Cove Rattery (and More)

Fourth of July Goodies

Cove Rattery — Thu, 10 Jul 2008 02:13:32 GMT

For those of you that do not know, I am a foodie. I know it's an add thing to say since I really don't eat meat, but still, I am. I love cooking, trying new foods, and learning all things food too. If I wasn't so desperately in love with the idea of animals for my career, I'd be a pastry chef. That is my fantasy life for sure! Anyways, it has been suggested to me that I should document some of my trials and errors, as well as the successes. So, why not start now. I made a Star Spangled Fruit Tart for the holiday weekend when I hosted dinner for my immediate family. This time, I took pictures! Until then, here is the recipe.

Recipe's Ingredients: 1 tube refrigerated sugar cookie, 1 8oz. package cream cheese, 1/4 c. sugar, 1/2 tsp. almond extract, 1 c. blueberries, 1 c. raspberries, 1 c. halved strawberries
I use the term 'recipe's ingredients' because I did some tweaking. I didn't have strawberries and I also didn't bother measuring either of the berries out. I made the star pattern on the cookie with the blueberries and just filled the interior with the raspberries.

Instructions: Preheat oven to 350 degrees. Press cookie dough onto an ungreased 12" pizza pan. Bake for 10-15 minutes until golden brown. (For me, this took around 20 minutes actually.) Cool before spreading on the cheese mixture. In a mixing bowl, mix the cream cheese, sugar and almond until smooth. Spread this on the cookie. Arrange the blueberries in the shape of a star (outline) in the center of the tart and around the border of the cookie. Fill the star with raspberries. Refrigerate until ready to serve.

My final thoughts on this one was that it was tasty but I've had much better. I would not make this one again, but it was whimsical and fun for the fourth, and it was easy and fast too!

What I'm reading in 2008

Cove Rattery — Mon, 23 Jun 2008 18:55:38 GMT

I will continue to update this post throughout the year, altering the date each time I do. If there are additional notes about any particular book, it will link to it. So, here ya go!

Little Bitty Mousie by Jim Aylesworth
Library Mouse by Daniel Kirk
Cow Moo Me by Stephen Losordo
Body Movers 2 by Stephanie Bond
The Ultimate One-Stop Vegetarian Cookbook: Simple Meatless Recipes for Great Food by Mark Bittman
Tall, Dark & Dead by Tate Hallaway
Dead Sexy by Tate Hallaway

A vegetarian cookbook?!?!

Cove Rattery — Sun, 27 Apr 2008 16:38:49 GMT

So, I'm reading this book called How to Cook Everything Vegetarian: Simple Meatless Recipes for Great Food by Mark Bittman, and I'm thrilled with it. First of all, you heard me correctly. I am indeed READING a cookbook, but this is SO much more than a cookbook. In fact, as a recipe guide, I've yet to use it at all. There are no full color, mouth-watering pictures. No black and white photos or celebrity faces either. There are a few illustrations of food prep techniques, but that's about it. But, what is lacks in 'looks', it makes up for in content. Let me secondly say that the book costs a mere $35.00 full retail price, but I've had my copy from the library for about a month now. I will be buying this one though, but I will also be checking for a deal somewhere... likely Amazon or a coupon via Barnes and Noble. Another nice thing that I should mention from the get-go is that this author is NOT a vegetarian. He is just an author and cook that has become aware, as many Americans have, that we need to get healthier, and a diet high in vegetables, fruits, whole grains, and legumes is the way to go. So, this book is not only for vegetarians, but for the growing trend of 'flexitarians' too, as well as health conscience meat eaters that want a break from a pounds of animal protein and fat in their diets every day. I'm all for that!

Anyways....what is it that makes this book so grand?

1. Ingredients. This book is NOT unrealistic, so you will not find it describing only organic products, exotic produce, and foreign cooking techniques. This is a book to the real at home cook. He does discuss that you should try to purchase the best you can within reason and budget, but this isn't always necessary either. In fact, some olive oils for $5 are just as good as a $30 bottle. He does list 8 ingredients that you must not skimp on though. They are extra virgin olive oil (must be extra virgin), parmigiano-reggiano (the real stuff, not the powdered crud in the green shaker), real soy sauce (it's only ingredients should be soy, wheat, salt, water, and bacteria) , yogurt (whole milk please), dry pasta (from Italy only), basmati rice (from India is best), salt (kosher or sea), and peppercorns (grind your own..it makes all the difference). He also has a "bottom line" list, which is 25 ingredients that any vegetarian pantry should stock. Here they are: Extra virgin olive oil, neutral oil like corn or grapeseed, vinegar (which he details later in the book), real soy sauce, rices (long and short-grain), pasta, beans (dry and canned), spices, flours (all purpose and wheat), cornmeal, canned tomatoes, dried mushrooms, eggs, real parmesan, lemons or limes, butter, aromatic veggies (garlic, onion, shallot, carrot, celery), dairy (milk, yogurt, buttermilk), nuts, seeds, baking soda, baking powder, cornstarch and yeast, standard condiments (ketchup, mustard, mayo), and long-lasting produce (potatoes, apples, oranges, etc.). Okay, so it's more than 25 technically, but you get the picture. He also lists an additional 16 for an ideal pantry. Those are capers, seaweed, miso, sesame oil, bread crumbs, coconut milk, dried fruit, wine, parsley, sour cream, peanut butter, frozen vegetables, black beans, sake, fresh scallions (ginger and chilies too), and exotic condiments (curry, horseradish, hoisin, etc).

