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Full-Text Articles in Dairy Science

Functional Plain Yogurt Enhanced With Inulin And Aloe Vera, Janny Melissa Mendoza Mencia Apr 2018

Functional Plain Yogurt Enhanced With Inulin And Aloe Vera, Janny Melissa Mendoza Mencia

LSU Master's Theses

Yogurt has been recognized as a healthy food. Nutritional value of yogurt can be increased with the addition of aloe vera juice (AVJ) and inulin. People are interested in consuming products without artificial ingredients and with high content of bioactive compounds. The aims of this study were to develop a functional plain yogurt enhanced with inulin and AVJ, to evaluate the physicochemical properties, the enumeration of Streptococcus thermophilus and Lactobacillus bulgaricus, inulin content, and consumer acceptability. Six treatments were evaluated at day 1, 7, 14 and 30 at 4°C. Treatments were prepared using 2% fat milk, ABY culture, 5 …


Effects Of Dimethyl Sulfoxide And Glycerol Based Vitrification Protocols On Zona Pellucida Hardening In Mature Bovine Oocytes, Kaci Denise Rogers Apr 2018

Effects Of Dimethyl Sulfoxide And Glycerol Based Vitrification Protocols On Zona Pellucida Hardening In Mature Bovine Oocytes, Kaci Denise Rogers

LSU Master's Theses

Zona pellucida hardening is a natural process that occurs after oocyte fertilization to prevent polyspermic fertilization and to protect embryonic development. Pre-fertilization hardening of the zona pellucida however, decreases fertilization rates. Cryoprotectants have also been shown to negatively affect fertilization rates, one possible mechanism of which being through zona hardening. This experiment was conducted to determine the effect of different cryoprotectants on hardening of the zona pellucida using fresh mature bovine oocytes and vitrified mature bovine oocytes. Oocytes were post-slaughter from mixed breed cows. After collection, oocytes were randomly assigned to three cryoprotectant treatment groups: dimethyl sulfoxide (DMSO), glycerol or …


Influence Of "Added" Whey Protein Isolate On Probiotic Properties Of Yogurt Culture Bacteria And Yogurt Characteristics, Luis Alfonso Vargas Lopez Jan 2013

Influence Of "Added" Whey Protein Isolate On Probiotic Properties Of Yogurt Culture Bacteria And Yogurt Characteristics, Luis Alfonso Vargas Lopez

LSU Master's Theses

Consumers are becoming conscious of their diet, increasing protein intake and avoiding carbohydrates and fats. Whey proteins have branch chain amino acids responsible for muscle building. Whey protein isolate (WPI) contains more than 90% protein. The effect of incremental addition of WPI on probiotic characteristics of pure cultures and cultures in yogurt and yogurt characteristics are not known. The hypothesis was that “added” WPI will influence the characteristics of yogurt culture bacteria in pure form and in yogurt. The objectives were: to determine the influence of added WPI on (1) acid and bile tolerance, growth and protease activity of pure …


Influence Of "Added" Lactose On Probiotic Properties Of Yogurt Culture Bacteria And Yogurt Characteristics, Behannis Jasmin Mena-Chalas Jan 2013

Influence Of "Added" Lactose On Probiotic Properties Of Yogurt Culture Bacteria And Yogurt Characteristics, Behannis Jasmin Mena-Chalas

LSU Master's Theses

Lactose sugar is a source of energy for Lactic Acid Bacteria (LAB) in dairy fermented products. Enrichment of yogurt with lactose addition may increase growth and viability of the yogurt starter culture (Streptococcus thermophilus and Lactobacillus delbrueckii ssp. bulgaricus) and enhance yogurt physico-chemical and sensory attributes. The objectives of this study were: to determine the influence of added lactose on (1) acid and bile tolerance of yogurt starter culture Streptococcus thermophilus ST-M5 and Lactobacillus bulgaricus LB-12, (2) the final lactose content of yogurt during its shelf life, (3) the physico-chemical characteristics of yogurt during shelf life, (4) the growth of …


Influence Of Low Homogenization Pressures On Acid Tolerance, Bile Tolerance, Protease Activity, And Growth Characteristics Of Lactobacillus Delbrueckii Ssp Bulgaricus Lb-12, Streptococcus Salivarius Ssp Thermophilus St-M5, And Lactobacillus Acidophilus La-K, Tanuja Muramalla Jan 2010

