Livestock Newsletter January/February 2000

Table of Contents
 

• Georgia Swine Inventory 1999
• Aquaculture Effluent Guidelines are Being Developed
• Soils for Construction of Catfish Ponds
• 2000 Tifton Beef Cattle Short Course
• What is Energy for the Horse?

 

Georgia Swine Inventory 1999

Tim Schell
Extension Specialist - Swine

According to the December USDA Hogs and Pigs report, Georgia lost another 300 swine producers during 1999. There were an estimated 1,700 hog producers in Georgia in 1998 and only 1,400 producers in 1999. Last year's loss represents an 18% decline in the number of operations in Georgia. The same number of operations were lost during 1998.

The sow numbers in Georgia also declined last year by 17%. The report showed an estimated 70,000 sows in Georgia during 1998 and only 60,000 sows during 1999.

However, the market hog estimates for Georgia were slightly up. Georgia marketed approximately 420,000 hogs during 1999, up 2% from 410,000 marketings during 1998. This increase in marketings may reflect a selling off of breeding stock and the exiting of producers from the market.

Nationally, the breeding inventory was down 7 percent from last year. The number of operations with hogs declined 14 percent last year, down to 98,460 operations. The report also showed that operations which own more than 50,000 head (105 operations) now account for 40 percent of the U.S. inventory. Furthermore, 32 percent of hogs in the U.S. are now raised under a contract of some type.

Breeding intentions through May 2000 are 4-5 percent below last year's farrowing levels. These reduced breeding intentions could translate into improved prices during 2000. However, estimates for prices through 2000 are in the upper $30's.

On another note, the USDA will no longer estimate Georgia or Kentucky hog numbers quarterly due to the decline in production in these states. Instead, Colorado and Texas quarterly numbers will be reported.
 
 



Aquaculture Effluent Guidelines are Being Developed

Gary J. Burtle
Animal and Dairy Science - Tifton, GA




New regulations for the Aquaculture Industry are on the horizon. We have expected this for years and the slow process is still evolving. Last year, the U.S. Environmental Protection Agency began a preliminary study of the Aquaculture Industry to evaluate the current wastewater controls and if there could be improvements made that would benefit the environment. As a result of that effort, the conclusions are that a standard set of guidelines will be developed for implementation on a national basis. These guidelines will effect the National Pollutant Discharge Elimination System (NPDES) permitting system. This effort is important to Georgians since our state policies regarding aquaculture effluents will change automatically when new U.S. EPA regulations are changed.
 

Background

Aquaculture facilities have been regulated under the NPDES permitting system but smaller facilities are exempt. Such exemptions include facilities that produce fewer than 100,000 pounds of warm water fish per year, closed ponds that discharge only during periods of excess runoff, cold water facilities that produce less than 20,000 pounds of fish per year, or cold water facilities that feed less than 5,000 pounds of food in any month. The original U.S. EPA guidelines were developed in 1974 and no effluent limitation guidelines or standards were issued. Since then, the Aquaculture Industry has gotten bigger and included about 5,000 facilities according to the 1997 agricultural census. The U.S. EPA has been under pressure to regulate aquaculture facilities by groups that include the Environmental Defense Fund (EDF). In the EDF report, "Murky Waters: the environmental effects of aquaculture on the United States," fish farms are cited for the nutrients the may contribute to natural waters. That report also concluded that some forms of fish culture are less polluting than others and that some pollution reduction technologies are being used on some fish farms.
 

What is the Concern?

EPA says that additional regulations are necessary due to "the current growth of the Aquaculture Industry." Changes in regulations will effect the "inconsistent state regulatory oversight" that fish farmers have at the current time. Although it seems natural that each state would have a somewhat different approach to regulations, EPA will examine these differences in order to develop the national guidelines. The new standards are intended to make the NPDES permitting program easier to administer by the states. Current technologies that are available for control of pollutants will be examined for application to aquaculture operations.
 

Who will EPA listen to?

In a recent news release, EPA says it will work with a number of stakeholder groups in the process of developing the new guidelines. It specifically mentions a newly created Aquaculture Effluent Task Force of the Federal Joint Subcommittee on Aquaculture (JSA). The JSA is an attempt to get representatives from USDA and other federal agencies together on national aquaculture issues. For more information on the aquaculture effluent guidelines contact Mike Clipper, U.S. EPA, Office of Water, Engineering and Analysis Division (4303), 401 M Street, SW, Washington, DC 20460 or visit the web page at http://www.epa.gov/OST/guide/. More information is promised by EPA as it develops these guidelines.
 
