Increased fearfulness has been associated with adrenocortical activation. Maternal corticosterone (B) treatment increases egg yolk B, and elevated B in ovo enhances chick avoidance of humans. Quail selected for exaggerated (high stress, HS) as opposed to reduced (low stress, LS) plasma B response to stress are more fearful, and more B is found in the egg yolks of HS than LS hens. Therefore, the underlying fearfulness (tonic immobility, TI) and timidity (hole-in-the-wall box, HWB, emergence) responses were assessed in chicks hatched from eggs of LS and HS hens implanted with silastic tubes containing no B (CON) or B (B-IMPLANT) during egg formation. In chicks 14-15 d of age, the number of inductions (INDS) required to attain TI, the latency to first alert head movement (LATHEAD), and duration of TI were determined. In chicks 21-23 d of age, the latency until first vocalization (LATVOC), numbers of vocalizations (VOCS), proportions of chicks vocalizing (PVOCS), and the latencies to head (HE) and full body (FE) emergence from a HWB were determined. LS chicks required a lower number of INDS (P < 0.0005) and less time to achieve LATHEAD (P < 0.02) than did HS ones, although stress line, maternal B-treatment, and their interaction did not affect the duration of TI. During the acclimation period of the HWB tests, more (PVOCS; P < 0.0001) HS chicks vocalized sooner (LATVOC; P < 0.0001) and more often (VOCS; P < 0.0001) than did LS chicks; and, while maternal implant treatment did not affect LATVOC, progeny of B-implanted hens showed a tendency towards less (P < 0.07) VOCS than the CONs. A line*implantation treatment interaction (P < 0.02) was also found for VOCS. Post-hoc analyses of the interactive VOCS means showed that the HS-CON chicks vocalized more (P < 0.01) than the other three similarly less vocal groups. Chicks hatched from eggs of B-IMPLANT mothers also took longer to achieve both HE (P < 0.06) and FE (P < 0.05) from the HWB than did their CON counterparts. Stress line, implantation treatment and their interaction did not alter HE or FE responses. It was concluded that quail stress line genome may be affecting certain fear and alarm responses in chicks via the same or a different mechanism(s) that underlie(s) how maternal B increases in ovo B that in turn alters the fear behavior of progeny.

The purpose of this research was to determine if serum uric acid (SUA) could be used as an indicator of amino acid (AA) utilization in broilers and to determine the Lys requirement of broilers using SUA as a response variable. Treatments were replicated with at least 6 pens with at least 6 broilers per pen. Experiments (Exp.) were conducted from 0- to 14, 17, or 18- d posthatching in brooder batteries. Five experiments were conducted to determine if SUA and uric acid content of the excreta (UAE) could be used to determine AA adequacy of a diet. The results of these experiments indicate that after a 2 h fast, SUA can be used to determine the AA adequacy of a diet as well as UAE. Two experiments were conducted to determine the Lys requirement of female broilers from 0- to 17- d posthatching using growth performance and SUA as response variables. Using daily gain as the response, the Lys requirement of female broilers is 1.27% total Lys for diets formulated with the main source of Lys as SBM. Using gain:feed (GF) as a response variable, estimates of the Lys requirement are 1.30%, 1.42%, and 1.45% total Lys when supplemental Lys is the source of Lys. A final experiment was conducted to determine the effects of supplemental Lys and Met on SUA, serum urea N (SUN), and UAE concentrations. The results of this experiment indicate that supplemental Lys has no effect on SUA or SUN concentrations. The results of this research indicate that SUA concentrations can be used as an indicator of AA utilization in broilers fed AA adequate and deficient diets, but it is not a good response variable to estimate the Lys requirement of broilers.

Unstressed and stressed quail hens selected for exaggerated (HS, high stress) rather than reduced (LS, low stress) plasma corticosterone (B) response to brief restraint deposit more B into their eggs than do their LS hen counterparts. HS hens implanted with B also show reduced egg lay when compared to LS- and HS-control and LS-B-implanted hens. Herein, the effects of stress line on length of egg incubation (LEI) and chick body weight at emergence (BWTE) (Exp. 1) and the interactive influences of line with maternal B-treatment (sub-Q control, CON-, or B-implants) on LEI (Exp. 2) and on egg fertility (FERT), total (TOTHATCH) and fertile (FRTHATCH) egg hatchability, and the percentages of early (ED) and late (LD) dead embryos and pipped (PIP) eggs (Exp. 3) were determined. In Exps. 1 (P < 0.0003) and 2 (P < 0.0001), mean LEI was shorter for eggs laid by HS than LS hens, while chick BWTE was unaffected by line (Exp. 1). In Exp. 2, B-implanted hen eggs also hatched sooner (P < 0.0001) than did CON eggs and line*hen B-implant treatment affected (P < 0.05) the LEI as follows: LS-CON > LS-B > HS-CON > HS-B. In Exp. 3, FERT and TOTHATCH were dramatically reduced (P < 0.0001; both cases) in eggs of HS compared to LS hens and in eggs of B-implant compared to CON hens (P < 0.0001 and P < 0.0002, respectively). Line*implant treatment FERT and TOTHATCH means differed (P < 0.05) as follows: LS-B = LS-CON > HS-CON > HS-B and LS-CON = LS-B = HS-CON > HS-B, respectively. Although FRTHATCH and ED was unaffected by the main treatments, HS-B-implanted hen eggs had more (P < 0.05) EDs. LD embryo and PIP egg percentages were unaffected. The stress line*maternal B findings are important to avian geneticists as they further emphasize the benefits that selection for reduced adrenocortical responsiveness has on hen reproductive performance and they warn poultry producers that stress in the laying barn may abbreviate egg incubation periods and negatively affect egg FERT, TOTHATCH, and ED embryos, particularly in hens genetically predisposed towards high stress responses.

