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Wednesday, October 26, 2011

Calving (parturition) 10/24&26

Parturition - the process of giving birth
3 stages - Preparatory, Birthing, Placenta

Some signs of impending parturition
Distended stomach
Mammary (udders) begin to fill with milk

Anorexia

Swollen Vulva
Restlessness
Separation from the herd












Stage 1 - Dilation of the cervix begins, Rhythmic uterine contractions, the calf will rotate to the upright position, then the water sac is expelled.


Stage 2 begins with increased rate of contractions with abdominal pressing. the calf and placentas are pushed through the vagina. The proper presentation of the calf is forelegs first with the nose resting on the legs. 
Most cows calve at night (mostly to piss us off when we spend hours looking for them in zero degree weather) due to the inherited instinct that they can hide the newborns from predators better at night. One way to influence the calving time to better suit us is the Konafel Method
Feed from 11-noon and 930-11pm to cause cows to calve during the day. start about 1 month ahead of first due date. this method varies from 10% effectiveness to 80% effectiveness.

To induce a cow into labor - do not do before last 7-14 days of the gestation period.
use Dexamethasone- calving will occur in approx. 48 hours. 20-50mg/IM
Inducing causes a high incidence of retained placentas and lowers post partum fertility.
Azium mixed with 25mg of Lut will also induce a cow in 35 hours.
Induce sheep with 8-20 mg of Dex , 24-72 hours, no retained placenta.

Birthing times for cattle (normal)
heifers - 1-3 hours post water sac
cows 1-2 hours post water sac

Stage 3 - Placenta expulsion- The uterine contractions push the placenta out usually within 12 hours in cattle nd 8 - 24 hours in ewes.

Dystocia/Calving problems
Causes : High birth weights and most importantly calf shape (broad shouldered, big boned)
Presentation problems (breech, head back, legs tucked)
or Multiple Births.
10% in cows and a higher rate in heifers

Factors affecting calf size - High levels of feed and protein intake by the cow, selection of growth rate in the sire leads to a high correlation with birth weights. The breed of the dam and sire are also factors. The sire determines the gestation length usually. Age of dam, heifers average 8lb lighter calves. and finally, the size of the pelvic opening.  
The King Of Dystocia
Heat Wave
After a delay in delivery, you should conduct a pelvic examination while wearing an OB sleeve.
Determine the position of the fetus
Examine size of the calf relative to the birth canal
Then attach a pulling device (I prefer a soft rope, but most use chains)


Cesarian Section - Occurs when the calf is simply to big to go through the birth canal or is in an unmanipulative position. First the area is shaved and sanitized then anesthesia is administered 
Fetalectomy - Surgical extraction through the vagina, if the calf is too large and already dead (this is where the calve is cutup inside and pulled out, piece by piece)

Retained Placenta - failure to expel placenta, wait 48 hours then give injectible antibiotics with a uterine bolus. If placenta doesn't come out, you can pull it out, but be gentle.

Uterine Prolapse 
the uterus comes out thought the vagina, inverted. caused by a difficult birth and too much traction, subclinical milk fever and should be treated as an emergency .

Newborn calf care - look for normal respiration, free airway of mucus and phlegm. roll the calf onto sternum as this allows the calf to breathe easier. Dry and rub the calf vigorously to stimulate circulation. Dip the naval in Iodine to prevent a disease called naval ill.

Monitor colostrum intake - colostrum is the first milk the calf gets from the mother, it contains all the antibodies and nutrients to kickstart the calfs immune system. Studies show that calves who never get colostrum do poorly through life. after 24 hours, gut closure occurs and the immunglobins can't be absorbed. this is crucial. calves should receive 10% of their body weight in colostrum milk in first 24 hours.






Friday, October 21, 2011

HHEEEEYYYY

its nice to know some people actually do read this thing who are in the same class. Tell your friends and their friends too.

Monday, October 17, 2011

Embryo Development

Capacitation  in cattle takes roughly 6 hours, while ovulation in cattle occurs 25-32 hours after the onset of standing heat.
Semen sexing - sex is determined by an X(female) and Y(male) chromosomes in sperm cells. A FACS machine is used to determine and separate the individual sperm based on their chromosome. They actually look at each individual sperm at a time.

Gestation Management 
Day 1- Fertilization of sperm and egg, happens in the oviduct (fallopian tubes), immediately after fertilization, cell division begins.
Different stages of development (zygote, marula, blastacyt, embryo)

Days 2-5 - Zygote passes down the oviduct and enters the uterus by day 5 post breeding.

