Clinical aspects of sentinel node biopsy

Sentinel lymph node (SLN) biopsy requires validation by a backup axillary dissection in a defined series of cases before becoming standard practice, to establish individual and institutional success rates and the frequency of false negative results. At least 90% success in finding the SLN with no more than 5-10% false negative results is a reasonable goal for surgeons and institutions learning the technique. A combination of isotope and dye to map the SLN is probably superior to either method used alone, yet a wide variety of technical variations in the procedure have produced a striking similarity of results. Most breast cancer patients are suitable for SLN biopsy, and the large majority reported to date has had clinical stage T1-2N0 invasive breast cancers. SLN biopsy will play a growing role in patients having prophylactic mastectomy, and in those with 'high-risk' duct carcinoma in situ, microinvasive cancers, T3 disease, and neoadjuvant chemotherapy. SLN biopsy for the first time makes enhanced pathologic analysis of lymph nodes logistically feasible, at once allowing greater staging accuracy and less morbidity than standard methods. Retrospective data suggest that micrometastases identified in this way are prognostically significant, and prospective clinical trials now accruing promise a definitive answer to this issue

Environmental Impact Of Beef Feedlot Cattle Feces, Urine, And Bedded Pack Facilities

University of Minnesota Ph.D. dissertation. March 2020. Major: Animal Sciences. Advisors: Alfredo DiCostanzo, Grant Crawford. 1 computer file (PDF); viii, 165 pages.Throughout the Upper Midwest, farmers have observed an increase in land prices and fertilizer prices resulting in the increased popularity of confinement feeding facilities such as mono-slope and hoop barns with bedded packs. Environmental and public pressure has been placed on the agriculture community to improve NH3, GHG, and VOC emissions from CAFOs. A study was conducted to determine the effect of bedding material (corn stover (CS), bean stover (BS), wheat straw (WS) or pine wood chips (PC)) and environmental ambient temperature (15°C (COLD) or 30°C (HOT)) on concentration of NH3, CH4, CO2, N2O, H2S, and odorous VOCs in air samples collected in headspace above lab-scaled bedded packs over a 42-d study. Bedded packs were housed in a common area at 18°C through Week 3 before being placed at their treatment temperature in respective environmental chamber. A significant (P = 0.0422) interaction between bedding material, ambient temperature and age of bedded pack was observed for CH4. Methane flux was similar across all treatments at Week 4. As bedded packs aged all the bedded packs in the cold chambers and the packs with the HOT-BS, HOT-PC, and HOT-WS treatment produced similar yet minimal flux compared to HOT-CS at Week 5. Whereas, at Week 6 HOT-BS and HOT-CS had significantly greater flux (10.48 and 12.59 mg m-2 hr-1; respectively) across all other treatments. A significant two-way interaction for bedding material by ambient temperature for NH3, H2S, and CO2, and N2O flux was observed (P = 0.0094, P < 0.0001, and P = 0.0005; respectively). Ammonia flux from BS, CS, and WS bedding material treatments was significantly greater at HOT ambient temperatures than COLD. Across all treatments significantly (P = 0.0407) greater NH3 flux (372.9 mg/m2/hr) was observed in headspace of HOT-WS bedded packs. Across all treatments COLD-BS had significantly (P < 0.0001) greater H2S flux than any other treatment, while bedding materials at HOT temperatures were similar. Carbon dioxide flux from WS bedding material was significantly (P < 0.05) greater no matter ambient temperature and increase over time. A significant (P = 0.0357) two-way interaction between ambient temperature and age of bedded pack for H2S flux was observed. Bedded packs maintained in COLD environments has similar H2S flux across weeks, while HOT treatments significantly (P = 0.0098) decreased from Week 4 to 6. Total aromatic compounds had significant (P = 0.0455) interaction for bedding material by ambient temperature as HOT were significantly greater than COLD across all bedding material types. An ambient temperature by age of bedded pack and bedding material by ambient temperature significant (P = 0.0008 and P = 0.0083)); respectively) interaction existed for total sulfide compounds as flux from COLD increase and HOT decrease over time. Total sulfides were the largest from PC bedded pack regardless of the temperature. Significant interactions for ambient temperature by age of bedded pack and bedding material by age of bedded pack was observed for both total BCFA and total SCFA. Total BCFA and total SCFA flux from CS and WS was significantly (P < 0.05) greater at Week 4, while total BCFA and total SCFA flux from HOT bedded packs decreased significantly (P < 0.05) from Week 4 to 5. Total OAVs decreases over time for both HOT and COLD treatments, although COLD treatments had significantly (P < 0.05) lower total OAVs regardless of age of bedded pack. Bedding types BS and PC had the lowest total OAV across all weeks. Aromatic compounds generated 72.0% of the total OAV over time. Producers should evaluate their bedded pack management system and consider potential bedding material being used and bedded pack removal frequency based on seasonal ambient temperatures to reduce overall operation flux emissions