2. Equipment. This is a nice section of the book too. For someone like me that struggled for weeks on which cutlery and pots/pans to purchase, this was a great confirmation of the decision I ended up making. It discusses the essentials for cookware and cutlery, and the differences between the types, including pros and cons. I myself settle on Calphalon Contemporary cutlery and Calphalon One Infused Anodized cookware! They were good choices for me, but the pieces will come slowly as the price was inhibiting. But, in this book, he goes much further, discussing essentials beyond your stovetop cookware too. Loaf pans, pie plate, springform, ramekins, cake pans, muffin tins, bundt pan, souffle dish, cookie sheets, tart pan, roaster, baking sheet, square pan, and gratin dish. WOW!! From there, it's more in depth about small utensils. I would say that this section is valuble to those just starting out, giving them a guideline for what they need, but also helpful to those like me that want to round off an ideal kitchen collection as well. He really does well to cover everything from a whisk to a mandoline to a microwave to a melon baller to an ice cream machine to a skewer! This section had me jotting down things for about an hour.

3. Techniques. I really enjoyed this section. I love my knives, but I always battle the 'proper' technique, so this was helpful in not only how to hold and rock a chef knife's blade, but how to get the perfect chop, mince, julienne, and even chiffonade! It also covers the ten essential cooking techniques, and as simple as some may seem and often as they may be used, this section was still informative and interesting to read. Those 10 techniques, by the way, are boiling, steaming, sauteing, stir-frying, deep frying, braising, roasting, baking, grilling, and broiling. I admit I have never broiled in my life, but I certainly would like to now! Of course, food safety, leftover ingenuity, and reheating are in this section too!

4. Salads. Of course, as would be expected, this section starts with a 'lexicon' of salad greens, and covers most of the basics from price to prep and storage, as well as some of the less known. By this point in the book, if you are reading it like a book, you SOOOO want to make something. So, I'm off to try that... more to come later.

Floozie's babies are here

Cove Rattery — Mon, 16 Jun 2008 18:18:51 GMT

So, this afternoon, it finally happened. Floozie gave birth to a litter of thirteen babies, and all are doing well. This litter will produce all dumbos in fawn and rex, with standard, rex, and double rex coats. All details and daily pictures will be posted on my rattery website here: http://www.coverattery.com/rats.htm.

Weekday nights are back in business

Cove Rattery — Wed, 26 Mar 2008 20:26:11 GMT

So, I must admit than I am a TV junkie. I have shows that I love and pretty much freak out when I miss them. The weekday nights now have a lot to offer me, and I find myself glued to the TV for too many hours now.

MO 8:00pm - House
TU 8:00pm - American Idol on FOX (yeah, yeah, I know)
TU 9:00pm - Beauty and the Geek on CW
WD 8:00pm - Wifeswap
WD 9:00pm - American Idol on FOX
WD 10:00pm - Top Chef on Bravo
TR 9:00pm - Lost on ABC (if it's a repeat, I'm all over Celebrity Apprentice - course it's less of thrill to me with Baldwin gone!)

Obstacle course for rats

Cove Rattery — Wed, 26 Mar 2008 18:38:03 GMT

Bear with me here because these are not my own ideas.. these are ideas taken from past issues of the Rat Fan Club's newsletter, which I'm compiling here so I don't have scraps of paper everywhere!

The five common obstacles, according to the North of England Rat Society, are the bridge, the see-saw, the hoop jump, the weave poles, and the long tube. Ideas can be seen here: www.neratsociety.co.uk/1stshow3.htm, www.furryfeet.co.uk/ratalbum.htm, pipsa.flaming-trout.com/fences.html (not in english), and www.midlandsratclub.org/shows.shtml(search agility).

The easiest obstacle is the hoop jump. It can be done as simply as using an empty cardboard center from a roll of packing tape and a squat, sturdy bowl. Tip the bowl upside down and tape the cardboard roll to the bowl's base. There's your hoop jump! To teach your rat to go through this, you need to lead the rat through the hoop with food. Make sure the rat is all the way through the hoop before you reward with a treat.

The next one to try is the A-frame. Make it from thin wood or heavy cardboard. Ramps average from 6 - 12 inches long. They should be 5-7 inches wide. The entire ramp will be like a triangle, with a base for support. If using wood, be sure to sand it well. Glue or tape together and cover the ramp with a non-slip surface. Teaching the rat is down also would food lead and reward.

There is also ideas for hurdles using legos! The rat must jump a series of hurdles in order to get their treat!

The last one I wanted to add here is a test for the rat's sense of smell more than a part of agility. In a large cardboard box, put a small bowl with a scent in each corner. Place the rat in the center to find their preference. Either rotate the scents each trial or put the rat in facing a different direction. You can do food smells or not, but be sure nothing is toxic. Record the order the smells are visited for 60 seconds. This was even done as a science fair project, with the student hypothesizing that rats would prefer sweet smells! Kind of neat!

Sexy rat stuff

Cove Rattery — Sun, 27 Apr 2008 14:42:32 GMT

Just so more bits and pieces of info I didn't want to lose track of...

1. Anogenital distance

· Genital opening to anus

· Distance relative to hormones pup was exposed to during development

· Males have a larger distance due to an increased testosterone exposure

2.      Anogenital statistic

·        Anogenital distance (mm) divided by weight (g)

·        Can predict males and females

3.      Rat reproductive system and environmental components on behavior

·        21 day gestation in the rat; 1^st trimester is 7 days

·        During 1^st trimester, sexual differentiation is ambiguous, that is, the pups are bipotential for sex. Sex is set in the following trimesters.

·      Environment effects the degree of maleness of femaleness in the pup. Neighboring fetal pups and hormonal exposure shape development. There is a position effect of hormones on growth and development within the uterine horn. The uterine horn holds the pups next to each other in a common placenta.

4.      Rat sexual behavior

·         Female proceptive behaviors – hopping and darting, travel and kick, ultrasonic singing and ear wiggling. The female typically initiates mating.

·         Female receptive behaviors – lordosis (reflexive female mating posture - back arched down, rump up, and tail to the side, which physically rotates the vulva to a backward facing position), the stereotypical arching of the back in an inverted manner with head and hindquarters elevated.

·         Male pre-copulatory behaviors – stereotypical grooming and washing, investigating female for chemical cues.

·         Male copulatory behaviors – mounting (male's copulatory position), intromissions, and ejaculation. The value of intromissions is believed to be the stimulation of egg release.