Day 6 - Cell differentiation - different organ and tissue cells begin developing.
Ectoderm - Skin, Nervous System - External Layer
Endoderm - Lungs, thyroid, pancreatic - inner layer
Mesoderm - Muscle, skeletal system - middle layer

Maternal Recognition of Pregnancy 
recognition of pregnancy doesn't involve any conscious recognition by the mother, rather a chemical hormonal signal. The window for recognition is very narrow.

Interferon Tau is the hormone that signals a pregnancy. In sheep, (ovine) interferon  tau is released around day 12-13 and in cattle (bovine) interferon tau is released in days 15-16.

Int. Tau inhibits the production of pgf2a (prostaglandin, which destroys the CL [corpus luteum] that maintains pregnancy) no prostaglandin means a safe CL which means a stable pregnancy.

In humans - the fetus produces chorionic gonadatropin hCG - similar to LH, it binds LH receptors on the CL and stimulates progesterone production. Pregnancy tests look for hCG.

Day 14 - Embryo elongation - the embryo helps to establish its own room or space in the uterus, especially in hogs and sheep because of the multiple embryos, by elongating the cells inside.

Day 30-35 - implantation and attachment - the embryo attaches itself to the uterine wall and can now receive nutrients directly from the mother. Before implantation, the embryo had to receive nutrients from the uterine fluids.

The First Trimester - most differentiation happens while the 2nd and 3rd trimester experience mainly growth.

Fetal Growth
Bone development - day 70
Extensive Bone Development - 180
Teeth - 110
Hair, eyes, muzzle - 150
Hair on the entire body - 230
More than 50% f fetal weight comes in the last 2 months of pregnancy

Pregnancy Detection
There are several methods to detect a pregnancy in cattle. Detecting pregnancy is essential to main a productive cow herd, as it costs money every day to feed and maintain them. Non-Productive days = days when a cow isn't raising  calf or is pregnant.
Estrus detection - Cheap, easy, fairly accurate, and quick. Sometimes though, cows can display a false heat.
Rectal Palpation - most common, can be performed around day 45 of pregnancy. The vet or other person is feeling around the uterus for the fetus its self or later on can feel the weight in the uterus. Sometimes its not always accurate and can also cause abortions, not to mention it can be expensive.
Ultrasound - Detects the developing embryo as early as 25 days, extremely accurate, but the ultrasound machines are expensive.
Blood/Milk Progesterone Test - Measure the level of progesterone in in either the milk or progesterone, must be performed between 18-21 days. accuracy = 61-88 %
BioPryn - Blood pregnancy test - tests for a protein called Pregnancy Specific Protein B (PSPB) which is produced by the placenta. Can be used as early as 28 days post breeding, 90 days post calving. 99% Accurate, costs $2.40 per sample + supplies.

Wednesday, October 12, 2011

Artificial Insemination Basics and Estrus 10/12

Today we covered mostly things about AI. pretty basic for us show calf producers but you wouldn't believe the amount of farm kids who didn't have a clue about breeding a cow, heat detecting, semen freezing...

Semen standards for Rams
percent motility - 30% - 70%
percent normal morphology - 30%-50%
White blood cells >5
Brucella Ovis  - Negative

10-15 % of Rams fail a BSE

Male : Female ratio for breeding
18-1 for yearling bulls (1 bull for 18 cows)
30-1 for mature bulls
35to 50 - 1 mature rams
15-30 for ram lambs

Synchronized matings 1:5 or 1:10 (sheep)

Estrous Synchronization
Why synch cattle?
1. With AI, decrease time and expense of time & labor for detection of estrus
2. Success of Embryo Transfer , especially with fresh eggs. Recips have to be in the same exact level of estrus as the donor cow for fresh, non frozen implants.
3. Uniform groups of calves, calving in the same time frame. Groups of uniform animals bring higher prices at the sale and its a hell of a lot easier/less worrisome to calve in a 3 week window vs a 3 month window.
4. Labor Savings - calving can be strenuous and a pain in the ass, but its easier to make it last a shorter time vs. a longer drawn out time.

