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1.
Rhinology ; 62(3): 330-341, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38189480

RESUMEN

BACKGROUND: In this study, we identified key discrete clinical and technical factors that may correlate with primary reconstructive success in endoscopic skull base surgery (ESBS). METHODS: ESBS cases with intraoperative cerebrospinal fluid (CSF) leaks at four tertiary academic rhinology programs were retrospectively reviewed. Logistic regression identified factors associated with surgical outcomes by defect subsite (anterior cranial fossa [ACF], suprasellar [SS], purely sellar, posterior cranial fossa [PCF]). RESULTS: Of 706 patients (50.4% female), 61.9% had pituitary adenomas, 73.4% had sellar or SS defects, and 20.5% had high-flow intraoperative CSF leaks. The postoperative CSF leak rate was 7.8%. Larger defect size predicted ACF postoperative leaks; use of rigid reconstruction and older age protected against sellar postoperative leaks; and use of dural sealants compared to fibrin glue protected against PCF postoperative leaks. SS postoperative leaks occurred less frequently with the use of dural onlay. Body-mass index, intraoperative CSF leak flow rate, and the use of lumbar drain were not significantly associated with postoperative CSF leak. Meningitis was associated with larger tumors in ACF defects, nondissolvable nasal packing in SS defects, and high-flow intraoperative leaks in PCF defects. Sinus infections were more common in sellar defects with synthetic grafts and nondissolvable nasal packing. CONCLUSIONS: Depending on defect subsite, reconstructive success following ESBS may be influenced by factors, such as age, defect size, and the use of rigid reconstruction, dural onlay, and tissue sealants.


Asunto(s)
Pérdida de Líquido Cefalorraquídeo , Endoscopía , Procedimientos de Cirugía Plástica , Base del Cráneo , Humanos , Femenino , Masculino , Base del Cráneo/cirugía , Pérdida de Líquido Cefalorraquídeo/etiología , Pérdida de Líquido Cefalorraquídeo/prevención & control , Pérdida de Líquido Cefalorraquídeo/epidemiología , Estudios Retrospectivos , Persona de Mediana Edad , Endoscopía/métodos , Procedimientos de Cirugía Plástica/métodos , Adulto , Complicaciones Posoperatorias/prevención & control , Complicaciones Posoperatorias/epidemiología , Anciano , Neoplasias Hipofisarias/cirugía , Neoplasias de la Base del Cráneo/cirugía , Rinorrea de Líquido Cefalorraquídeo/prevención & control , Rinorrea de Líquido Cefalorraquídeo/cirugía , Rinorrea de Líquido Cefalorraquídeo/etiología
2.
Multivariate Behav Res ; 56(4): 608-626, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32324059

RESUMEN

Several structural equation modeling estimation methods have recently been developed to alleviate problems associated with model misspecification. Two of the more popular such approaches are 2-stage least squares and regularization methods. Prior work examining the performance of these estimators has generally focused on problems with adequately sized samples and relatively large factor loadings. In contrast, relatively little research has been conducted comparing these estimation techniques with small samples and weak loadings, though both conditions are not uncommon in the multivariate modeling. The current simulation study focused on comparing these relatively new structural estimation methods for misspecified models (e.g., misspecified interactions and cross-loadings) with small samples and relatively weak factor loadings. Results indicated that regularized 2-stage least squares estimation performed better compared to the regularized structural equation modeling framework for small samples and with weak factor loadings. Implications and guidelines for applied researchers are presented.


