The spread of tetracyclines through agricultural systems is causing the present bacteria to develop antibiotic resistance. The spread of this bacteria, as well as the tetracycline antibiotics in the environment is dangerous because these antibiotics pose health hazards for humans. The overuse of antibiotics, which are added to livestock feed, results in the antibiotics being released into the environment via animal feces. In this research, we have attempted to design an analytical method to isolate antibiotics from agricultural wastes with subsequent detection using liquid chromatography and mass spectrometry (LC-MS). The antibiotics investigated in this study were tetracycline, chlortetracycline, and oxytetracycline. The analytical procedure involves mixing the agricultural samples with an organic solvent, such as methanol, which solubilizes these antibiotics. Next, samples are centrifuged to remove solid particulates. A polymeric weak cation cartridge was used to concentrate and separate the antibiotics from the unwanted organic chemical compounds found in the samples. The antibiotics were released with methanol with small amounts of acid and then detected and quantified using LC-MS and high performance liquid chromatography with a photodiode array detector (HPLC-PDA).

Pigs farrowed and reared in metal farrowing stalls were studied to determine the need for iron. Three treatments were studied, namely—T-O (pigs given no iron injection), T-1 (pigs given 1 iron-dextran injection at 2 days of age) and T-2 (pigs given 2 injections of iron-dextran, the first at day 2 and the second at day 7). Hemoglobin levels were analyzed to determine the incorporation of iron in the bloodstream in the form of hemoglobin. Pig weights were used as a measure of production. The hemoglobin levels did not differ (p>0.1) among the 3 treatments at birth, 4 days, 6 days, 2 weeks and 5 weeks of age. However, birth values were higher (p<0.01) than either 4 or 6 day values. In addition, 2 week values were higher (p<0.01) than 4 and 6 day values, but lower than birth values. Five week values were the highest (p<0.01) of all values measured. Weights did not differ among treatment groups at 2 and 5 weeks of age (p>0.1). Results of this study indicate that pigs farrowed and reared in metal farrowing stalls neither benefit in iron level or production from iron-dextran injections.

The purpose of this study was to compare the performance and carcass characteristics of swine of four different phenotypes and three USDA grades. Hogs were placed into phenotypic groups of 24 each and penned by group. These pens were ideal, cutability, light muscled, fat, VS US and US The hops were fed a 16% corn and soybean meal ration fortified with appropriate minerals and vitamins. They were housed in a total confinement curtain-sided Kentucky plan building with a partially slatted floor. The hogs were weighed at 6-week intervals throughout the project to monitor average daily gain and pen feed efficiency. Twelve hogs from each pen were slaughtered at approximately 2(0 pounds and the remaining twelve pigs at approximately 230 pounds to determine if differences in performance and carcass characteristics remained consistent or became greater at heavier weights. Carcass weight, backfat at the tenth rib and last rib, length and loin eye area were obtained on each carcass. Data were adjusted to the group means for the heavy and light groups using least squares analysis. The mean for the heavy group was 255 pounds and the mean for light group was 229 pounds. Results of the study showed the ideal pen to have significantly higher (P<.01) average daily gain than all other pens at 229 pounds and significantly higher (P<.01) average daily gain than the cutability, US #2, and US #3 pens at 255 pounds. The two leanest and heaviest muscled pens were cutability and US #1. These two pens had significantly (P<.01) lower fat and larger loin eye area than the light muscled. US #3 and fat pens at 229 pounds. The fat pen had significantly (P.-01) greater backfat, smaller loin eye area, and lower percent muscle than all other pens in the heavy group. The cutability and US #1 pens had significantly higher (P<.01) percent muscle than the light muscled, US #3, and fat pens. The ideal, US #1, and cutability pens had significantly (P<.01) higher lean gain per day on test than all other pens with the exception of the light muscled pen taken to the heavier slaughter weight. The ideal, cutabilitv, and US #1 hogs had the lowest average values for feed per unit of lean gain. The fat pen required 2.5 pounds more feed to produce a pound of loan gain than ideal. cutability or US #1 pens. The US #1 group required 1.50 fewer pounds of feed per pound of lean growth than US #2 and #3 groups. These results indicate that the ideal pen was superior in terms of performance and lean growth. The cutabilitv and US #1 pen were the leanest and heaviest muscled. The fat group was extremely high in backfat, low in loin eye area and the most inefficient in converting feed into lean tissue.

