Exam 1

Question 1

There are 6 steps of rumination. What are they, in order?

Answer 1

1. sharp contraction of reticulum
   
   1. forces digesta and fluid to cardia
2. inspiration of air against closed glottis
   
   1. creates vacuum in the thoracic esophagus
   2. bolus of digesta sucked into esophagus
3. regurgitation of bolus + fluid of mouth
4. excess liquids pressed out and swallowed
5. mastication
   
   1. chewing on alternated sides of jaw with each bolus
6. bolus is re-formed and re-swallowed

Question 2

Describe the parotid salivary gland.

Answer 2

• Paired
• at the base of ear to posterior end of mandible
• most important of the salivary glands
  
  • largest (typically >50% of total)
  • highest production of saliva
    
    • 40-50% of total saliva production
  • serous (watery)
  • strongly buffered
  • responds to stimulation from
    
    • Mouth, esophagus
    • reticulorumen

Question 3

What is a ruminant?

Answer 3

4-compartment (compound) stomach

Question 4

Giraffids

Answer 4

• ruminants
• examples
  
  • okapi
  • giraffe

Question 5

What occurs in the first 1/3 of gestation?

Answer 5

• 4 stomach compartments
• esophageal groove
• cell types (Chief, parietal) in abomasum
• distict sacs and pillars within the rumen
• omasal folds (laminae)

Question 6

How does a concentrate selectors eating habits affect their anatomy?

Answer 6

• rapid passage, high fermentation rate
• smaller rumen
  
  • thinner wall, fewer large pillars, evenly papillation
• smaller omasum and abomasum
• larger liver and salivary glands
  
  • rapid rate of VFA processing needed
• shorter intestine (12-15 x body length)
  
  • small intestine 70-73%
  • large intestine 27-30%
  • larger cecum +longer proximal colon

Question 7

List 3 reasons why the feed efficiency (lbs of feed req. per lb of body weight gain) of a cow is inherently lower than that of a pig or chicken

Answer 7

1. adaptations to environment
2. body size
3. feed quality, digestibility

Question 8

How would you explain the process of rumination?

Answer 8

• cyclic, integrated with motility contractions
• stimulated by pressure, destension
  
  • maximal sensitivity in cranial sac, reticulum
    
    • destention receptors
  • course material –> scratch factor
    
    • importance of long forage diets

Question 9

Describe bulk grazers

Answer 9

• most recently evolved
• less selective
  
  • consume “whole plant”
• specialize in digesting cell wall carbohydrates
  
  • larger rumen
  • longer retention times

Question 10

Stratification depends on what?

Answer 10

• forage diets
  
  • types of forage
  • forage maturity
  • processing
  • moisture content
• feed intake
• mat layer dimished on high-conc. diets
• ruminant type

Question 11

What are some human use of ruminants

Answer 11

• edible products
  
  • meat, milk, butter, etc.
• inedible products
  
  • fiber (wool, hair), skin/hide (leather), waste (fertilizer, fuel)
  • inedible fats, tankage, endocrine extracts
• labor, recreation
  
  • traction
  • cultural (rodeo, fighting, hunting, etc.)
• other
  
  • conservation, pest control
  • financial value

Question 12

What is the location and function of the nasolabial glands?

Answer 12

• located in the muzzle
• not true salivary glands
• secretion similar to saliva - keeps muzzle moist
  
  • evaporative cooling (like sweat gland)
• secretes amylase
  
  • animal licks nose, muzzle –> amylase into mouth

Question 13

Answer 13

Question 14

What is crucial in creating a milk replacer in regards to protein?

Answer 14

• trying to recreate casein
• protein quality
  
  • amino acid balance and digestibility
• proteolytic enzyme development
  
  • high pepsin, rennin
  • other enzymes increase with age, exposure
• stimulating properties of casein
  
  • curd formation, regulation of gastric emptying

Question 15

What would a newborn calf’s stomach look like at birth? What would you find?

Answer 15

• rudimentary rumen
  
  • thin walled
  • pale appearance
  • limited pailla development
    
    • sandpaper
• highly developed, fully-functional abomasum
  
  • about 50-70% of combined stomach volume
  • preparation for milk consumption
    
    • enzymes, HCl, volume (storage)

Question 16

Tylopods

Answer 16

• calloused foot/camelids
• pseuruminants
• examples
  
  • camel
  • alpaca
  • llama

Question 17

When and where does microbial innoculation occur?

