The 17th Annual
NC State
University
Undergraduate Research Symposium
Biological
Sciences:
Applied
Sciences (Crop, Poultry, Animal,
and Horticultural
Sciences)
Abstracts
Abstracts are listed in alphabetical order by the last name of the
corresponding author.
- Biological Sciences abstracts
Applied Sciences (Crop, Poultry,
Animal, and Horticultural Sciences)
Ecology, Environmental, Conservation,
Botanical
Molecular, Biochemical, Genetics, Cell
Biology
Zoology, Physiology, Behavior,
Neurobiology
- Engineering & Technology abstracts
- Humanities, Social Sciences, Psychology abstracts
- Physical and Mathematical Sciences
abstracts
|
Baker, Crystal L. |
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Department(s): |
Animal Science |
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Research |
Kimberly Ange-vanHeugten/Animal
Science R. Douglas Cope, DVM, Denton Animal
Hospital |
|
Title of Presentation: |
Obesity in Canis Familaris |
Obesity is recognized as a human
disease; however, it also affects canines (canis familaris). Obesity is defined
as a pet being overweight by 20-25%1.
It is estimated that 24 to 44% of the canine population in the USA are obese2. As the human incidence of obesity
continue to escalate so does the frequency of this condition in canines3. Obesity in canines has been linked
to numerous health problems such as heart disease, hyperthyroidism, and
arthritis. The scientific approach taken by a veterinarian is often more
critical of a pet’s weight than the owners 4.
Thus, many owners simply do not understand the need to regulate their pet’s
weight. Most veterinarians use a scientific standard to determine how a pet’s
weight compares via Purina Mills Inc.’s (PMI) Body Condition Scoring
(BCS)System. This system characterizes canines from 1 to 9 with 1 being
emaciated and 9 being obese. Ideal BCS is between 4 to 5. A study was completed
to determine if adequate exercise and dietary changes could reduce a dog’s
weight. Ten clinically obese dogs with BCS ranging from 8 to 9 were selected to
participate in this study. This study, conducted at Denton Animal Hospital with
funding via PMI, entailed taking blood samples from the canines and changing
their diet to a recommended amount of Purina OM (overweight management) for ten
weeks. The diet was reevaluated weekly and changes were made to ensure the
optimum weight loss of 2 to 3%. At the end of this study blood samples were
collected again for comparison. The study participants ranged in starting
weight from 126.7 to 16.6 lbs. Therefore, all weight loss and subsequent diet
changes were calculated on a percentage of the pet’s total body weight. This
enables comparisons to be conducted among the various dog breeds. The weight
loss varied from a gain of 3.4% to a loss of 15.0% with an average total weight
loss of 6.8%. The average weight loss rose to 7.9% when the one outlier that gained
weight was removed. Blood parameters documenting potential health benefits
within this study are forthcoming. However, it appears that proper weight loss
for obese canines is possible with veterinary assistance.
|
Beard, Adam W. |
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Department(s): |
Animal Science |
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Research |
H. C. Liu/Animal Science |
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Title of Presentation: |
Yeast Two-Hybrid Screen for Novel
Host Interacting Partners with the Marek’s Disease Virus Protein UL49 |
Marek’s Disease (MD) is a very
detrimental disease that greatly impacts the poultry industry. Marek’s Disease Virus (MDV), causes this
contagious neoplastic disease in chickens and has a worldwide distribution. To
further elucidate MDV pathogenesis, a cDNA library from chicken splenic cells
was constructed and used in a yeast 2-hybrid screen of the MDV protein
UL49. The UL49 protein, localizes
efficiently and rapidly into nuclei, and has been shown to bind DNA. The UL49 protein-encoding gene was cloned into
a bait vector and transformed into the bait yeast strain AH109, which was then
mated the prey yeast strain Y187 containing the cDNA library. The yeast was plated onto selection agar,
lacking the amino acids histidine, tryptophan, and leucine. Colonies were screened multiple times to
eliminate false positives. Prey plasmids
were isolated from colonies determined to contain a positive protein-protein
interaction, via a β-galactosidase assay and sequenced. Sequences were analyzed using the NCBI BLAST
program, and determined to be Gallus
gallus ubiquitin-conjugating enzyme (UBC9).
