The immune system is a very broad and complicated subject that can baffle most brains (mine included) as you delve into the complexities of the system. Luckily though, the basic concepts are fairly straight forward and should give you some understanding as to why you need to look at your pets health from the pet's point of view and not yours! We can start by saying that, in our case (i.e. dealing with animals) the immune system is what protects the animal's body from harmful substances. These may be bacteria, viruses, fungi, toxins or even, in the case of cancer cells,products of the animal's body. For a simple illustration, imagine that the animals body is a country, then the immune system would include customs and passport control at the border posts, the army patrolling the borders to prevent illegal entry or an invasion, and the police within the country working on crime prevention. The border itself represents a barrier to entry as do the skin and mucous membranes of our pet. A lot of potentially harmful substances get stopped right there. Those that have the right passport and visa are allowed in (food, water, oxygen etc). However, some insurgents(infections) might bypass the border control, or have false passports and it is the patrolling army's job to find these and arrest them. Similarly, some inhabitants of the country might indulge in criminal activities (e.g. cancer cells) and it is up to the police to identify these and get rid of them. Now remember that the country (the animal) is under constant threat from outside sources (infectious agents) and from internal criminal activity (production of undesirable cells).To cope with this situation and survive, the passport and customs officials, the army and police have to be constantly ready for action. They have to be well equipped, well trained, fit and motivated!Any slip, and the door is opened for something to go wrong (disease).This is why it is so important that you get the basics of petcare right because these factors support the development and maintenance of a competent and primed immune system! In addition to the "frontline troops", the immune system also has a massive "administration" system in place that deals with functions such as provisions, logistics, recruitment and so on. For example. When an "intruder"(possible infectious agent) slips across the border(enters the body) and is caught by the patrolling army (a branch of the immune system), the prisoner is taken to a safe place (another part of the immune system) for questioning.The authorities (immune system) go through all their files to see if they recognise this intruder.They also have to decide what sort of threat, if any, this intruder poses to the country (the animal). If they can identify the intruder and decide it is a risk,then they know what they are dealing with and can alert all patrols, border personnel etc to be on the look out for this type of intruder. If however they do not recognise this intruder (a new infectious agent), then they first have to study the intruder, find out how it operates, train personnel to deal with this new threat, and then get that knowledge out through the organisation. This obviously takes longer to do and involves a lot of "paper work" and "personnel" other than the front line troops. What we have described above is also the basic theory supporting vaccinations. By vaccinating your pet, you challenge the immune system. The first vaccination makes the immune system aware of the potential threat and allows it to prepare and train it's defences. The second and subsequent vaccinations allow the immune system to test that training by activating the defence mechanisms it has prepared. It also serves as a reminder to the front line troops as to which intruders they need to be on the lookout for. Unfortunately, the immune system is not a full proof system. Like any other system it can develop glitches and malfunction or it can simply be overwhelmed. When this happens, disease results and we look to other resources (surgery, medication etc) to help the immune system win the battle. Ironically, in some cases the immune system can work against a happy outcome. Organ transplants are an example. Here, although the new organ is obviously vital for the survival of the recipient, the immune system will go all out to get rid of it because it is perceived as being an intruder! Thus the need for a host of drugs to suppress the immune system and allow the new organ to function in the new body.But of course, the immune system is then operating less efficiently and this opens the door for other "insurgents" to invade the body. The immune system is a complex, amazing system that we still do not understand fully. However, that doesn't mean we can't do our best to ensure that it is in the best possible shape throughout a pet's lifetime by applying sound basic pet health principles. |