Consumer evaluation, proximate data, Warner-Bratzler shear force (WBSF), fatty acid (FA) composition and volatile compounds were analyzed from the Longissimus thoracis (LT), Tricep brachii (TB) and Gluteus medius (GM) muscles finished on conventional feedlot (FL) and forages, including a perennial legume, birdsfoot trefoil (BFT; Lotus corniculatus), and a grass, meadow brome (Bromus riparius Rehmann, Grass). Representative retail forage (USDA Certified Organic Grass-fed, COGF) and conventional beef (USDA Top Choice, TC) were investigated (n = 6) for LT. Additionally, the effects of diet on Gluteus medius (GM) and Tricep brachii (TB) muscles were explored. Forage-finished beef scored lower (P < 0.05) in most of the affected sensory attributes except BFT which was similar to grain-finished beef. In forage-finished beef GM was more liked and in FL, TB was similar to GM except juiciness where it scored greater. The fat percent was found to be greatest (P < 0.05) in TC followed by BFT and FL. Nutritionally beneficial ratios of FAs were observed in forage-finished diet. Fatty acid concentrations were majorly affected (P ≤ 0.046) by diet. Few long-chain PUFAs were affected (P ≤ 0.015) by muscle type. No FA was a effected (P > 0.05) by the interaction of muscle and diet. 3-hydroxy-2-butanone, known to evoke a buttery sensation was affected (P = 0.011) by diet with greater (P < 0.05) concentration in GM across all diets. Strecker degradation products were affected (P ≤ 0.014) by muscle type being prominent in GM. Meanwhile, 2-ethyl-3,5-dimethyl-pyrazine was greatest (P < 0.05) in BFT. All pyrazine compounds were (P < 0.05) greater in GM. These results indicate that when consumer evaluated beef of finishing diets, FL beef was rated highly. Additionally, not all forages produce similar beef. There were similar ratings for BFT for all attributes except flavor having lower values compared with FL. The chemical composition of BFT beef was found to be intermediary and similar to both FL and Grass beef in many cases. Diet was found to interact with muscle for sensory and chemical measures. The GM and TB of FL did not differ (P < 0.05), while within forage treatments sensory response and chemical composition varied. These results indicate the meat quality of secondary beef muscles is more greatly impacted by forage diets.

Sub-zero saline solutions were evaluated for the improvement of chilling efficiency and product quality of broiler carcasses. In this study, four experiments were conducted to chill broiler carcasses using different saline solutions and chilling temperatures in the Meat Processing Center at California Polytechnic State University (Cal Poly, San Luis Obispo, CA) or in the processing plant at Foster Farms (Livingston, CA). In Experiment I, three salt concentrations and solution temperatures (0% NaCl/0.5°C, 4% NaCl/-2.41°C, and 8% NaCl/-5.08°C) were used to chill carcasses. The fillets in brine chilling at sub-zero temperatures showed lower shear forces than the fillets in 0% NaCl control solution. In Experiment II, three salt concentrations (0% NaCl/0.5°C, 4% NaCl/-2.41°C, and 8% NaCl/-5.08°C) were used to chill carcasses with/without pre-chilling in 0% NaCl/0.5ºC or 0% NaCl/14°C. Fillets from the carcasses in 4% NaCl/-2.41°C significantly improved tenderness (P < 0.05), with no significant difference observed for the shear force of 8% NaCl/-5.08°C, regardless of pre-chilling. In Experiment III, four salt concentrations (0% NaCl/0.5°C, 1% NaCl/-0.6°C, 2% NaCl/-1.2°C, and 3% NaCl/-1.8°C) were used to chill carcasses. The shear force of fillets decreased as the salt content increased and chilling temperature decreased from 0%NaCl/0.5°C to 3%NaCl/-1.8°C, with the lowest shear force observed in 3% NaCl brine at -1.8°C (P < 0.05). The chilling time (90 min) of 3% NaCl was reduced by 25 min (or 22%) compared to water control (115 min), with an intermediate reduction (13 - 17%) v seen for other NaCl solutions (95 – 100 min). Breast fillets showed no significant difference in chilling yield, pH, R-value, and sarcomere length for raw meats as well as in cooking yield and salt content for cooked fillets across all treatments (P > 0.05). In Experiment IV, three salt concentrations (0% NaCl/0.5°C, 3% NaCl/-1.8°C, and 4% NaCl/-2.41°C) were used to chill carcasses. The chilling time (55 min) of 4% NaCl was reduced by 35 min (or 39%) compared to the time (90 min) of water control, with an intermediate reduction (11%) seen for 3% NaCl solution. Control fillets in 0% NaCl showed a higher shear force than the fillets in sub-zero brine chilling (P < 0.05). Based on these results, broiler carcasses chilled in 4% NaCl/-2.41°C appears to be ideal to improve both chilling efficiency and meat tenderness compared to the carcasses chilled in 0% NaCl/0.5°C.