This protein is used in cell nuclear architecture, chromosome
segregation, and is essential for cell cycle progression. UL49 is a tegument protein known to localize
to the nucleus. Therefore one
possibility for this interaction could be that UBC9 transports UL49 to the
nucleus.
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Bryant, Milton R. |
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Department(s): |
College of Natural Resources |
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Research |
Glenn P. Catts/College of Natural
Resources |
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Title of Presentation: |
Adding Value to Biomass Harvesting
Beyond Wildfire Risk Reduction |
Increasing population growth results
in increased energy needs and more wildland urban interface. The use of a
biomass harvesting system has the potential to provide useful products, including
energy, and reduced wildfire risk. A viable biomass harvesting system must be
economically feasible. Energy prices for biomass, although increasing, are
currently too low to support a biomass harvesting system dependent on energy
harvests alone. Existing wood product markets currently exist for tree biomass
in the form of sawtimber and pulp, but no specific markets exists for shrub
derived biomass (i.e. small diameter, woody biomass). In pocosins, this type of
shrubby biomass constitutes the greatest source of wildfire fuel and hence the
greatest source of wildfire risk. To make harvesting pocosin biomass
economically feasible, the potential for additional 'value-added' markets needs
to be explored. In this project we examine the potential for extracting
'value-added' products from small diameter, woody pocosin biomass. The products
examined were sugars useful in the fermentation of ligno-cellulosic biomass
into ethanol and the anti-microbial efficacy of essential oils.
|
Chandramouleeswaran, Sindhu P. |
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Department(s): |
Biomedical Engineering Microbiology |
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Research |
Leon Boyd/Food Science |
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Title of Presentation: |
Effects of Pectic Enzyme on
Blueberry Textural Attributes |
Blueberries are often called
"super fruits" due to their nutrient richness, high antioxidant
content, and versatility for incorporation into popular consumer food products.
The use of blueberries by food processors and consumers is highly dependent on
not only their nutritional value, but also their textural and sensory
attributes. The main goals of this project were to optimize the application a
commercial pectic enzyme (Rapidase™) to improve textural qualities of
individual quick frozen (IQF) blueberries while sustaining antioxidant levels. Vaccinium ashei (rabbiteye variety,
Tifblue cultivar) blueberries were infused with commercial pectic enzyme at 1%,
2%, 5%, and 10% aqueous solution of Rapidase™ by two techniques: soaking and
vacuum infusion. Blueberries were incubated for a period of 4 months at -20°C,
after which puncture tests were conducted using a TA.XT Plus texture analyzer
(Texture Technologies Corp.). Results showed that soaking for 3 minutes is more
effective at reducing the force required to puncture the skin of blueberries in
comparison to vacuum infusion at concentrations of 2%, 5%, and 10%. Vacuum
infusion for 1 minute was found to be more effective at reducing puncture force
than 3 minutes of vacuum infusion at similar concentrations. Comparison of
controls samples not submitted to Rapidase™) treatments showed that, with the
exception of 1% vacuum infusion for 3 min, all treatments were effective in
reducing puncture force. Comparisons of the effect of Rapidase™ on antioxidant
retention were conducted using the oxygen radical absorbance capacity (ORAC)
assay and total phenol content. Results indicated that all enzyme treatment
concentrations were more effective than the control in inducing an increase in
the antioxidant content following incubation with Rapidase™. Results of this
study showed that the application of a pectic enzyme holds the potential to
reduce the toughness of selected cultivars of rabbiteye during frozen storage.
