ANSC 318 1st Edition Exam 3 Study Guide Lectures 19 25 Lecture 19 November 11 Where does Texas rank in total feedlot cattle inventory 1st What are the different management options for weaned beef cattle Option 1 weaned calves steers and heifers about 7 8 months old are sent to the feedyard and finished on high grain diets Option 2 calf wintered stockers put into pasture on high roughage diet with limited grain and then finished on high grain in the feedyard Option 3 yearling summer stockers put on pasture with high roughage diet and then finished on high grain in the feedyard Out of the Beef Growing Programs which forage has the poorest quality Stockpiled forages What are the key advantages to feeding a forage based diet first and then a high grain diet Feeding a forage based diet in the earlier stages of life and then switching to a high grain diet will allow faster gain from the grain and compensatory growth leaner muscle less fat meaning the feed gain ratio is lowered and the cattle are more efficient How do you find dairy NE requirements Bos Indicus Dairy 077 BW 75 x 1 2 Bos Indicus 077 BW 75 x 0 9 List 4 factors that effect NEg requirements in beef cattle Gender heifer steers bulls Body weight 800 600 400 Analbolic implants non implanted steers implanted steers Compensatory growth calf feds short yearlings long yearlings Can cattle be implanted more than one time Yes What is the relationship between lean tissue deposition and protein requirements Positive As lean tissue deposition increases protein requirements do as well What is the formula for finding N content of urea Why Urea x 6 25 N Urea is 45 N meaning 1 lb of urea can be converted into 2 81 lb of microbial protein What are the 3 ways to best utilize NPN sources in beef cattle urea is added to high grain diets less effectively used when high roughage diets are fed urea included in diets for short or long yearling cattle compared to diets for calf feds urea included in diets with high concentration of protein feeds high in UIP How do you prevent urea toxicity mix diets well adapt cattle to urea based diets slowly limit urea to 1 3 of total dietary protein Which cattle may require more UIP than others Ex Newly weaned cattle yearling cattle Large frame small frame Revalor implanted nonimplanted What is the proper Ca P ratio What does it prevent 1 5 1 Prevents urinary calculi water belly List the 6 main macrominerals that are important in growing beef diets Calcium phosphorous sulfur magnesium potassium and sodium chloride List the microminerals that are important in growing beef diets Cobalt iron selenium copper manganese and zinc What vitamins need to be supplemented to cattle Vitamin A 2 200 IU kg Vitamin D 275 IU kg if no access to sunlight Vitamin E 60 IU kg What are the goals of a receiving cattle feeding program Restore feed consumption restore rumen function regain body tissue loss from shipping stress and minimize morbidity and mortality rates List the key grain sources fed to cattle in order from most rapidly fermented to least Wheat barley sorghum corn What happens to the speed of digestion as processing of grain increases The rate of digestion increases as well What are the key protein sources for feedlot cattle and their UIP content Soybean meal low UIP cottonseed meal intermediate UIP blood meal high UIP and fish meal high UIP What are the key carbonaceous and proteinaceous silages for feedlot cattle Carbonabeous corn and milo silage grass silage and stover silage Proteinaceous alfalfa silage and clover silage List 3 examples of feed additives and their purposes Monensin ionophore improves feed efficiency Bambermycin improves ADG and feed efficiency Lactobacillus acidophilus probiotic Lecture 20 November 13 What has happened in the dairy cow industry over the past 20 years decreased number of operations same number of cows increase milk production cow and total milk production List the order in which fiber starch and fat effect heat increment Fiber starch fat How do we meet nutrient demands for high producing dairy cows Increase DMI and nutrient density of diet List the stages of lactation their purpose and physiological priorities Early Lactation 0 10 weeks peak milk production occurs within 3 to 6 weeks lactation reproduction growth maintenance Mid Lactation 10 24 weeks milk yield begins to decrease peak DMI occurs within 11 to 13 weeks reproduction lactation growth maintenance Late Lactation 24 weeks milk yield continues to decrease cows regain body tissue reserves reproduction growth maintenance lactation Dry period 5 8 weeks dry period late pregnancy rapid fetal growth Transition period 2 3 weeks dry period late pregnancy prepare for lactation What are milk producers paid for Milk volume milk composition and milk quality What is the impact of diet of VFA production acetate increased with fiber increase fat production in mammary glands precursor to milk production propionate increased with starch in diet How do we maintain adequate fiber levels in lactating dairy cow diets formulate diet to contain a minimum forage concentrate ratio of 40 60 formulate diet to contain minimum of 17 crude fiber or 21 ADF feed minimum 1 to 1 5 of body weight as forage How can we increase digestion time increase particle size increase amount of fiber type of fiber increase lignin What are the short and long term benefits of including adequate levels of effective fiber short term cow will chew more providing more salivary buffers and increasing rumen pH with more favorable environment for fiber loving microbes this will increase acetic acid production a precursor for milk fat synthesis long term help maintain the integrity of the rumen epithelial tissue preventing rumen parakeratosis rumen burnout List 4 additional factors that will effect milk composition type of grain faster rates of rumen starch fermentation may depress milk fat Wheat barley corn sorghum i e corn is safer than wheat because it takes longer Grain processing increased processing increased rate of fermentation Steam flaked cracked dry rolled whole Dietary buffers buffers will increase rumen pH and help minimize milk fat depression dietary fats adding fat may decrease milk protein List 3 situations in which a dietary buffer is beneficial High grain diets heat stress and high corn silage based diets Lecture 21 November 18 What are the benefits of adding fat to the diet Higher energy density of diet while avoiding excess starch or low fiber produce 4 6 lb more