M3 Flashcards
systematic examination of the eyes and surrounding areas, jaws, mouth and teeth, limb structure, joints, stance, gait
Physical soundness
BBSE four key components
physical soundness
scrotal size
semen assessment
serving ability
inner lining of sheath and is the pink mucosa
prepuce
major factors influencing scrotal size
genotype
age
Liveweight
Nutrition
Timing of nutritional stress
forms the basis of livestock improvement as it allows the transfer of genetic
material from one generation to the next and can greatly influence genetic gain
reproduction
In severe environments where nutrition
is a major stress factor, improvements of 5–10% in weaning rates are possible through?
improving nutrition and management
measures for the bull?
- physical and structural soundness
- scrotal size and sperm production capacity
- semen quality, including morphology
- serving ability/serving capacity.
measures for the cow?
- weight and age at first estrous cycle
- the inter-calving interval
- lactation status at subsequent pregnancy diagnosis.
measures for the herd?
- branding and/or weaning rates
- kilograms of calf weaned per 100 kg of cow mated.
- conception rates determined by pregnancy diagnosis (PD)
this can help to identify areas of loss
calculating a number of reproductive rates
bull costs per calf weaned will depend on?
1.) purchase price
2.) bull salvage value at ultimate sale
3.) number of breeding seasons that involve the bull
4.) whether bulls are checked annually for soundness and fertility.
5.) number of cows per bull
6.) weaning percentage achieved;
7.) bull mortality rates;
common conditions that interfere with fertility
- unequal size of testicles
- hardness of one or both testicles
- thickened scrotal skin.
- softness and flabbiness of testicles and tail of epididymis
often collected as part of a routine BBSE conducted by a veterinarian and examined crush-side under a
microscope to assess factors such as volume, color,
density and motility
semen and spermatozoa
sexual desire of a male to serve a receptive female
libido
it provides an indication of the bull’s ability to serve
serving-capacity test
time when a bull is capable of producing 50 million live sperm per milliliters
puberty
factors influencing when bulls reach puberty
genetic effects and nutritional influences
may be transmitted through sexual intercourse to females, affecting female
fertility, or may indirectly affect male fertility
diseases
can limit the normal testicular function of thermoregulation and result in poorer quality
semen.
nutrition
Such wastage can be due to a large number of factors, including:
- structural defects resulting in lameness and sometimes inability to serve
- degenerative conditions (such as arthritis) limiting serving ability
- age structure in the bull team, with increased proportion of physically unsound older bulls
- reproductive abnormalities, particularly in the testes, penis and prepuce
- infertility due to testicular degeneration, the incidence of which increases with age
- infertility due to disease effects
- traumatic injuries due to fighting.
True or False.
It is not therefore important to keep the age of the bull team as young as possible, not only to gain
benefits from genetically superior sires, but also to ensure the highest level of fertility in the team by
eliminating older and unsound bulls.
False.
A veterinarian should carry out a BBSE to examine bulls for soundness— prior to sale or
purchase, and annually for existing bulls. Such an examination involves:
- checking that the bull’s overall structure including legs, feet and external reproductive organs are
free from defects - assessing the sheath, scrotum and testicles
- measuring and recording scrotal circumference to ensure it is within the acceptable limits
- palpating of the testicles to check for normal tone, size and function.
- collecting a semen sample and a microscopic examination to assess the quality and percentage of
normal sperm
hormonally driven and influenced by genetics, nutrition and management factors
reproduction of female
hormonally driven and influenced by genetics, nutrition and management factors
reproduction of female