Answer 17

• typically within the first few hrs of life
• sources of microbes
  
  • environment (manure, soil, etc)
  • feed
  • other animals

Question 18

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types.

NDF, % of intake

Answer 18

Bulk grazers consume more NDF because they are less selective. They eat the whole plant, including the fibrous parts. Increased rumination time allows them to digest higher fiber diets

Question 19

Were herbivorous dinosaurs ruminants?

Answer 19

• extinct prior to appearance of grasses
  
  • ruminants first appeared ~39 million years post dino extinction
• retention time of digesta too long
  
  • VFA broken down before absorption
  • <20% energy capture
• digestive capacity issues
  
  • 50 ton dinosaur
    
    • 3 tons of fresh forage/day –> tons of feces/day
    • no time to ruminate?
• They likely had a simple stomach–> bulk intake, low extraction approach

Question 20

What is crucial in creating a milk replacer in regards to carbohydrates?

Answer 20

• trying to recreate lactose
• consider the enzymes present
  
  • High lactase, low amylase and maltase (NO SUCRASE)
• Glucose, Dextrose ~ Lactose
  
  • pre-digested lactose
  • expensive

Question 21

What can effect saliva output?

Answer 21

• eating and rumination
  
  • nervous stimulation from the gut
• Pavlov’s response
  
  • output can be conditioned into animals
    
    • ex. bottle fed calves
  • association of being fed w/external stimulus
• Physical nature of diet
  
  • processing
  • form and type of feed
  • moisture content of feed
    
    • more plant moisture= less saliva

Question 22

Bovids

Answer 22

• ruminants
• example
  
  • sheep
  • bighorn
  • royal antelope
  • springbok
  • dik dik
  • cattle
  • gemsbok/oryx
  • goat
  • bison

Question 23

Answer 23

A) Dorsal buccal

B) Medial buccal

C, G) Ventral buccal

D, E, F) Sublingual

H) Parotid duct

I) Mandibular

J, K) Parotid

Question 24

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types.

Abomasum weight

Answer 24

Bulk grazers have a higher abomasum weight because they are more efficient at low quality forage utilization

Question 25

How does a bulk grazers eating habits affect its anatomy?

Answer 25

* Slower passage, fermentation (high fiber diet) * larger subdivided rumen * thick muscular pillars --\> motility contractions * uneven papillation --\> ventral = more papilla * larger omasum and abomasum * smaller liver and salivary glands * rapid VFA processing not needed * longer intestine --\> (25-30 x body length) * * small intestine 80-82% * large intestine 18-20%

Question 26

What growth occurs in the last 2/3 of gestation to birth?

Answer 26

* general enlargement of all compartments * initiation of rumen papilla development

Question 27

What are some bulk type grazers?

Answer 27

1. bighorn, dall, and stone sheep 2. sheep 3. cattle 4. mouflon

Question 28

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Cecum weight**

Answer 28

Concentrate selectors have a heavier cecum because their feed passes through the rumen and small intestine rather quickly and further microbe ferementation is needed at the cecum.

Question 29

Pigs and Hippos

Answer 29

* monogastrics * examples * pig * hippo * warthog * peccary/javelina

Question 30

Excessive grain consumption can cause what disorders?

Answer 30

* parakeratosis (hyperkeratosis) * keratinization of papilla * papilla crust over "mushroom" * increased risk of ulceration * bacterial entry into blood stream * ruminal and liver abscesses * similar problem in adult animal if fed high grain diet * associated with lactic acidosis

Question 31

List 3 advantages that grazing/forage-fed ruminant livestock have over use of that fiber for biomass energy or cellulosic ethanol production

Answer 31

1. a cow is a mobing bio-energy plant 2. ruminants are cheaper than 1 plant 3. ruminants waste is more easily disposed

Question 32

Describe the sublingual salivary gland.

Answer 32

* paired * located under the tongue * smaller gland * 10-20% size of parotid * very low saliva production * very high mucous * weakly buffered * responds to stimulation from * mouth, espophagus (moderate) * limited response from reticulorumen

Question 33

Why are ruminants less efficient?