·         Post-ejaculatory interval – the refractory interval following copulation. This period of rest or inactivity after ejaculation is displayed by both sexes. In the male, it lasts 5 – 10 minutes. In the female, it lasts 30 seconds – 1 minute. This

·         Male rats have a tonic hormone secretion, which stays fairly constant. Female rats have a cyclic hormone secretion. She will mate at the peak of the hormone curve or estrus. The estrus cycle is 4 days in length.

References:

http://www.spflrc.org/user/rats/Glossary.htm

http://www.spflrc.org/user/rats/norway_rat_ethogram.htm

Lange, Gary. Ethology Lecture. Saginaw Valley State University.

What I read in 2007

Cove Rattery — Wed, 19 Mar 2008 15:40:39 GMT
Here is the list for 2007. Here we go!
Lean Mean Thirteen, Smitten, Hot Stuff, Thanksgiving, Metro Girl, Rocky Road to Romance, Back to the Bedroom, Love Overboard, Plum Lovin', Full House, Full Tilt, Full Speed, Full Blast, Full Bloom, and Full Scoop by Janet Evanovich
20 Times a Lady by Karyn Bosnak
Inkspell by Cornelia Funke
The Ethical Assassin by David Liss
Can a Guy Get Pregnant: Scientific Answers to Everyday (and Not-So-Everyday) Questions by Bill & Rich Sones, PhD
The Gospel of the Flying Spaghetti Monster by Bobby Henderson
All I Know About Animal Behavior I Learned in Lochmann's Dressing Room by Erma Bombeck
Shopoholic and Baby by Sophie Kinsella
Body Movers by Stephanie Bond
Hypochondria Can Kill by John Naish
Beach House, Lifeguard, and Violets are Blue by James Patterson
The Hypochondriac's Guide to Horrible Diseases You Probably Already Have by Dennis DiClaudio
Harry Potter and the Deathly Hollows by J.K Rowling

Interesting (behavior)

Cove Rattery — Sun, 27 Apr 2008 14:33:48 GMT

This is just a few more notes on some of the things rats love to do with regard to behavior.

One such thing is caching or stashing. This is most often done with food items. The rat will collect items of food, and run to deposit them somewhere else. The cycle is often repeated many times. Usually, food is hidden in a select location for that particular rat, with corners, nestboxes, and protected locations being most common. This behavior can sometimes be seen in nesting as well, with the rat dragging any soft or preferred nesting material into their sleeping areas. Female rats tend to do this more often than males. The reason why this stashing occurs is thought to be an adaptive trait for rats that would need to secure food for later use in times where food may not be as readily available.

Another item worth mentioning is digging. Rats do not burrow like some animals, but still seem to have a blast digging holes and pulling handfuls of dirt this way and that.

One of the most important things a rat does is sleep, typically doing so for upwards of 15 hours a day. Rats are considered crepuscular, and are most active and dawn and dusk hours. Rat positions can vary just as much as the rat themselves can, and depends on temperature, location, substrate, social situations, etc. Some prefer sleeping alone, some in groups, some in enclosed areas, and some out in the open. It all depends on the individual rat and environment.

A couple other notes on things I've seen and find interesting are these: the flank mark and tonic immobility. Flank marking is a way to scent mark but uses the flank rather than facial or genital secretions. The flank is rubbed against objects, and the rat typically leans sideways on a vertical structure, pushing the body sideways against that object while stepping forward. It is done in familiar environments, as urine marking is done more often in new environments as well. Tonic immobility is interesting as well, and occurs as a freezing behavior when the rat has pressure applied to certain areas like the upper back or nape. It can be seen when holding a rat with pressure on these areas, but is also the explanation for the immobility when a rat is on its back, having contact pressure on this area from the floor. The immobility tends to last longer in less dominant rats, interestingly.

http://www.spflrc.org/user/rats/Glossary.htm
http://www.spflrc.org/user/rats/norway_rat_ethogram.htm

Bruxing, gnawing, etc

Cove Rattery — Sun, 27 Apr 2008 14:33:25 GMT

Bruxing is a fascinating thing that rats do. The sound that you hear is from the repetitive grinding of the incisors against one another. This not only sharpens and maintains the length the teeth, but also seems to be done in times of relaxation and in times of stress. This is often accompanied by the justly named, eye-boggle. The eyeball literally vibrates in and out of the socket as the masseter muscle below it is moving. During bruxing, this muscle, which passes beneath the eye, causes the jaw to move up and down. These contractions can also vibrate the eye at the same time, and is most often associated with contentment and pleasure.

The process used to brux is much different than when a rat gnaws or chews, though, involving different muscles and tooth placement. The three jaw muscles used for chewing and gnawing are the masseter, but also the temporal and pterygoid as well. When a rat gnaws, its bottom jaw is jutted forward so the incisors line up and the molars are no longer together in a chewing position. The ability to move the jaw forward when gnawing gives the tooth a beveled edge, which is why they are so sharp. The additional iron compound in the teeth, giving them the orange appearance, also keeps them strong and sharp. Rat's teeth and rootless and grow continuously, so it is important to their overall health that their teeth also be healthy. Different from gnawing, when a rat chews, the molars are aligned to grind food and the incisors are no longer lined up.

http://www.spflrc.org/user/rats/Glossary.htm
http://www.spflrc.org/user/rats/norway_rat_ethogram.htm

