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1.
Biol Rev Camb Philos Soc ; 95(6): 1838-1854, 2020 12.
Artículo en Inglés | MEDLINE | ID: mdl-32794644

RESUMEN

Biological control is widely successful at controlling pests, but effective biocontrol agents are now more difficult to import from countries of origin due to more restrictive international trade laws (the Nagoya Protocol). Coupled with increasing demand, the efficacy of existing and new biocontrol agents needs to be improved with genetic and genomic approaches. Although they have been underutilised in the past, application of genetic and genomic techniques is becoming more feasible from both technological and economic perspectives. We review current methods and provide a framework for using them. First, it is necessary to identify which biocontrol trait to select and in what direction. Next, the genes or markers linked to these traits need be determined, including how to implement this information into a selective breeding program. Choosing a trait can be assisted by modelling to account for the proper agro-ecological context, and by knowing which traits have sufficiently high heritability values. We provide guidelines for designing genomic strategies in biocontrol programs, which depend on the organism, budget, and desired objective. Genomic approaches start with genome sequencing and assembly. We provide a guide for deciding the most successful sequencing strategy for biocontrol agents. Gene discovery involves quantitative trait loci analyses, transcriptomic and proteomic studies, and gene editing. Improving biocontrol practices includes marker-assisted selection, genomic selection and microbiome manipulation of biocontrol agents, and monitoring for genetic variation during rearing and post-release. We conclude by identifying the most promising applications of genetic and genomic methods to improve biological control efficacy.


Asunto(s)
Comercio , Proteómica , Genómica , Internacionalidad , Sitios de Carácter Cuantitativo
2.
Indian J Med Microbiol ; 33(2): 243-7, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25865975

RESUMEN

INTRODUCTION: Studies have highlighted the advantages and disadvantages of woven and non-woven fabrics. The present study assessed the change in resterilisation proportion after introduction of non-woven fabric for packaging of instruments and to evaluate the cost-effectiveness of non-woven fabrics compared with woven fabrics. MATERIALS AND METHODS: The present study is a secondary data analysis of resterilisation data collected from November 2009 to August 2013. We calculated the proportions (and their 95% confidence intervals) of resterilisation done every month. The proportion over time was compared using a Chi-square test for trend. We used linear regression analysis to adjust for the number of surgeries performed every month. We also compared the cost of woven and non-woven fabrics. RESULTS: Of the total 117,335 surgical packets prepared during the study period, 1900 were resterilised; thus, the overall proportion was 1.62% (95% CI: 1.55% to 1.69%). The resterilisation proportion was 8.95% (95% CI: 7.73% to 10.17%) in November 2009 and was 0.38% (95% CI: 0.16% to 0.62%) in August 2013 (P < 0.001). After adjusting for the total number of surgeries conducted every month, we found that the number of packets resterilised reduced every month (per month reduction: -1.97, 95% CI: -2.76 to -1.18). The total cost (initial preparation and resterilisation) for 100 units of woven fabric is INR 6359.41 per month (confidence limit estimates: 6228.20 to 6430.62) and for non-woven fabric was INR 6208.50 (confidence limit estimate: INR 6194.90 to 6223.35) (P < 0.01). CONCLUSIONS: The introduction of non-woven spunbond-meltblown-spunbond fabrics did reduce the proportion of resterilisation of packaged instruments. The decline was sharp and sustained over time, even after accounting for the change in the number of procedures. Furthermore, though the switch from woven to non-woven fabric was cost-effective in our situation, it may not be directly translated to other scenarios.


Asunto(s)
Equipos y Suministros/microbiología , Embalaje de Productos/métodos , Esterilización/métodos , Costos y Análisis de Costo , Humanos , Embalaje de Productos/economía , Estudios Retrospectivos , Esterilización/economía
3.
Exp Appl Acarol ; 42(4): 263-71, 2007.
Artículo en Inglés | MEDLINE | ID: mdl-17634867