The objectives of this research were: 1) to compare the effect of source and level of inclusion of dried whey permeate (DWP) and a carbohydrate product (CHO) on growth performance of nursery pigs, 2) to evaluate the effect of a fortified nutrient pack (FNP) on growth performance and total tract nutrient digestibility in growing/finishing pigs, and 3) to compare chromic oxide (Cr2O3) and acid insoluble ash (AIA) as digestibility markers for total tract digestibility determination in growing/finishing pigs. Three experiments were conducted to compare the feeding value of DWP (80% lactose) and CHO (40% lactose, 30% sucrose, and 10% glucose) in diets for nursery pigs. Results from these experiments indicate that the inclusion of DWP and CHO improved ADG and ADFI compared with pigs fed a diet without lactose. However, the importance of including a highly digestible carbohydrate source in diets for nursery pigs is more evident as pigs are weaned lighter and younger. Two experiments were conducted to evaluate the effect of FNP (fumaric, malic, citric, phosphoric, and lactic acids, L-carnitine, chromium picolinate, inulin, d-pantothenic acid, and niacin) on growth performance and total tract nutrient digestibility in growing/finishing pigs. Results from these experiments indicate that the addition of 0.25 or 0.50% FNP to the diets did not improve ADG, ADFI, or G/F of growing/finishing pigs. Dry matter, CP, and GE digestibility were not improved (P > 0.1) with the addition of FNP in 50-kg pigs. However, the addition of 0.25% FNP to the diets of 85-kg pigs during the last 14 d of growth, improved CP and GE digestibility. Two experiments were conducted to compare Cr2O3 and AIA as digestibility markers for total tract digestibility determination in growing/finishing pigs fed ad libitum. Results from these experiments indicate that Cr2O3 and AIA offer a rapid and reliable technique for digestibility determination in growing/finishing pigs. However, AIA showed superior characteristics compared with Cr2O3 as its analyzed values are more consistent, produce less environmental impact, and is more cost effective.

The objectives of this study were to provide an overview of fluid milk quality in the U.S., determine if there is a correlation between rapid and traditional tests, determine if results from different analyses correlate with a sensory analysis and to determine any correlation between any of the analyses done in this study. Whole and 2% milks were received from 17 dairy processing plants located in the west, midwest, and southern regions of the U.S in duplicates. Samples were pasteurized at the processing plants by HTST method (161-175oF for 15-25 seconds). For standard plate counts at day 0 no significant differences were found. The mean value was 1.89 log CFU/ml. In day 14, significant differences were found. The mean was 7.58 log CFU/ml. No coliforms were found in any of the samples on either day 0 or day 14. Psychrotrophic counts had no significant differences for the traditional method. 5% of the samples showed psychrotrophic counts. For the rapid method no significant differences were found. The mean value was 0.63 log CFU/ml. 10% of the samples showed psychrotrophic counts. For heat-resistant spore-forming psychrotrophs no significant differences were found. 10% of the samples showed psychrotrophs. For aerobic spores no significant differences were found. The mean value was 1.94 log CFU/ml. HR-1 tests showed no significant differences. The mean was a pink coloration. HR-2 test results did result in significant differences at 48 and 60 hrs, with a mean of a pink color. HR-3 tests showed a mean of pink. Significant differences were found among samples. Fat% results had no significant difference for either milk samples. 2% samples had a mean of 2.08%. Whole milk samples had a mean of 3.43%. Protein content showed no significant differences. The mean was 3.15%. No significant differences were found for somatic cell counts. The mean value was 1.77 log SCC/ml. Regarding sensory evaluation, for day 0 no significant differences were found. The mean score was 7. Day 14 showed significant differences with a mean score of 4.39. Both test methods of psychrotrophic counts shared a high correlation coefficient but a t-test confirmed otherwise. We can conclude that the fluid milk quality in the U.S. needs to be improved.