Asunto(s)
Modelos Estadísticos , Simulación por Computador , Análisis de Clases Latentes , Análisis de los Mínimos Cuadrados , Funciones de Verosimilitud
3.
Anim Genet ; 51(2): 330-335, 2020 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-31900974

RESUMEN

Resistance to gastrointestinal nematodes has previously been shown to be a moderately heritable trait in some breeds of sheep, but the mechanisms of resistance are not well understood. Selection for resistance currently relies upon faecal egg counts (FEC), blood packed cell volumes and FAMACHA visual indicator scores of anaemia. Identifying genomic markers associated with disease resistance would potentially improve the selection process and provide a more reliable means of classifying and understanding the biology behind resistant and susceptible sheep. A GWAS was conducted to identify possible genetic loci associated with resistance to Haemonchus contortus in Katahdin sheep. Forty animals were selected from the top and bottom 10% of estimated breeding values for FEC from a total pool of 641 sires and ram lambs. Samples were genotyped using Applied Biosystems™ Axiom™ Ovine Genotyping Array (50K) consisting of 51 572 SNPs. Following quality control, 46 268 SNPs were included in subsequent analyses. Analyses were conducted using a linear regression model in plink v1.90 and a single-locus mixed model in snp and variation suite. Genome-wide significance was determined by a Bonferroni correction for multiple testing. Using linear regression, loci on chromosomes 2, 3, 16, 23 and 24 were significantly associated at the genome level with FEC estimated breeding values, and we identified a region on chromosome 2 that was significant using both statistical analyses. We suggest a potential role for the gene DIS3L2 for gastrointestinal nematode resistance in Katahdin sheep, although further research is needed to validate these findings.


Asunto(s)
Resistencia a la Enfermedad/genética , Enfermedades Gastrointestinales/veterinaria , Sitios Genéticos , Estudio de Asociación del Genoma Completo/veterinaria , Hemoncosis/veterinaria , Enfermedades de las Ovejas/genética , Animales , Enfermedades Gastrointestinales/genética , Enfermedades Gastrointestinales/parasitología , Hemoncosis/genética , Hemoncosis/parasitología , Ovinos , Enfermedades de las Ovejas/parasitología
4.
J Anim Sci ; 96(5): 1590-1599, 2018 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-29635633

RESUMEN

Reliance on anthelmintic drugs to control internal parasites in sheep is no longer sustainable because of the development of resistance to these drugs in parasite populations. Genetic selection may offer an alternative long-term solution, as differences in parasite resistance exist both within and among sheep breeds. However, selection for parasite resistance may have correlated effects on other production traits. The objectives of this study were to estimate genetic parameters for weaning (WFEC) and postweaning (PWFEC) fecal egg counts (FEC) and assess their relationship with birth (BWT), weaning (WWT), and postweaning (PWWT) BW in Katahdin lambs. The study used WFEC (n = 2,537), PWFEC (n = 3.421), BWT (n = 12,869), WWT (n = 10,961), and PWWT (n = 7,812) from 12,869 lambs measured between 2003 and 2015 in 13 flocks enrolled in the U.S. National Sheep Improvement Program. Animal and sire models were fitted to the data using the ASReml statistical package. Records were corrected for fixed effects of dam age, joint effect of type of birth and rearing, and management group (defined by joint effects of flock, sex, and birth year and season); lamb age in days at each measurement time was fitted as a covariate. Maternal additive and maternal permanent environmental effects were not significant (P > 0.05), but litter effects influenced (P < 0.01) both WFEC and PWFEC. Heritability estimates ranged from 0.18 to 0.26 for WFEC and 0.23 to 0.46 for PWFEC, depending on the model used. Heritability estimates from sire models were higher than estimates from animal models. Direct additive, litter, residual, and phenotypic correlations between WFEC and PWFEC were 0.82, 0.25, 0.15, and 0.29, respectively. Bivariate analyses revealed low to moderate correlations between BW and FEC. Moderate heritabilities for FEC in this study indicated that genetic progress for this trait can be achieved in Katahdin lambs and that selection for low FEC should have little or no effect on BW.


