Ruminants Anatomy 2 Objectives Reproductive anatomy and Mammary

Ruminants Anatomy - 2

Objectives • Reproductive anatomy and Mammary Physiology – Chapter 3 • GI anatomy – Personal notes

The Importance of Reproduction • Deliver live neonates – Breeding estrous cycle determinations, reproductive exam, AI, embryo transfer, live cover • Genetics, – Gestation – Delivery • Economics

Selection • Estimated progeny differences – Uses: in males – EPD values: birth, growth, maternal, and carcass traits and are reported in the same units of measurement as the trait (normally pounds) – Accuracy: only in same breed. 1 is good and more accurate with more progeny data

Selection • Estimated breeding values – Uses: value of breeding – Differences between EPDs and EBVs • EBV also adds potential for heritability • Pedigrees: more in equine – Breeding systems: inbreeding, linebreeding, crossbreeding (angus+hereford = black brockle face), purebreeding (same breed), outcrossing (different families, same breed) and grading up (grade animal: no documentation of lineage + pure breed) • Conformation: good udder and footing, not cryptochidism

Reproductive Physiology: Table 3 -2

Estrous • Proestrus – Declining progesterone – Gonadotropin releasing hormone (Gn. RH) and follicle-stimulating hormone (FSH) – Increasing estrogen – Follicular growth • Estrus – Peak estrogen – Luteinizing hormone – Ovulation • Metaestrus – Estrogen decreases – Progesterone increases • Diestrus – Progesterone is high – Prostaglandin released if conception does not occur – Destruction of the corpus luteum

Breeding Soundness Examination • Purpose: assess fertility • Examination: before breeding season – Preparation: Safety (chute) – Penis and prepuce • Tranquilize to relax retractor penis muscle – Scrotum and testicles – Measurement of scrotal circumference – Breeding behavior – Semen analysis

Prolonged penile extension: phenothiazine based tranquilizers: e. g. acepromazine, chlorpromazine, and promazine Fibropapilloma: warts NB: permanent damage if out more than 2 hours: penile paralysis, Phimosis (swelling prepuce), paraphimosis (swelling prepuce/penis), Priaphism: blood cannot exit glans penis: swelling penis/penis

Bull Age (months) Size (cm) 12 - 14 30 - 34 15 - 20 31 - 36 21 - 30 32 - 38 > = 31 34 - 39

Semen Collection and Preparation • Collection – Electroejaculation – Artificial vagina – Natural stimulation • Preparation Optimum temp

Semen Analysis • Shake container • Keep warm: 37 C/ 98. 6 F) • Protect from UV light: warm water bath • Use gel free fraction of ejaculate • Extenders: protein, Sugars, antibiotics • cryopreserve Parameter Normal Values Ejaculate volume 5 ml (range 1 -15 ml) Sperm concentration 1200 million/ml (range 3002500 million/ml) Total sperm per ejaculate Typically 4 -5 billion Progressive motility Greater than 30% Morphology Greater than 70% normal Semen samples from a bull (left) and dog (right), showing differences in opacity and concentration

Insemination Timeline

Estrous Cycle Determination • Rectal palpation • Vaginal examinations – Not useful in cattle • Ultrasound via rectum – Better for horses • Observation of standing heat • Vaginal cytology

Ovaries: Rectal palpation Estrus: large soft follicles, relaxed hyperemic cervix

Ka. Mar/ Bovine Beacon

Tail Paint

Tail Paint Other signs: swollen vulva, vaginal discharge, increased vocalization, frequent urination, restlessness

Heat Watch 1. Transmitter with pressure sensitive button on top 3. The receiver accepts the mounting activity signal from the transmitter ge n ra ))) e l i ))) m /2 ))) Receiver ~1 ))))) 2. Mounted onto cow’s rump ) ) using a patch and adhesive )) ) ) ) 4. Information is transferred to computer for processing by Heat. Watch software.

Estrus Synchronization • Ovsynch uses two hormones – PGF 2α and Gn. RH • Ovsynch occurs in three stages – Day 0 - Stage 1: Gn. RH injection to create a new follicle – Day 7 - Stage 2: PGF 2α injection to end the current estrus cycle and regress the corpus luteum – Day 9 – Stage 3: Second Gn. RH injection to cause the new follicle to ovulate and release the egg • All cows will ovulate 24 -32 hours after the second Gn. RH injection – Day 10 – Insemination

Lutalyse • Lutalyse is a veterinary pharmaceutical brand name • Lutalyse is a PGF 2α therapy treatment • If an animal is known to be open (i. e. her ovulated egg was not inseminated), a shot of Lutalyse will end the cycle and start a new one. • Lutalyse/ PGF 2α will cause the death of the corpus luteum, resulting in reduced progesterone production. • Pregnant women SHOULD NOT administer shots of Lutalyse; it can cause their bodies to terminate the pregnancy!