Plasma leptin concentrations in horses have been shown to vary widely. However, many factors may perturb these measurements. Previous research has documented a link between hyperinsulinemia and hyperleptinemia in horses. This condition has been speculated to be associated with components of equine metabolic syndrome, such as insulin resistance and laminitis. However, many of the methods accepted in diagnosing these metabolic abnormalities are expensive and often difficult to perform. Thus, the objectives of the experiments in this thesis were 1) to determine if it is possible to differentiate hyperleptinemic horses from normal ones by hormone manipulation with dexamethasone, a glucocorticoid analog; 2) to evaluate intravenous injection combinations of insulin and glucose to assess insulin sensitivity; and 3) to assess insulin sensitivity in hyperleptinemic and normal horses using two concentrations of exogenous insulin. In the first experiment, it was determined that a single injection of dexamethasone did not enhance the ability to differentiate between hyperleptinemic and normal horses. In the second experiment, the combined intravenous insulin and glucose tests proved to be very simple and inexpensive. However, repeatability among estimates on the same horses was not strong enough to be conclusive or predictive in assessing insulin sensitivity in horses. In the third experiment, a single injection of exogenous insulin at 0.02 IU/kg of body weight proved to be a consistent and efficacious method of differentiating hyperleptinemic from normal horses. Glucose concentrations in hyperleptinemic horses decreased very little (14%) at this insulin dosage compared to those in normal horses that dropped (P < 0.01) 46% from a pre-injection average of 85 to 46 mg/dL 40 min after injection. It was concluded that a low-level insulin injection coupled with routine plasma leptin estimates constitute a simple method of identifying hyperleptinemic horses.

Transgene expression in stably transgenic organisms is affected by many factors, including the copy number of the transgene in the genome, and by interactions between the transgene and flanking DNA sequences. Transgene copy number has also been shown to effect genetic stability in transgenic plants. Two commonly used methods for transfecting cells are liposome mediated transfection and electroporation. Little is known about the mean transgene copy number or variability of the copy number with these techniques. Quantitative PCR (Q-PCR) has been shown to be an effective method for determining transgene copy number. The objective of this study was to determine transgene copy number after liposome mediated transfection and electroporation. The mean transgene copy number and variability between individual integration events have been determined. Q-PCR conditions were optimized for primer annealing temperature and concentration when amplifying a region of the plasmid hEFGFP used for transfection. The quantitative nature of the Q-PCR reaction was confirmed by amplifying 10-fold dilutions of the plasmid and plotting the threshold cycle (CT) value against the log of the plasmid concentration. A correlation coefficient of 1.00 and a calculated PCR efficiency of 93.3% were obtained from this analysis. Caprine fibroblasts were transfected by electroporation or FuGENE® HD reagent with either a circular or linearized hEFGFP plasmid and plated at low density in medium containing Geneticin®. After 10 days of culture, single cell colonies were isolated and expanded. When cultures reached 1-2 million cells, genomic DNA was isolated. Transgene copy number was determined by amplifying genomic DNA from individual clones representing 1x105 cells with Q-PCR. Transgene copy number was calculated by comparing CT values to a standard curve. The transgene copy number for electroporation circular was 2.7  0.75 (n=32) and 1.3  0.65 (n=19) when using a linear DNA construct. FuGENE® HD using a circular plasmid construct generated a gene copy number of 0.5  0.11 (n=14) and 0.64  0.13 (n=16) for the linear plasmid construct. There were significant differences when comparing electroporation circular to all other treatments, however, there were no differences when comparing electroporation linear, FuGENE® HD circular and FuGENE® HD linear to each other.