Answer 33

* body size and feed intake * adaptation to environment * ration quality, digestibility * grains push 80% * forages may push 30%

Question 34

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Intestine length, % of small intestine**

Answer 34

Bulk grazers are better at nutrient absorption and must get as much out of their low quality diet as possible. A lot of absorbtion occurs in the small intestine

Question 35

Antilocoaprids

Answer 35

* ruminants * example * pronghorn antelope

Question 36

What are some potential replacement proteins and their downfalls?

Answer 36

* Animal proteins * usually of high quality * BSE concerns limit use * fish protein * generally good balance of amino acids * relatively digestible * prone to lipid oxidation (rancidity) * palatibility concerns * soybean protein (and most legumes protein sources) * Raw soybeans * trypsin inhibitors * inactivation by heat * protein allergens * indigestible carbohydrates * raffinose, stachyose, sucrose * Hydrolyzed soy protein * increased digestibility, but still has above concerns * purified soy protein (isolates, concentrates) * removal of above concerns * coagulation? * limit use older calves

Question 37

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **CP, % of intake**

Answer 37

Concentrate selectors pick out the highest quality parts of the plants (seeds, berries, leaves, etc. )- these habe more protein than the fibrous stems

Question 38

The vagus nerve uses parasympathetic and sympathic control. Give an example of each

Answer 38

* Parasympathetic * gut motility * sympathetic * tension receptors in stomach

Question 39

How many times does an adult bulk grazer chew per day?

Answer 39

30,000-50,000 * This can vary with rumination type * increased selectivity= increased eating time and decreased rumination

Question 40

What are the coordinated steps of motility contractions?

Answer 40

1. initial sharp contraction of reticulum 1. same 1st contraction of rumination 2. 2nd more powerful (biphasic) contraction of reticulum and reticuloruminal fold 1. forces digesta past cardia into rumen 3. sets off wave of contractions which pass over the whole rumen, returning to reticulum 1. subsequent relaxation 2. as digesta passes over ROO, small particles permitted to exit from rumen

Question 41

Describe the mandibular salivary gland.

Answer 41

* Paired * also called submaxillary or submandibular * located along back of jawbone * slightly smaller than parotid * much lower saliva production * high mucous * weakly buffered * responds to stimulation from * mouth, esophagus * NO RESPONSE from reticulorumen

Question 42

How does a concetrate selectors jaw conformation contribute to their eating habits and mastication?

Answer 42

* Smaller, narrow jaw * moderate molar surface area * narrow muzzle * conformation permits selectivity * selects most digestible portion of the plant * seeds, buds, leaves \> stems * slow, deliberate * less efficient chewing, BUT * lower fiber diet decreases need for rumination

Question 43

Explain this diagram and how grasses and ruminants are related

Answer 43

Ruminants evolved as grasses became more available. They likely evolved so they could eat large amounts quickly and avoid predation.

Question 44

Answer 44

A) cardia B) reticuloruminal fold C) caudal pillar D) gas cap E) caudal pillar F) esophageal groove G) reticulo omasal orfice H) reticulum I) Abomasum J) Cranial sac K) ventral sac L) caudal ventral blind sac

Question 45

List 3 non-food contributions that ruminants make to human society

Answer 45

1. recreation 2. fiber 3. leather

Question 46

Study ME!

Question 47

Penssodactyls

Answer 47

* odd-toed ungulates * monogastrics * example * tapir * zebra * horse * rhinoceros

Question 48

If you feed your calf lots of grain, how will that influence his development?

Answer 48

* Fermentation --\> presence of VFA * VFA metabolized by rumen epithelium * BUTYRATE \>\> propionate \> acetate * increased blood flow to papilla * increased nutrient supply = papilla growth * stimulates epithelial \>\> muscular development

Question 49

How do these factors affect saliva output: 1. feed intake 2. palatability 3. type of ruminant

Answer 49

1. Feed intake 1. does have an effect, but more dependent on eating rate 2. Feed palatability 1. increased palatability increases production 3. Type of ruminant 1. Bulk grazer vs. concentrate selector in total intake and forage quality

Question 50

How does isolation effect microbial innoculation?