|
Davis, Kristen R. |
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Department(s): |
Animal Science |
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Research |
Steven P. Washburn/Animal Science |
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Title of Presentation: |
Effects of Cross Fostering on
Measures of Dominance, Pre-Weaning Growth, and Survival of
Pigs Reared in a Deep-Bedded Production System |
Cross fostering lessens the metabolic
demands on sows during lactation by standardizing litter sizes. The efficiency of cross fostering has not
been studied in systems such as the deep-bedded hoop house swine production
system at the Center for Environmental Farming Systems. The objectives of this
project were to examine whether fostered pigs differed from native pigs in
survival and in dominance as measured by teat suckling location. Anterior teats
on a sow produce more milk and piglets suckling on the anterior teats are
usually more dominant. Pigs of uniform
size were cross fostered within 24 hours of birth. The study had 8 intact litters
(56 native pigs) and 17 fostered litters (111 native plus 39 fostered
pigs). At 7 and 10 days, each pig was
observed nursing and data recorded included sow and location of teat
suckled. Teat suckling positions were
not statistically different for fostered versus native pigs in fostered litters
with 50% of the fostered pigs vs. 36% of native pigs nursing the first 2 sets
of anterior teats. Weight gains did not differ significantly between fostered
and native pigs. Mortality rates of
native pigs in intact litters (25%) vs. native pigs in fostered litters (18%)
were not statistically different. In
contrast, mortality of fostered pigs was significantly greater than the
mortality among all native pigs (33% vs. 20%, P<0.01). If pigs were older than 24 hours at
fostering, sows showed greater levels of aggression towards those fostered
pigs. In some cases, pigs fostered after 24 hours were unsuccessfully fostered
and were reclaimed by the original sow. Overall, mortality rate of pigs was
higher than desirable and mortality rate was greatest among fostered pigs. Although weight gains among surviving pigs
were similar, higher mortality of fostered pigs limits application of cross
fostering in a deep-bedded production system.
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Fuller, George T. Campbell, Rachel Fuller, Thomas Oh, Lydia Weiner, Zachary |
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Department(s): |
Food, Bioprocessing and Nutrition
Sciences |
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Research |
Brian E. Farkas/Food, Bioprocessing
and Nutrition Sciences Lynn Turner/Food, Bioprocessing and
Nutrition Sciences |
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Title of Presentation: |
Development and Shelf-Life Study of
a Novel Whey Protein Beverage |
Whey protein beverages have been consumed
for many years by athletes seeking a concentrated and highly absorbable protein
source. The majority of whey protein
beverages in the marketplace are shelf-stable, aseptically processed and thus
expensive to manufacture. In addition,
the thermal treatment used in aseptic processing can result in protein
aggregation and a turbid product. The
functional properties of alpha-lactalbumin are unique compared to other whey
proteins. Alpha-lactalbumin, containing
4.8 g/100 g of tryptophan, increases the body’s production of serotonin. Research has indicated that consumption of
alpha-lactalbumin results in enhanced sleep, improved mood in stress vulnerable
subjects and reduced cortisol concentrations in the blood without causing
drowsiness. This research project sought
to produce a clear, alpha-lactalbumin based whey protein isolate beverage using
conventional high temperature, short time (HTST) pasteurization. The health benefits of the beverage were
enhanced with the addition of vitamins C and E as antioxidants and thiamin (B1)
to assist in reduction of fatigue after strenuous exercise. Shelf stability of the HTST beverage was
monitored every two days for a 21 day target shelf-life, at 4°C. Analyses included aerobic plate count,
turbidity, viscosity, and assays for nutrient concentrations. The HACH 2100AN was used to determine
turbidity, the Bohlin VOR rheometer was used for viscosity measurement, aerobic
plate counts were performed using 3M Petrifilm and vitamins C, E and B1 were
assayed using standard AOAC methods. A
uniquely functional, clear whey protein beverage was produced using
alpha-lactalbumin whey protein isolate.
|
Gudaitis, Tonya L. Bowles, Kristina D. |
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Department(s): |
Animal Science |
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Research |
Vivek Fellner/Animal Science |
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Title of Presentation: |
Alternative Silage Diets and Their
Effect on Milk Production by Holstein Cows |
The objective of this experiment was
to determine the performance of lactating cows fed small grain silages in
comparison to those fed corn silage.