Influence Of Low Homogenization Pressures On Acid Tolerance, Bile Tolerance, Protease Activity, And Growth Characteristics Of Lactobacillus Delbrueckii Ssp Bulgaricus Lb-12, Streptococcus Salivarius Ssp Thermophilus St-M5, And Lactobacillus Acidophilus La-K, Tanuja Muramalla

LSU Master's Theses

Lactobacillus delbrueckii ssp bulgaricus LB-12, Streptococcus salivarius ssp thermophilus ST-M5 and Lactobacillus acidophilus LA-K are dairy cultures widely used in the fermentation of dairy products. Homogenization is an essential process in dairy industry for making several products. High homogenization pressures (>50 MPa) are used to create stable emulsion, inactivate the pathogens and increase the protease activity of dairy cultures. Sparse literature is available on the influence of low homogenization pressures, and their effect on beneficial characteristics of dairy cultures is not well understood. The objective of this study was to determine the effect of low homogenization pressures on acid …


Dopaminergic Input To The Equine Pituitary: Seasonal And Estradiol Effects, Sarah Case Clavier Jan 2010

Dopaminergic Input To The Equine Pituitary: Seasonal And Estradiol Effects, Sarah Case Clavier

LSU Master's Theses

Two experiments were conducted to study the effects of season and estradiol administration on dopaminergic input to the equine adenohypophysis. Experiment 1 began in the spring with 8 mares and 8 stallions and was repeated again in the summer, fall, and winter. Horses were given sulpiride injections of eight incremental doses (0.25 to 32 µg/kg BW). Within each group of 8 horses, half received the sulpiride in an increasing manner, the other half in a decreasing manner. Prolactin concentrations peaked in the first 15 to 30 min in all horses in all seasons. Prolactin areas under the curve increased (P < 0.001) with increasing doses of sulpiride, and were highest (P < 0.05) in March for stallions, but in June for mares. The calculated half-maximum values, which should be proportional to the dopaminergic input to the pituitary, were lowest (P < 0.05) in June and greatest in September. The variation in half-maximum values with season indicated a change in dopaminergic input to the pituitary, with lowest input occurring in June in both sexes. Experiment 2 was designed to determine if the degree of dopaminergic input to the adenohypophysis is altered by estradiol administration. Twelve geldings were used. On day 0, geldings received an i.m. injection of either estradiol cypionate (ECP; n = 6) or vegetable oil (n = 6) at one of two dose volumes (2 vs. 10 mL). On day 6, all geldings received an injection of sulpiride at 0.082 µg/kg BW in saline. Sulpiride injections were repeated every other day with the dose increasing each day, from 0.164 to 100 µg/kg BW. Estradiol pretreatment increased (P < 0.05) the prolactin response to sulpiride at the 2.56 µg/kg dose and higher. However, the half-maximum values for ECP-treated and control geldings did not differ, indicating that the amount of sulpiride needed to counterbalance the amount of dopamine reaching the pituitary was unaltered by estradiol treatment. It was concluded that estradiol likely stimulates prolactin production and secretion after sulpiride directly at the lactotrope level, rather than by decreasing hypothalamic dopamine input to the lactotropes.


Effects Of Probiotics And Yeast Culture On Rumen Development And Growth Of Dairy Calves, Jennifer Marie Laborde Jan 2008

Effects Of Probiotics And Yeast Culture On Rumen Development And Growth Of Dairy Calves, Jennifer Marie Laborde

LSU Master's Theses

Forty-eight calves (heifers n=20, bulls n=28) were randomly assigned one of four dietary treatments which included no additive (C); the yeast culture Saccharomyces cerevisiae (YC); the probiotics Bacillus lichenformis and Bacillus subtilis (P); and both yeast culture and probiotics (YCP). Calves were administered treatments from day 2 to 56 in starter and from day 57 to 84 in grower diets. Body weights were measured at birth and weekly thereafter until day 112 of age. Wither and hip heights were measured weekly. Feed intake, water intake, and fecal scores were recorded twice daily until day 56. Rumen fluid was collected on …


Intracellular Lipids In Bos Indicus And Box Taurus Oocytes, Casey Bryant Ballard Jan 2007