Processed meats have received negative publicity due to high fat contents that have been linked to adverse effects on human health. Fat is an essential ingredient in many processed meat products, so reducing this all while maintaining the desired characteristics of the product is a challenge. The purpose of this study was to generate low-fat meat products using a combination of hot-boning/crust-freeze-air-chilling (HB-CFAC) and cold-batter mincing (CBM) technologies. Pork hams were subjected to HB-CFAC or chill-boning/crust-freeze-air-chilling (CB-CFAC) prior to 3 min pre-mincing and 6 min mincing for control gels with back-fat addition or low-fat gels with water addition instead of the reduced back-fat. Raw meat quality, protein functionality and textural properties were analyzed through various analyses. The pH values of HB muscle and cooked gels were significantly higher than those of CB muscle and cooked gels. The fat and moisture contents of control gels was higher and lower, respectively, than those of low-fat gels, regardless of HB or CB. The protein functionality and gel forming ability of HB muscle were superior to those of the CB muscle, regardless of fat content. These results indicate that fat can be reduced with no loss of textural quality because cold-batter mincing of the HB-CFAC muscle resulted in higher gel forming ability than that of CB-CFAC muscle.

No description available.

This study examined the effects of electrical stimulation on water-soluble flavor compounds in beef semimembranosus muscle, collected immediately after exsanguination (PRE), immediately after stimulation (POST), and 24 h postmortem (H24) from both stimulated (ES) and non-stimulated (CON) carcasses. Short-chained peptides were greater in ES at H24 (P = 0.007). Glutamic acid concentration was above its taste threshold (0.044 mmol/kg) and was less in ES at PRE and POST by 0.030 mmol/kg (P ≤ 0.028) but was similar in both ES and CON by H24 (P = 0.142). Lysine, a Strecker amino acid, was greater in ES at H24 by 0.138 mmol/kg (P = 0.002). Adenosine triphosphate and adenosine 5’-monophosphate were greater in CON at both POST and H24 (P < 0.001). Inosine 5’-monophosphate was greater at H24 in CON (P < 0.001) than in ES. Electrical stimulation may negatively impact beef flavor by increasing bitter peptides and decreasing umami-enhancing nucleotides.

<p dir="ltr">This research thesis focuses on natural postmortem strategies for improving fresh meat quality. More specifically, it focuses on fresh meat tumbling application in beef and dry-aging methods in bison.</p>

The effects of dietary ingredients on the proteome profile of postmortem beef longissimus lumborum (LL) muscle were evaluated. In the first experiment, the influence of dietary ractopamine on the whole-muscle proteome of beef LL was examined. Five proteins were differentially abundant between ractopamine-fed (RAC) and non-ractopamine fed (CON) groups. The differentially abundant proteins were over-abundant in RAC and were related to muscle structure development (F-actin-capping protein subunit beta-2 and PDZ and LIM domain protein-3), chaperone (heat shock protein beta-1), oxygen transportation (myoglobin), and glycolysis (L-lactate dehydrogenase A chain). These findings indicated that ractopamine influences the abundance of proteins associated with muscle structure and fiber type shift in beef LL. In the second experiment, the effect of Vitamin E supplementation on the sarcoplasmic proteome of beef LL was characterized. Five differentially abundant proteins were observed between vitamin E-supplemented (VITE) and non-vitamin E-supplemented (CONT) groups. All the differentially proteins were over-abundant in CONT and were associated with antioxidant activity (thioredoxin-dependent peroxide reductase, peroxiredoxin-6, and serum albumin) and glycolysis (beta-enolase and triosephosphate isomerase). These results indicated that the strong antioxidant activity of vitamin E leads to low expression of antioxidant proteins and antioxidant-related glycolytic enzymes in beef LL muscle.