Prior to the beginning of the experiment 23 Holstein cows were weighed
and grouped by days in milk, production, and parity. Each was randomly assigned to one of four
experimental diets as follows: 1) Corn Silage (CS), 2) Hulless Oat Silage (HO),
3) Normal Oat Silage (NO) and 4) Wheat Silage (WS). The CS diet consisted of
36.8 % corn silage, 9.5% alfalfa hay, concentrate mix, and vitamin mineral premix.
Small grain silages were included at 23 % of the DM replacing CS. The
experiment was conducted for 60 days. Animals were housed in free stalls
equipped with Calan gates allowing for individual intake measurements. Feed intake as well as milk weights were
recorded daily. Body weights were obtained prior to and at the end of the
trial. Milk samples were taken once each month at a.m. and p.m. milkings. Data were analyzed as a randomized complete
block design using the Proc Mixed procedure of SAS. Results showed dry matter
intakes higher (p < 0.01) for NO (24.3 kg) and WS (23.6 kg) in comparison to
CS (22.5 kg) and HO (22.2 kg). Milk
production was highest (p< 0.01) for CS (34.4 kg), intermediate and not
different for HO and WS (32.2 and 32.7 kg, respectively) and least (29.9 kg)
for NO. Milk fat and milk protein were
not affected by treatment (p > 0.05).
Milk lactose percent was reduced (p < 0.05) with HO compared with the
other 3 treatments. Milk urea nitrogen
was also reduced with the NO compared to the other 3 treatments. While cows fed NO and WS had greater intakes,
they produced less milk when compared to CS.
|
Graham, Whitney K. |
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Department(s): |
Animal Science |
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Research |
Eric van Heugten/Animal Science |
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Title of Presentation: |
Effect of Stabilized Rice Bran on
the Development of Antibiotic Resistant Bacteria in Weanling Pigs |
Three-week old piglets (n = 60) housed
in 20 pens were assigned to one of four dietary treatments for a four week
feeding trial. Dietary treatments
consisted of: 1) control diet without antimicrobials (ANT); 2) control diets
with 10% stabilized rice bran (SRB); 3) diet with ANT without SRB; 4) diet with
ANT and SRB. The antibiotics fed were chlortetracycline (CTC), sulfamethazine
(SUL), and penicillin (PEN) at 110, 110, and 55 mg/kg diet, respectively. Fecal
samples were collected on d 14 and 28 for isolation of coliforms and Enterococcus (ENT). Resistance to CTC and PEN at 60, 80, and 100
µg/mL and SUL at 100, 150, and 200 µg/mL were tested. Pigs fed the control diet with SRB had an
increased percentage of CTC resistant coliforms compared to pigs fed the other
diets. Coliform resistance to all
antibiotics tested decreased from week 2 to week 4 (time effect, P < 0.001).
As level of antibiotic in the culture medium increased resistant coliforms
decreased. At week 4, ENT resistant to
PEN was lower for pigs fed ANT with SRB compared to pigs fed the other diets
(diet x time effect, P < 0.05). Also at week 4, percentage of PEN resistant
ENT was lower for pigs fed control with SRB compared to pigs fed control (diet
x time effect, P < 0.05). Resistance of ENT to CTC and SUL decreased from
week 2 to week 4, but resistance to PEN increased (time effect, P < 0.001).
As level of antibiotic added to the culture medium increased ENT resistance to
CTC and SUL decreased (P < 0.001).
Resistant bacteria were present regardless of use of antimicrobials.
Feeding pigs SRB had no effect on PEN resistant coliforms. However, SRB lowered
the occurrence of PEN resistant ENT.
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Jackson, Katherine A. |
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Department(s): |
Animal Science |
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Research |
Steve P. Washburn/Animal Science |
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Title of Presentation: |
The Effect of Milk Feeding Method on
Cross-sucking Behavior in Pasture-based Dairy Calves Fed Once Daily |
Cross sucking among group-managed
dairy calves increases concerns of udder malformation and mastitis due to
irritation of the sucked area. We investigated whether pasture-raised dairy
calves differed in cross-sucking activity when fed milk once daily in an open
trough (Group 1, n = 8) compared to those allowed to suck from a barrel teat
feeder (Group 2, n = 8). Calves of both
genders were used and balanced across groups among Holsteins, Jerseys, and
crossbreeds. Each group received one 30.5 L milk meal a day and had free-choice
access to a calf starter and water on adjacent pasture paddocks. The hypothesis was that lack of sucking
during eating might lead trough-fed calves to increased cross-sucking behavior.