 



Soils for Construction of Catfish Ponds

Gary J. Burtle
Animal and Dairy Science - Tifton, GA




Recent interest in catfish pond construction is occurring across Georgia in the area south of the fall line. That area has relatively large volumes of groundwater and a coastal plain topography. However, the soils can be quite variable in quality for pond construction. Soils may change classification due to changes in the depth of topsoil, sand, clay, and silt content, or slope. Since pond construction requires the presence of a certain amount of clay in the soil, it is important to know where the changes in clay content occur on each site.
 

Ideal Soils for Pond Construction

Soils for pond levee construction should have between 25 and 60 percent clay, less than 70 percent sand, and enough silt to fill the spaces between the clay and sand. Too much clay can allow fractures to form if levees are allowed to dry. Too little clay will allow water to seep from the pond. Soils of different clay contents can be mixed together to end up with a clay content in the desired range. It is most economical to build ponds where suitable clay is at or near the soil surface. Many Georgia soils have clay located 12 to 24 inches below the surface.

In those soils, a keyway can be dug into the clay layer so that compacted clay can be laid from a point below the clay layer surface to the top of the core. Dig the keyway a minimum of 36 inches below the point where the soil contains 25 percent clay. The core should be 8 feet wide. Clay compaction should be continuous or at least every 12 inches of fill. Utilizing dirt pans or scrapers will help compaction, but when bulldozers are used, a sheeps foot roller should be used for compaction of the core. In order to aid compaction, a soil moisture content of 10 to 15 percent is desirable.

Each site must be evaluated for the depth to suitable clay, the distance to haul clay to fill the keyway and core, and the cost of digging the keyway. In most cases, a depth to clay of 36 inches or more makes catfish pond construction impractical. The slope of the soil should be less than 5% but the soil should be well drained and not classified as a wetland. Pond construction costs increase with the amount of timber or brush clearing required.
 

What to do with the Top Soil

Top soil must be removed from under the levee, but top soil within the pond need not be removed. All vegetation should be removed, including roots, from within the pond. As long as the core ties into the clay layer, top soil within the pond can be tolerated. All pond bottoms should be graded to as smooth a grade as possible if commercial catfish production is anticipated. All commercial catfish ponds should be drainable. Therefore, the pond bottom should be higher than the down slope elevations of the site. The pond drain should be located at the proper elevation before soil is removed from the inside of the pond. No catch basin or pit should be constructed within the pond. An even 0.5% slope of the pond bottom is ideal.
 

Pond Construction Assistance

The University of Georgia Cooperative Extension Service can help with site location and pond construction information through your local county agent. Soil surveys are available at each county office of the Natural Resources Conservation Service. The pond owner is usually responsible for taking soil cores and obtaining pond construction surveys. Although generally available in the past, few NRCS offices in Georgia provide pond site surveys today. For land owners who wish to design their own ponds, software is available to input survey information for pond planning. AquaCAD Pond Design Software is a program that allows calculation of cut and fill volumes for pond construction, available from David Bader at 318-281-7397, 1058 Cooperlake Road, Bastrop, LA 71220. Levee is a program offered by the Mississippi Cooperative Extension Service, Computer Applications & Services Department, Mississippi State University, Mississippi State, MS 39762 for calculation of pond levee volumes. Each program requires data on the elevations of the existing topography.
 

Common soils in for pond construction in south Georgia.
Soil Type	Depth (inches)	Permeability	% Clay
Ar A  Ardilla	0-12 12-35	2.0-6.0 0.6-2.0	4-17 18-35
Do A, B Dothan	0-12 12-35	2.0-6.0 0.6-2.0	4-17 18-35
Fe A, B Faceville	0-7 7-12	6-20 0.6-2.0	5-20 20-36
Gr Grady	0-10 10-17	0.6-2.0 0.2-0.6	15-30 20-35
Gs A Greenville	0-8 8-72	0.6-6.0 0.6-2.0	5-20 35-55
Na B Nankin	0-8 8-31	2.0-6.0 0.2-0.6	5-12 35-50
0r A Orangeburg	0-8 8-12	2.0-6.0 2.0-6.0	4-10 7-18
Ra Rains	0-15 12-48	2.0-20 0.6-2.0	2-20 18-35
Tf A, B Tifton	0-10 10-42	6.0-20 0.6-2.0	3-8 20-35


 

2000 Tifton Beef Cattle Short Course

Tuesday, February 29, 2000
Tifton Bull Evaluation Center


 