Pulsed electric field processing represents a promising non-thermal technology which involves the application of pulses of high voltage (20-80 kV/cm) for less than one second to fluid foods placed between two electrodes. During the application of certain PEF conditions microbial inactivation occurs by causing a pore formation and destruction of the cell membranes. Lactobacillus acidophilus is an important probiotic bacterium used for the production of fermented dairy products. The objective of this study was to study the influence of pulsed electric field (PEF) on the growth characteristics, bile tolerance, acid tolerance, and protease activity of Lactobacillus acidophilus LA-K. Freshly thawed Lactobacillus acidophilus LA-K was suspended in peptone and treated in a pilot plant PEF system (OSU-4M). The treatments were pulse width (3, 6 and 9 µs), pulse period (10,000; 20,000 and 30,000 µs), voltage (5, 15 and 25 kV/cm) and flow rate (10, 60 and 110 mL/min). Control was run through PEF system at 60 mL/min without receiving any pulsed electric field condition. Growth and bile tolerance on control and treatment samples were determined hourly throughout 16 hours of incubation. Acid tolerance was determined at 0, 5, 10 and 15 minutes of incubation. Protease activity was determined at 0, 12 and 24 hours of incubation. The experimental design was a repeated measure design. Data were analyzed using the PROC GLM of the Statistical Analysis Systems (SAS). Differences of least square means were used to determine significant differences at P < 0.05 for main effects (pulse width, pulse period, voltage, flow rate) and interaction effects (pulse width * time, pulse period * time, voltage * time, and flow rate * time). Bipolar pulse width and pulse period significantly lowered acid tolerance and bile tolerance as well as slowed log stage growth of Lactobacillus acidophilus LA-K. Voltage significantly influenced acid tolerance, bile tolerance and growth of Lactobacillus acidophilus LA-K. Bipolar pulse width, pulse period and voltage did not influenced protease activity of Lactobacillus acidophilus LA-K. Flow rate significantly influenced bile tolerance and growth of Lactobacillus acidophilus LA-K. Flow rate did not significantly influenced acid tolerance and protease activity of Lactobacillus acidophilus LA-K.

Considerable research has been conducted comparing the effect of continuous and some form of rotational stocking method on animal and forage performance, but most research utilizes put-and-take stocking rates. The purpose of this research was to determine the effect of 12-paddock rotational stocking method (ROT) or continuous stocking method (CONT) of winter wheat (Triticum aestivum) and annual ryegrass (Lolium multiflorum) pastures on beef heifer and forage performance while maintaining a continuous stocking rate of 3.7 heifers/ha. Two experiments were conducted and analyzed separately due to confounding year and location. Heifer ADG and WG/ha tended to be increased by ROT compared to CONT in Exp 1 (P = 0.10). Differing from Exp 1, heifer ADG and WG/ha was not affected by stocking method in experiment 2 (P = 0.36). Forage mass (Exp 1) was increased by ROT compared to CONT in a time by treatment manner (P < 0.005). Forage mass (Exp 1) was increased by ROT compared to CONT in the final four sampling periods. Forage mass below 500 kg DM/ha in CONT pastures (Exp 1) may have limited heifer DMI in the final two sampling periods. Similar to Exp 1, forage mass (Exp 2) was increased by ROT when compared to CONT in the final two sampling periods (P < 0.05). However, CONT forage mass was not limited in Exp 2. Forage CP (Exp 1) was increased in ROT compared to CONT in a time x treatment manner (P < 0.05). Forage IVTD, NDF, and ADF (Exp 1) were not affected by stocking method, but were influenced by time. Forage nutritive value in Exp 2 was increased by CONT compared to ROT on d 113 in a time x treatment manner (P < 0.05). The results of this research indicate that ROT does increase forage mass on winter wheat and annual ryegrass pastures and may sustain higher stocking rates compared to CONT. However, greater heifer ADG under ROT only occurred when CONT forage mass was limited. The use of ROT compared to CONT under continuous stocking rates of 3.7 heifers/ha does not consistently increase heifer ADG or WG/ha.

Breeding beef heifers to produce calves at 2 years of age could be a profitable management decision. The current practices have proved inefficient, which has justified further research in the area. The objective of this study was to examine the effects of repeated progestogen priming on the attainment of puberty by prepubertal heifers, to evaluate the potential additive effect of progestogen priming plus sodium monensin on the attainment of puberty by prepubertal heifers, to examine subsequent reproductive performance, including the response to synchronization of the estrous cycle, first-service pregnancy rates and overall pregnancy rates and to examine the effects of repeated progestogen priming on follicular dynamics of prepubertal beef heifers. Data were collected and analyzed for birth weight, adjusted weaning weight, postweaning gain/loss in weight and daily gain throughout the experiment. Also the average frame score, average breeding weight, average breeding body condition score, average change in body condition score, average number of animals that showed estrus behavior prior to the breeding season, average number of animals that responded to synchronization, average number of corpora lutea formed during the treatment periods, reproductive tract score at breeding as well as the change in reproductive tract score, follicle populations, change in ovary scores throughout the experiment, pregnancy percentage and the average fetal age at pregnancy determination were evaluated. In this study, treatment groups fed sodium monensin (Rumensin and MGA+Rumensin groups) had significant (P<0.05) advancements in fertility and maturational status when compared with Control animals. The MGA group did excel in follicle development when compared with the Control group, but more heifers became pregnant from artificial insemination combined with natural mating in the Rumensin groups than in the Control group. In conclusion, these experiments provide evidence for the positive effect of sodium monensin on puberty attainment and increased overall pregnancy rates when using artificial insemination in conjunction with natural mating. However, the additive effect of melengestrol acetate, if any, is yet to be defined.