EXAM 3 Flashcards
(44 cards)
What is a least cost ration?
a diet that meets the animal’s needs at the cheapest price
- must consider: cost of feed, transportation costs, processing costs (if processing is performed), and labor involved in feeding the diet to the animal
Why is there no perfect ration?
producers formulate diets for groups of animals (ie. lactating sows) by finding the groups’ average needs
- some animals may have higher or lower nutrient requirements, and eat more or less of the ration, respectively
What is the NRC, and why is it so important?
a. non-profit, non-government organization, puts together a committee of nutritionists who specialize in a particular species
b. National Research Council publishes nutrient requirements and content of feeds every 7 to 10 years (for different breeds, ages, weights, and productions)
What are the 4 different energy units?
- TDN (total digestible energy): - sum of the digestible fiber, protein, lipid, and carb components of a feedstuff/diet (US used to use this unit)
- doesn’t consider diet related energy loss in urine, methane, and heat
- not suitable for ruminants because of microbial fermentation - DE: - amount of energy in the feed- amount of energy lost in the feces
- used for horse diets because they have small dietary energy loss from methane - ME: - used by pigs and poultry because they lose most dietary energy through urine and methane
- NE: - most commonly used for ruminants
- used to measure energy available for both maintenance (NEm) and production (RE) requirements
What are the different protein requirements for ruminants and non-ruminants?
ruminants: - utilize degradable intake protein (DIP), undegradable intake protein (UIP)
- protein requirements met through the protein that reaches the abomasum and SI
- more difficult to formulate ration because hard to predict or directly measure how much protein within a feed will be degraded and how much will bypass microbial fermentation
What is basal metabolism, and what 5 factors influence it?
a. amount of heat produced by the body (the metabolic rate) in a post-absorptive state with minimal physical activity as well as thermal and psychological stress (aka minimum amount of energy required to maintain vital functions in an animal when at rest)
b. 1. body size: larger the animal, the greater its maintenance energy requirement
2. species
3. age: younger the animal, the greater its maintenance energy (on top of growing)
4. previous level of nutrition: animals consistently fed a low energy diet have a reduced maintenance requirement (same applies for animals that are fasted) (body’s protection mechanism)
5. climate: animals in cold climates have an increased basal heat production, and increased basal metabolism (body needs additional heat to maintain internal temp.)
How are muscular work and temperature regulation related to maintenance?
muscular work: - energy expended is directly related to the intensity and duration of the work
- (ex.) heart beating, diaphragm contractions, maintaining muscle tone
temperature regulation: - when temp. drops, body must expend energy to maintain its body temp.
- lower critical temp. depends on level of feed intake, body size, and tissue and coat insulation
Definition of reproduction, indicators of optimal reproduction, and objective of good feeding program.
a. the process by which animals (and plants) give rise to offspring, that consists of a sexual or asexual process and the subsequent growth of the parental gametes and differentiation into a new individual
b. - easy conception
- low rate of fetal and neonatal death
- normal parturition
- maximum litter size
- adequate lactation
- optimal rate of growth of healthy offspring
c. -optimize health and body condition of the dam throughout the various periods
- optimize reproductive performance
- optimize offspring health and development through the weaning period
What’s the average for different animals to reach puberty, and what can affect when it is reached?
a. - cow: 7 to 8 months
- mare: 10 to 12 months
- ewe: 9 months
- sow: 5 to 7 months
- queen: 6 months
- bitch: 6 months
b. body size can affect when puberty hits (well-fed animals grow faster, and reach puberty sooner)
How do you assess an animal for breeding (both younger and mature animals)?
both (young and mature): - in good health and up to date on vaccines
- ideal body weight
mature: - nutrition
What is flushing, and when and how is it used?
a. it’s a technique used on SOME production animals
b. it’s practiced on breeds or industries where litters are more desirable (not cattle or finn sheep/animals that produce litters), like dorset sheep (usually produce singlets)
c. it increases the nutrients arriving to the ovary, which convinces the ovary that the animal is in good nutritional status
- not used on females with good BCS (why)
What the ways to access pregnany?
- abdominal and uterine palpitations
- ultrasound
- radiographs (involves calcification of fetus, and is done after ultrasound)
What are the different gestation lengths of animals?
- cow – 9 months
- sheep (Ewe) and goats (Doe) – 145 to 150 days (5 months)
- pig (Sow) – 3 months, 3 weeks, 3 days!! (114 – 115 days)
- horse (Mare) – 11 months
- cat (Queen) and dog (Bitch) – 63 to 65 days (2 months)
What are the general nutrient requirements during the three trimesters of pregnancy?
