Lecutre 7 Flashcards
What makes up the GI system?
Mouth Eosophagus Stomach Small intestine Large intestine
What is the gut microbiome?
The genetic material of all the microbes - bacteria, fungi, protozoa and viruses - that live symbiotically on and inside an animal or us
Where is the largest bacterial populations in animals?
Large intestine (hindgut) of mammals, birds and amphibians
Rarely in the foregut of a few mammals and few birds species
How do you study the gut microbiome?
Shotgun metagenomics (sequences everything)
16s metagenomics (only secquences bacteria)
What is 16s rRNA gene
16s ribosomal RNA gene
All bacteria have them- and it is the gene which is used to type bacteria
Complex structure
Give an example of a few diseases affected by the microbiome
Acne/ Eczema - altered skin microbiome
Autism- different microbes in the gut
Dental cavities - altered oral microbiome
Malnutrition/obesity- altered digestion by bacteria
Why is the microbiome important?
Production of essential nutrients
Breaks down and digests food
Detoxification of foods
What affects the gut microbiome?
Age Sex Weight Temperature County of origin Diet Pregnancy Immune system Treatments e.g. Antibiotics Detoxification of chemicals
How might the county you live in affect gut microbiome?
Likely linked to diets and other stresses
How does gut microbiome evolve?
Gut changes with time
Largely linked to food intake
Different bacteria involved with digestion of different foods
The less complex a diet is the less different bacteria species are required to help digest it
Give an example of a mammals diet and gut microbiome
The giant panda-
23-38kg of bamboo a day
Bamboo contains cyanide
Normal gut anatomy
Increased bacteria which produces rhodanese which detoxifies cyanide
Have a simple gut microbiota due to simple diet
Give an example of an insects diet and microbiome
Leaf cutter ants
Collect leaves and store them so they rot and grow fungus that the ants eat
Fungus detoxifies some compounds in plants
Simple gut microbiota with 4 different bacteria
Give an example of self medication in animals
Lizards eating roots to counteract venomous snake bites
Macaws eating clay to aid digestion and kill bacteria
Female woolly spider monkeys add plants to their diet to increase or decrease their fertility
What are stomach ulcers and what do they do?
Infections can alter the gut microbiota
Stomach ulcers are sores in the gastrointestinal lining of the stomach
Caused by breakdown of mucosal lining
Radically alters gut microbiota
What is digital dermatitis (DD) in cows?
Lameness disease in cattle
Caused by bacterial infection
Similar to CODD in sheep
Alters skin and gut microbiota
