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Page 1: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

PB 1664

Page 2: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

page

3 Why Castrate?

3 When to Castrate

3 Restraint

4 Anatomy

4 Examining the Scrotum

4 Surgical Castration

5 Equipment

5 Opening the Scrotum

5 Removing the Testicles

6 Wound Treatment

6 Other Castration Methods

7 Safety

7 Summary

Page 3: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

Castration is removal of thetesticles of a male animal. Castra-tion of your bull calves is an easyprocedure to perform. Severaltechniques can be used and allcan be mastered by the cattleproducer. Feeder steers sell formore than bulls and the differencewill pay for the costs associatedwith the practice several timesover. Based on Tennessee live-stock auction market reports,500-pound steer calves sell for$25 more per head than bulls ofcomparable quality. All maleTennessee feeder calves shouldbe sold as steers.

There are several goodreasons for castrating bull calves.Steers are less aggressive in thefeedlot than bulls and are lesslikely to injure one another. Also,steers can be grouped with heiferswithout any danger of unwantedpregnancy in the heifers. How-ever, the best reason for castrat-ing bull calves is the increasedvalue of the calf. Processorsprefer steers over bulls, becauseat typical slaughter ages, steershave higher meat quality. Steersmay grow a little slower thanbulls, but the difference can bemade up by implanting the steercalves with a growth promotant atthe time of castration.

Castration of calves can bedone at any age. Purebred produc-ers often wait until after weaningto decide which bull calves tocastrate. However, in most com-mercial cow-calf operations, theearlier in the calf’s life the job isdone, the better. A young calfseems to experience less discom-fort as a result of castration thanan older one. Younger calves areeasier to handle and restrain thanolder, larger ones. Finally, thebleeding, infection and weightgain depression associated withcastration are less in youngercalves. Baby calves are easy tocatch and handle for the first 36hours of life and this is an idealtime for castration. Some produc-ers prefer to wait and castratecalves in groups. This is accept-able as long as all calves arecastrated at less than 3 months ofage. Avoid castration during thehot, summer months due to flyproblems and resulting infections.Castrating on cold, wet days maynot be a good idea. The calf maylie down in mud and pick upbacterial infections.

Proper restraint should allowthe operation to be done safely andefficiently. Calves less than 36hours of age can often be caughtin the pasture, put on their side,

tied with a short piece of rope andcastrated by one person. Olderbaby calves can often be caught,held and castrated by two people.The castration of older, heaviercalves usually requires a chute.Any time a calf is castratedstanding up, tail restraint isrecommended. Lifting the calf’stail up and pushing it forward overthe back will quiet the calf anddecrease kicking and potentialinjury to the person doing theprocedure (Figure 1).

Fred M. Hopkins, Professor, Department of Large Animal Clinical Sciences, College of Veterinary MedicineClyde D. Lane, Professor, and Warren Gill, Professor, Department of Animal Science

Figure 1. Tail restraint for castratingolder calves standing in a squeeze chute.

Page 4: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

Before beginning castra-tion, one needs to know a littleabout the anatomy of the area.Important structures include thescrotum, testicles and spermaticcord (Figure 2).

The scrotum (sac) is a bag ofnormal skin that holds the tes-ticles. The scrotum is divided intotwo halves by a membrane calledthe scrotal septum.

Each testicle is covered by atough, strong membrane called thevaginal tunic. The vaginal tuniccovering each testicle needs to beremoved during surgical castrationor swelling and infection are morelikely to result.

The spermatic cord attachesto the top of the testicle. Inaddition to carrying sperm fromthe testicle, the spermatic cordcontains all the blood supply tothe testicles.

The testicles produce themale hormone (testosterone)and sperm.

The first step in any castra-tion procedure is to examine thecontents of the scrotum. Twodescended testicles should befound. Removal of these testiclesis the object of castration.Sometimes problems may befound during examination, suchas finding only one testicle. Theother testicle is probably up inthe abdomen and this calf shouldnot be castrated. Contact yourveterinarian for help. About oneout of 200 calves will be affectedby this heritable condition calledCryptorchidism.

The other problem is in-guinal hernia. This problem occurs

rarely, but affected calves have alarger than normal opening intothe abdomen, allowing intestinesto get into the scrotum. One sideof the scrotum is usually affectedand this side will appear unusuallylarge, often near the top. Usuallytwo testicles can be felt. In addi-tion, the enlarged area will feelsoft and mushy (Figure 3). DONOT ATTEMPT TO CAS-TRATE CALVES WITH EI-THER OF THESE CONDI-TIONS. Call your veterinarian foradvice and help.

Surgical castration is pre-ferred. A correctly surgicallycastrated calf will have lessdepression of weight gains and alower incidence of infections thancalves castrated by other methods.Most importantly, a surgicallycastrated calf is almost certainly

Figure 2. Anatomy of reproductive tract of the bull.