1st and 2nd trimesters: pregnant animal is often fed at or slightly above a maintenance diet
3rd trimester: requirements increase rapidly because fetal growth increases rapidly, and mammary gland is growing
What are the differences in maternal and fetal body weight between the species?
guinea pigs: 40% maternal: fetal BW (reason they are so large at birth at can be weaned immediately)
sheep: 13.3% maternal: fetal BW (shorter gestation period than a cow, and generally produce lambs)
cow: 7.5% maternal: fetal BW (typically produces singlet)
sow: 6% maternal: fetal BW (large litter of small piglets that grow rapidly the first few weeks after birth)
humans: 5.8% maternal: fetal BW (very long period of paternal care preparing the baby to function on its own)
higher ratio % means more energy mom is putting into baby
What are the key nutritional factors during pregnancy?
- water
- energy
- protein quantity and quality
- calcium and phosphorous
What are specific nutrient requirements for ruminants and non ruminants?
In well fed ruminants and non ruminants, almost all fetal energy and nitrogen requirements are met by placental transport of glucose and AAs
How does the heat increment (HI) play a role during pregnancy?
- the 3 main sources are: fetal metabolism, uterine and placental metabolism, and non-uterine tissues (liver, GI tract, and kidneys)
- as pregnancy goes on, more energy heat is lost as heat each day
What are the effects of a malnourished animal during pregnancy?
- can negatively impact fetal growth (degree depends on specie, severity and duration of underfeeding, and body condition at the onset of underfeeding)
- has greatest impact on placenta during early pregnancy (why)
if adequate fat reserves, dam will decrease her glucose utilization to spare it for the fetus, and use FAs, and rarely protein, to meet her own energy needs
How are lactose, fat, and protein synthesized?
lactose (glucose-galactose disaccharide): blood glucose enters the milk secretory cell and some of
it is used to synthesize galactose; forms lactose
- milk yield is directly related to the rate of mammary lactose synthesis (lactose is osmotic regulator of milk)
- increase in lactose production = increase in total amount of milk produced
fat: FAs that compose these
triglycerides are either produced from
blood acetate and 3-β-hydroxybutyrate
directly within the milk secretory cell or
enter the mammary secretory cell as
pre-formed long-chain fatty acids from
plasma lipoproteins
- glycerol 3-phosphate required for
fatty acid esterification is synthesized from glucose within the milk secretory cell
protein: albumins and immunoglobulins pass from blood to mammary gland to synthesize whey fraction of protein
- mammary gland takes up AAs, and secrete majority of it into milk
- a lot of transamination occurs in the mammary gland
What are the nutritional requirements during each stage of the cow’s lactation cycle?
early: focus is to meet the cow’s energy needs, while her appetite is declining and energy need is increasing (negative energy balance)
- energy needs are met from body stores (this makes up for the energy consumed in the diet not being enough for milk production, alone)
- increasing grain in the diet reduces gut fill and provides more energy
mid/late: fed a ration that matches her production potential
- cow is pregnant, so high energy need
dry period (3rd trimester): fed high energy diet to prevent mobilization of lipids and support the growth of the fetus
- this period allows mammary glands to rest
- goal is to maintain cow’s BCS from 3.5-4
as cow ages, nutrient requirement increases because she’s gaining weight
What are the feeding guidelines for a calf and heifer?
calf: fed mostly milk until weaned at 5-8 weeks
- functionally a non-ruminant, so easily digestible carbs, lipids, and proteins should be fed
- forage and grain are offered when the calf is a few weeks old (rumen rapidly develops)
amount of forage and grain fed depends on quality and age of calf
heifer: should be fed a diet consisting of forage, additional concentrates, and protein for growth
- at first calving, should be good body size and condition, high feed intake, and delivery of nutrients to mammary glands
What are some metabolic diseases, and what are the type of diets/ways to prevent metabolic diseases?
a. ketosis (decreased blood glucose), milk fever (decreased calcium), and high blood urea nitrogen
b. - provide diet during dry period that is already rationed for early lactation
- diet that contains adequate amounts and lengths of fiber
- early lactation diet with a rumen buffer to maintain proper pH
What condition can occur if blood glucose drops too low?
ketosis:
- ketones can appear in the blood, urine, milk, and breath
- ketone production occurs as the cow tries to mobilize and utilize body fat through the TCA cycle
treatments: infusion of glucose and/or propionate into the blood; avoid BCS over 4.0; formulate ration that maximizes available propionate and carbon entering the TCA cycle