RESUMEN

Brevipalpus (Acari: Tenuipalpidae) mites are important pests on a variety of host plant species. The mites damage their hosts directly by feeding and some species also serve as vectors of plant viruses. Among more than 200 described Brevipalpus species, three are recognized as vectors of plant viruses: B. phoenicis, B. californicus and B. obovatus. These species occur worldwide in subtropical and tropical regions. Brevipalpus mites reproduce mostly by thelytokous parthenogenesis and this condition was attributed to a bacterial endosymbiont, recently characterized as a member of the genus Cardinium. The same symbiont infects many other arthropods and is capable of manipulating their host reproduction in various ways. Generally the presence of Cardinium is determined by molecular, PCR based, techniques. In the current work we present visual evidence for the presence of these bacteria by transmission electron microscopy as a complement of previous detection by PCR. Cardinium is easily identified by the presence of a unique array of microtubule-like structures (ML) in the cell. Symbionts have been observed in several organs and eggs from different populations of all three Brevipalpus species known as vector of plant viruses. Cardinium cells were always immersed directly within the cytoplasm of infected cells. Bacteria were observed in all females of all instars, but were absent from all males examined. Females from some Brevipalpus populations were observed to be uninfected by Cardinium. This observation confirmed previous PCR-based results that these populations were aposymbiotic. The observed distribution of the bacteria suggests that these bacteria could have other functions in the mite biology beside feminization.


Asunto(s)
Cytophagaceae/ultraestructura , Ácaros/microbiología , Simbiosis/fisiología , Animales , Cytophagaceae/fisiología , Femenino , Estadios del Ciclo de Vida , Microscopía Electrónica de Transmisión , Ácaros/ultraestructura , Óvulo/microbiología , Reacción en Cadena de la Polimerasa
4.
Exp Appl Acarol ; 39(3-4): 257-71, 2006.
Artículo en Inglés | MEDLINE | ID: mdl-16900311

RESUMEN

Bacterial symbionts that manipulate the reproduction of their host to increase their own transmission are widespread. Most of these bacteria are Wolbachia, but recently a new bacterium, named Cardinium, was discovered that is capable of the same manipulations. In the host species Brevipalpus phoenicis (Acari: Tenuipalpidae) this bacterium induces thelytoky by feminizing unfertilized haploid eggs. The related species B. obovatus and B. californicus are thelytokous too, suggesting that they reproduce in the same remarkable way as B. phoenicis. Here we investigated the mode of thelytokous reproduction in these three species. Isofemale lines were created of all three species and 19 lines were selected based on variation in mitochondrial COI sequences. All B. phoenicis and B. californicus lines (10 and 4 lines, respectively) produced males under laboratory conditions up to 6.7%. In contrast, males were absent from all B. obovatus lines (5 lines). Additional experiments with two B. phoenicis isofemale lines showed that males can be produced by very young females only, while older females produce daughters exclusively. For most lines it was shown that they are indeed feminized by a bacterium as treatment with antibiotics resulted in increased numbers of males up to 13.5%. Amplification and identification of specific gyrB sequences confirmed that those lines were infected with Cardinium. Three out of the five B. obovatus lines did not produce males after treatments with antibiotics, nor did they contain Cardinium or any other bacterium that might induce thelytoky. In these lines thelytoky is probably a genetic property of the mite itself. Despite the different causes of thelytoky, flow cytometry revealed that all 19 lines were haploid. Finally, the taxonomic inferences based on the mitochondrial COI sequences were incongruent with the classical taxonomy based on morphology, suggesting that a taxonomic revision of this group is necessary.


Asunto(s)
Bacteroidetes/fisiología , Ácaros/fisiología , Simbiosis , Animales , Bacteroidetes/genética , Femenino , Masculino , Ácaros/genética , Partenogénesis , Reproducción
5.
Exp Appl Acarol ; 36(3): 165-76, 2005.
Artículo en Inglés | MEDLINE | ID: mdl-16132731

RESUMEN

Because asexual species lack recombination, they have little opportunity to produce genetically variable offspring and cannot adapt to changes in their environment. However, a number of asexual species are very successful and appear to contradict this general view. One such species is the phytophagous mite Brevipalpus phoenicis (Geijskes), a species that is found in a wide range of environments. There are two general explanations for this pattern, the General Purpose Genotype (GPG) and Frozen Niche Variation (FNV). According to the GPG model, an asexual species consists of clones that can all survive and reproduce in all the different niches. Alternatively, the FNV model postulates that different clones are specialized to different niches. We have performed a test to distinguish between these models in B. phoenicis. Mites from three populations from three different host plant species (citrus, hibiscus and acerola) were transplanted to their own and the two alternative host plants and mite survival and egg production were measured. Additionally, the mite populations were genotyped using microsatellites. Fitness was seriously reduced when mites were transplanted to the alternative host plant species, except when the alternative host was acerola. We concluded that B. phoenicis clones are specialized to different niches and thus the FNV best describes the broad ecological niche of this species but that there is also some evidence for host plant generalization. This conclusion was strengthened by the observations that on each host plant species the native mite population performed better than the introduced ones, and that three microsatellite markers showed that the mite populations are genetically distinct.