Intracellular Lipids In Bos Indicus And Box Taurus Oocytes, Casey Bryant Ballard

LSU Master's Theses

It has been proposed that Bos indicus when compared with Bos taurus embryos are more sensitive to cryopreservation procedures due to higher intracellular lipid content of the embryos. With cyropreservation of Bos indicus embryos increasing for export, it is essential to improve the viability of these cryopreserved embryos. In Experiment I, M-II oocytes from mice, pigs and cows were subjected to two different procedures to evaluate lipid content. The lipid content present in pig oocytes was significantly (P<0.05) higher when compared with mouse and cow oocytes. Pig oocytes had a lower settling point in the sucrose buoyant density gradient and higher Nile Red units, which indicated higher lipids present in the oocytes. In Experiment II, it was determined that M-II oocytes aspirated from superstimulated Brahman donors were significantly higher (P<0.05) in lipid content compared with English breed donors. The lipid content present in Brahman oocytes was higher when compared with English breeds when tested with a sucrose buoyant density gradient and Nile Red staining. In addition, donor females with higher body condition scores were significantly (P<0.05) higher in oocyte lipid content when compared with donor females of lower body condition scores. Furthermore, animal body condition scores, cholesterol and triglyceride levels prior to oocyte aspiration may be indicators of intracellular lipids in the oocytes and embryos. To our knowledge, this is the first report that evaluated intracellular lipid content of M-II oocytes of different beef breed types using a sucrose buoyant density gradient and Nile Red staining.


A Novel Yogurt Product With Lactobacillus Acidophilus, Senthil Ganesh Jan 2006

A Novel Yogurt Product With Lactobacillus Acidophilus, Senthil Ganesh

LSU Master's Theses

Health benefits of Lactobacillus acidophilus include providing immune support for infections or cancer, providing a healthy replacement of good bacteria in the intestinal tract following antibiotic therapy, reducing occurrence of diarrhea in humans, aiding in lowering cholesterol and improving the symptoms of lactose intolerance. Consumer demand exists for new dairy products. There are several types of yogurt like stir curd, set curd and drinkable yogurt and they all need to be refrigerated. Moreover there are very few dairy products that can be stored at room temperature and not many dairy foods are finger foods. A novel yogurt product like a …


Comparing Calf Sex Ratio And Semen Sex Ratio Determined By Conventional Pcr, Tara Marie Taylor Jan 2005

Comparing Calf Sex Ratio And Semen Sex Ratio Determined By Conventional Pcr, Tara Marie Taylor

LSU Master's Theses

Thirty-nine ejaculates from 8 Holstein bulls were collected. Straws of semen (n=750) were distributed among dairies in three states. Ten straws per ejaculate were sent to Louisiana State University (LSU) Dairy Improvement Center for conventional polymerase chain reaction (PCR) analysis. Spermatozoal DNA was extracted and PCR analysis was done using one primer set amplifying a single copy 125 base pair (bp) section of the Bos taurus factor IX (Christmas factor) precursor (found on the X chromosome) and another primer set amplifying a single copy section of the Bos taurus sex determining region Y protein (SRY) gene (found on the Y …


Effects Of Protein Sources With Differing Ruminal Degradation Characteristics On Nutrient Digestibilities And Flows Through Various Segments Of The Gastrointestinal Tract Of Non-Lactating Holstein Cows, Taylor Whitney Braud Jan 2005

Effects Of Protein Sources With Differing Ruminal Degradation Characteristics On Nutrient Digestibilities And Flows Through Various Segments Of The Gastrointestinal Tract Of Non-Lactating Holstein Cows, Taylor Whitney Braud

LSU Master's Theses

Six non-lactating Holstein cows with ruminal and duodenal cannulas were used in a replicated 3x3 Latin square design experiment to investigate the effects of supplemental protein source on ruminal and total tract nutrient digestibility. Supplemental protein was provided from soybean meal (SBM), expeller processed soybean meal (EXP), or menhaden fish meal (FM). Basal diets consisted of (DM basis) 33% corn silage, 20% bermudagrass hay, 27% ground corn, and 2% minerals and vitamins. Supplemental protein was provided as (DM % of total diet) 18% soybean meal (SOY), 17% soybean meal and 1% fish meal (FM), or 12% soybean meal and 6% …


Characteristics Of Reduced Fat Milks As Influenced By The Incorporation Of Folic Acid, Kamalesh Achanta Jan 2005

Characteristics Of Reduced Fat Milks As Influenced By The Incorporation Of Folic Acid, Kamalesh Achanta

LSU Master's Theses

Folic acid plays an important role in the prevention of neural tube defects such as spina bifida and anencephaly, heart defects, facial clefts, urinary abnormalities and limb deficiencies. Milk and milk products serve as a potential source for folic acid fortification due to the presence of folate binding proteins which seem to be involved in the folate bioavailability. Though milk is a not a good source of folic acid, fortification could help in the prevention of the above mentioned defects. The objective of this study was to examine the physico-chemical characteristics of reduced fat milks fortified with folic acid. Reduced …


