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1.
Transl Anim Sci ; 2(1): 50-61, 2018 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-32289106

RESUMEN

Understanding how disease affects commercial production is imperative for pig producers to quantify its full impact on pig performance, carcass quality, and net returns. The objective of this experiment was to assess the productivity and economic importance of naturally occurring health challenges (HC) under commercial conditions. Three 1,000 pig grow-finish facilities received 936 pigs each. The experimental period started approximately 34 d post placement at an average start BW of 13.1 ± 0.2 kg. Barns were characterized based on the relative HC, determined by diagnostic assessments as the main characterization tool, along with other health indicators. Barns were characterized as low challenge health (LCh), moderate challenge health (MCh), and high challenge health (HCh). All barns tested positive for porcine reproductive and respiratory syndrome virus infection prior to the start of the experiment. Additionally, the MCh and HCh barns experienced influenza type A virus of swine. Similar to commercial production conditions, the disease challenge was not imposed but rather occurred naturally. Reduced ADG, ADFI, and G:F were observed with an increased HC (P < 0.001). Similarly, mortality was increased when the HC increased (P < 0.001). Decreased ADG increased days to achieve harvest BW, by 10 and 15 d in the MCh and HCh treatments compared with LCh, respectively (P < 0.001). No differences were observed for percent lean, loin depth, or fat depth (P > 0.10). The economic impact of the HC was assessed by applying these growth performance data to two economic models encompassing the two main marketing methods used by U.S. pig producers: fixed-weight and fixed-time. Financial losses attributed to the variation in disease severity that occurred in the present study ranged from $8.49 and $26.10 U.S. dollars (USD)/pig marketed using a fixed-market weight model, or between $11.02 and $29.82 USD/pig using a fixed-time model, depending on feed costs and market hog prices. In conclusion, increasing severity of HC under commercial conditions reduced ADG by 8% and 14% and resulted in mortality as high as 19.9%. Losses of $8.49 to $29.82/pig marketed underscore the potential magnitude of the economic impact of mixed etiology concurrent diseases in pork production.

2.
J Anim Sci ; 93(9): 4227-34, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26440321

RESUMEN

Significant attention perpetually surrounds possible changes in breeding herd inventories in the U.S. beef cattle industry. This article outlines economic considerations of U.S. herd expansion. Factors restricting expansion include land availability, increasing production efficiency, operator demographics, capital requirements, and commodity price volatility. Several offsetting factors support herd expansion including unprecedented cow-calf returns, ongoing global beef demand growth, and timing within the current cattle cycle. In addition to these industry-wide factors, several important variations in individual ranch considerations are outlined. The authors' expectations on future herd dynamics are provided, highlighting broader implications for individual operations, industry leaders, and the entire beef-cattle supply chain. The substantial economic impact and importance of the cow-calf sector warrants broader appreciation of these economic factors impacting herd expansion. The future size of the U.S. cattle industry is determined by the individual decisions of over 70,000 cattle owners, making this issue worthy of review by all industry stakeholders.


Asunto(s)
Crianza de Animales Domésticos/economía , Bovinos/genética , Bovinos/fisiología , Animales , Cruzamiento , Femenino , Estados Unidos
3.
Ophthalmology ; 106(2): 386-90, 1999 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-9951495

RESUMEN

OBJECTIVE: To assess the efficacy of latanoprost additive therapy in patients with intraocular pressure (IOP) out of control while taking maximum-tolerated medications and to determine whether pilocarpine therapy has a dose-dependent adverse effect on the efficacy of latanoprost therapy. DESIGN: Noncomparative case series. PARTICIPANTS: Sixty-one eyes of 61 patients with chronic glaucoma with IOP out of control while receiving maximum-tolerated medications were treated with latanoprost additive therapy on a compassionate basis. MAIN OUTCOME MEASURES: Follow-up was up to 22 months with a mean of 13.9 +/- 5.7 months. Kaplan-Meier survival analysis with Mantel-Cox log-rank test was performed to determine the overall success of latanoprost additive therapy and to compare the success rates of high-dose pilocarpine, low-dose pilocarpine, and no pilocarpine therapies. The criterion for success was avoiding glaucoma surgery with IOP decrease of 20% or greater and final IOP less than 22 mmHg. The IOP change and its significance for patients satisfying and failing the criterion for success also were determined to assess the latanoprost additive therapy. In addition, a number of pretreatment variables, including pilocarpine therapy, were analyzed for a significant effect on the efficacy of latanoprost additive therapy using Cox proportional hazards regression analysis. RESULTS: Latanoprost additive therapy significantly lowered mean IOP by 3.9 +/- 5.5 mmHg at 3 months and by 3.5 +/- 5.8 mmHg at 12 months. The cumulative success rate of the latanoprost additive therapy was 70% at 1 month, 42% at 3 months, 40% at 6 months, and 30% at 12 months. Of the variables studied, only increased number of previous incisional glaucoma surgeries and IOP greater than 24 mmHg before latanoprost additive therapy were significant prognostic factors for failure of latanoprost additive therapy. Pilocarpine therapy in any dose had no significant effect. CONCLUSION: This study supports a trial of latanoprost additive therapy before glaucoma surgery in patients with IOP out of control while receiving maximum-tolerated medications irrespective of pilocarpine therapy and the pilocarpine dosage, especially when the number of previous incisional glaucoma surgery is less than three and the IOP is less than 25 mmHg.


Asunto(s)
Glaucoma/tratamiento farmacológico , Presión Intraocular/efectos de los fármacos , Pilocarpina/uso terapéutico , Prostaglandinas F Sintéticas/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Relación Dosis-Respuesta a Droga , Sinergismo Farmacológico , Femenino , Estudios de Seguimiento , Humanos , Latanoprost , Masculino , Persona de Mediana Edad , Soluciones Oftálmicas/administración & dosificación , Soluciones Oftálmicas/uso terapéutico , Pilocarpina/administración & dosificación , Modelos de Riesgos Proporcionales , Estudios Prospectivos , Prostaglandinas F Sintéticas/administración & dosificación , Análisis de Supervivencia , Resultado del Tratamiento
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