Answer 50

* develop microflora normally, extcept * will be protozoa-free * transfer of protozoa only by saliva * role of inter-animal contact (licking, saliva, etc)

Question 51

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Parotid Weight**

Answer 51

Concentrate selectors have a higher parotid weight because they eat parts of the plant that need les rumination and need to be broken down before going into the rumen. The saliva provides an essential buffer for high VFA feedstuff.

Question 52

You feed your calf lots of grass hay. How does this influence his development?

Answer 52

* Bulk feed--\> distention of the rumen wall * overall enlaargement of reticulorumen * stimulates musculature \>\> epithelial development * important for contractions of rumen (motility, rumination)

Question 53

Why is the use of starch limited in milk replacers?

Answer 53

* espcially for young calves--\> low amylase, maltase at birth * too much starch causes digestive upset/scours * increased amylase with age and exposure * Can use hydrolyzed starch * limit 40-50% starch in any milk replacer

Question 54

What are some advantages of ruminants over non-ruminant herbivores?

Answer 54

1. predator avoidance 2. enhanced utilization of fiber 3. microbial synthesis of amino acids, vitamins 4. detoxification of plant metabolites

Question 55

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Eating time, min/kg of feed**

Answer 55

Concentrate selectors spend more time per kg of feed because they aren't just tkaing in large amounts at a time like a bulk grazer. Being picky takes time.

Question 56

What is saliva?

Answer 56

secretion from glands lining the oral cavity * contains mostly water * mucous * mineral buffers * aids in mastication and swallowing * moistening, softening of food * lubrication of food bolus for swallowing

Question 57

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Reticulorumen weight**

Answer 57

Bulk grazers have a heavier reticulorumen because their low quality, high NDF diet requires more storage capacity.

Question 58

List 8 intermediate feeders

Answer 58

1. mountain goat 2. pronghorn 3. goat 4. caribou 5. bison 6. elk 7. fallow 8. musk o, 9. red deer 10. chamois 11. ibex 12. winsent

Question 59

The esophageal groove is a reflex contraction spurred by\_\_\_\_\_.

Answer 59

suckling

Question 60

What are 4 arterial branches and where do they supply?

Answer 60

1. Common hepatic artery 1. cranial surface of rumen, plus liver, gall bladder, pancreas 2. Right ruminal artery 1. right side of rumen plus omentum 3. Left ruminal artery 1. left side of rumen, plus reticulum and esophagus 4. Left gastric artery 1. abomasum and omasum

Question 61

Mixing contractions are also cyclic in nature. How long does this cycle take and what is it coordinated with?

Answer 61

* takes up to 50-60 seconds for complete cycle * coordination with rumination * same 1st contraction of reticulum * motility cycle length determines time spent ruminating on given bolus

Question 62

List 4 concentrate selectors

Answer 62

1. white-tailed deer 2. moose 3. mule deer 4. roe deer

Question 63

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Liver weight**

Answer 63

Concentrate selectors have a larger liver weight because their diet is higher in glucose and VFA. So they must be able to process rapid VFA production in liver.

Question 64

Answer 64

1. Milk diet only 2. Milk and grain 3. Milk and hay

Question 65

What will the reticulorumen look like if only fed grain?

Answer 65

* less muscle growth than with forage * VFA (butyrate) stimulates papilla growth * produces smaller, thick-walled rumen with dark appearance due to enhanced blood flow

Question 66

How is blood circulated?

Answer 66

* arterial supply * celiac-cranial mesenteric trunk * celiac artery (abdominal artery * orginated near esophagus * branches into 4 primary arteries

Question 67

What will the reticulorumen look like on an all milk diet?

Answer 67

* similar to that at birth * pale * small papilla * small size

Question 68

How does a bulk grazers jaw conformation contribute to its eating habits and rumination time?

Answer 68

* large jaw * large molar surface area * wider muzzle * rapid ingestion of forage * less selective * lower quality diet * efficient chewing * eating or rumination

Question 69

What does mixing contractions consist of and why are they crucial?

Answer 69

* involvement of wall and pillar contractions * critical function * promotes turnover of indigestible residues * segregates heavier material for rumination * allows finer particles to exit through the reticulo-omasal orfice

Question 70

Why use milk replacer?

Answer 70

* marketing for human consumption * economical alternative * orphaned calf * convience

Question 71

Enzymatic digestion includes what?