Asunto(s)
Adaptación Fisiológica , Evolución Biológica , Ambiente , Reproducción Asexuada , Tetranychidae/genética , Tetranychidae/fisiología , Animales , Citrus/parasitología , Clima Frío , Conducta Alimentaria , Genotipo , Hibiscus/parasitología , Interacciones Huésped-Parásitos , Malpighiaceae/parasitología , Repeticiones de Microsatélite/genética , Oviposición/fisiología , Tasa de Supervivencia
6.
Environ Health Perspect ; 109(8): 779-84, 2001 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-11564612

RESUMEN

Use of elemental mercury in certain cultural and religious practices can cause high exposures to mercury vapor. Uses include sprinkling mercury on the floor of a home or car, burning it in a candle, and mixing it with perfume. Some uses can produce indoor air mercury concentrations one or two orders of magnitude above occupational exposure limits. Exposures resulting from other uses, such as infrequent use of a small bead of mercury, could be well below currently recognized risk levels. Metallic mercury is available at almost all of the 15 botanicas visited in New York, New Jersey, and Pennsylvania, but botanica personnel often deny having mercury for sale when approached by outsiders to these religious and cultural traditions. Actions by public health authorities have driven the mercury trade underground in some locations. Interviews indicate that mercury users are aware that mercury is hazardous, but are not aware of the inhalation exposure risk. We argue against a crackdown by health authorities because it could drive the practices further underground, because high-risk practices may be rare, and because uninformed government intervention could have unfortunate political and civic side effects for some Caribbean and Latin American immigrant groups. We recommend an outreach and education program involving religious and community leaders, botanica personnel, and other mercury users.


Asunto(s)
Cultura , Exposición a Riesgos Ambientales/análisis , Intoxicación por Mercurio/etnología , Mercurio/análisis , Religión , Adulto , Negro o Afroamericano , Contaminación del Aire Interior/análisis , Contaminación del Aire Interior/prevención & control , Conducta Ceremonial , Niño , Exposición a Riesgos Ambientales/efectos adversos , Exposición a Riesgos Ambientales/prevención & control , Hispánicos o Latinos , Humanos , Magia , Masculino , Medicina Tradicional , Mercurio/efectos adversos , Compuestos de Mercurio , Intoxicación por Mercurio/prevención & control , Óxidos , Medición de Riesgo/métodos , Control Social Formal/métodos , Estados Unidos , Volatilización
7.
Ambio ; 30(2): 104-11, 2001 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-11374307

RESUMEN

Through a case study on lead pollution in the former Soviet Union, the linkage of policy, environmental science, and environmental management is explored, and compared with the US experience. Soviet bans on leaded gasoline and lead-based paint appear to have been effective. Regional governments, in cooperation with the petroleum industry, are taking the initiative in phasing out leaded gasoline, to some extent in defiance of federal policy. Problems with management of lead-acid batteries have been worsened by the collapse of the political system. Lack of reliable environmental data impedes reliable environmental assessment. The types of environmental measurements reflect an emphasis on multipollutant environmental contamination, rather than on human exposure to single pollutants.


Asunto(s)
Contaminantes Atmosféricos , Contaminación del Aire/prevención & control , Monitoreo del Ambiente , Plomo , Humanos , U.R.S.S.
8.
J Am Vet Med Assoc ; 212(7): 997-1000, 1998 Apr 01.
Artículo en Inglés | MEDLINE | ID: mdl-9540871