Estrus Synchronization • CIDRs (Controlled Internal Drug Release) – intravaginal progesterone – beef cattle, dairy cattle, goat and sheep industries. – released at a controlled rate – beneficial in large herds

Breeding • Live cover • Prepare perineum/ vulva: cleanse with povidone iodine – Artificial insemination – Embryo transfer: pathogen free embryos AI pipette

Breeding (cont’d)

Breeding (cont’d) • Embryo transfer – Superovulation • Ovulate multiple eggs – Breeding: AI or natural – Embryo recovery • Phosphate buffered saline – Embryo ID – Embryo transfer: recipient

Pregnancy Detection • Failure to return to estrus • Rectal palpation – 25 – 30 days • Ultrasound per rectum – 12 days • Trans abdominal ultrasound – 95% accurate: 60 days • Doppler ultrasound – Week 6 -7 – Fetal heart rate • External palpation – Ballottement – 7 months • Abdominal radiographs: not common • Laboratory tests: estrogen assays: blood, urine, milk

Rectal Pregnancy • Easiest, fastest, cheapest – • • status 25 - 30 days post breeding – US: 12 days (18 days in small ruminants) – Radiograph: 90 days Positive signs of pregnancy – Fetus – cotyledons/caruncles – amniotic vesicle – fetal membrane slip Suggestive signs – Ipsilateral corpus luteum – Ipsilateral middle uterine artery in the broad ligament US: 40 day pregnancy

Fetal Membrane Slip (be gentle, as you can damage a pregnancy by rough palpation) 32 days thread 1 horn 45 small string 1 horn 60 string 2 horns >70 large string

Pregnancy - Cotyledonary • Placentomes – cotyledon/caruncle unit) – You must rule out that you a not palpating an ovary by feeling at least 3. The fetus descends out of reach from 3 -7 months. You can first feel the fetus at 55 -60 days To estimate an aborted fetus they are: 2 months mouse 3 months rat 4 months small cat 5 months large cat 6 months beagle dog 75 days pea size 100 dime 115 nickel 125 quarter 150 half dollar > 150 variable

• • • Gestation: Avg. 283 days 1 – 2 days before parturition: elevated tail head Stage I: Preparatory stage • ~ 6 hours • Inappetance, restlessness, kicking belly Stage II: Delivery • 30 min – 4 hours (Avg. 75 minutes) • Heifers take longer • Head diving posture Stage III • Expel placenta • 4 – 12 hours • PE calf

Dystocia • Fetal or maternal: emergency – Fetal more common • Malformation – “fetal monsters” • Stillbirths • Large fetal size • Fetal malposition – Maternal • Compromised pelvis: fracture/ old injury • Uterine torsion • Rupture of supporting structures

Dystocia • 3 approaches: LUBE!!! – Mutation and traction • Obstetrical chains, calf jacks – Fetotomy: in cattle – C – section • Fetus too large, small pelvis, cervix does not dilate, vaginal prolapse, dead fetus, malformed fetus

Dystocia

Dystocia • C – section – Large fetus – No vaginal manipulations – Failure of cervix to dilate – Vaginal prolapse – Fetal emphysema – Fetal monster

Separate Mammary Glands-Quarters 60% 40% REAR Front quarter is smaller

Fig 29 -3. An illustrated view of the ligaments that permit udder suspension (Courtesy of Iowa State University)

Mammary Gland Structure • Udder: 4 separate glands – A teat hangs from each quarter • sphincter muscle known as streak canal – extra nonfunctional teats • supernumerary teats • Removed in calf

Internal Anatomy • Streak canal – bacteria out • Teat cistern – Duct in teat : 30 -45 milliliters – Separated from streak canal: Furstenberg’s rosettes • Gland cistern – Separated from teat cistern by the cricoid fold – 400 ml of milk • Collecting area for the mammary ducts

Fig 29 -4. A dissected mammary gland showing the gland cistern, teat cistern and streak canal (Courtesy of Mark Kirkpatrick)

1 gallon of milk: 400 gallon of blood • pudic arteries • external pudic veins and subcutaneous abdominal veins Fig 29 -6. Blood flow to and from the mammary gland determines milk producing capability of the cow (Courtesy of Iowa State University)

Digestive System • Cranial fermentors – Forestomach – E. g. cattle, sheep and deer – digest and extract energy from cellulose – utilize the protein from fermentative microbes • Caudal fermentors • • Cecal digestors E. g. horses and rabbits digest and extract energy from cellulose utilize dietary hexose sources directly

Digestive system calf • Esophageal groove – By pass reticulum and rumen and goes directly into abomasum – Grain and forage for rumen development ~ 3 weeks age

Fermentation Ecology • Rumen inoculation – 1 ml of rumen content: ~10 to 50 billion bacteria, 1 million protozoa, variable numbers of yeasts and fungi – Cellulolytic (digest cellulose) – Hemicellulolytic (digest hemicellulose) – Amylolytic (digest starch) – Proteolytic (digest proteins) – Sugar utilizing (utilize monosaccharides and disaccharides) – Acid utilizing (utilize such substrates as lactic, succinic and malic acids) – Ammonia producers – Vitamin synthesizers: vitamin B and K – Methane producers Poor nonprotein nitrogen such as urea to produce VFA, AA, Vit B and K, methane, CO 2

Fermentation Ecology • Rumen p. H between 6 and 7 (6. 2 – 7. 2): Transfaunation • Grain engorgement: p. H <5. 5 – protozoal populations decrease • Products: Sugars -> VFA’s – acetic, propionic and butyric acids

Volatile Fatty Acids • Acetic acid – generate ATP • Proprionic acid – major substrate for gluconeogenesis • Butyric acid, – for energy production.