Answer 71

* disaccharidases * lactase, maltase, **_but no sucrase_** * **_​_**Rennin (chief cells) * coagulation of milk (formation of curd) * denatures casein * liquid -\> semi-solid curd * cheese-making

Question 72

What are some disadvantages of ruminants over non-ruminant herbivores?

Answer 72

1. large body size (capacity/intake, maintenance) 2. obligate gluconeogenesis 3. reliance upon microbial protein (leveling effect) 4. limited fat intake (essential fatty acid deficiency)

Question 73

The sympathetic nerves have 2 receptors. What are they?

Answer 73

* Tension (distention) receptors * chemical (pH) receptors * below pH 5.4-5.6 or above 8.0 * acidosis, urea toxicity * location * cranial dorsal sac + reticulum * near esophageal groove

Question 74

How can a cow have amylase in her mouth, but not produce salivary amylase?

Answer 74

Confidence booster question ;) Lick their nose/muzzle--\> Nasolabial glands

Question 75

Describe concentrate selectors

Answer 75

* evolved early * highly selective * eat only the most nutritious parts of the plant * seeds, buds, leaves * lower fiber digestion * smaller rumen * poorly developed omasum * larger liver * VFA's

Question 76

What is the role of saliva?

Answer 76

* buffering activity * bicarbonate and phosphate buffers * raises ruminal pH to 5.5-7.5 * majority of buffering activity in rumen * resist drop in pH due to VFA * Taste * Urea recycling * nourishment for microbes (esp. minerals) * anti-frothing properties (role in bloat prevention)

Question 77

What happens to the abomasum if milk intake is too high?

Answer 77

* abomasal bloat * distention on the lower right side * over-coagulation--\> bloat

Question 78

Describe the ruminal pillars

Answer 78

* Cranial and caudal pillars, longitudinal pillars * divide rumen into descrete sacs * cranial sac * dorsal sac * ventral sac * caudoventral blind sac * Muscular contractions * role of movement, mixing of digesta

Question 79

There are three other salivary glands. Name them

Answer 79

1. Labial 2. Pharyngeal 3. Inferior molar

Question 80

Leakage of milk into the rumen increases with solid feed consumption. What is the main cause (anatomical) of this and what does it lead to?

Answer 80

* weakened closure of the esophageal groove * 20-30% milk into rumen * lactose fermentated like starch * increases VFA production * epithelial development! * Bucket feeding vs. bottle feeding. Balanced diet is key!

Question 81

Tragulids

Answer 81

* ruminants * examples * mouse deer * chevrotain "little goat"

Question 82

Describe intermediate feeders

Answer 82

* Characteristics of both bulk grazers and concentrate selecters * seasonally adaptive

Question 83

Answer 83

Question 84

Dicots

Answer 84

* plants with leaves

Question 85

What are the differences in the chewing process between eating and rumination?

Answer 85

* Eating * Rapid ingestion of feed * erratic jaw movements * vertical (chopping, macerating) * 10-15% of particles \<1 mm * Rumination * Slow, deliberate process * lateral (grinding) * consistent duration, force of jaw movements * Bulk of particle size reduction

Question 86

What effect can a low quality forage diet have on development?

Answer 86

hay belly

Question 87

What is McDougall's buffer?

Answer 87

* artificail saliva produced in 1940's * used extensively as a buffer for use in vitro studies in nutrional research * sitmulates more natural environment

Question 88

Answer 88

Question 89

What is crucial in creating a milk replacer in regards to lipids?

Answer 89

* trying to recreate butterfat * fatty acid composition (length and saturation) * lard, tallow, vegetable oils * roughly equivalent nutrient value, digestibility * oxidation (USFA) * physical form is a bigger problem * emulsification of butter fat w/in milk = very small globules * addition of emulsifiers * bile salts, lecithin (soy lecithin, egg yolk)

Question 90

What is the typical saliva output of a adult sheep? Beef cow? Dairy Cow??

Answer 90

* Sheep = 15 L/day * Beef cow = 180 L/day * Dairy cow= 250 L/day

Question 91

Describe neonatal development and factors that affect it.