RESUMEN

OBJECTIVE: To determine the effect of feeding vitamin E to ewes during late pregnancy on lamb mortality and ewe productivity. DESIGN: Prospective study. ANIMALS: 1,302 mature Rambouillet and Targhee ewes. PROCEDURE: During a 3-year period, approximately 430 ewes/y were randomly allocated to 2 groups; supplement-group ewes were fed additional vitamin E and control-group ewes were not. Beginning approximately 3 weeks before the first expected lambing date, ewes were fed 2.3 kg (5 lb) of alfalfa-grass hay/d and 0.23 kg (0.5 lb) of barley-based pellets/d with or without supplemental vitamin E. Pellets that were supplemented contained 1,450 mg of DL-alpha-tocopherol acetate/kg (658 mg/lb) of feed and provided an additional 330 IU of vitamin E/ewe/d. Selenium was incorporated into a trace mineral salt and fed free choice to all ewes throughout pregnancy. RESULTS: Supplemental vitamin E had no effect on ewe weight, body condition score, fertility, or prolificacy. In ewes that lambed in the early part of the lambing season, vitamin E supplementation significantly reduced lamb mortality, compared with no supplementation (12 vs 17%, respectively). Consequently, supplement-group ewes had significantly greater total body weight of lambs per ewe at the time of weaning, compared with control-group ewes. Differences were not observed between ewe groups in lamb mortality or total body weight of lambs per ewe at the time of weaning when ewes lambed during the late part of the lambing season. CLINICAL IMPLICATIONS: If ewes are fed additional vitamin E3 weeks before parturition, those that lamb in the early part of the lambing season may have low lamb mortality and, thus, higher total body weight of lambs per ewe at the time of weaning.


Asunto(s)
Animales Recién Nacidos/fisiología , Enfermedades de las Ovejas/mortalidad , Ovinos/fisiología , Vitamina E/administración & dosificación , Aumento de Peso/efectos de los fármacos , Animales , Animales Recién Nacidos/crecimiento & desarrollo , Suplementos Dietéticos , Femenino , Embarazo , Estudios Prospectivos , Enfermedades de las Ovejas/prevención & control , Vitamina E/farmacología , Vitamina E/uso terapéutico , Destete
10.
Environ Sci Technol ; 30(2): 82A-5A, 1996 Jan 29.
Artículo en Inglés | MEDLINE | ID: mdl-21648521

RESUMEN

Some attempts to balance atmospheric emissions of dioxins with deposition have suggested "missing sources." But the evidence disappears in the uncertainties in deposition data.

11.
J Anim Sci ; 73(10): 2853-9, 1995 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-8617653

RESUMEN

A 2-yr winter experiment was conducted to determine the influence of either energy or protein supplementation during midpregnancy on fecal output (FO), forage intake, blood metabolite profiles, and BW changes of ewes grazing winter range. Thirty-two Targhee ewes were selected for uniformity in age and BW and assigned randomly to one of four dietary treatments 1) no supplement (NONE); 2) 150 g of barley supplement (BAR); 3) 75 of feather g meal, blood supplement (FM/BM); and 4) 75 g of FM, BM, urea supplement (FM/BU/U). Two 5-d experimental periods were conducted during each winter (January and February). Forage FO (P = 0.9), total FO (P = 0.7), and subsequent forage intake (P < .01) were higher during Yr 1 than during Yr 2. Supplement type did not affect forage DMI when expressed either as grams/day (P = .57) or as a percentage of BW (P = .52). Body weight changes and body condition scores were not affected (P > .10) by year but were affected (P < .01) by treatment; unsupplemented ewes lost more (P < .01) BW and body condition than supplemented ewes. Serum urea N (SUN) concentrations were affected (P < .03) by a year x treatment interaction. Unsupplemented, FM/ BM, and FM/BM/U ewes had higher (P < .10) SUN concentrations during Yr 1 than during Yr 2, averaging 9.8 ml/dL and 7.5 mg/dL, respectively. Barley-supplemented ewes had similar (P > .10) SUN concentrations both years, averaging 7.4 mg/dL. Alternate-day supplementation during midpregnancy with energy of protein had no effect on forage DMI of ewes grazing winter range.


Asunto(s)
Alimentación Animal/normas , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía/fisiología , Preñez/fisiología , Ovinos/fisiología , Animales , Proteínas Sanguíneas/farmacología , Peso Corporal/fisiología , Fibras de la Dieta/administración & dosificación , Metabolismo Energético/fisiología , Femenino , Alimentos Fortificados , Hordeum/normas , Montana , Embarazo , Preñez/metabolismo , Distribución Aleatoria , Estaciones del Año , Ovinos/metabolismo , Urea/farmacología
12.
Environ Geochem Health ; 17(4): 200-10, 1995 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-24194292