Play behavior in rats

Cove Rattery — Wed, 26 Mar 2008 18:26:23 GMT

Just as is the case with dogs and other animals, there is a lot you can learn about future temperments when a rat is very young. You do this by observing play! If you watch a group of rats at play, you will note that there are certain individuals that are initiating more of the play and are the ones that generally attack and pin another cagemate. But, as these rats grow into adulthood, it is actually the more passive youngster that becomes the dominant rat. This is believed to be due to the defensive strategies learned by the rat that was pinned so often as a younger rat. Sexual maturity seems to be the turning point for both the dominant and the passive rat, essentially switching roles into adulthood. This play dominance is NOT an indicator of aggressiveness, though, as the play fighting is not associated with serious fights. There is a big difference in mannerisms with serious fights. Playful attacks are associated with targeting the nape of the neck, while more serious attacks target the rump and flank. Rats play as adults too, often in boxing or sidling positions, but again with target to the nape of the neck. Play fighting is juvenile in nature even as adults, and will often include one rat exposing it's belly or chasing and fleeing behavior. As adults, these behaviors continue, but may be replaced by boxing, kicking, and forequarter pivoting. Rats tend to peep and squeak at one another in play fighting too. With serious fights, hissing and loud, long squeaks of warning are more common. Typically, defensive moves include open-mouth display of teeth, hissing, nosing off, tail writhing, piloerection of fur (poofing), boxing, sidling, kicking, nipping at the face, and belly up postures. Interestingly, though, the belly up is not a submissive posture in rats. It is defensive in the way that it covers the areas of the rump and nape at which attacks are directed, whether play or not. Offensive moves include chasing, sidling, kicking, and biting.
And what about play dominance heirarchy with larger groups of rats? In this case, there is an alpha or dominant single rat and those around that rat take on a couple different roles as subordinates. Playful contact between these individuals is an important aspect of friendship and bonding. But, there are two main strategies that subordinates take. One is for the subordinate to maintain close contact with the dominant rat (beta subordinate) or they avoid him (omega subordinate). Those that avoid the dominant rat tend to be more aggressively treated and are more likely to leave the colony if possible, but this rat is also in a stronger position to become the dominant rat should the current one leave or pass. The beta is more submissive and more tolerated by the dominant rat, so has more access to resources as well, however this rat has less of a chance of becoming a dominant figure and will likely remain a subordinate to another dominant rat even if the current one leaves or passes. Temperment is influenced by genetics that reflect on a rat's boldness, and therefore, it's choice of dominance/subordinance.
Seperate from this, but still very much a part of the picture, is allogrooming, or the grooming of another rat. Nibbling during grooming is associated with play and will often illicit peeps of protest from the groomed rat. However, grooming around the face is also a social behavior, maintaining bonds between rats. This differs from self grooming, which involves scratching with the hind feet, grooming the face, flanks, and tail, and nibbling. Excessive nibbling can turn into barbering, where fur is actually nibbled off. Bald spots are most typical on the head, face, neck and shoulders and barbering can be done by one rat to another as well. Self barbering can also occur on the forearms and chest and is usually indicitive of either mites or a high fat diet. Calorie deficiencies, hormone imbalances, and stressful situations can also cause the barbering, though.

References:
www.spflrc.org/user/rats/WildRats.htm
www.spflrc.org/user/rats/RatPlay.htm
www.spflrc.org/user/rats/norway_rat_ethogram.htm
www.spflrc.org/user/rats/Glossary.htm

Pigments & Dilutes

Cove Rattery — Mon, 23 Jun 2008 19:08:12 GMT

First, recall that the pigment cells produce two types of pigment: eumelanins (brown/black) and phaeomelanins (yellow/red). And also, note that the switching back and forth of pigment production is what produces the Agouti color-banded hairs, and this is the wild-type or dominant allele.
In non-agouti rats, the only pigment produced is eumelanin. There is no agouti proteins in these rats, and it is that lack of protein that keeps the switching of pigments from occurring. And for my purposes here, it is just that simple!

And on to the pigment mutations.

A mutation in the brown locus on a rat also affects just the eumelanin by altering an enzyme that normally converts brown colored pigment to black. The result is a rat with brown coloration. In the agouti, the produced color is not standardized; and in the black, this is chocolate. The brown mutation is recessive and occurs like this:
BB/Bb - no dilution
bb - diluted to chocolate

And, on to another mutation. Sooner or later, I swear I'll get through all my little notes here and there..some day!

This time, we'll look at mutations in the chinchilla gene. This gene codes for an enzyme that is responsible for pigment production. If a rat has this mutation, the enzyme cannot function, and there is no pigment at all, producing what is known as an albino. The albino is white with pink eyes and is commonly referred to as Pink Eye White or PEW. The chinchilla gene is interesting though, because there are mulitple types of mutation that can occur, giving way to a variety of genotypes AND phenotypes. The mutations are recessive and occur in this way:
CC/Cc - normal pigmentation
cc - no pigmentation/albino

The other mutations are a bit different though. They do affect the enzyme production, but do not halt it altogether. A diluted color results and the resulting enzyme is fragile and temperature dependent. This type of mutation occurs in lots of animals from cats to rabbits to rats and results in the siamese and himalayan color patterns. The pigment forms only on the cooler areas of the body, like the nose, ears, feet, and tail. Pink eyes are also typical of these animals. The genotype for these rats are as follows:
c(h)c(h) - diluted color/siamese
c(h)c - more diluted color/himalayan

These rats tend to have poorer vision than their normally pigmented counterparts, as well.

References:
http://www.spflrc.org/user/rats/CoatColorMutations.htm
http://spoiledratten.com/articlebasicgeneticscolorcont.html
http://www.afrma.org
http://www.bms.ed.ac.uk/research/others/smaciver/Myosin%20V.htm
http://www.sgul.ac.uk/depts/anatomy/pages/MRholdings.htm

The hoodies

Cove Rattery — Wed, 19 Mar 2008 15:15:00 GMT

I feel like I'm on a role here, going through all these stacks of paper about this and that, and getting the ideas in a collection that makes sense. Of course, the piles barely look dented, but I'm trying at least!!