Methods of Synchronization 
1. Natural method - weaning will cause the estrous cycle to start (especially true in sows)
2. hormonal - induce or suppress estrus (Lutalyse(prostaglandin) and CIDR's)

CIDR - controlled internal drug release - suppresses estrus with progesterone, progesterone maintains a pregnancy, so if she thinks she's bred, she won't come into heat right? Once progesterone levels drop (after the CL is killed, estrogen levels come up and result in a standing heat)

Why is AI used?
1. Maximize genetic improvement. - we can use virtually any bull in the world today for a small cost and can dramatically improve the herd with ease. a $20 straw of semen cost less than a big money bull + feed + transportation + vet bills.
2. Control reproductive diseases. All bulls collected are tested for leptospirosis.
3. The use of dead or injured sires. We can use bulls from 50 years ago thanks to freezing semen. there is always semen to be had on an old bull who is still popular today (Meyer 734 for example)

Keys to Success with AI
The detection of estrus is essential to having a successful AI program. can be detected with behavioral changes and of course, standing to be bred.
2. Proper timing of insemination, having viable sperm at the time of ovulation so the sperm is alive and ready to make some babies. Breed towards the end of estrus (8-12 hours afar standing, or use the AM/PM rule)
3. Technician Skill - conception rates depend heavily on the guy putting the semen in. for instance, if he's breeding through the rectum.... he might not be the right guy for the job. the cervix is the hardest part and some techs are better at getting through it than others.

Estrus Detection
Primary Characteristic of Estrus - Standing heat. 
Secondary Characteristic of Estrus - Restlessness, chin resting, bellowing, red swollen vulva, discharge from the rear, flehman response  from bulls (lip curl) fighting, riding other cows, less feed intake. Theres quite a few ways to detect estrus even if no standing heat is observed.

most breeding mounts occur between 7pm and 7am, so check right at dark and first light.

Sunday, October 9, 2011

Female Reproductive System ... from 10/7

First off, all hormone systems are the same as bulls, so reference that for the beginnings of the female system.
FSH goes to the ovaries, where it stimulates the follicle to become larger, and as it matures, it produces estrogen.
Infundibulum surrounds the ovary, catches the egg, and guides it to the oviduct.
LH (Lut) causes ovulation.
Corpus Luteum - forms where the follicle breaks open (to release the egg) . Produces Progesterone which protects the pregnancy.

ovary_l.jpg
images

Cysterella = GnRH
Lutalyse = Prostaglandin

Lut kills the Corpus Luteum, which in turn, will terminate the pregnancy.


Superovulation - excess FSH is given to produce multiple follicles to in turn, produce more eggs (for flushing)

oviduct - transports the egg and sperm to the site of fertilization, transferred by cilia
Uterus - transports the sperm from the cervix to oviduct, site of embryo implantation, where the calf develops... produces prostaglandin

Vagina and vulva... we know what those are.

Hormones
Estrus - in standing heat, willing to be bred. Due to increased concentrations of estrogen
Estrous Cycle - period of time from one estrus to the next , average of 21 days for cows, 17 for ewes

estrus period - cow 12-18 hours, ewe 24-36 hours

Axis.jpg
http://beef.unl.edu/learning/estrous.shtml

Reproductive Systems! ...from 10/5

I'm skipping over the sheep breeds lecture notes...

Male Reproductive System
GnRH Gonadotropin-releasing hormone (GnRH), also known as Luteinizing-hormone-releasing hormone (LHRH) and luliberin, is a tropic peptide hormone responsible for the release of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) from the anterior pituitary. GnRH is synthesized and released from neurons within the hypothalamus. The peptide belongs to gonadotropin-releasing hormone family.


starts in the hypothalamus, goes to pituitary gland and releases FSH and LH.


Luteinizing hormone (LH, also known as lutropin[1]) is a hormone produced by the anterior pituitary gland. In females, an acute rise of LH called the LH surge triggers ovulation[2] and development of the corpus luteum. In males, where LH had also been called interstitial cell-stimulating hormone (ICSH),[3] it stimulates Leydig cell production of testosterone.[4] It acts synergistically with FSH.


Follicle-stimulating hormone (FSH) is a hormone found in humans and other animals. It is synthesized and secreted by gonadotrophs of the anterior pituitary gland. FSH regulates the development, growth, pubertal maturation, and reproductive processes of the body. FSH andLuteinizing hormone (LH) act synergistically in reproduction.



Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles,[1]birds,[2] and other vertebrates. In mammals, testosterone is primarily secreted in the testes ofmales and the ovaries of females, although small amounts are also secreted by the adrenal glands. It is the principal male sex hormone and an anabolic steroid.
]
In men, testosterone plays a key role in the development of male reproductive tissues such as thetestis and prostate as well as promoting secondary sexual characteristics such as increasedmusclebone mass and the growth of body-hair.[3] In addition, testosterone is essential for health and well-being[4] as well as the prevention of osteoporosis.[5]
Testosterone is observed in most vertebrates. Fish make a slightly different form called 11-ketotestosterone.[7] Its counterpart in insects is ecdysone.[8] These ubiquitous steroids suggest that sex hormones have an ancient evolutionary history.[9]
Leydig cells, also known as interstitial cells of Leydig, are found adjacent to the seminiferous tubules in the testicle. They produce testosterone in the presence of luteinizing hormone (LH). Leydig cells are polyhedral in shape, display a large prominent nucleus, an eosinophiliccytoplasm and numerous lipid-filled vesicles. They are responsible for sperm production, semifonius tubules, spermatogenia .