Answer 91

* (development after birth) * timeline depends on consumption of solid feed * milk-based diet * proportional enlargement with body weight * solid feed * abomasum maintains weight (proportional to bodyweight) * rumen grows at 4-8 times weight at birth

Question 92

What will the reticulorumen look like if only fed a hay diet?

Answer 92

* distention, stretching induced by bulk * increased musclular developmen * slower epithelial development (less VFA, butyrate) * poduces large, muscular rumen * moderate papilla development (low VFA) * somewhat pale (less blood flow)

Question 93

Describe the Reticuloruminal fold.

Answer 93

* separates reticulum and rumen * "sorting device" * reticulum vs. cranial sac * specific gravity * plays role in * rumination * hardware disease * retention of particles for further digestion

Question 94

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Rumination time, min/day**

Answer 94

Bulk grazers spend more time ruminating per day because they only chew their food enough to swallow the first time. They have longer stemmy pieces of forage that need broke down further during rumination --\> lower quality.

Question 95

There are 4 veins for venous drainage. What are they and where do they empty to?

Answer 95

1. Right ruminal vein 2. left ruminal vein 3. reticular vein 4. omasal-abomasal vein All veins empty into the hepatic portal vein * feeds directly to liver * portal-drained viceral * total digestive tract, pancrease, spleen, mesenteric fat * splanchnic bed * PDV +liver

Question 96

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Rumination time, min/kg of NDF**

Answer 96

Bulk grazers are more efficient at particle size breakdown of high NDF feedstuffs due to their jaw conformation.

Question 97

How is chewing behavior important in the eating process?

Answer 97

* Important in fiber utilization * Particle size reduction * Increased surface area for microbes * Increased specific gravity * Lack of upper incisors * Hard upper dental pad * Tearing motion; manipulation of tongue, lips * Upper jaw is wider than lower * Can chew only on one side at a time * Alternate sides (esp during rumination)

Question 98

cervids

Answer 98

* antler bearing ruminants * ruminant * examples * mule deer * whitetail * elk * caribou * moose

Question 99

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Feed Intake**

Answer 99

Bulk grazers are not selective on which part of a plant they eat, so they eat a large amount per bite, increasing their daily feed intake.

Question 100

What happens if there is a lack of rennin in the abomassum?

Answer 100

* lack of coagulation * accelerated abomasal emptying (1-2hrs) * fluctuation in nutrient supply * decreased digestion, hyper/hypoglycemia, other disorders

Question 101

How do ruminants and humans compete for food sources?

Answer 101

* Concentrates * grain ~50% efficient capture of photosynthetic energy * forage up to 90% (whole plant) * land use for crop production * other uses for cellulose * cellulosic ethanol * biomass energy

Question 102

monocots

Answer 102

stemmed plants

Question 103

What is the role of the abomasum?

Answer 103

* regulation of gastric emptying * gradual release of nutrients into the small intestine * 1 meal --\> 12-18 hrs * continuous supply of nutrients

Question 104

What are the five buccal salivary glands?

Answer 104

* Dorsal (single) * also called the palatine gland (in palate) * Ventral and Medial (both paired) * located in the cheek * comparable in size to the sublingual (individually)

Question 105

Discuss how each of these measurments correlates to the type of herbivore (bulk grazer vs. concentrate selector) and why these measurments differ between these herbivore types. ## Footnote **Intestine length, multiple of body length**

Answer 105

Bulk grazers have a longer intestine because they are more efficient at forage utilization. they absorb nutrients broken down by the microbes in the intestine.

Question 106

What is the stratification of digesta within the rumen?

Answer 106

* dorsal sac--\> large coarse particles * gas cap * mat layer or hardpack * medial --\> intermediate particles * migration downward within rumen, fermentation * particles become waterlogged, gas space reduced * ventral --\> small particles, fluid * specific gravity near 1.2 * selective passage through ROO

Question 107

Describe the buccal salivary glands.

Answer 107

* moderate combined output * ventral --\> serous, and mostly mucous * Dorsal, Medial--\> Mucous * Strongly buffered * Responds to stimulation from * mouth, esophagus * moderate response from reticulorumen

Question 108

What factors influence rumination efficiency?

Answer 108

* fiber intake * feed processing * body size * jaw size--\> molar surface area * smaller animal generally less efficient * type of ruminant