/eye
facial paralysis
PEM
Polioencephalomelacia
Bacteria get “acid shocked” in low pH of acidic rumen, release exoenzymes & thiaminases - breakdown B1 compound
caused by increasing ration too quickly or high carbs or sulfur content
Lights on and no ones home
Otitis
Pasturella or mycoplasma
spread through blood
oxitet/eardrops
Urolithiasis
water belly
Different types of crystal formation
ca:phosp ratio
if low - struvite crystals (sand like)
if high - calcium carbonate crystals (round stones)
Oxalate pastures - oxalate crystal
- straining
like a blocked cat
Viral
Infectious Bronchitis
RNA virus - envelope
Viral
Avian Influenza
RNA virus - envelope
zoonotic
Exotic animal disease
High mortality
migratory water fowl carriers
horozontal
H7N7 strain
Viral
Newcastle Disease
envelope
RNA virus - envelope
Exotic animal disease
no disease in Aus
vaccine avalible
neurological signs
Viral
Infectious Laryngotracheitis
DNA virus - envelope
Viral
Fowl Pox
DNA virus - envelope
Bacterial
Fowl Coryza
Avibacterium paragallinarum
Sinusitis
PCR
vaccination
Bacterial
Fowl Cholera
Pasteurella multocidia
re-emerging animal disease
swollen combs/wattles
sudden death
Infectious Bronchitis (IB)
endemic
Infectious Laryngotracheitis (ILT)
Notifiable disease
Comes back when immune system is low
histopathology or PCR
coughing up blood
vaccinate layers
Bacterial
Chlamydiosis
Bacterial
Chronic Respiratory Disease (CRD)
All respiratory diseases with unknown cause
Avian pathogenic E.coli (APEC)
peritonitis
perihepatitis
Antibiotics not registed for any animal in australia:
- Fluroquinolones
- Colistin
- Fourth generation Cephalosporins
Bacterial
Mycoplasmosis
pathogenic strains
M. Gallisepticum
M. Synoviae
M. Meleagridis
Mycoplasmosis
Transmission
Both vertical and horizontal
Mild in Aus - make vaccines
clinical signs may vary
difficult to culture - do PCR
treatment won’t elliminate the bacteria - can researfice
For respiratory disease
What antibiotics do we use in chickens?
Amoxicillin Trihydrate
Lincomycin
Nil WHP
Fungal
Respiratory Mycosis
Aspergillus fumigatus
Occurs in chicks
no antifungal registed
fungal nodules in lungs
Enveloped viruses are more ……. in the environment?
Fragile
as well as more sensitive to fetergents and disinfectants due to lipidic nature of the envelope
Anatomy of respiratory system (chicken)
Conjunctiva
Nostrils
Nasal cavity
Nasal sinuses
Pneumatic bones of skull
Larynx
Trachea
Bronchi
Lungs
Airsacs
Pneumatic bones
Respiratory illness clinical signs:
Chickens
Clowdy airsacs
Chlamtdiosis
(Psittacosis, ornithosis)
chlamydia psittaci
notifiable
zoonotic
doxicyclin - not registed in chickens
Fowl Pox
can vaccinate
plaques in mouth (look like scabs)
B cell response
Ag components are displayed (with MHCII)
T-helper recognise the same ag, binds & produces cytokines
Activated B cell forms plasma & memory cells
plasma cells produce antibodies and memory cells await another invasion
Primary Lymphoid organs
- Thymus
- Bursa of Fabricius
- T cell precursors
- B cell precursors
Secondary
Secondary Lymphoid orgains
- Spleen
- bone marrow
- Harderian gland
- CALT (conjunctivial-associated lymphoid tissue)
- BALT (bronchial-associated lymphoid tissue)
- GALT (gut-associated lymphoid tissue
Chickens do not have lymph nodes (except water fowls)
Chicken immunoglobulins
Ig Y (IgG)
Ig M
Ig A
IgA
Mucosal membranes
fades quickly
Ig Y (G)
Ig M
Systemic
Types of vaccines in chickens:
Live vaccines:
- Eye/nose drop
- beak dip
- spray
- wing web
- drinking water
- in ovo (day 18)
- injection (IM)
Types of vaccines in chickens:
Inactivated vaccines:
- SC
- IM (may cause lesions due to harsh adjuvants)
Neoplastic
Marek’s Disease (MD)
Most common - may have pathogen without dissease
Herpesvirus (1,2,3(HVT) strains)
classic paralysis (attacks the siatic nerve (superman))
spread through the feather follicles
3 Presentations of Marek’s disease (MD)
Classical disease Neurolymphomatosis
Acute form
Inflammatory form
immunosupressive
Infectious bursal disease (IBD)
RNA virus
non-enveloped
serotype 1 = disease (not in Aus)
immunosupression
1. inapparant <3 weeks
2. Acute 3-6 weeks
3. Severe (any age)
Avian Lymphoid Leucosis
ALV
retrovirus
incubation 4-6m
horizontal (fecal-oral)
reduced weight, weakness, anorexia
histopath, PCR, serology
no vaccine
can we differentiate MDV and ALV
physical signs
sometimes
ALV - no nerve, muscle, skin, eye lesions
MDV - T cells - herpesvirus (DNA)
ALV - B cells - oncovirus (RNA)
Chicken infectious anaemia
vertical transmission
non-enveloped
immunosupression
virus replicates in bone marrow
CD4 & CD8 T cells in the spleen
vaccinate parents
Inclusion Body Hepatitis (IBH)
Adenovirus
lots of serotypes
IBH Fowl Adenovirus (FAV)
gross lesions:
* swollen liver, yellow, mottled with petechiae
* kidneys and bone marrow pale
* bursa and spleen small
vertical and horizontal transmission