PROGRAM	PROGRAM PARTICIPANTS
Morning Session
Presiding .....................................................Jerry Baker	Dr. Jerry Baker, Animal Science Location Coordinator, Tifton Campus, The University of Georgia, Tifton, GA
8:30 AM   Registration	Dr. Rick Hardin, Beef Nutritionist, Moorman's Inc., Monroe, GA
9:00         Georgia Beef Challenge Update, Bobby Lovett                     & Robert L. Stewart	Dr. Larry Hawkins, Assoc. Professor of Production Medicine -- Emphasis on Beef Cattle, The Univ. Of Georgia Vet School, Athens, GA
9:30         Heifer Evaluation & Reproductive Development                      (HERD) Program, Lynn Youngblood	Mr. Bobby Lovett, Cattleman, Cuthbert, GA
10:00        Break	Dr. John C. McKissick, Extension Economist-Livestock,  The University of Georgia, Athens, GA
10:15        First Nursing - The Start of a Health Program	Dr. Mel Pence, Veterinary Field Investigator, The University of Georgia, Tifton, GA
10:45        Biosecurity - BVD	Dr. Robert Stewart, Extension Animal Scientist, The University of Georgia, Tifton, GA
11:30        Vision for the Cattle Market Future,                     John C. McKissick	Dr. Rhonda Vann, Post Doc Research Associate, Animal & Dairy Science Dept., Tifton, GA
12:15     Lunch	Miss Lynn Youngblood, Turner County Extension Agent, Ashburn, GA
	The location is 12.5 miles east of I-75 (exit 26) and 1.5 miles west of Irwinville on Georgia Highway 32.
Afternoon Session
Presiding .................................................Robert L. Stewart	MAKE PLANS TO STAY OVER FOR THE TIFTON PERFORMANCE TESTED BULL SALE ON MARCH 1.
1:30          Reproductive Scores & Their Relationship to Puberty                     Mel Pence & Larry Hawkins
2:30          Effective Synchronization of Females, Rick Hardin
3:00          Scenarios with Bulls & EPD's
3:45          Adjourn and view bulls
The University System of Georgia offers educational programs,  assistance and materials to all persons without regard to race,  color, national origin, age, sex or handicap status. AN EQUAL OPPORTUNITY EMPLOYER


 

REGISTRATION -- 2000 TIFTON BEEF CATTLE SHORT COURSE




Pre-Registration Fee (by Feb. 18): $5.00 Late Registration Fee: $10.00

County Extension Agents, Vo-Ag Teachers, and Students -- Free if pre-registered.

FEE: No. of People @ $ Each Total Paid

NAME:

MAILING ADDRESS

CITY STATE ZIP

COUNTY DAY PHONE NIGHT PHONE

Make checks payable to: BEEF CATTLE SHORT COURSE.

Mail to: Robert Stewart, P. O. Box 1209, Tifton, GA 31793.
 
 



What is Energy for the Horse?

Gary L. Heusner
Extension Equine Specialist




Many horse owners have a difficult time understanding energy requirements for the horse. In part, this is due to the fact that the concept of energy as a single nutrient for the horse is difficult. Energy is one of the five nutrients required by the horse along with water, protein, minerals and vitamins. Energy is required in the horse for muscle contraction, digestion and absorption of nutrients, as well as for synthesis of new chemical compounds in the body such as tissues and hormones. Energy is needed on a continual basis for the maintenance of all of the body's everyday normal functions. This is referred to as "maintenance" energy requirements and also "basal metabolic" requirements. Maintenance energy requirements can also be thought of as the amount of energy required by a horse to maintain its body weight (not losing or gaining) when the horse is not doing any work, lactating, gestating, breeding, etc. Maintenance requirements are typically 60-70% of a horse's daily energy requirements when they fall into one of the above categories. Table 1 lists the maintenance energy requirements for various weights of horses. The chief source of energy in a horse's diet is carbohydrates.
 

Table 1. Maintenance energy requirements (megacalories of digestible energy per day) for horses of various mature weights.
Mature Body Weight (lbs)	Mcal/day Maintenance
850 900 1000 1100 1200 1300 1400 1500	13.0 13.6 15.0 16.4 17.7 19.1 20.1 20.9