Hooded Rats...
The hooded locus is a piebald locus, producing the white color or absence of pigment in specific areas of the coat. There are two alleles on this locus: H and h. The capital or dominant H produces a solid color, while the lowercase or recessive h produces the lack of color. A rat that is HH will be solid and without white markings on the coat. Hh is where there is the most variation, from the Irish to the Berkshire and everywhere in between. The body of these rats will be colored, but there will be anything from a small spot of white on the belly to an entirely white belly. Finally, the hh rat will be hooded. Again, there is some range here too, based on other genetic modifiers. In general, a hooded rat has a colored head and dorsal stripe, while the rest of the body is white.
But, how does the color appear on the body like that from a genotype? Well, simply, this hooded gene affects how pigment cells are distributed on the body. The mutation causes a delay in the migration of cells, but before I get to far, let me explain this migration. As an embryo develops, there is a clustered area of cells along the neural crest (dorsal area) that migrate to different parts of the body. These cells then differentiate to form everything from organ tissue to pigment cells (melanocytes). Within these cells, there are vesicles called melanosomes that actually contain the particles of pigment. When these vesicles travel to the edge of the cell, they lyse and release the pigment into the growing hair, where we then can see this coloration. Now, the coloration itself is a whole seperate animal (agouti banding vs. black mutation) that will be addressed some other time! At this point, lets just say that there are two types of pigments, the yellow-red ones called phaeomelanins and the brown-black ones called eumelanins. And, to further complicate things, the pigments can switch back and forth in production, creating the banded agouti colors. But, I digress! As stated earlier, the hooded mutation delays the melanocyte migration, so the areas of the body furthest from the dorsal area do not have the pigment cells, so they remain white or unpigmented. Because there is much variation seen with the hooded allele, it is proposed that there are different alleles that help determine how much delay occurs, creating the irish, bareback, berkshire, etc. Interesting stuff for sure!

References:
http://www.spflrc.org/user/rats/CoatColor.htm
http://www.spflrc.org/user/rats/CoatColorMutations.htm
http://www.ratbehavior.org/ExperimentalCoatTempmt.htm#Hooded
http://embryology.med.unsw.edu.au/Notes/ncrest.htm
http://links.jstor.org/sici?sici=0027-8424(19880715)85%3A14%3C5325%3ACAADPO%3E2.0.CO%3B2-H

DaVinci and Inkheart

Cove Rattery — Sun, 18 May 2008 02:44:00 GMT

DaVinci - I must say, as I'm just about done with the book, I don't really see what the big deal was. Are we so confused by the concept of fiction now that we will take offense to everything? Give me a break folks! It's a book..a good book..nothing more and nothing less.

Inkheart - This is the first in a trilogy of books, and I'm enjoying it thoroughly! It's my understanding that they are also making a movie due to release in 2008 of this particular book, and Brandon Fraser plays one of the main characters! From what I've read so far, this should make for an excellent movie too!

Rex mutations

Cove Rattery — Wed, 19 Mar 2008 15:12:07 GMT

And now for my favorite mutation of all...the rexing genes!! Rex mutations basically slow the growth of a rat's hair in the anagen phase of growth, mainly in the guard hairs, so the hairs are shorter, thinner, and not perfectly formed, resulting in the curly appearance of the rex rat! Currently, there are two different genes that are known to cause the rex mutation. The first is very rare in the fancy rat community and pet trade, but will still be noted here. It has been hypothesized that the wavy mutation still exists, but exists in the same lines as those with the rex mutation, creating a 'rex' rat that also has the recessive wavy alleles. In these rats, the fur is quite sparse, and is more like a downy, thin covering on the body. It is distinct from both the other mutations as they occur independently. I will also make mention of a couple others in the end, there are now assumed extinct mutations. The fertility and survival rates of curly haired rats is normal.

Wavy mutation (wv) - recessive
Wavy rats look just like rex rats, but the hair is a bit thinner and shorter. Their whiskers are curly and bent. The significance of this mutation is that it is recessive, unlike its rex counterpart.

Rex mutation (Re) - semi-dominant
Rex rats are a passion for me, and I personally breed them. The coat of a rex rats can vary quite a bit, but in general, they are wooly looking. The coat goes through a series of changes, starting soft and fluffy in weaning rats to a rougher texture through early molts. The hair is usually of normal thickness, but because of the curly nature of the hair, you can often see the skin underneath. Because the rex mutation is semi-dominant, when two copies are present, another look all together is produced. This is often referred to as the double-rex. Around 4 weeks of age, a double-rex rat will begin to rapidly lose it's coat, starting at the head and shoulders and moving down the body in the normal pattern of hair growth/cessation of growth. A new coat will come out and that new coat will also be lost as the rat molts. This may occur over the rat's entire adult life. Males are less affected than females, and tend to retain a bit more hair over all. The hair of a double rex rat is also easy to pluck out, and the whiskers are shorter than that of a rex.

Other mutions causing the rex appearance...
Curly-1 (Cu-1) is a dominant trait resulting in a slightly wavy coat, that is usually relaxed by adulthood, but the coat remains softer than that of a rat with a standard coat.
Curly-2 (Cu-2) is a dominant trait resulting in a similar coat to Curly-1, but with a more distinct curl, but one that still relaxes a bit as the rat ages.
Kinky (k) is a recessive trait on Chromosome 4. Adult coats on this rat are shorter, rougher, and more dense. And, due to easy breakage of the hair, bare patches develop in areas like the shoulders and hips. These rats have a lower fertility and shorter lifespan than other rats.
Shaggy (Sh) is a dominant trait on Chromosome 2. This mutation gives an appearance somewhere between the two Curly mutations, and there is some interaction with this gene and the others, because when both are present, the curling of the hairs is more significant.
Other terms heard in the rat fancy include 'teddy rex' and 'velveteen', but these are more or less cute names for variations of phenotype. Most likely, these are the same mutations that have been selectively bred for a certain rex type, but at this point, it is unclear. It is also possible, although less likely, that these are new mutations or re-occurances of the formally assumed extinct mutations.

