New technologies for testicular and semen

assessment

György GáborResearch Institute For Animal Breeding and

NutritionHERCEGHALOM, HUNGARY

Introduction

The aim of the examinations is:• to determine if ultrasonic echotexture is associated with

semen production of bulls and boars

• to select those young bulls which are certainly not useful for the AI before the semen examination

• check semen quality by an objective instrument method (dog, bull, boar, ram)

• develop a bull andrological data base

Material and Methods• Examined animals:• H-F AI bulls 6-18 months of age in several examinations between

1998 and 2000• breeding boars (different breeds) 10-60 months of age between

1998-2000• breeding male dogs (different breeds) 14-86 months of age between

1999-2000

• Morphological examinations:• scrotal circumference (SC): Coulter scrotal tape (bulls)

• scrotal form: digital camera (bulls, boars; storing format:

jpg)• testicular consistency (Consitest electronic tonometer; bull,

boar)

Coulter Scrotal Tape

Scrotal forms (bulls)

Scrotal forms (boars)

Examination of the testicular echotexture (bull, boar, dog)

• The ultrasonic examination of the testes was done with a B-mode scanner (Pie Medical, Model 100 LC VET) with an 8 MHz linear-array transducer. Gain was held constant for all examinations.

• The transducer was aligned at the center of each testis and perpendicular to the vertical axis. A custom, electro-mechanical device for holding the probe was used to assure that the same pressure was applied by the probe against tissues upon which liberal amounts of ultrasound coupling gel had been applied (except with dogs).

• At approximately 0.8 kg/cm2 pressure a spring-loaded switch was compressed. At that instance, the ultrasound image was frozen on the scanner and the image was stored.

Examination of the ET by the help of an electronic (auto image freezing

function) transducer’s holder

Consitest electronic tonometer (bull, boar)

• The spring loaded measuring heads use 1500 grams of pressure at all times. Because of the difference in dimension of the two heads (1:3), the penetration to the observed tissue will be different. The transmission changes from a linear movement to a circular movement. A rotating code disk interrupts the infrared light, which counts the impulses for the microprocessor, which then summarizes the results and presents it on the display.

Evaluation of the echotexture (ET) by Scanner 100

• The ultrasonic images of left and right testicles are recorded on disk. The average gray level were characterized on a 256 gray scale: 0 (dark) and 255 (light).

left testis right testis

TesTracto software (developed for the data base) was used for the evaluation of the ultrasonic ET

New New development of the software: distribution evaluation of the gray levels

Ultrasonic examination of the prostate in dogs

Echodenz spot

Echo poor area

Diameter:>5.5 cm

Semen samples and evaluation

• Samples:

• fresh: boar• frozen: bull, dog

• Evaluation:

• the total number of spermatozoa per ejaculate (TNS), the percentage of the live and motile spermatozoa by CASPAR software (Makler chamber was used to keep the 10 m depth)

Using CASPAR for the semen

evaluation

Statistical analysis

• Mean values and Person correlation coefficients

• true positive and negative diagnosis

• false positive and negative diagnosis

• positive prediction value

Results1. Morphological and semen (CASA) data

BULL (n=25) BOAR (n=14)Age (mo) 14.0 ± 2.7 12.3 ± 4.7

SC (cm) 32.9 ± 4.1 -

TM (mm) 4.9 ± 1.2 7.2 ± 1.4

ET (0-255) 44.7 ± 18.0 56.3 ± 6.0

Live % 71.0 ± 10.8 79.0 ± 10.2

Linear % 68.0 ± 8.6 47.3 ± 11.6

Speed (m/s) 96.9 ± 10.9 50.7 ± 7.8

Scrotal skin(mm)

- 6.1 ± 1.0

2. Correlation coefficients and probabilities

BULL BOAR

Age vs. ET -0.12 (NS)* -0.81 (P<0.001)

Age vs. SC 0.87 (P<0.001) -

Age vs. Live % 0.45 (P=0.02) 0.30 (NS)

SC vs. Live % 0.49 (P=0.01) -

ET vs. Live % -0.46 (P=0.02) -0.37 (NS)

ET vs. Scrotal skin - -0.81 (P<0.001)

TM vs. Scrotal skin - 0.37 (NS)

TM vs. Live % -0.23**(NS) 0.40 (NS)

* Usually around -0.50, significant** Usually it’s a positive, significant correlation

3. Correlation coefficients and probabilities for H-F bulls with visually examined semen data (n=88)

SC ET TM SV SD TSN LIVEAGE 0.6453 -0.3921 0.3558 0.5574 -0.1767 0.3887 0.3557

0.0000 0.0003 0.0007 0.0000 0.1016 0.0002 0.0007SC 1.0000 0.2772 0.5287 0.3719 0.0519 0.3390 0.4051

0.0000 0.0093 0.0000 0.0004 0.6333 0.0013 0.0001ET 0.2772 1.0000 0.7014 -0.0895 -0.0407 -0.0865 -0.0666

0.0093 0.0000 0.0000 0.4098 0.7084 0.4259 0.5398TM 0.5287 0.7014 1.0000 0.1312 -0.1184 0.0450 0.0485

0.0000 0.0000 0.0000 0.2257 0.2748 0.6787 0.6555SV 0.3719 -0.0895 0.1312 1.0000 0.2466 0.8822 0.5059

0.0004 0.4098 0.2257 0.0000 0.0213 0.0000 0.0000SD 0.0519 -0.0407 -0.1184 0.2466 1.0000 0.5136 0.1965

0.6333 0.7084 0.2748 0.0213 0.0000 0.0000 0.0681TSN 0.3390 -0.0865 0.0450 0.8822 0.5136 1.0000 0.5325

0.0013 0.4259 0.6787 0.0000 0.0000 0.0000 0.0000LIVE 0.4051 -0.0666 0.0485 0.5059 0.1965 0.5325 1.0000

0.0001 0.5398 0.6555 0.0000 0.0681 0.0000 0.0000

4. Categories of diagnosis (just for bulls)

* Based on SC, ET and TM. Examination of the bulls was performed at least 2 months prior to the semen production.

* Semen was measured for at least 2 months after the beginning of the semen production: SV, SD, TSN

• NP - No predicted semen production problem• PP - Possible predicted semen production problem• NUAI - Prediction: not useful as a breeding bull

5. Prediction results in 1998

NP PP UAINumber of DG 49 41 4

Correct DG 47 22 4

Incorrect DG 2 19 0

Sensitivity 0.71

Specificity 0.94

Positive predictionvalue

0.61

Negativeprediction value

0.96

6. Prediction results in 1999NP PP UAI

Number of DG 42 52 3

Correct DG 39 35 3

Incorrect DG 3 17 0

Sensitivity 0.69

Specificity 0.93

Positive predictionvalue

0.69

Negativeprediction value

0.93

Possible reasons of the incorrect predictions

Calcification. Dg.: PP

normal semen production 6 months later

Small SC (20 cm at 8 months of age

normal SC size (32 cm) and semen

production4 months later

Possible reasons of the rejection

Cryptorchidism

Left testis: orchitis

right testis: fibrosis

Results of the dog semen freezing

Examined dog 17Semen collection 14Oligospermia 3Aspermia 2Freezing 11Good quality of thawed semen 8

Conclusions

• The morphological parameters (SC and ET, possibly TM) of testis and scrotum reflect semen measurement.

• Andrological data bases for males help define the “gold standards” of these markers at different age levels prior to semen production and assist in identifying young bulls which are not useful to the AI industry.