Testosterone Aids in muscle building and LIBIDO (sex drive)



Oxytocin is best known for its roles in female reproduction. It is released in large amounts 1) after distension of the cervix and uterus during labor, and 2) after stimulation of the nipples, facilitating birth and breastfeeding. Recent studies have begun to investigate oxytocin's role in various behaviors, including orgasm, social recognition, pair bondinganxiety, and maternal behaviors.[2] For this reason, it is sometimes referred to as the "love hormone".[3]


oxytocin causes contractions in smooth muscle in the scrotum, causing ejaculation.


Epidymis - where the sperm matures, takes 45-50 days, 7 days in the epidymis


Vas deferens - transports sperm from testes during ejaculation, connects to urethra


ACCESSORY SEX ORGANS
Seminal Vesical
prostate gland
bulbourethral (Cowpers) gland


functions of ASO
Add fluid volume, nutrients, and alkaline buffers to semen
sperm plus ASO fluid = SEMEN


Carrier proteins - Albumin - protects the sperm


Anti-biotics are put into semen extenders to protect the sperm, cows, and offspring from common breeding diseases like Leptospirosis 


PENIS
the bulls penis is fibroelastic, and is a sigmoid flexure type (S shaped) it extends upon erection , allowing forextension. found in boars, bulls, and rams.
g02016art01.jpg

ejaculation
Bulls - 5ml - 1.1billion per ml. - low volume, high concentration

the head of the sperm carries genetic info
Aerosome, contacts egg and releases chemicals to dissolve the jelly coat around egg.
The tail pushes the sperm into the egg. it does NOT "swim all the way there"

Bulls reach sexual maturity at 12 months or a 26cm Scrotal Circumference



Beef Breeds... from 9/28

There are over 250 beef breeds recognized in the world. 80 in the US

Most Annual Registrations
Angus 283,000
Herfs
Limis
Chars
Simmis
Red Angus
Beefmaster
Gelbs
Brangus
Shorties
Brahmas
Santa Gerts

Angus
http://foodenator.com/wp-content/uploads/2009/05/aberdeen20angus1.bmp
Black and Polled, most popular in the US, used for good mothering skills and meat production.

Herefords - imported in 1742 - Easy keeping and longevity - more moderate frame and high marbling - 250px-Hereford_bull_large.jpg

Limousin - French - imported 1969 via canada - very meaty, awesome growth rate and yield.
Limousin.jpg

Charolais - French - imported via mexico from King Ranch - Large frame, heavy muscled, fast growth rate and high yield - some calving difficulties.

for More extended information on breeds, visit Cattle.com
http://www.cattle.com/articles/cat/Beef+Cattle+Breeds.aspx

Lets talk about sheep...from 9/28

Top Countries in # of sheep
China 127 Million (also tops in pork too)
Australia 120m
India 58m
Iran 53m
New Zealand 46m

USA 5.5m

Top states in sheep production
Texas 900k
California 650k
Wyoming 500k
Colorado 425k
Utah 300k

Ohio 85k


Sheep numbers are on the decline. There is no demand for the meat anymore and no more wool subsidies has caused a fleece to be worth next to nothing. At one point in time, Sheep numbers in the US towered much higher then cattle. The production has declined while imports are up and prices are up.

I should have mentioned this earlier but this class is primarily focused on Beef Production, but we do talk about sheep once in awhile

Industry Overviews 9/23

Top Countries for # of cattle.
India - 215m
Brazil - 159m
China - 107m
USA - 98m
Argentina - 55m

Top Countries for Meat Production
USA - 26 Billion lbs
Brazil - 13b
China - 10b
Argentina - 6b
Russia - 5b

How can we have significantly less cattle than Brazil and still double their production? (India doesn't slaughter cattle, I'm sure you knew that)
Answer - our genetics are better. We have been using feed efficient, fast growing, and high yielding cattle for years. Bos Indicus (indian cattle) are also dominant in Brazil, these cattle take a lot longer to finish out then an Angus cross. They also are primarily grass fed in Brazil. We feed grain to our  cattle which is obviously faster at finishing an animal out. Quite simply, the USA is where the beef is at.

Top States for Beef Cows
Texas 5.1 million
Oklahoma 2m
Missouri 1.9m
Nebraska 1.8m
South Dakota 1.6m

for comparison, Ohio has approx. 297k head of cattle.