RESUMEN

This preliminary investigation of sources of lead exposure in Moscow, Russia, by Russian and US collaborators measured lead in paint, interior dust, and drinking water in seven day-care centres, and in petrol, soil and canned food. Some paint samples exceeded US regulatory standards for lead in paint on surfaces (0.5%). Dust lead loadings were < 1.7 µg cm(-2) and below the guidance levels of the US EPA. Drinking water lead concentrations were at or below the US drinking water standard of 15 µg L(-1). Lead concentrations in petrol from Moscow vehicles and petrol stations were consistent with a regulation banning the sale of leaded petrol within the Moscow City limits. Except for baby food, lead levels were higher in the Russian canned foods (range 6 to 1240 µg kg(-1), dry weight) compared to corresponding US canned foods, with ratios of Russian to US levels of up to 120:1 for evaporated milk. Lead concentrations in soil generally ranged from 500 to 2000 µg g(-1), levels that would trigger hazard reduction measures according to US EPA guidance. These findings, together with the use of lead in petrol outside Moscow, indicate multiple sources of lead exposure in Russia. Priorities for future research are discussed including the establishment of interlaboratory quality control programmes.

14.
J Anim Sci ; 72(2): 509-14, 1994 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-8157538

RESUMEN

Our objective was to evaluate the effects of substituting feather meal (FM) for soybean meal (SBM) on ruminal fiber fermentation, lamb gain, blood metabolite profiles, and wool growth. A SBM supplement was formulated, and FM replaced either 33% (33FM), 66% (66FM), or 100% (FMS) of the SBM protein. Four ruminally cannulated wethers were used in a 4 x 4 Latin square design to study in situ ruminal digestion. Wethers were limit-fed barley straw and fed the supplements once daily. Ruminal NH3 N concentrations reflected a sampling time x protein source interaction (P < .01). Within sampling times, ruminal NH3 N concentrations decreased linearly (P < .05) as FM replaced soybean meal. Cubic (0 h; P < .10) and quadratic (24 h; P < .05) responses also were noted for ruminal NH3 N concentration. Substitution of FM for SBM had no effect (P > .10) on rate and extent of straw NDF disappearance. A 56-d feeding trial was conducted using 28 wether lambs (n = 7 per treatment; initial BW 32.3 kg). Wethers were individually fed chopped barley straw and one of the four supplements described previously. Linear increases (P < .05) in BW gain and serum total protein concentration were observed as FM replaced SBM. Wool fiber diameter and sulfur content did not differ (P > .10) among treatments. These data suggest that FM can be substituted for SBM in protein supplements fed to sheep consuming low-quality roughages at a maintenance level of ME intake.


Asunto(s)
Alimentación Animal , Fibras de la Dieta , Rumen/metabolismo , Ovinos/crecimiento & desarrollo , Lana/crecimiento & desarrollo , Amoníaco/análisis , Animales , Proteínas Sanguíneas/análisis , Proteínas en la Dieta/administración & dosificación , Proteínas en la Dieta/metabolismo , Digestión , Plumas , Fermentación , Hordeum , Concentración de Iones de Hidrógeno , Masculino , Distribución Aleatoria , Rumen/química , Glycine max , Aumento de Peso
15.
J Anim Sci ; 71(4): 1019-25, 1993 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-8478276

RESUMEN

Rambouillet wethers, surgically fitted with ruminal and duodenal cannulas, were used to determine the influence of substituting soybean meal (SBM) with blood meal (BM) in grass hay diets (8.0% CP) on N flow to the small intestine. Treatments were arranged in a 3 x 4 Latin square design and included diets (10.6% CP) supplemented with SBM; 2/3 SBM:1/3 BM; 1/3 SBM:2/3 BM; or BM. Ruminal NH3 N concentration decreased linearly (P = .03) as BM replaced SBM; however, feeding BM did not affect (P > .10) the total N, microbial N, or nonammonia N flows to the small intestine. A second experiment was conducted to determine the influence of substituting SBM with BM on ewe BW and condition score changes, blood metabolite profiles, wool growth, and progeny wool follicle development. Thirty-two pregnant Targhee ewes fed a grass hay diet were allotted randomly to four groups (n = 8) and supplemented with either SBM; 2/3 SBM:1/3 BM; 1/3 SBM:2/3 BM; or BM. Soybean meal, BM, or their combinations provided 22 g of dietary CP daily. Dietary treatments had no influence on ewe BW (P = .40) or body condition score (P = .77) changes, and ewes gained 7.6 kg of BW during the 84-d experiment. Protein source did not influence (P > .10) serum protein, urea N, creatinine, glucose, or nonesterified fatty acid concentrations. Lamb wool follicle density per square millimeter and secondary:primary follicle ratios were 22.4 and 10.8, respectively, and were not different (P > .10) among dietary treatments. Compared with SBM, no advantages were detected for BM supplementation of grass hay diets in these studies.