Influence Of Feed Delivery Method, Supplement Moisture, And Access Time On Intake And Waste By Beef Cows

University of Minnesota M.S. thesis. April 2019. Major: Animal Sciences. Advisor: Alfredo DiCostanzo. 1 computer file (PDF); vii, 44 pages.A series of three 10-d experiments using a Latin Square design, was performed to determine whether hay processing and feeding method (Exp. 1), energy supplement moisture content and feeding method (Exp. 2) or access time to hay (Exp. 3) by late-gestating beef cows affected hay or supplement DMI and waste. In Exp. 1, large round bales were processed with a bale buster, to an average theoretical length of 12 cm, and delivered on the pen surface or in a bunk or left unprocessed and delivered in a hay ring or rolled out on the pen surface. In Exp. 2, corn screenings (CS) or wet beet pulp (BP) was fed in a structure (inverted tire or feed bunk) or on the pen surface (BP only). In Exp. 3, cows were permitted access to large round-bale hay in a hay ring for either 6, 14 or 24 h. In Exp. 1, hay DMI was not (P > 0.05) affected by hay processing or feeding method, and averaged 11.6 kg/d. Hay waste was greater (P = 0.0003) for cows fed hay on the pen surface (19.1%). In Exp. 2, hay DMI was greatest (P < 0.05) for cows fed no energy supplement and those fed CS in a bunk. Cows fed BP in a bunk wasted the most (P < 0.0001) hay (18.1%). In Exp. 3, DMI and waste was greatest (P < 0.0001) when cows had access to hay for 24 h. Cows allowed 6-h access to hay consumed and wasted less (P < 0.0001) hay compared to those given 14-h or 24-h access. In these experiments, cows fed hay on the pen surface achieved similar DMI as those fed in a structure, but wasted more hay. Delivering a high-moisture supple¬ment on the pen surface or bunk increased supplement or hay waste. Controlling access to hay reduced DMI and waste while maintaining cow BW

Use of bedding materials in beef bedded manure packs in hot and cool ambient temperatures: Effects on ammonia, hydrogen sulfide, and greenhouse gas emissions