Asunto(s)
Antihelmínticos/uso terapéutico , Heces/parasitología , Helmintiasis Animal/parasitología , Helmintos/aislamiento & purificación , Recuento de Huevos de Parásitos/veterinaria , Enfermedades de las Ovejas/parasitología , Animales , Peso Corporal/genética , Cruzamiento , Clima , Femenino , Masculino , Fenotipo , Estaciones del Año , Ovinos , Destete
5.
J Anim Sci ; 95(3): 1118-1123, 2017 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-28380511

RESUMEN

The FAMACHA system was introduced to the U.S. just over 10 yr ago to allow selective deworming of lambs with anemia associated with and retard the development of anthelmintic resistance. The FAMACHA system was initially developed as a predictor of packed cell volume (PCV), but correlations between FAMACHA and fecal egg counts (FEC) have also been reported. It is important to understand factors that influence FAMACHA scores among farms to improve management of gastrointestinal nematodes. The objectives of this study were therefore to quantify associations between FAMACHA scores, FEC, BW, and age in Katahdin lambs at 2 different measurement times in 8 flocks in the eastern U.S., and to assess consistency of relationships between FAMACHA and FEC among flocks. Data came from 1,644 Katahdin lambs from 7 flocks sampled at approximately 90 d of age, and 1,295 lambs from 6 flocks sampled at approximately 120 d of age over a 5 yr period. Residual correlations among log-transformed FEC (LFEC), FAMACHA scores, BW, and lamb ages at each measurement time were determined. Repeatability of each variable was also determined as residual correlations among repeated measures. At both 90 and 120 d of age, correlations of FAMACHA scores with LFEC and BW were significant ( < 0.001), but numerically modest (0.25 and -0.16, respectively at 90 d; 0.31 and -0.16, respectively at 120 d), demonstrating that higher FAMACHA scores were associated with higher FEC and more likely to be observed in lighter lambs. A small negative correlation was observed between FAMACHA score and lamb age ( = -0.05, = 0.05, 90 d; = -0.11, < 0.001, 120 d) indicating that younger lambs were more likely to have elevated FAMACHA scores. Thus, younger and lighter lambs will likely be more susceptible to parasitism and may need to be managed more diligently than older or heavier lambs. In addition, FAMACHA scores have potential to improve breeding value estimates in programs designed to genetically improve parasite resistance.


Asunto(s)
Heces/parasitología , Hemoncosis/veterinaria , Recuento de Huevos de Parásitos/veterinaria , Enfermedades de las Ovejas/parasitología , Envejecimiento , Animales , Antihelmínticos/administración & dosificación , Peso Corporal , Femenino , Hemoncosis/epidemiología , Hemoncosis/parasitología , Haemonchus , Hematócrito/veterinaria , Ovinos , Estados Unidos/epidemiología
6.
J Anim Sci ; 95(1): 103-112, 2017 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28177372

RESUMEN

Selection for low fecal egg counts (FEC) can be used to genetically enhance resistance to gastrointestinal nematode parasites in growing lambs, thereby reducing the frequency of use of anthelmintics, facilitating marketing of organic lamb, and reducing the risk of development of anthelmintic resistance by the parasite. Recording of FEC in lambs has, therefore, been incorporated into several national sheep genetic evaluation programs. Ewes in late gestation and early lactation are also vulnerable to parasite infection and commonly experience a periparturient rise in FEC. This study was designed to assess factors associated with the periparturient rise in FEC in Katahdin ewes and associated changes in FEC in their lambs. Data came from 1,487 lambings by 931 Katahdin ewes from 11 farms in the Eastern United States. Fecal egg counts were measured in ewes at approximately 0, 30, and 60 d postpartum and in their lambs at approximately 60, 90, and 120 d of age. Approximately 1,400 lambs were evaluated at each measurement age. Data were analyzed separately for ewes and lambs and also initially analyzed separately for each measurement time. Repeated-measures analyses were then used to evaluate responses across measurement times. In ewes, FEC peaked at approximately 28 d postpartum, and we concluded that informative periparturient FEC could be obtained from 1 wk before until approximately 5 wk after lambing. Yearling ewes had higher FEC than adult ewes ( < 0.01), and ewes that nursed twin or triplet lambs had higher FEC than ewes that nursed single lambs ( < 0.01). In lambs, FEC increased through approximately 120 d of age. Lambs from yearling ewes and lambs nursed in larger litters were, like their dams, at greater risk of parasitism ( < 0.05). Ewes and lambs in these groups would benefit from enhanced monitoring of parasite loads at lambing and in early lactation. Correlations () between FEC in lambs at 90 d of age and FEC in ewes at 0, 30, and 60 d postpartum of 0.05 to 0.09 ( ≤ 0.05) support the presence of a genetic relationship between these 2 indicators of parasite resistance.


