Life Sciences Commons^™

Feed Conditioning Effects On Enzymes, Amino Acids, And Subsequent Broiler Performance, Elizabeth Ann Lynch

Graduate Theses, Dissertations, and Problem Reports

There are many things that can be done to improve broiler performance including, but not limited to, pelleting, proper Lys inclusion, and exogenous enzyme supplementation. Pelleting has the ability to improve feed form, reduce wastage, improve bird performance metrics, and decrease pathogens within the feed. Pathogen reduction can be further reduced by hygienic pelleting practices which include an increase in temperature or retention time within a conditioner or hygieniser. However, hygienic pelleting can degrade valuable AA and enzymes (more specifically for the current thesis research Lys and phytase) and make them unavailable to the animal. Supplementing Lys to account for …

Ruminal Protection And Intestinal Availability Of Rumen-Protected Methionine And Lysine In Lactating Dairy Cows, Sara Menchu

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Rumen protected Methionine (MET) and Lysine (LYS) are critical for milk protein synthesis in dairy cows. N-acetyl-L-methionine (NALM) is a MET derivative that consists of L-Met protected with an acetyl group that is attached to the α-amino group.N-acetyl-L-lysine (NALL) is a LYS derivative that is similarly protected. The objectives of these studies were to quantify the gastrointestinal availability of NALM and NALL. Three experiments were run as 3 × 3 Latin square using 3 second lactation Holstein cows that have been fitted with cannulas in the rumen and duodenum. The cows …

Broiler Breeder Amino Acid Levels And Progeny Nutritional Status, Leasea Butler

Graduate Theses and Dissertations

Crude protein needs of chickens have changed due to genetic line differences and selection of those lines for differing broiler traits. Standard commercial broiler strains have been selected to be used to meet multiple processing categories typically at live body weights less than 3.5 kg. In the last two decades high-yielding broiler strains were introduced into the commercial market. These breeds are known as the Cobb 700 and Ross 708. The works included within are focused on the Cobb 700 high-yielding broiler strain, and its response to crude protein, with emphasis on digestible lysine.

Efficiency Of Standardized Ileal Digestible Lysine Utilization For Whole Body Protein Deposition In Pregnant Gilts And Sows During Early, Mid And Late Gestation, Christian Daniel Ramirez-Camba

Electronic Theses and Dissertations

The total daily amino acid (AA) requirements for pregnant sows are based of Lys which is the first-limiting AA in swine diets. The SID Lys requirements are estimated by the NRC (2012) gestating sow model as the sum of those required for maintenance and protein retention divided by the efficiency of SID Lys utilization. The NRC (2012) gestating sow model assumed AA efficiency is constant across stages of gestation and parities; however, this does not reflect the change in metabolic demand of various age sows at different stages of gestation. Therefore, an experiment was conducted to evaluate the efficiency of …

Lysine Bioavailability Of Two Lipid Coated Lysine Products After Exposure To Silages With Different Acidity, Jessica N. Reiners