Calves were observed during 13 periods over 8 wk from the time they reached
pasture until after weaning. Scan sampling using direct observation began upon
delivery of milk and continued at 5-min intervals until 60 min after milk was
fed. Additional observations were made during the same time post weaning. Data
recorded by visual observation included general postures of calves (standing,
lying head up, or lying head down) as well as specific activities such as,
drinking or sucking milk, self-grooming, licking another calf, licking or
nibbling on object, cross sucking,eating, or inactivity. The average number of
observations per calf was 12.3 ±0.02 per period. Incidence of cross sucking at
and just after feeding time within the trough-fed group averaged 2.2 ±0.4,
whereas the teat-fed group averaged only 0.15 ±0.05 incidences of cross
sucking. This behavior accounted for 18% of total activity for trough-fed
calves and 1% of activity for teat-fed calves. In contrast, during post weaning
the trough-fed group reduced cross-sucking behavior to 0.8 ±0.3 incidences but
teat-fed average increased to 0.6±0.3 incidences. Although trough-fed calves
had higher cross-sucking behavior before weaning, occurrences of cross sucking
were similar for both trough-fed and teat-fed groups post weaning so long-term
effects may be minimal.
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Korby, Ambre C. Marshall, Stephanie M. Lee, Jae J. |
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Department(s): |
Food, Bioprocessing, and Nutrition
Sciences |
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Research |
Brian E. Farkas/Food, Bioprocessing,
and Nutrition Sciences Lynn G. Turner/ Food, Bioprocessing,
and Nutrition Sciences |
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Title of Presentation: |
Extraction and Supplementation of
Human Milk Proteins for Improving Preterm Infant Nutrition |
Human milk fortifiers made from bovine
milk have been found to increase the incidence of necrotizing entercolitis
(NEC) in premature infants. Previous
research has shown that a human milk derived fortifier may reduce the chances
of NEC. Development of a simple process
for fractionating human milk could improve the health of premature infants by
providing a safe and wholesome protein source. The objective of this study was
to determine if the protein in banked human milk could be extracted with
greater than 80% recovery. Lipids from pasteurized (30 min, 62.5°C) human milk
were separated by centrifugation (10 min, 2000rpm, 4°C), followed by dialysis
(6-8 kDa) of the supernatant to remove lactose and other small molecular weight
molecules. The remaining protein fraction
was then freeze-dried (< 10 microns, 10°C) overnight. The result was a dried powder that can be
added to a mother’s own milk to enhance protein concentration. Samples of milk were taken prior to
processing, and after centrifugation, dialysis, and freeze-drying for protein
assay. Samples were also taken of the
lipid fraction and the buffer water from dialysis. Protein content was determined using the
bicinchoninic acid (BCA) protein assay.
Preliminary data indicated a 52.4% loss of proteins during
dialysis. Future research may include size-exclusion
chromatography or gel electrophoresis to determine if the protein loss was due
to dialysis membrane pore size. Although
a portion of human milk protein was successfully isolated, at this point the
process is not efficient enough to be employed on a larger scale.