Asunto(s)
Antihelmínticos/uso terapéutico , Heces/parasitología , Infecciones por Nematodos/veterinaria , Recuento de Huevos de Parásitos/veterinaria , Enfermedades de las Ovejas/parasitología , Envejecimiento , Animales , Femenino , Parasitosis Intestinales/genética , Lactancia , Tamaño de la Camada , Nematodos/fisiología , Infecciones por Nematodos/parasitología , Embarazo , Ovinos , Enfermedades de las Ovejas/tratamiento farmacológico
7.
Trop Biomed ; 34(4): 770-780, 2017 Dec 01.
Artículo en Inglés | MEDLINE | ID: mdl-33592946

RESUMEN

Intestinal parasitic infections (IPIs) are a major cause of morbidity worldwide and have been described as an important public health concern. The present study aimed to determine the prevalence and identification of risk factors associated with IPIs among 3-15 years old school age children residing in Mandi Bahauddin, Pakistan from 2011- 2013. A cross sectional school-based study was conducted using a structured pre-tested questionnaire. Anthropometric tools and stool tests were used to obtain epidemiological and disease data. The direct wet mount preperation in saline/iodine/haematoxylin stain and Kato-Katz methods were used for stool examination. Data were analysed using appropriate descriptive, univariate and multivariable logistic regression methods. Of the 1,434 children studied (mean age of 8.6±3.6 years) the overall prevalence rate for intestinal parasitic infections was found to be 33.3%. Children infected with single parasite accounted for 27.6% and 5.7% were detected with poly-parasitism. The study showed that helminths (21.4%) were more prevalent than protozoans (17.9%). Ascaris lumbricoides (17.5%), Giardia lamblia (9.8%), Entamoeba histolytica (8.2%), Hymenolepis nana (2.0%), Trichuris trichiura (1.3%) and Taenia saginata (0.7%) were identified in children living in irrigated areas. The multiple logistic regression model indicated that age of the child, gender, family size, source of drinking water, type of milk used, house condition, feeding habit, personal hygiene and socioeconomic status were significantly (p<0.05) associated with the IPIs. Intestinal parasites were prevalent in varying magnitude among the schoolchildren located in irrigated areas. We conclude that there is a need for mass scale campaigns to create awareness regarding health and hygiene in children, and the need for development of effective poverty control programmes because deworming alone is not adequate to control parasitic infections.

8.
J Helminthol ; 91(5): 583-588, 2017 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-27762173

RESUMEN

Haemonchus contortus is a major parasite of small ruminants and its blood-feeding behaviour causes effects ranging from mild anaemia to death. Knowledge of the genetic variation within and among H. contortus populations can provide the foundation for understanding transmission patterns and aid in the control of haemonchosis. Adult male H. contortus were collected from three geographical regions in Egypt. The second internal transcribed spacer (ITS2) of nuclear ribosomal DNA was amplified using the polymerase chain reaction (PCR) and sequenced directly. The population genetic diversity and sequence variations were determined. Nucleotide sequence analyses revealed one genotype (ITS2) in all worms, without genetic differentiation. The similarity in population genetic diversity and genetic patterns observed among the three geographical regions could be attributed to possible movement between the sites. This is the first study of genetic variation in H. contortus in Egypt. The present results could have implications for the rapid characterization of H. contortus and other trichostrongyloid nematodes, and evaluation of the epidemiology of H. contortus in Egypt.