Carbohydrates come from the digestion of forages (grass and hay) by microbes in the hind gut of the horse. The carbohydrates from forages are converted by the microbes to volatile fatty acids and absorbed into the bloodstream and used or stored as energy. Carbohydrates from grains (starches) are mostly digested by enzymes in the small intestine as well as absorbed from the small intestine. Carbohydrates are stored as glycogen which is a number of glucose molecules formed in a chain. Glycogen is stored in the muscle and liver. Fat is another source of energy that has been used in horse diets. Fat comes from either animal or vegetable fat or a mixture of both. Fat is digested and absorbed in the small intestine and stored in fat tissue. The average horse's body fat is 7-8% of the horse's body weight. Both carbohydrates and fats contain the elements carbon, hydrogen, and oxygen (CHO). Protein can be used as a source of energy but using protein is very energy inefficient. Proteins contain carbon, hydrogen, oxygen, and nitrogen (CHON). The inefficiency of protein utilization is that the nitrogen must be removed and excreted via urine. Thus energy is required to get rid of the excess nitrogen. What is the energy measure for carbohydrates and fats or more importantly what are the energy values of various feedstuffs commonly fed to horses? As shown in table one energy requirements for the horse are expressed in Megacalories of Digestible Energy. By definition, one calorie is the amount of energy required to raise the temperature of one gram of water by 1.8F. Each gram of pure carbohydrate (glucose or glycogen) contains 4 kilocalories (4,000 calories) and each gram of pure fat contains 9 kilocalories. Digestible energy is measured by measuring the gross energy that goes into a horse and subtracting the energy remaining in feces. In other words if the digestible energy for a particular feed needs to be determined, the total amount fed is measured and a sample is taken for gross energy analysis. The horse is fed this diet for three to five days. All the feces are collected and weighed during this time period and the energy content of the feces is determined. Therefore, digestible energy is feed energy - fecal energy. Table two lists some common digestible energy values for various feedstuffs. Table three gives more defined values for hays based upon the quality of hay. One of the problems in using digestible energy values for feeds is that commercially prepared feeds do not give digestible energy values on the feed tag. The value that correlates to energy level is the Percent Crude Fiber. Table four lists the crude fiber levels of commercial feeds and the approximate corresponding digestible energy content of the feed. These values will not apply if fat has been added to the feed or as shown by the table if the crude fiber content of the feed is above 10%. An important concept in feeding a horse properly is to base other nutrient levels on the energy intake. A properly balanced diet will take into account the amount of energy a horse is consuming per day as well as protein and make sure that the protein/calorie ratio is in a specified range. This is particularly important for young growing horses. A properly balanced horse diet will also meet specific calcium/calorie, and phosphorus/calorie ratios as well. In other words digestible energy intake will determine the levels of other nutrients in a balanced horse ration.
 
 
 

Table 2. Digestible energy values of various horse feedstuffs.
Feedstuff	Digestible Energy Mcals/pound
Alfalfa hay Bermudagrass hay Beet pulp Oats Corn Molasses Vegetable oil/fat	1.10 0.80 1.00 1.36 1.56 1.18 4.00


 
 

Table 3. Approximate digestible energy values of hays for horses based on crude protein, neutral detergent fiber, and crude fiber values. (100% Dry Matter Basis)
Hay	Crude Protein %	Neutral Detergent Fiber %	Crude Fiber %	Digestible Energy Mca/lb
Alfalfa	>20	<30	<23	1.2
Alfalfa	16-18	30 - 47	24 - 28	1.1
Alfalfa	<15	>47	>28	1.0
Bermudagrass	>12	<65	<30	0.9
Bermudagrass	8-12	66 - 72	31 - 35	0.8
Bermudagrass	<7	>72	>35	0.7
Bahiagrass	>9.5	<68	<32	0.75
Bahiagrass	7 - 9.5	68 - 75	32 - 36	0.7
Bahiagrass	<7	>76	>36	0.6
Fescue	>12	<65	<26	0.95
Fescue	7 - 12	66 - 70	27 - 30	0.83
Fescue	<7	>70	>30	0.75


 

Table 4. Approximate digestible energy values of mixed concentrate feeds based upon crude fiber values
Digestible Energy
Crude Fiber	Kcal/lb	Mcal/lb
2.0 3.0 4.0 5.0 6.0 7.0 8.0 9.0 10.0	1600 1500 1420 1400 1370 1350 1330 1300 1250	1.60 1.50 1.42 1.40 1.37 1.35 1.33 1.30 1.25

In summary, energy is the fuel that makes the horse able to function. Energy utilization by the horse is a complex series of biochemical reactions starting with ingestion of feedstuffs that provide energy chiefly in the form of carbohydrates and possibly added fat. The energy requirements for various weights of horses are based on maintenance and then whatever activity they may be involved in. A balanced horse ration attempts to maintain certain nutrient:calorie ratios to prevent any metabolic disturbances.