|
McAdams, Callie P. |
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Department(s): |
Animal Science |
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Research |
Stephanie L. Hansen/Animal Science Jerry W. Spears/Animal Science |
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Title of Presentation: |
Severe Copper Deficiency Combined
with High Dietary Manganese Does Not Affect Bovine Prion Characteristics |
Copper (Cu) may play a role in normal
cellular prion protein function. Manganese (Mn) can act antagonistically to Cu
and exacerbate Cu deficiency. Bovine spongiform encephalopathy may be
associated with changes in brain Cu concentrations which may be lowered by high
Mn concentrations. This study analyzed the effects of Cu deficiency and the
effect of high dietary Mn on brain prion protein in cattle. Twenty-one Angus
calves were born to cows on study for a minimum of 410 days prior to calving
and were assigned to the same treatments as their dams. Treatments consisted
of: 1) Cu adequate (+Cu); 2) Cu deficient (-Cu); and 3) Cu deficient plus Mn
(-Cu+Mn). Calves were fed through a 136-day growing phase and a 139-day
finishing phase. Blood, liver, and brain obex samples were collected. Lower
liver Cu was seen in -Cu calves (6.9 mg/kg DM) compared to +Cu calves (208.4
mg/kg; P < 0.01). Plasma Cu was lower (P < 0.01) in -Cu (0.22 mg/mL)
versus +Cu (1.1 mg/mL); plasma Cu was also lower (P < 0.01) in -Cu+Mn (0.13
mg/mL) versus -Cu. Obex Cu was higher (P < 0.01) in the +Cu treatment (14.3
mg/kg) than in the -Cu treatment (3.6 mg/kg). There was also a tendency for
lower (P = 0.15) obex Cu in -Cu+Mn calves (1.9 mg/ kg) compared to -Cu. Obex Mn
concentration did not differ among treatments. ELISA and Western blotting
showed no differences in obex prion concentration due to dietary Cu. All
samples were completely digested by proteinase K. Copper chaperone protein
(CCS) levels in the obex of +Cu calves tended to be lower (P < 0.10) than in
-Cu calves. Extreme Cu deficiency was observed based on liver, plasma, and obex
Cu levels. Nevertheless, changes were not seen in brain prion protein
concentrations.
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Parnell, Courtney A. |
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Department(s): |
Animal Science |
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Research |
Vivek Fellner/Animal Science |
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Title of Presentation: |
Effect of Varying Soluble Carbohydrate
Levels on Microbial Fermentation |
The objective of this study was to
monitor the effects of soluble carbohydrate levels on fermentation by mixed
cultures of ruminal microbes. To assess fermentation differences we measured
methane, culture pH, and VFA pattern. A batch culture was conducted for a 6 h
interval using four different hay treatments that varied in percentages of
soluble carbohydrates (7, 11, 14, and 17%). Each time period had three bottles
per treatment to serve as a control. The bottles were all inoculated and placed
into a warm water bath to incubate for 0, 0.5, 1, 1.5, 2, 4, and 6 h. At the
end of each time period, the bottles were placed on ice to stop fermentation.
Each sample was analyzed for methane concentration, pH, and VFA. There seemed
to be a lag in methane concentration. It remained low for all treatments and
rapidly increased following 2 h of incubation. Treatments 1 and 2 averaged 676
and 678 nmol/ml, respectively and Treatments 3 and 4 averaged 790 and 740
nmol/ml, respectively. Culture pH ranged
from 6.62 to 6.50 at time 0 and gradually declined to 5.73 to 5.87 by the end
of 6 h. Numerically, treatment 3 had the lowest pH and greatest methane
concentration at 6 h. Total VFA production increased over time across all treatments.
At 6h, total VFA was reduced with an increase in soluble carbohydrate levels.
At 6 h, molar ratios of acetate were reduced and those of propionate increased
with an increase in soluble carbohydrate level. Changes observed with
increasing levels of soluble carbohydrate suggest a reduction in cellulolytic
activity. However, despite a consistent decrease in pH, methane concentration
increased with incubation time irrespective of the level of soluble
carbohydrates in the diet.