Ruminant Anatomy • the rumen or paunch • reticulum or "honeycomb, " • the omasum or “book, " • the abomasum or "true stomach. " • Esophagus > rumen reticulum > omasum > abomasum

Reticulum – ‘honeycomb’ • against the diaphragm (2. 5 gal. ) • rumino-reticulum connected by tissue • Heavy objects fall – Hardware disease (traumatic reticuloperitonitis) • No enzyme secretion • Formation of food bolus

Rumen – ‘Paunch’ • largest • sacculated by muscular pillars: dorsal, ventral, caudodorsal and caudoventral sacs • stratified squamous epithelium (Papillae lining) • fermentation vat (2542. 5 gallons, anaerobic bacteria) • Absorbs most VFA • Healthy cows: 1 -2 minutes/contractions

Omasum - book • broad longitudinal folds or leaves • Absorption of water (4 gal. ) • Reduce particle size, ingesta between the leaves will be drier than in other compartments

Abomasum – true stomach – True stomach with a glandular lining (5 gal. ) – HCL and digestive enzymes (proteolytic enzymens: mucin, pepsinogen, renin, lipase), needed for the breakdown of feeds, are secreted into the abomasum – PH decreases from 6 > 2. 5 • Denatures proteins • Kills bacteria and pathogens • Dissolves minerals

H 2 O vital: Drink 10 -14 gal. /dy; Dairy cattle at peak lactation: 45 gal. H 2 O/day (3 -5 gal/ lb milk

Digestive system - Ruminants • The small intestine – measures about 20 times the length of the animal – duodenum, jejunum, and ileum. – Secretions: pancreas and the gallbladder, which aid digestion – Most of the digestive process is completed here • Cecum – SI and LI, where some previously undigested fiber may be broken down – Function of cecum? • Large intestine – last segment of the tract through which undigested feedstuffs pass – absorption of water is the primary – Some bacterial digestion of undigested feed occurs

Function of digestive tract • Eructation (belching) – Large quantities of gas, mostly carbon dioxide and methane, are produced in the rumen • Rumination (4 phases) – 35 to 40 percent of each day ruminating (cud chewing) – During rest periods, feed boluses (cud) are regurgitated for rechewing to reduce particle size and for resalivation. – Feed is more readily digested by rumen microbes as particle size is reduced – Redeglutition: swallowing

Four Steps of Rumination • Regurgitation – Reverse peristalsis carries food to mouth • Remastication – Liquid squeezed from bolus and swallowed – Bolus chewed • Reinsalivation – Adding more saliva • Redeglutition – Swallowing bolus and liquids

Remastication and Redeglutition

Digestive system - Ruminants • Motility of the rumen and reticulum – contractions mix Saliva production – 50 to 80 quarts of saliva – provides liquid for the microbial population, recirculates nitrogen and minerals, and buffers the rumen – buffer for helping to maintain a rumen p. H between 6. 2 and 6. 8 for optimum digestion of forages and feedstuffs • Vomiting – Rare: suspect toxins

References • K Holtgrew-Bohling , Large Animal Clinical Procedures for Veterinary Technicians, 2 nd Edition, Mosby, 2012 • Slides courtesy of Dr. H. D. Tyler, Iowa State University • References: Dr. M. A. Barnes, Virginia Tech and Dairy Cattle Science. 4 th Ed. 2005. • http: //www. vet. kstate. edu/studentorgs/bovine/pdf/Reproductive_ Physiology. pdf • http: //cal. vet. upenn. edu/projects/repropath/FNor mal/ovaries/template. htm

References • Large Animal Clinical Procedures, Elizabeth Hanie. 2006 • http: //www. fsis. usda. gov/ofo/tsc/bse_information. ht m • http: //www. fao. org/docrep/t 0690 e 05. htm • http: //www. infovets. com/books/smrm/C/C 015. htm • http: //www. vivo. colostate. edu/hbooks/pathphys/dige stion/herbivores/index. html • http: //www. extension. umn. edu/distribution/livestocks ystems/components/di 0469 -02. html • faculty. fortlewis. edu/LASHELL_B/Nutr 2 Rumdigestion. pdf • http: //www. das. psu. edu/researchextension/dairy/nutrition/calves/rumen • http: //www. pitt. edu/~super 1/lecture/lec 30761/006. h tm

References • http: //www. vivo. colostate. edu/hbooks/p athphys/reprod/semeneval/collection. ht ml

• Author: Dr. Dipa Brahmbhatt