References:
http://www.spflrc.org/user/rats/CoatTypes.htm

The hairless

Cove Rattery — Wed, 19 Mar 2008 15:08:00 GMT

I promised mutations, and mutations ye shall receive. For any of these mutations that cause hairlessness, the rats are fertile, but they all tend to have problems with raising the babies to weaning age. All these 'hairless' rats have whiskers, and some hair on the body, but it is short and sparse, and cyclic growth, loss, and regrowth can occur in any of these rats. The only real way to tell what type of hairless you have (if you have them) is through blood work. The nude rat has no thymus, so will have low or no T lymphocytes. The fuzzy rat will have signs of kidney disease.

Nude locus... Rowlett nude (rnu) - recessive on Chromosome 10
Rats that have a mutation in the nude locus have sparse hair on the face and head, but not really anywhere else on the body. Before these nude rats are weaned, they may also have a flakiness to their skin, but it does later become smooth. Nude rats may also grow hair during their lifetime, but will lose it again shortly. So, what exactly is this mutation and what does it do beyond the physical loss of hair? The nude locus codes for a protein that is required for normal development of skin, hair, and thymus, so the mutation effects all three. Nude rats have no functioning thymus, which leads to immune deficiency and a smaller stature, on top of their hairlessness and possible skin abnormalities. These rats rarely make it past 9-10 months old.

Fuzzy locus... (fz) - recessive on Chromosome 1
Fuzzy rats have short, rough hair as youngsters, but by around 2 months of age, the coat is either very sparse or completely hairless. By 6 months, they are usually smooth-skinned and will stay that way through adulthood. If it can be said that one of the hairless mutations is worse than another, this one would be it, with the highest rate of physical abnormalities. The most prevalent and most deadly is kidney failure. Fuzzy rats suffer from chronic kidney disease, and ultimately, this is what causes the early death in these rats. Most only live to 16-20 months of age. Tumor incidence is also affected in fuzzy rats and, while they do not have a higher risk of them, they do develop them earlier in life than furred rats. Adrenal glands also tend to be cystic and dental malocclusion is extremely common, to the extent that more than 50-75% of fuzzy rats will need regular tooth trims to eat and survive somewhat normally. Of course, the skin and hair is affected as well. Cysts can form in the skin because the skin tends to be more thickened, and it is this thickening that is the reason for the hairlessness (and cysts) in these rats. The hair cannot penetrate the thickened skin, so the follicle can become inflamed. One of the mutations of the fuzzy allele is the Charles River hairless, but it should not be confused with any other mutation. It is still the fuzzy mutation that causes this type of hairless rat. In fact, this is where there is some confusion. There is NO true hairless mutation in the rat, as there is in the mouse. The only currently known mutations in rats that cause hairlessness are the three discussed here.

Shorn locus... (shn) - recessive on Chromosome 7
Shorn rats have a patchy, thin coat as adults, usually with a mask of hair on the face, and more ragged spots of short hair on the rest of their body. As weaning babies, they usually have short hair on the body, but not on the face, but by around 8 weeks they are usually hairless and the facial pattern of fuzz gets the mask like look of the adults. This mutation not only effects hair, but also effects kidney function, and the mutation creates an error in the coding for keratin, which is why the hair loss occurs. Most shorn rats have abnormalities in the kidneys and heart, are smaller than normal rats, and tend to die at a younger age averaging 10-14 months old. The shorn rat is the least likely of the three to be found in the pet trade or rat fancy.

References:
http://sdb.bio.purdue.edu
http://www.biology.ccsu.edu
http://www.spflrc.org/user/rats/CoatTypes.htm
http://www.rmca.org/Articles/truehairless.htm

Hair growth in rats

Cove Rattery — Wed, 19 Mar 2008 15:11:45 GMT

So, from forever ago, I'm going to work on some of those 'ideas' in my head and start clearing out some of the paper clutter I have at home with all my little notes. This is as good of a place as any to put those thoughts, right? This time, it is from looking through papers on hair and coat types in rats. So, I'll start compiling some of the information I've gathered here until I get into researching it deeper. So, a mini article to keep me on track...

The part and type of hair that I'm interested in is the part on the body that contains pigment. The middle layer of a hair is called the cortex, and this is where the pgiment is contained within keratinized cells (cells that are thickened with the protein, keratin). There are two types of hair on the body. The guard hairs are longer and are used for waterproofing and protection. The undercoat hairs and shorter and more dense and help insulate the body. But, before we get much further, it is important to note how the hair is produced within the follicles. Follicles are complete with blood, nerves, tiny muscles (responsible for piloerection), and matrix cells, which are the cells that keratinize and push upward to form hairs. The follicle goes through a specific gene-regulated growth cycle that is important as well. There are three phases: anagen, catagen, and telogen. The anagen phase is the active phase of hair growth. The catagen phase is when the growth is shutting down. And, the telogen phases is the rest phase, and it is during this time that hair can also fall out. Since genes and hormones play a big role in these growth stages, it is easy to imagine the mutations and changes that can affect the hair growth patterns. For instance, the anagen phase is sensitive to thyroid hormones, and if too low, the follicle will enter the catagen phase prematurely, leading to hair loss. This is just one of many examples though. Hair growth patterns are also very interesting. Not all follicles go through the same phase at the same time. The phases follow in a wave like pattern from the front end of the body to the back, and from the belly to the back. That is why you can see the molting pattern on a growing rat. It is the mid point between the phases of growth in the follicles, and it can produce some interesting results!

So, now the fun part...mutations!!

That will be the next installment!

Reference:
http://www.spflrc.org/user/rats/CoatTypes.htm

Megacolon

Cove Rattery — Wed, 26 Mar 2008 18:22:51 GMT

This is just the tip of the iceberg with this subject, but it is the quickest one for me to jot down a couple notes and be able to pitch some more paper laying around the house, so now, on to the controversial....

Megacolon...

During development, neural crest cells that originate along the embryo's back, migrate to other areas. Some of these neural cells are responsible for ennervating the colon. If this migration is delayed or disrupted, these cells do not get where they need to go, resulting in improper control of the colon.. in other words, megacolon can develop. The colon eventually fails as feces back up in the system, and a bloated, painful rat is the result. Megacolon is a fatal condition. This is not unique to rats, and is seen in mice, horses, ferrets, dogs, and even humans. They may not involve the exact same mutation, but the result is the same due to some interruption in normal cell migration to these areas of the body.