Efficacy Of Prepartum Intramammary Lactating Cow Treatment In Dairy Heifers, Christopher B. Norman Jan 2004

Efficacy Of Prepartum Intramammary Lactating Cow Treatment In Dairy Heifers, Christopher B. Norman

LSU Master's Theses

Mastitis in prepartum dairy heifers has been recognized as a significant economic problem for the dairy industry. Intramammary infusion of cephapirin sodium was completed in 20 treatment animals and the results were compared to 25 non-treated control animals. Bacteriological data from the quarter milk samples were used to determine and compare initial infection rates and cure rates following calving between treatment and control groups. Comparisons were also made between groups for differences in reproductive performance, milk yield, somatic cell count and milk ketone concentration. Milk yield did not differ between groups for either DHIA monthly average kg/day, 305 day actual …


Effects Of Dietary Protein Level And Fish Meal On Growth And Hormonal Status Of Weaned Dairy Calves, Patricia Terrell Richardel Jan 2004

Effects Of Dietary Protein Level And Fish Meal On Growth And Hormonal Status Of Weaned Dairy Calves, Patricia Terrell Richardel

LSU Master's Theses

Eight weaned Holstein steers approximately 4 mo of age (mean BW = 119.47 ± 2.65 kg) were used in a replicated 4 x 4 Latin square designed experiment to study the effects of protein source and level on performance and anabolic hormonal status of weaned dairy calves. Treatments consisted of two diets containing either 16 or 20 % crude protein (CP) with or without fish meal (FM). Experimental diets were corn silage based with soybean meal (SBM) as the source of ruminal degradable protein and FM as the source of ruminal undegradable protein. The animals were fed their respective diets …


The Effects Of Composition And Processing Of Milk On Foam Characteristics As Measured By Steam Frothing, Michael Levy Jan 2003

The Effects Of Composition And Processing Of Milk On Foam Characteristics As Measured By Steam Frothing, Michael Levy

LSU Master's Theses

Steam frothing of milk is required to produce an acceptable foam for many espresso coffee drinks. Specific aspects of composition and processing may affect the foaming properties of milk. The aim of this study was to determine the effect of fat content, heat treatment, free fatty acid addition and storage time on the frothing properties of milk. The four treatments included: fat content (0.08% and 3.25%), pasteurization temperatures (171°F for 15 seconds and 210°F for 45 seconds), pre and post-pasteurization addition of lauric acid solution (0.0% and 2.0% of 0.5 M concentration) and storage time (1 and 10 days). For …


Effects Of Free Methionine And Lysine On In Vitro Fermentation And In Vivo Performance And Ruminal Fermentation Of Late Lactation Holstein Cows, Yi-Hua Chung Jan 2003

Effects Of Free Methionine And Lysine On In Vitro Fermentation And In Vivo Performance And Ruminal Fermentation Of Late Lactation Holstein Cows, Yi-Hua Chung

LSU Master's Theses

Two experiments were conducted to investigate the effects of free Met and Lys supplementation on ruminal fermentation in vitro and in vivo. In the in vitro study, supplementation of Met and Lys had effects on concentrations of total VFA and NH4+, proportions of acetate, propionate, butyrate, isovalerate, valerate, and the ratio of acetate to propionate. Percentages of microbial N synthesis in effluent pellets were not affected by supplementing Lys and Met. The combination of 0.52% Met and 1.03% (90% DM) Lys resulted in the highest concentration of total VFA, second highest concentration of NH4+, …


The Effect Of Nocturnal Sampling On Semen Quality And The Efficiency Of Collection In Bovine Species, Jennifer H. Yates Jan 2002

The Effect Of Nocturnal Sampling On Semen Quality And The Efficiency Of Collection In Bovine Species, Jennifer H. Yates

LSU Master's Theses

The objective of this study was to evaluate two semen collection schedules utilizing the assumed behavioral differences between bovine species. The efficiency was measured by bull behavior and semen quality parameters. Four Holstein and four Brahman bulls were collected each during a morning and a night collection time weekly. Ejaculates (n=64) were obtained via artificial vagina over four-weeks. To avoid masking benefits of night collection, the first collection of the week was alternated between night and day. Two collection teams were employed to reduce the time needed for collection, and the variability in collection method. Sampling order and collection team …