Throughout the Upper Midwest, producers have observed increased land and fertilizer prices, resulting in increased popularity of confinement feeding facilities such as mono-slope and hoop barns with bedded packs. Environmental and public pressure has been placed on the agriculture community to reduce ammonia (NH3), hydrogen sulfide (H2S), and greenhouse gas (GHG) emissions from concentrated animal feeding operations (CAFOs). This study was conducted to determine the effects of bedding material (corn stover (CS), bean stover (BS), wheat straw (WS), or pine wood chips (PC)) and ambient temperature (15°C (COOL) or 30°C (HOT)) on NH3, CH4, CO2, N2O, and H2S flux in air samples collected in the headspace above lab-scale bedded packs. All bedded packs were housed at 18°C for an initial three weeks before being placed in their respective environmental chambers at 15°C or 30°C for the remainder of the 6-week study period. Significant two-way interactions of bedding material by temperature for NH3 flux were observed (p = 0.0094). Ammonia flux was greater at higher temperature, while CS bedding had the lowest NH3emissions compared to the other bedding materials. A significant two-way interaction of bedding material by temperature for H2S flux was observed (p \u3c 0.0001), with significantly greater H2S produced in the headspace of COOL-BS packs compared to all other treatments. Additionally, a significant (p = 0.0357) two-way interaction of temperature by age of the bedded pack was observed for H2S flux. Hydrogen sulfide flux appeared to be influenced by low bedded pack pH to a greater extent than by increase in temperature. Greenhouse gas emissions tended to be higher from bedded packs in HOT treatments. A significant (p = 0.0422) interaction among bedding material, temperature, and age of the bedded pack was observed for CH4. Significantly greater CH4flux was observed in the headspace above HOT-BS and HOT-CS at week 6 compared to all other treatments. A significant two-way interaction of bedding material by temperature was observed for CO2flux (p = 0.0189). The largest CO2levels were observed above WS bedding material regardless of temperature. Nitrous oxide flux decreased over the 6-week study for all bedded packs, while WS and PC bedded packs produced the greatest N2O flux. The results indicate that feedlot operators maintaining bedded pack facilities will have the greatest reduction in NH3emissions when using CS bedding, regardless of ambient temperature. To reduce CH4emissions, producers should avoid allowing BS and CS bedded packs that are maintained for longer than six weeks in HOT (30°C) temperatures; frequent cleaning during summer months is recommended. Based on the CO2equivalents of CH4and N2O, producers should consider PC as an option to reduce GHG emissions

Use of bedding materials in beef bedded manure packs at hot and cold ambient temperatures: Effects on odorous volatile organic compounds and odor activity values

Beef cattle producers are beginning to raise cattle in confinement facilities such as slatted-floor barns, hoop barns, and mono-slope facilities. Hoop and mono-slope facilities typically use bedding packs as part of their manure management system, with crop residues being the most commonly used bedding material. This study was conducted to determine the effects of bedding material, i.e., corn stover (CS), bean stover (BS), wheat straw (WS), or pine wood chips (PC), and environmental ambient temperature, i.e., cold (15°C) or hot (30°C), on the concentrations of odorous volatile organic compounds (VOCs) in air samples collected in the headspace above lab-scale bedded packs over a 42-day period. Total aromatic compounds, sulfide compounds, straight-chain fatty acids (SCFAs), and branched-chain fatty acids (BCFAs) were measured and used to calculate total odor activity values (OAVs) for each bedding and temperature effect. No significant three-way interactions for bedding material × ambient temperature × age of bedded pack were observed. Significant bedding material × ambient temperature interactions were observed for total aromatic compounds and total sulfide compounds (p = 0.0455 and p = 0.0083, respectively). The concentration of total aromatic compounds was greater for all hot treatments compared to cold treatments, with hot-CS and hot-WS bedding types (389.83 and 365.5 ng L-1, respectively) significantly (p \u3c 0.05) greater than all other bedding types, while total aromatic compounds were lowest (87.09 ng L-1) for BS across cold treatments. Total sulfide compounds from cold-PC (51.69 ng L-1) were significantly (p = 0.0143) greater than all other treatments. Within hot treatments, total sulfide compounds were similar across all bedding materials. Total SCFAs for both cold and hot treatments decreased significantly from weeks 4 to 6. Total SCFA concentrations within weeks were significantly (p \u3c 0.0001) greater for WS and CS compared to BS and PC but similar across bedding materials at week 6. Total BCFA concentrations from bedded packs containing CS and WS were significantly (p \u3c 0.0001) higher at week 4 compared to concentrations from bedded packs containing BS or PC. As bedded packs aged, total BCFA concentrations for all bedding materials were similar at week 6. Total OAVs decreased over time for both hot and cold treatments, although cold treatments had significantly (p \u3c 0.0001) lower total OAVs regardless of the age of the bedded pack. Aromatic compounds generated 72.6% of the total OAV over the 42-day study. Bedding types BS and PC had the lowest total OAVs across all weeks. The results indicate that feedlot operators maintaining bedded pack facilities will achieve the greatest overall odor reduction when using BS or PC bedding material, no matter the ambient temperature