So, why the risk associated with distinct white patterns and spotting in the coat? Pigment cells also originate and migrate in the same manner as the neural cells, and even those in the inner ear, do during development. So, again, if there is a disruption, these pigment cells will not reach their destination either. You end up seeing the absence of pigment in the areas furthest from the neural crest, such as the face, stomach, feet, etc.

In rats, there are two known gene mutations that cause this. One is a recessive spotting lethal gene that actually results in a deletion of a gene that is responsible for melanocyte formations and cell dispersal in the intestinal region of the body. The result is an unpigmented forehead (a blaze typically) and a lack of normal nerve tissue in the colon, leading to megacolon. The other mutation is white spotting and this is a dominant gene. This mutation knocks out a protein that is responsible for many things, but particularly, in this case, is involved in melanoblast formation and migration. Its affect can be seen with a wide range of depigmentation from a blaze to a complete absence of color (black eyed white). These rats are also prone to anemia, reproductive problems, and deafness because of some of the other things the knocked out protein is responsible for (i.e. blood stem cell production, etc). In regard to megacolon, this particular protein is also involved in intestinal contractions and is critical for normal motility of the small intestine. This abnormal contraction of the intestines can be mild in these rats to severe, therefore megacolon.

Megacolon, although associated with 'high-white', can be caused by other factors as well, and the presence of 'high-white' does not always indicated megacolon either. Blazes and markings such as these can also be caused by other genes that do not affect, with their mutation, any of the elements that later cause intestinal issues. Efforts still continue to breed lines of blazed and marked rats with low to no incidence of megacolon, but much is yet to be learned.

References:
http://www.spflrc.org/user/rats/CoatColorMutations.htm
http://vtpb-www.cvm.tamu.edu/Larr_Mouse/pigment.html
http://www.spflrc.org/user/rats/megacolon.htm

The senses

Cove Rattery — Wed, 26 Mar 2008 18:19:06 GMT

Hearing...
Rat's have hearing that is much more sensitive than a human's. They hear softer sounds and can hear into the range of ultrasonic too. Where humans can only hear up to 20kHz, rats can hear up to 90kHz! In fact, most of the rat's vocal communication is above or below the range that we can hear. Distress vocalizations are a good example of this in the high range. They occur in the 20-50kHz range and are just barely audible to people. For example, if you have ever seen a rat cornered by another where the mouth is gaping open to show the teeth, but no apparent noise is coming out, there is infact sound there. If you listen closely enough, a constant, high-pitch whine will be heard, though. The same types of ultrasonic distress calls are made if infant rats are stepped on or if a rat is in pain or under stress. Shorter, even higher pitched vocalizations are reserved for positive situations and have been recorded during play, feeding, and mating. In fact, research has been conducted to show that rats even 'laugh'!
Some aspect of hearing also occurs with the whiskers (which will be visited more thoroughly when I discuss 'touch'). Because the whiskers resonate with certain frequencies of sound dependent on the whisker's length, they help to interpret sounds as well. It is actually this fine sensitivity that allows rats to use their whiskers in the manner they do, allowing a very detailed picture of objects within the reach of these specialized hairs. Having said that, it would also make sense that rex or hairless rats would have a lowered ability to detect fine textures and interpretations of their environment.

Taste...
The primary function of taste for a rat is to make sure that foods are safe to eat. Rats use sampling to test small portions of new foods to be sure they are edible. When something is put in the mouth, the saliva dissolves it and stimulates the taste buds to detect one of five tastes: salty, sour, sweet, bitter, or umami). The message from that particular taste is relayed to the brain to produce a behavioral response, from feeding to aversion. Food preferences and 'safe' associations are formed in some interesting ways. For example, the foods eaten by the mother will be preferred by the pups as tastes are transferred via the milk. Associations are made to avoid some foods as well, both individually if an item made that rat ill in the past or socially if other rats around it are eating or avoiding a particular item. Social acceptance of items can come from the people that rats trust as well!
Smell...
A rat's sense of smell is extremely fine tuned and the world of smells to a rat is unlike our own. Rats also use scents to learn, and can distinguish slight differences in odors, from food sources to individual rat scents.

You may notice your rat sniffing deeping at a surface once in a while too. It appears they are pressing their nose into what they are smelling, and they are actually using a secondary scent organ, the vomeronasal organ, to pick up molecules of scent. This organ is typically used to 'smell' pheromones, which are most concentrated in urine and other bodily secretions. It is this chemical scent that tells a rat everything they need to know for mating, social order, overall health, gender, age, and more! Urine marking then becomes an important part of rat behavior. It is the urine that leaves these chemical cues in any environment the rat visits. In regard to sexual behavior, an interesting find is that the pheromones also contain cues for other members of a group. For instance, the presence of a largely female pheromone results in a delay or suppression of estrus cycles, whereas male odors speed up the rate of puberty and stimulate the estrus cycles of mature female rats.

Behavior in rats is largely affected by scents, but this is not limited to mating behaviors. Aggression, mothering, and food selection are just a few of those behaviors.

As a side note of interest, albino rats tend to have a lowered sense of smell.