Asunto(s)
Proteínas en la Dieta/administración & dosificación , Nitrógeno/metabolismo , Preñez/fisiología , Ovinos/fisiología , Lana/crecimiento & desarrollo , Alimentación Animal , Animales , Proteínas en la Dieta/farmacocinética , Digestión , Femenino , Alimentos Fortificados , Tránsito Gastrointestinal , Absorción Intestinal , Intestino Delgado/metabolismo , Masculino , Estado Nutricional , Embarazo , Distribución Aleatoria , Ovinos/crecimiento & desarrollo
16.
Heart Lung ; 21(2): 180-6, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1544812

RESUMEN

Little is known of the needs of family members who provide home care to persons receiving ventilatory support (VS). In a structured interview of 44 care givers of 29 persons receiving VS, finances, provisions for emergencies, information, family relationships, and continuity of care were ranked as the most important needs. Needs for support services were ranked highest in importance to the care givers of persons receiving continuous VS, care givers who did not live in, and children of persons receiving VS. Parents of persons receiving VS ranked educational needs and attention to other family members of highest importance. Handling emergencies was most important to less experienced care givers, whereas financial and respite needs were more important to experienced and full-time care givers. Findings suggest the need for early participation of community health care professionals in care giver preparation, negotiations with third-party payers, 24-hour support services, information networks, and long-term, comprehensive coverage of services.


Asunto(s)
Cuidadores/psicología , Atención Domiciliaria de Salud/psicología , Respiración Artificial , Actividades Cotidianas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Escolaridad , Familia , Femenino , Humanos , Renta , Lactante , Masculino , Persona de Mediana Edad , Encuestas y Cuestionarios
17.
J Anim Sci ; 70(3): 640-5, 1992 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-1563991

RESUMEN

Ninety mature Targhee ewes were randomly allocated to nine lots. Lots were randomly assigned to three fleece preparation treatments: 1) nonskirted (control); 2) bellies removed, in which bellies and topknots were removed on the shearing floor; and 3) skirted, in which bellies and topknots were removed and remaining fleece was thrown on a table and lightly skirted. Bellies and topknots composed about 6 to 7% of the fleece weight. An additional 6.6% was removed when fleeces were skirted. Top fiber diameters were not affected (P greater than .10) by skirting. Although not significant (P greater than .10), percentage yield, vegetable content, percentage of noilage, top fiber length, and yellowness indexes tended to be most desirable for skirted lots and least desirable for unskirted lots. Lots with bellies removed were intermediate. Removal of bellies reduced vegetable contamination by 8.4%, with an additional reduction of about .5% by further skirting. Skirting reduced the number of fibers less than 25.4 mm (P less than .10) by 42%. Minimal colored fiber contamination of top was observed. One colored fiber per 15 g of top was detected in two lots of the treatment with bellies removed. All other lots contained no colored fibers. All wools evaluated were well below industry limits set for use in high-quality white or pastel fabrics. All skirted lots of wool evaluated in this study had improved processing characteristics for all processing traits evaluated.


Asunto(s)
Crianza de Animales Domésticos/métodos , Ovinos/anatomía & histología , Lana/normas , Animales , Cruzamiento , Femenino , Distribución Aleatoria , Estados Unidos , Lana/anatomía & histología , Lana/economía
18.
J Anim Sci ; 70(1): 273-80, 1992 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-1582914