Electronic Theses and Dissertations

Three experiments were conducted to determine bioavailability of 2 lipid coated Lys products (EB and EC). In an initial experiment, Lys disassociation from 2 lipid coated Lys products was best described by a first-order kinetic model after incubation in alfalfa- or corn-silage at 2 different amounts of acidity. Greater amounts of Lys immediately disassociated from EC (15.7%) than EB (4.9%; P < 0.05). Lysine that initially disassociated in corn silage at low pH (0.5%) was less than corn silage at a more neutral pH (18.7%), whereas Lys that initially disassociated in alfalfa silage was not affected (P = 0.26) by pH. Lysine that slowly disassociated from lipid coated Lys differed by product (P = 0.01), and acidity (P < 0.01) affected amounts of Lys that slowly disassociated differently within alfalfa- or corn-silage (pH × silage = 0.02). Greater amounts of Lys disassociated from acidic corn silage (79%) than neutral corn silage (32%; P = 0.01). However, amounts of Lys that slowly disassociated from alfalfa silage was not impacted by acidity (P = 0.40). Additionally, amounts of Lys that did not disassociate (P < 0.04) within 24 h were greater (P < 0.04) when lipid coated Lys was mixed with neutral silages (44%) compared to acidic silages (21%). However, rate of Lys disassociation from lipid coated Lys products was not affected by acidity or exposure to alfalfa- or corn-silage (P = 0.21). In a second experiment, we measured in vitro ammonia release from EB and EC after mixing with alfalfa- or corn-silage at different amounts of acidity with or without monensin. Ammonia release from Lys increased (Quadratic < 0.01) with greater amounts of time; however, differences between in vitro cultures with added Lys and negative control were not detected until 36 h of incubation. By 36 h, all cultures containing added Lys were greater than the negative control. After 42 h of incubation, ammonia release from Lys was greatest from EC and when lipid and Lys-HCl in amounts identical to EB were provided to cultures; EB, Lys-HCl, and lipid and Lys in amounts identical to EC were intermediate. After 48 h of incubation, ammonia release from Lys in EB was greatest and Lys-HCl was least, but EC and amounts of lipid and Lys-HCl identical to either EB or EC were intermediate. Ammonia release from Lys were less from cultures containing monensin after 48 h of incubation. In experiment 3, 9 white-faced ewes (70.1 ± 5.2 kg BW; 5.3 ± 0.6 yr) were used to measure Lys bioavailability by a slope-ratio analysis from 2 lipid coated Lys products and Lys-HCl after mixing in corn silage. Plasma Lys concentrations increased (Linear < 0.01) in response to abomasal infusion of Lys, and bioavailability of EB, EC, and Lys- HCl were calculated to be 10.74%, 18.82%, and 11.87%, respectively. However, increases in plasma Lys from EB (Linear = 0.41) and Lys-HCl (Linear = 0.36) were not different from plasma Lys supported by diet alone, but the rate of increase in plasma Lys in response to EC tended (Linear = 0.15) to be greater than plasma Lys levels from diet. Evidently, manufacturing method among lipid coated Lys products as well as physical and chemical characteristics of diet can impact availability of Lys from lipid coated Lys products.

The Effect Of Heat Stress And Essential Amino Acids On Production And Metabolism Of Lactating Dairy Cattle, Kimberly Rose Kassube

Masters Theses

Heat stress (HS) causes decreases in production of lactating cattle that is only partially explained by decreases in intake. Evidence suggests that changes in energy and protein metabolism occur to cope with the impact of HS. The objective of this thesis was to determine if the effect of jugular infusion of essential amino acids (AA) ameliorated the negative effects of HS in milk production and metabolism. Twelve multiparous lactating Holstein cows were used in a crossover design to evaluate the effect of thermoneutral (THN) and HS environments along with the absence (CTL) …

Effects Of Dietary Amino Acid Supplementation On Measures Of Whole-Body And Muscle Protein Metabolism In Aged Horses, Christine M. Latham

Theses and Dissertations--Animal and Food Sciences

Sarcopenia is a condition that is most common in aged animals, and is characterized by the loss of skeletal muscle mass and integrity, and can lead to physical disability and poor quality of life. Since skeletal muscle protein synthesis can be limited by the availability of amino acids, supplementation of limiting amino acids to ameliorate the progression of sarcopenia has become a topic of interest in companion animal research. Although there is some data to support the idea that amino acid supplementation improves maintenance of muscle mass in aged horses, the cellular mechanisms behind that improvement have yet to be …

Determination Of Methionine And Lysine Requirements Of Growing Broilers Using The Ideal Protein Concept, Changji Lu

Graduate Theses and Dissertations

Three experiments were conducted to evaluate the responses of broiler performance to Lysine (Lys) and Methionine (Met) during the starter, grower, and finisher feeding phases. All the experimental diets were formulated based on the Ideal Protein Concept.

Experiment 1 evaluated the responses to Lys and Met on live performance of young broiler chickens from 0 to 18 d of age. The mean amino acid ratios to Lys suggested by literature values were used in the formulation based on the Ideal Protein Concept. Six levels of Lys and eight levels of supplemental Met were used in the diets resulting in a …

Optimizing The Feeding Time For Low Crude Protein, Amino Acid-Supplemented Diets For Broilers, Stephen T. Treese

LSU Master's Theses

The objectives of this research were to determine whether delaying the feeding of a diet with reduced crude protein, supplemented with L-Lysine, for several days post-hatching, would result in improved growth performance of broiler chicks and determine an optimal time to feed such a diet to the chick. All experiments were conducted in brooder batteries from 0- to 14- or 18- days (d) post-hatching. Treatments contained a minimum of 6 replicate pens with at least 6 broilers per pen. Two experiments were conducted to determine whether delaying the feeding of a corn-soybean meal (SBM) diet with reduced CP for either …