Cattle on Feed
Texas 2.7 million
Nebraska 2.5m
Kansas 2.4m
Iowa 1.4m
Colorado 1m

Feedlots are in the midwest because its dry. a feedlot is a piece of ground with feed bunkers, what happens if you put 20,000 cattle in a dirt lot and it rains? EPIC MUDHOLE.

Largest Feeders
1.JBS Swift, also the largest packer, Brazilian based. 870k capacity.
2.Cactus
3.Cargill

Top Packers
JBS Swift (they dominate the market because of vertical integration)
Cargill
Tyson
NBPC
American Foods

Top 10 importers of American Beef
Japan (money, the best quality, they get the good cuts of meat because they will shell out the big cash for it)
Mexico (low quality)
South Korea
Canada
Hong Kong

Who gets the best and worst cuts of meat (1 being the best and 6 being the worst)
1. Exports (places like japan who have the money to afford top quality meat)
2. Fancy restaurants
3. Food services (caterers and banquets)
4. Regular restaurant
5. Grocery Stores
6. Exports to poor countries

In the USA we export what we don't want (or what other countries are willing to pay for) (things like tongues , stomachs, tails.
we import things we like, steaks, burger, etc etc.

Factors affecting development of the industry in the US 9/23

Population growth in the United States.
Climate. Hot, dry conditions, the midwest, is ideal for producing cattle in feedlots and pastures. extreme wetness or extreme heat are not ideal for raising cattle, so areas like Oklahoma and northern texas are the best locations.
Land.
Transportation.

In 1803, we made the Louisiana purchase which allowed the nation to expand westward.
1820 - Ohio and Erie Canals allow for boats carrying cattle to move faster to their destinations.
In this day there was a lack of preservatives, which only allowed live cattle to be shipped.

primary transportation in the day was boats and train wagons.

Trains - 1830. Allowed for faster shipping of live cattle. in 1869 the trans continental railroad was completed. This pretty much destroyed the canal system as it was faster and cheaper.
6% death rate for live cattle in the carts, 9% for sheep.

In 1867 barbed wire replaced Osage Orange Brush as fencing. This allowed ranchers to raise cattle in a fenced area and also settled land territories. this caused major conflicts in the 80's for those who still drove cattle (cattle can't pass if a fence is in the way)
Refrigerated rail carts allowed for more product (meat) to be shipped to the buyers which helped boost efficiency and allowed for profit on cattle

Union Stockyards (1865-1970) - largest packer in the nation, located in Chicago, all cattle were shipped here then the product was shipped by railways to the distributors.

"the jungle" is based off Upton Sinclair's visit to the plant. it describes the terrible working conditions faced and revolutionized workers rights.

Union stockyards was killed by shipping costs. Now the packers are located closer to the cattle in the midwest, so the cost of shipping live cattle was drastically cut.

and eventually Trucks replaced railways, because shipping is faster.

Some issues affecting the beef industry today : Government, drought, Issue 2, HSUS, Gas Prices, and Food Safety.

Packers moved to the midwest (closer to the cattle)

Beef History 9/21

My first class is Beef and Sheep production so these posts are primarily cattle based.
Cattle are derived from the Auroch (ancient ancestor) from India. they stood 6.5 ft at the shoulder and inhabited Europe/asia/africa. they were domesticated 6-8k years ago in Europe/asia.

There are two types of cattle, Bos Indicus and Bos Taurus. Bos Taurus are of euro decent and are humpless (herefords, angus etc etc). Bos Indicus are derived from India and have humps (brahma)

Shorthorns are one of the oldest recognized breed (1500's, imported to the US in 1783)
Columbus introduced cattle in 1493 to the western hemisphere. Hernando  Cortez was the first to bring cattle to north america (1519). At this time cattle were only used for milk production.

Longhorns - Hardy, adaptable, self sustaining cattle. The longhorn era ended when the open range was fenced. They calved unassisted for hundreds of years. (natural selection at its finest, in the calving department)

Henry Clay imported herfords in 1817. Almost all herfords in the US date back to Anxiety 4, a bull used in 1881.
George Grant imported the first angus from Scotland. he brought four head to Victoria, Kansas. Eventually they were commonly crossed with Longhorns.

Breed - A group of related cattle that share similar characteristics


again these are just notes I've taken as I've wrote them. At this point its very easy if you come from a cattle background.

Welcome.

This blog will serve as a journal not only for my self, but people also interested in Animal Science. I'll be posting all of my notes and thoughts in this blog. Feel free to ask anything or comment on anything.  Ill start off by posting what I've accumulated to this point.