Figure 3. Examples of Cryptorchidism(top) and inguinal hernia (bottom).

Page 5: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

Figure 5. Procedure for using theNewberry knife to open a scrotum.

completely castrated. Calvescastrated by other methods areoften incompletely castrated andwill be discounted in the calf’ssale price. These calves will sellfor about $4 per hundredweightless than properly castrated calves.These facts make surgical castra-tion the procedure of choice.

The equipment needed forsurgical castration includes:

• a clean bucket and water• disinfectant such as

chlorhexadine or providol iodine• a Newberry knife, scalpel or

other sharp knife• either emasculators, surgical

clamps or a dull knife.

The first step in surgicalcastration is opening the skin ofthe scrotum. An important point toremember is that a larger openingis always better than a smallerone. Smaller openings do notallow adequate draining and couldresult in a much higher incidenceof infection following castration.Cleanliness is also important.Instruments should be clean andmaintained in a bucket with waterand disinfectant. Hands should bewashed in the disinfectant beforebeginning and between calves.Avoid touching the chute or thecalf’s body. If the scrotum is dirty,it should be washed with disinfec-tant. The water and disinfectantshould be replaced after 15 calvesare castrated because the waterwill become dirty and the disinfec-tant will be ineffective.

A very good method ofopening the scrotum is by use ofthe Newberry knife (Figure 4).

Figure 4. The Newberry knife is anexcellent, safe tool for opening thescrotum.

Before the Newberry knifehas been removed from thedisinfectant, one hand is used topull the scrotum down and back.

The jaws of the Newberryknife are opened and the blade isplaced against the side of thescrotum as high as possible butbelow the testicles to avoid cuttingthem. The blade should always beused at least half way up thelength of the scrotum (remember,

a bigger opening is better than asmaller opening). The jaws of theNewberry knife are closed bysqueezing the handles from side toside. The scrotum is then openedby forcefully pulling the Newberryknife down and back at a 45-degree angle. The result is anincision down both sides of thescrotum (Figure 5).

Another proven method ofopening the scrotum is to removethe bottom one-third to one-half ofthe scrotum, using a sharp knife orscalpel. The bottom of the scrotumis pulled down and back with onehand (using surgical clamps orpliers is safer), while the otherhand cuts off the bottom of thescrotum from side to side (Figure6). Be careful not to cut thetesticles, your other hand or thebig vein inside the calf’s leg.

Next, grasp the tunic-covered testicle and pull it downand back with one hand while theother hand pushes the scrotal skinup (Figure 7).

Keep pulling slowly on thetesticle until you feel the muscle inthe spermatic cord separate.

Figure 6. A clean, sharp knife orscalpel are proven methods for openingthe scrotum.

Page 6: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

Separating the muscle first reducesthe amount of bleeding that occurs.Also, the calf now cannot pull thetesticle back up. Grasp and pull theother testicle (Figure 8).

There are two methods ofremoving the testicles from thecalf. Emasculators are specializedinstruments designed to crush andcut the spermatic cord so thetesticles can be removed. Manytypes of emasculators are availableand all can be made to work well.To use the emasculators, open thejaws and place them straight

across one spermatic cord. Makesure the crushing side of the jaws isdirected up. Also, make sure thatno skin is caught within the jaws.Close the jaws of the emasculatorand squeeze tightly for 15 secondsor more. Remove the testicle anddo the other side (Figure 9).

Another way of separatingthe cord is by using a dull knife.After the testicle has been pulleddown and back, the knife blade isused to scrape the cord in a shavingmotion. Eventually, the cord will besevered. DO NOT CUT THECORD. Cutting the cord will resultin excessive bleeding.

The final step in surgicalcastration is wound treatment.Flies cause annoyance and areassociated with an increase inwound infections. Liberally applyfly spray repellant. Surgicallycastrated animals should bereleased immediately to a clean,dry area. Unweaned calves shouldbe returned to their mothers. A

Figure 7. Removing the testicle.

Figure 8. Slowly pull the testicle untilthe muscle in the spermatic cordseparates.

clean, dry uncrowded area allowsthe calf to calm down and walkaround or lie down as it sees fit. Acrowded, excited calf will bleedmore. If you don’t feel comfort-able castrating a calf, call yourveterinarian. A veterinarian canquickly and safely castrate yourcalves. Other health and manage-ment practices can be done at thesame time.

One of the “bloodless”methods of castration is the use ofthe emasculatome or “clamps.” Thismethod is generally used on older,larger cattle. The emasculatomeis used to “pinch” the cordthrough the skin of the scrotum.Different sizes of emasculatomesare available, as one size can’t beused on all animals. Emasculatomeseventually will wear out and not beeffective. In good working order, anemasculatome closed on an ordinarysheet of paper should crease thepaper but not cut through it.

