Lab Final Flashcards
Breeding soundness exam purpose
- is to breed genetically superior, healthy males
- after BSE is complete the male is classified as satisfactory, questionable or unsatisfactory
Primary Follicles
- an oocyte surrounded by a single layer of cuboidal epithelial cells
- will either move forward with folliculogenesis or degenerate
Cattle estrous cycle length
- estrous cycle of a cow or heifer is about 21 days
- the estrus cycle lasts between 6-24 hours
Pars intermedia
- the dividing line between the two tissue types of the posterior and anterior pituitary glands
Vulva
- external portion of the female reproductive tract
- labia major and labia minor (meet to form two commissures, site of union)
- Perineum is located around the external genitalia
- clitoris
Alveoli
- are sack-like structures where milk is synthesized and secreted
- cluster of alveolus
Specificity
- does the assay detect one substance or cross-react and potentially detect others
2 Tissue Layers of the Ovary
- Germinal epithelium
- outer layer of the ovary - Tunica Albuginea
- underneath the germinal epithelium
Mare Estrus behaviors
- urination stance
- urination in the presence of a stallion
- clitoral wink
- immobile stance
- > teaser stallion to elicit response in mare
Ewe estrus behaviors
- nervous/excited behavior
- interest in the ram
- tail wagging
- > presence of a male is necessary to elicit behavior
- > presence of a ram can stimulate non-cycling ewes to ovulate 3-4 days after contact with the ram (RAM EFFECT)
Estrous
- adj. cycle beginning at estrus and ending at estrus
Intralobular Ducts
- drain multiple lobules within a single lobe
Germinal Disc
- the fertilized ova and will develop into the chick
- white spot on the yolk
Disadvantages of Ultrasound
- highly dependent on the skill of the technician to interpret what is being seen
- can lead to negative/false positives
Diffuse Placenta
- horses and pigs
Primordial Follicle in the ovary
- an oocyte surrounded by a single layer of squamous epithelium
- after puberty, the primordial follicles will develop into primary follicles
What is indicative of fertilization occurring
- white membrane forms around the oocyte (fertilization envelope)
- spinning oocyte
Why do we use ultrasound in animal agriculture today?
- to determine if an animal is pregnant
Oviduct/Fallopian Tube
- tubular structure made of 3 sections
1. Infundibulum
2. Ampulla
3. Isthmus
Neurohypophysis
- pars nervosa
- posterior pituitary
B-mode or real time ultrasound
- uses 2D real time imaging
- scanning tissue cross sections at different angles and reconstructing the data into a 3D image
Indirect ELISA
- wells are coated with antigens, a specific type of antibody
- Add the sample and allow antibodies to attach to antigen
- Add a secondary antibody that is tagged with an enzyme is added
- Add substrate to produce the color change
- Color change indicates presence of hormone
Cotyledon
- the fetal side of the placenta
What happens when a cow is milked?
- the sphincter muscles relax allowing the orifice to open
- since the streak canal remains open for an hour or more after milking there is ready access of bacteria to the inside of the gland
- during the dry period the epidermal tissue lining the streak canal forms a keratin plug that effectively seals off the canal
Estrus Behaviors of female
- increased physical activity, such as locomotion, ear flapping and tail wagging
- increased vocalization
- agonist behavior and homosexual behavior towards other females
Ultrasound
- refers to sound waves with a frequency too high for humans to hear
Scrotum
- supports the testes
- responsible for protection and thermoregulation
Estrus in elephants
- detected using a blood draw to track hormones
Ductus Deferens (vas deferens)
- the tube like structure within the spermatic cord
- begins at the tail epididymis
- the epididymis is coiled inside to spermatic cord (convoluted)
- composed of longitudinal and smooth muscle
- has bumps
Three most commonly used methods of semen collection in animal agriculture
- Artificial Vagina (neuroendocrine response)
- Digit Manipulation (neuroendocrine response)
- Electrojaculation (neural response)
Mediastinum
- white-ish colored connective tissue located at the core of the testis that houses/protects the Rete tubules
- white small section in the middle of parenchyma when cut open
Three possible anatomies of the uterine horns
- Duplex
- two cervices
- marsupials and rabbit - Simplex
- no uterine horns
- primate - Bicornuate
- poorly to moderately developed uterine horns
- mare, cow, bitch, queen, sow
Cow or Heifer Estrus behaviors
- nervousness
- mounting other females
- standing to be mounted
- immobile stance
- swollen and red vulva
- chin resting to determine if she will stand to be mounted
Chalaza
- twisted chord that keeps yolk in place
- can also rotate the yolk
Doppler
- used to detect blood flow of arteries and veins in abdomen
Albumen
- serves as protection of the embryo as well as a source of nutrients
4 layers of the Scrotum
- Skin