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Simmons, Kirsten A. |
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Department(s): |
Animal Science |
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Research |
Pam Hullinger/Lawrence Livermore
National Laboratory |
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Title of Presentation: |
Modeling Estimated Personnel Needs
for a Potential Foot and Mouth Disease Outbreak |
Foot and Mouth disease (FMD) is a highly
contagious viral disease affecting livestock that was last detected in the US
in 1929. The prevalence of FMD in other countries, as well as the current
potential for this virus to be used as a form of agroterrorism has made
preparations for a potential FMD outbreak a national priority. All 50 states
were surveyed via e-mail, telephone and web search to obtain emergency response
plans for FMD or for foreign animal diseases in general. Information from 35
states was obtained and analyzed for estimates of resources needed to respond
to an outbreak. These estimates were expanded and enhanced to create a
spreadsheet tool that could be used by individual states to better understand
the personnel that would be needed to complete various tasks during an outbreak
response. Personnel estimates were varied according to facility type and scaled
by size. The estimates were then coupled to the output from FMD outbreaks
simulated using the Multiscale Epidemiological/Economic Simulation and Analysis
(MESA) model at Lawrence Livermore National Laboratory to assess the personnel
resource demands on a response agency over the course of an outbreak
response.
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Sivamani, Durga |
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Department(s): |
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Research |
Shannon Shinault/Forestry and
Environmental Resources |
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Title of Presentation: |
An Analysis of Factors Impacting Two
Short-DistanceBird Migrant Species |
Changing photoperiod, the length of
the day, is a key factor in determining a species’ timing to migrate. Long-term
climate change, such as global warming, alters the photoperiod of the day by
making it longer. This causes the bird species confusion in timing when to
migrate. Our research project sought to investigate the factors behind the
increase and decrease respectively, in two short distance migrant bird species
populations, the Eastern Phoebe (Sayornis phoebe) and the Field Sparrow
(Spizella pusilla) over 30 years in North Carolina. Data obtained through the
Audobon Society’s Christmas Bird Counts indicated that although bird count
numbers fluctuated for both species, trend lines were able to be drawn. The
factors determining the trend lines involved habitat change and human
disturbance as well as general climate change. Overall, climate change played
an important role as a factor in determining the migration time for these two
short-distance migrant species.
|
Smith, Arianna L. |
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Department(s): |
Animal Science |
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Research |
Melissa S. Ashwell/Animal Science |
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Title of Presentation: |
Transcript Profiling of Testes from
Boars Divergently Selected for Testosterone Production |
Pork production is critical to the
North Carolina’s economy, as North Carolina is second in the nation for the
number of hogs and pigs. As a result, it
is important that scientific advances be utilized to increase swine production
efficiency. Testosterone production is
critical to reproductive success and high testosterone production has been
positively correlated to increased body growth (Bender et al., 2006). The objective of this research is to study
genes expressed in testes of pigs collected from lines divergently selected for
high versus low testosterone production.
Testes were harvested from pigs at 1, 30, and 120 days of age. RNA was extracted from all boars and microarrays
were used to determine genes showing differential expression between high and
low testosterone lines as well as changes in gene expression as the animals
age. The TIMP-1 gene was selected as a
gene of interest upon microarray analysis.
TIMP-1 regulates the extracellular matrix remodeling that occurs during
testicular maturation and stimulates steroidogenesis in Leydig cells. Real-time PCR is being used to examine TIMP-1
expression across lines and ages and data will be analyzed using the Pfaffl
method.
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Thames, Callie H. |
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Department(s): |
Animal Science |
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Research |
Gerald B. Huntington/ Animal Science |
|
Title of Presentation: |
Efficiency and Dry Matter
Digestibility in Beef Cattle |
Due to rapidly rising feed costs,
alternative methods are being researched to cut feed costs. Some beef cattle
naturally consume less feed without sacrificing growth and performance. If
animals with this trait can be identified, this trait can be selected for. A
variety of factors influence efficiency in beef cattle. The focus of this
particular study was to determine if there is a link between dry matter
digestibility and feed efficiency, as measured by the residual feed intake
technique. A digestion trial with twelve beef steers was conducted to create a
library of data to be used to predict efficiency of bulls. Fecal grab samples
from sixty bulls were collected during an eighty-four day test period. At the
conclusion of the digestion trial and the bull test, the two groups of samples
were compared. No correlation was found between dry matter digestibility and
residual feed intake. Although it seems that dry matter digestibility has very
little effect on efficiency, it does leave questions open to what factors do
have an effect on efficiency.
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