To use the emasculatome,move one testicle to the bottom ofthe scrotum. Find the spermaticcord above the testicle and moveit to the side of the scrotum. Thejaws of the emasculatome areplaced over the cord and aboutone-third of the way across thewidth of the scrotum. Theemasculatome should be about 2inches above the testicle on thatside. The jaws of the emasculatomeare closed (Figure 10). It should bepossible to feel the cord snapapart after the jaws are closed.After 30 seconds, the instrumentcan be removed. The jaws shouldnever be clamped across themiddle of the scrotum. Someoperators will double clamp each

Figure 9. Using emasculators to crushthe spermatic cord.

Page 7: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

side to ensure successful surgery.Do not store an emasculatome“closed” because this can springthe tool and make it ineffective.While this method is often usedin larger calves, it is slow, diffi-cult and sometimes unreliable.

The least desirable method ofcastration involves the use ofelastrator bands (Figure 11).Elastrator bands are associated witha high incidence of missed testiclesand wound infections, includingtetanus. Growth rates are reduced

for about two weeks after castra-tion. Elastrator bands should not beused in calves older than onemonth of age since the band may

not cut off all of the circulation tothe testicles in older calves.However, this method does notinvolve surgery and the necessaryequipment is inexpensive.

Elastrator bands should bestored in a refrigerator so thatthey maintain their elasticity. Touse an elastrator, first put theband on the elastrator instrumentand press the handles severaltimes to stretch the band. Holdthe handles with the prongspointed up. Close the handles toopen up the elastrator band. Passthe band up and over the scrotum.Pull the scrotum down and makesure both testicles are completelybelow the band. Open thehandles, allowing the band toclose on the neck of the scrotum.Pull the instrument off the band.Always recheck to make sureboth testicles are completelybelow the band. If a mistake hasbeen made, use a sharp knife tocut off the band and repeat theprocedure. After banding, calveswill often show discomfort byrolling on the ground or kickingat their belly for up to 30 min-utes. The calf’s scrotum shoulddry up and fall off in two to fourweeks. Rubber banding methodshave been developed for use inolder, heavier cattle. Thesemethods use surgical rubber tubingand have gained wide acceptancein feedlots. These methods are notdesirable for younger calves, andthe expense of the equipment maylimit the acceptability of thesemethods to the small cow/calfproducer. Castration at older agescan result in stags that are of lessvalue than steers.

Regardless of the methodused to castrate a calf, someswelling is usually noticed by oneday after castration. This swellingis generally gone in a week.

Figure 10. Using emasculatomes or“clamps” to castrate by pinching thespermatic cord.

Figure 11. Using an elastrator toapply bands to castrate young calves.

Producers have been injuredwhile castrating calves. Listedbelow are several tips that shouldhelp do the job more safely• Cg|trate calves as young as

possible. Young calves areeasier to handle and alsoexperience less stress.

• While castrating calves a fewdays old, keep an eye on thecalf’s mother. Some cows maybecome aggressive if youhandle their calves.

• Good handling facilities and anexperienced work crew areprobably the most importantsafety considerations whencastrating older cattle.

• Place a bar behind the calfwhen castrating in a chute toreduce the possibility of beingkicked. Make sure that theperson holding the calf’s tailmaintains firm, steady forwardpressure so the calf will notmove and will kick less.

• Use a Newberry knife to openthe scrotum in surgical castra-tion. You are less likely to cutyourself or the calf.

• If a knife or scalpel is used toremove the bottom of thescrotum, use forceps or pliersto hold the scrotum. Theoperator is much less likely tocut his/her hand.

Castration of the male calf isa simple, money-making practicefor Tennessee feeder cattleproducers. It is a simple proce-dure that is best done early in thecalf’s life. Tennessee feeder cattleshould be marketed only as steersor heifers.

Page 8: PB 1664 - University of Tennesseethe Newberry knife (Figure 4). Figure 4. The Newberry knife is an excellent, safe tool for opening the scrotum. Before the Newberry knife has been

Visit the Agricultural Extension Service Web site at:http://www.utextension.utk.edu/

The Agricultural Extension Service offers its programs to all eligible persons regardless of race,color, national origin, sex, age, disability, religion or veteran status and is an Equal Opportunity Employer.

COOPERATIVE EXTENSION WORK IN AGRICULTURE AND HOME ECONOMICS The University of Tennessee Institute of Agriculture, U.S. Department of Agriculture,

and county governments cooperating in furtherance of Acts of May 8 and June 30, 1914. Agricultural Extension Service

Charles L. Norman, Dean

PB1664-1.5M-1/01 E12-4415-00-005-01