- outermost layer - Tunica Dartos
- mesh-like smooth muscle located underneath the skin - Scrotal Fascia
- thin tissue located under tunica dartos
- allows testes to move within the skin - Parietal Vaginal Tunic
- the innermost layer of the scrotum
- comes from the peritoneum
- contains blood vessels and veins
Steps from fertilization to embryo development
- Embryology
- the study of the formation and development of the embryo to a fetus - Cleavage Divisions
- blastomeres, morula, blastocyst, trophoblast - Gastrulation
- germ layers (endoderm, mesoderm and ectoderm)
- somitogenesis - Neurulation
- Orangogenesis
- organs produced from diff germ layers - Physical features develop
- can tell what species
Alveolus
- the discrete milk producing unit
- estimated to hold about 1/5 of a drop of milk
Gross Appearance
- color and opaqueness
Air Cell/Sac
- provides the chick with oxygen during later development
Methods of detecting estrus in ewes
- Visually
- females will not mount each other, but you can look for nervous behaviors and tail wagging - Marking Harness
- a harness with a chalk attachment is placed on a ram, when the male mounts the female he will leave chalk to mark her
Sow or Gilt estrus behaviors
- red or swollen vulva
- increased physical activity
- increased vocalization
- mucous discharge from the vulva
- mounting or riding of pen mates
- erect ears
- immobile stance
- > presence of boar is necessary, the more the boar salivates the better
- > use BACK PRESSURE TEST to check for standing reflex
Muscles of the Penis
- Retractor Penis Muscle
- contracts the penis inside the sheath to maintain the sigmoid flexure (normally in S shape) - Corpus Cavernosum
- spongy erectile tissue
- fills with blood to erect the penis - Corpus Spongiosum
- spongy erectile tissue that surrounds the penile urethra
- also fills with blood
- prevent urethra from closing
Myoepithelial cells
- THEY ARE NOT INNERVATED and contract in response to the hormone OXYTOCIN
- results in milk being squeezed out of the alveolar lumen and into the small ducts
Parenchyma
- tan/orange-ish color
- contains seminiferous tubules (site of spermatogenesis), vasculature, lymphatic, nerves, and leydig cells (testosterone)
Sensory nerves are found in the
- teats and skin
- these are critical for initiating the neural pathway of the milk ejection reflex
Preventing polyspermy
- Zona Block
- the zona pellucida hardens
- sperm receptors in the zona pellucida are destroyed - Vitelline Block
- granules reduce the ability of the oocyte plasma membrane to fuse with additional spermatozoa
Three parts of the broad ligament in the female repro tract
- Mesovarium
- supports the ovary - Mesosalpinx
- supports the oviduct - Mesometrium
- supports the uterus and uterine horns
Posterior Vagina
- lined with stratified squamous epithelium
Three parts of a Breeding Soundness Exam
- Physical Exam
- Visual Exam
- Semen Evaluation
Discoid Placenta
- primates and rodents
Concentration
- how many sperm are present per mL of ejaculate
- most common means of determining sperm concentration is to count the sperm under a microscope with a hemocytometer
- hemocytometer is a glass slide onto which a precision grid has been etched
- can also count sperm using a spectrophotometer if a standard curve has previously been determined for similar samples
Vagina
- serves as a copulatory organ, site of urine during micturition and a passive birth canal
Spectral Doppler
- displays blood flow graphically in terms of distance traveled
How to picture a group of alveoli
- as a clump of grapes with the stems acting as the small ducts leading from the alveoli
Ovine Estrous Cycle length
- estrous cycle of the ewe is 17 days
- the estrus cycle is about 24-48 hours
Structures on the ovary following ovulation
- Corpus Hemorrhagicum
- red pimple like structure on the surface of the ovary - Corpus Luteum
- luteal cells that produce progesterone to establish and maintain pregnancy in females
- yellow, large bump - Corpus Albicans
- white scar-like structure, small
Placentome
- refers to both the cotyledon and caruncles
Three ways hormones are detected
- Bioassay
- Radioimmunology Assay (RIA)
- Enzyme-linked Immunosorbent Assay (ELISA)
Sigmoid Flexure
- The s-shaped configuration of the shaft
Cervix
- made up of cartilaginous rings that surround the lumen
- the lumen is lined with columnar epithelium which is responsible for mucus secretion
- chicken neck texture
Posterior Pituitary
- develops from neural tissue, so hormones that are made in the hypothalamus can travel to the posterior pituitary neural connections to be released
How to prevent bacterial infection post milking?
- Post-milking germicidal teat drips minimize the chance of bacteria gaining access to the gland after milking
- Keeping cows standing for a time after milking, such as providing them with access to fresh feed, will also help minimize teat end contamination
The placenta
- provides nutrient and oxygen to the growing fetus
Morphology
- the percentage of sperm with normal shape and size