Sight...
Rats can see two types of color (blue and green) compared to the human's three types (blue, green, and red), but they can also see in some of the 'blue' spectrum that humans cannot, the ultraviolet. Rat's vision is called dichromatic but technically includes a bit more due to the ultraviolet range they can also see in. But, this is only the color sensing aspect of vision. Another important thing to consider is light and dark perception, since rats tend to take their cues from brightness over color in general. A rat's vision is blurry because of the relatively low number of cones present in the rat eye's retina. These cones are what lends to sharper vision. So, rats will only see slight clarity of an image up to a few feet away. And, an albino rat's vision is worse yet. Since the iris of the eye is unpigmented, it does not block incoming light and creates a washed, patchy, light and dark images versus one with somewhat defined edges to the surrounding environment. This is no suprise to learn that rats really depend on their sense of touch and smell to guide themselves around their world then.
As a human comparison regarding color alone, a rat would have a similar view of color as a red-green colorblind person. This does not take into account the bit of ultraviolet that rats can see though, and does not consider how vision is affected by color saturation and brightness. But, it still gives a beginning idea as to how our rats see their world. Regarding the reason why rats can see in the ultraviolet range, there are a few theories, however the one most widely accepted and the one that makes sense to me personally is this; ultraviolet light is most abudant in the dawn and dusk hours, those hours of highest activity for rats.
As stated previously, beyond color, a rat's vision is blurry. A item must be within 7 cm to truly be visible, whereas a human's depth of focus is at 2.5 meters. Another interesting thing to consider is the placement of the rat's eyes, which are on either side of the head versus a human's eye placement in the front of the head. This creates a much larger field of vision and is an obvious benefit for a prey animal. Predators tend to have the forward facing eyes; they have a smaller field of vision, but a much more acute one. This also affects depth perception, and is another reason why those whiskers come in so handy for rats! But, there is another trick that rats can use to gain depth perception. This is called motion parallax. We've all probably seen our rats do this, especially those with lowered visual capability (i.e. albinos). They sway the head side to side in order to determine relative distance of objects. There is some orientation visually, but most is accompanied by use of the whiskers in touch as well.
As a side note, vision is also impaired with age, and older rats do have lower visual capacity than younger rats.
Albino rats require just a couple more comments. First of all, why are the eyes pink? Because there is no pigment in the iris at all, the color is coming from the capillaries and blood present in the eye. Also, because of an albino's inability to filter out light, degeneration of the retina occurs much more rapidly than in rats that have pigment. In fact, if a rat is in 24 hour light, the degeneration can occur in as little as a few weeks (yet another reason to be sure and offer normal cycles of light for our rats). In bright light, a pink eyed rat is virtually blinded. But, unfortunately due to poor rod development as well, even low light conditions are not going to create better vision. They also take longer to adapt to dark environments. Depth perception is poorer in albinos also and rely almost solely on their whiskers as the primary sensory system. And, one other interesting fact regarding the connection between what the eyes see and what the brain perceives. The albino's eyes are actually connected differently than a pigmented rat and it will have more difficulty processing and bringing together what the two eyes are seeing.

Touch...
The sense of touch via the whiskers and other sensitive hairs on the body of a rat is the major sensory system for navigation. Whiskers are on the rat's cheeks, chin, mouth, eyebrows, and even above the feet. They are more sensitive than a human's fingertips and allow the rat's surroundings to literally be 'seen' in sharp detail. Each individual whisker bends when it is touched, and those delicate movements are picked up by nerves that send detailed messages to the brain of the rat. The rat can even tell the direction and amount of movement in each seperate whisker at any given time. Rats have whiskers when they are born and within the first two weeks, they are whisking them back and forth like their adult counterparts. If a whisker is shed or lost, a new one will grow back in about a week, and until it is replaced, those around the lost whisker compensate for the loss. The brain is remarkable with how it can continue to function with the loss, however, if a rat has no whiskers, it's brain is actually abnormally wired and orientation within an environment is less efficient.
How do rats use their whiskers? The whiskers are constantly whisking back and forth (average of 7 times per second) to perceive their immediate surroundings. Slower sweeps and made while exploring and more rapid sweeps are typically seen when a rat is sitting still. Rats can even more whiskers individually and in opposite directions from one another. They can also point whiskers forward as far as 2 inches beyond their nose. They are truly remarkable features. Whiskers give a rat a three dimensional view of their close environment, down to detecting the difference in grains of sandpaper even! The whiskers resonate and vibrations even help the rats 'hear'. Whiskers are used for balance, orientation and depth perception. Amazingly, without whiskers, a rat in water would drown (please don't ask about the study that determined that one). The whiskers help the rat feel when the nose is above the surface of the water. Whiskers are used with contact as well and many aggressive rats that stand off to each other will maintain 'whisker' distance as a safety zone. All in all, a rat without whiskers is more impaired physically and behaviorally than a blind or deaf rat. So, what about rex rat whiskers, then? Rex coated rats have roughly half the whisker span that standard rats do, and in some areas like the top of the head, there can be an absence of functional whiskers all together, creating a 'blind spot'. A rat born with these shortened whiskers will adjust though, and are still able to 'feel' their environment in the same manner as a standard rat, but with obvious closer proximity, so it is limited. And rats with no whiskers are 'blind' to their world in a very unnatural way.

References:
http://www.spflrc.org/user/rats/perception.htm
http://www.spflrc.org/user/rats/rathearing.htm
http://www.lsu.edu/deafness/HearingRange.html
http://www-personal.umich.edu/~bclee/laughpapers.txt
http://www-personal.umich.edu/~bclee/ratdet.html
http://www.spflrc.org/user/rats/RatTaste.htm
http://www.spflrc.org/user/rats/RatOlfaction.htm
www.ratbehavior.org/Eyes.htm
www.ratbehavior.org/RatVision.htm
www.ratbehavior.org/RatWhiskers.htm

Hypochondriac's guide

Cove Rattery — Tue, 18 Mar 2008 02:40:07 GMT

So, I had decided to read a bit in another area of interest that is very close to home for me. Um, yeah, I'm one of those hypochondriacs and from what I've read so far, this book is a complete riot!

So, I love this book. It is feeding my insanity page by page. For instance, did you know that simple things can be symptoms of everything from tumors to cancer to heart attack to stroke to organ failure to death? I mean, we're talking hiccups, insomnia, ringing ears, sniffles, pins & needles, deja vu, yawning, bad breath, nosebleeds, snoring, toothaches, and on and on. Oh, and I don't mean ALL of these things are symptoms of bad things to come...I mean just a single thing can be pointing to doomsday! Frightening, isn't it?