Showing posts with label Their. Show all posts
Showing posts with label Their. Show all posts

Friday, 15 April 2011

The Venoms of Snakes and Their Local Reactions

The Venom
Snakes in general are known for one very important feature they possess asides crawling uniquely on the floor as their means of movements. That particular feature is their venom. What is the venom all about? How and why is it poisonous and deadly to their victims? These, we will all consider.

Venom is modified saliva and 0.25 to 1 ml of it is injected into the victim when the snake bites. Enzymes such as phosphatidases, proteases, cholinesterases, hyaluronidases, ribonucleases, deoxyribonucleases, ophioxidase, lecithinase and erepsins are present in the venom. In addition, the venoms of Cobra and krait also contain non-ensymatic components like basic polypeptides which are highly neurotoxic. These toxins produce neuromuscular block.

The viperine venoms contain hemorrhagic, necrotic, coagulant and hemolytic substances leading to extensive damage to several tissues. Lesions are due to intravascular coagulation, fibrinolysis, damage to the vascular endothelium and extensive necrosis. The venoms of sea snakes are neurotoxic and they also cause extensive necrosis of the muscles.

The speed of action of the venom depends upon the site of injection and the amount of venom injected. If the venom directly enters the blood stream, the effect may be rapid and lead to sudden death. In most of the cases, the absorption of venom is slower and especially in viperine bites with extensive local reaction, considerable amount of venom may remain locally to be absorbed into circulation in due course.

The severity of en-venomation depends upon the circumstances of the bite. Bites sustained during the early part of the night are generally more serious since the poison sacs of the snake are full at this time. Bites through clothes are less dangerous. Children and underweight persons suffer more than normal adults since the concentration of the venom is relatively higher in them. Violent physical activity helps in disseminating the venom rapidly and thereby worsens the prognosis.

Clinical features: Severe fright and mental agitation leading to tachycardia, sweating, hypotension and even vascular collapse are prominent features soon after the bite. These nonspecific symptoms may be seen in all snake bites.

Local reactions: Local reactions are more prominent in the case of viper bites and less so in others. Intense pain, swelling and violaceous discoloration develop within minutes and often serosanguinous (bloody) fluid exudes from the fang marks. The edema and discoloration spread proximally and in a few hours vesicles and hemorrhagic blebs may appear. Rarely, gangrene may supervene.

Monday, 11 April 2011

Let's Help Feed Those Backyard Birds Returning From Their Winter Migrations!

It's onto March! Let's hope the 'In like a Lion, out like a Lamb' comes true!

For those birds that have wintered 'up nort', they must have had quite a time of it. Record snowfalls and bitter cold sure makes it hard on them. But for those birds that migrate south during the winter, March is the start of their migration back 'up nort'. Here are a couple of neat ideas you may want to consider throughout the month of March to help their migration out.

First, try putting out fruit Apple halves, browning bananas, even overly ripe grapes will all work. Fruits are not typically found outdoors in March (at least not in the upper midwest), so the early arriving tanagers, grosbeaks, and orioles will find them a great treat They may even be willing to stick around a few days later if they know you are serving up their favorites.

Secondly, here's an interesting tip we have used. Take an old cupcake baking pan and attach it to your deck rail or other feeding platform. Either nail or screw it in place, or better yet, wrap it with small bungy cords to secure it in place(that way you can easily remove it or move it, and you wont leave holes in your decking). Next, place different foods in each cupcake bowl. Then watch the activity! You can see which bowls get emptied the quickest and which birds enjoy each treat. You may just discover that a ripe grape is preferred over a brown banana or that a piece of an old donut beats any fruit you offer up.

And to combine 2 wild bird food favorites into 1 (Berries/Cherries and Peanut Butter), here's a popular and effective homemade recipe:

This is a great project for 3 year olds or older - with supervision

Complexity - Easy

Time to Complete - just 5 to 10 minutes

Needed - Bargain-brand granola bar (your backyard friends wont know you bought generic), Peanut Butter (with our without nuts is fine) and Chopped Berries or Cherries

Step 1 - Spread peanut butter onto a granola bar.

Step 2 - Roll the bar over a plate of chopped berries or cherries, pressing them in place.

Step 3 - Place the bar in your open roofed, platform feeder. Watch the enjoyment begin!

Stay Warm, Spring is just around the corner, and Enjoy your backyard birds!