RESUMEN

Two experiments were conducted to evaluate effects of supplemental protein source and ME intake (Exp. 1) on ewe nutritional status during pregnancy. Forty-two mature Targhee ewes were allotted randomly in Exp. 1 to one of six treatments (n = 7) using a 2 x 3 factorial arrangement. Ewes were individually fed chopped barley straw and supplements containing either urea (U), soybean meal (SBM), or blood meal (BM) plus SBM during the 84-d experiment. Straw and supplement intakes were adjusted to meet either 80 or 100% of ME requirements. In Exp. 2, 30 pregnant Targhee ewes that were allotted randomly to one of three groups (n = 10) were individually fed protein supplements similar to those in Exp. 1 and had group access to long-stem barley straw. In Exp. 1, ewes fed BM + SBM gained more (P less than .05) weight, lost less (P less than .05) body condition, and had increased (P less than .05) wool fiber length compared with ewes fed U; SBM ewes were intermediate (P less than .05) in response. Ewes fed BW + SBM had increased (P less than .05) blood urea N and albumin concentrations compared with ewes fed U. Metabolizable energy intake did not affect (P greater than .05) ewe performance or serum metabolite concentrations. Ewes fed BM + SBM in Exp. 2 gained more (P less than .05) weight than ewes fed either SBM or U, and ewes fed SBM lost less weight (P less than .05) than ewes fed U.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Fenómenos Fisiológicos Nutricionales de los Animales , Proteínas en la Dieta/administración & dosificación , Ingestión de Energía , Preñez/metabolismo , Ovinos/metabolismo , Alimentación Animal , Animales , Peso al Nacer , Sangre , Proteínas Sanguíneas/análisis , Nitrógeno de la Urea Sanguínea , Peso Corporal , Metabolismo Energético , Femenino , Alimentos Fortificados , Estado Nutricional , Embarazo , Distribución Aleatoria , Rumen/microbiología , Albúmina Sérica/análisis , Ovinos/crecimiento & desarrollo , Glycine max , Urea/administración & dosificación , Destete , Lana/crecimiento & desarrollo
19.
J Anim Sci ; 68(6): 1530-5, 1990 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-2384354

RESUMEN

Two winter feeding trials (1985-86; 1986-87) were conducted to evaluate the productivity of gestating ewes fed lasalocid (L) and two supplement levels while grazing Montana winter range. Five hundred range ewes were randomized within age and breed each year and allotted to .15 or .23 kg hd-1.d-1 of a 20% CP supplement and either no L or L at 70 mg hd-1.d-1. Feed treatments began on 18 Dec. approximately 100 d before the first expected lambing date and continued for 84 d. Ewes fed .23 kg of supplement per day gained more (P less than .01) total weight (4.9 vs 4.0 kg) during the 84-d experiment and had higher (P less than .05) grease fleece weights (4.2 vs 4.0 kg) than those fed .15 kg of supplement. Lasalocid had no effect (P greater than .05) on ewe weight change or grease fleece weights. Supplement level had no effect (P greater than .05) on reproduction, lamb mortality and lamb performance. Ewes fed L had a greater (P less than .05) percentage of lambs born per ewe than those not fed L (120.7 vs 112.1%); lamb performance was similar (P greater than .05) between treatments. However, because a greater percentage of lambs were born per ewe starting the experiment, ewes fed L produced more (P less than .05) kilograms of weaned lamb than those not fed L (25.9 vs 23.4 kg). In conclusion, ewes fed L and grazing winter range weaned more kg of lamb than did controls because of an improved lambing percentage.(ABSTRACT TRUNCATED AT 250 WORDS)


Asunto(s)
Alimentación Animal , Animales Recién Nacidos/crecimiento & desarrollo , Alimentos Fortificados , Lasalocido/farmacología , Preñez/fisiología , Ovinos/fisiología , Animales , Peso Corporal/efectos de los fármacos , Femenino , Análisis de los Mínimos Cuadrados , Embarazo , Preñez/efectos de los fármacos , Distribución Aleatoria , Estaciones del Año , Ovinos/crecimiento & desarrollo , Lana/crecimiento & desarrollo
20.
Theriogenology ; 29(4): 961-70, 1988 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-16726417

RESUMEN

Semen and blood samples from 154 rams from two Montana range flocks (Flock A, vaccinated for Brucella ovis ; Flock B, nonvaccinated) were evaluated to determine the relationship between Brucella ovis (B. ovis ) semen culture results and various semen and blood parameters. All rams utilized in this study exhibited no palpable ram epididymitis lesions. Thirteen and 25.6% of the rams tested in Flocks A and B, respectively, had positive B. ovis semen cultures. Only age of ram and ram condition scores differed (P<0.05) between flocks. No flock by semen culture interactions were detected (P>0.05) for any of the parameters evaluated. Age of ram, ram condition score, and spermatozoa rate from forward movement were unrelated (P>0.05) to B. ovis culture results. Rams with positive B. ovis semen cultures had lower sperm motility (P<0.05), higher percentage of abnormal spermatozoa cells (P<0.05), higher percentage of spermatozoa head abnormalities (P<0.01), lower percentage of live-normal cells (P<0.05), higher incidence of white blood cells in semen (P<0.01) and higher complement fixation (CF) titers (P<0.01).

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