Asunto(s)
Variación Genética , Filogenia , Enfermedades de las Ovejas/parasitología , Trichostrongyloidea/clasificación , Trichostrongyloidea/genética , Tricostrongiloidiasis/veterinaria , Animales , Análisis por Conglomerados , ADN de Helmintos/química , ADN de Helmintos/genética , ADN Espaciador Ribosómico/química , ADN Espaciador Ribosómico/genética , Egipto , Genotipo , Masculino , Reacción en Cadena de la Polimerasa , Análisis de Secuencia de ADN , Ovinos , Trichostrongyloidea/aislamiento & purificación , Tricostrongiloidiasis/parasitología
9.
J Anim Sci ; 94(4): 1592-9, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-27136018

RESUMEN

Prolonged feeding of sericea lespedeza (SL) previously led to reduced serum concentrations of Mo, a cofactor in an enzyme complex that may be involved in weight gain. The current objective was to determine the effect of Mo supplementation on changes in serum, fecal, urine, and liver concentrations of trace minerals in lambs fed SL leaf meal pellets. Thirty ram lambs weaned in May (84 ± 1.5 d of age and 27 ± 1.1 kg; D 0) were blocked by BW, breed type (full or three-fourths Katahdin), and EBV of parasite resistance and randomly assigned to be fed 900 g/d of an alfalfa-based supplement (CON; = 10) or a SL-based supplement ( = 20) for 103 d. Supplements were formulated to be isonitrogenous and isocaloric and to meet trace mineral requirements. Within the SL group, individual lambs were administered either 5 mL water or 5 mL of water with 163.3 mg of sodium molybdate (SLMO). Serum was collected on d 28, 56, and 104; a liver sample was collected by biopsy on d 104 to determine concentrations of trace minerals. Data were analyzed using a mixed model and orthogonal contrasts. Serum concentrations of Mo increased in response to the drench and were greatest in SLMO lambs and then CON lambs and lowest in SL lambs ( < 0.001). Concentrations of Mo in the liver ( < 0.001) were similar between CON and SLMO lambs and were lower in SL lambs than other groups. Serum ( < 0.001) and liver ( = 0.013) concentrations of zinc (Zn) were reduced in both SL and SLMO lambs compared with CON lambs. Serum concentrations of cobalt (Co) increased in CON lambs compared with SL and SLMO lambs between d 0 and 56 but were similar on d 104 (diet × day, < 0.005) as with concentrations in the liver. Serum and liver concentrations of copper (Cu) were greatest ( < 0.001 and < 0.001, respectively) in CON lambs followed by SL lambs and then SLMO lambs. Serum concentrations of selenium (Se) tended ( = 0.10) to be reduced in SL lambs compared with CON and SLMO lambs, but concentrations in the liver were reduced in SL lambs compared with CON lambs and even more so in SLMO lambs ( < 0.003). Although the dietary Mo did increase stores of Mo in the animal and reduced copper, trace minerals associated with metalloproteins-Mo, copper, selenium, and zinc-were reduced in the liver of SL- and/or SLMO-fed lambs. These reductions could be associated with the lower weight gains previously observed after prolonged feeding of SL.


Asunto(s)
Alimentación Animal/análisis , Lespedeza , Molibdeno/farmacología , Ovinos , Oligoelementos/sangre , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Cobre , Dieta/veterinaria , Suplementos Dietéticos , Heces/parasitología , Masculino , Molibdeno/administración & dosificación , Selenio , Sodio en la Dieta , Oligoelementos/química , Oligoelementos/orina , Zinc
10.
Vet Parasitol ; 215: 1-4, 2016 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-26790729

RESUMEN

Control of gastrointestinal nematodes (GIN) remains a critical issue due to the prevalence of anthelmintic resistance. The objective of the experiment was to determine the efficacy of copper oxide wire particles (COWP) from three commercial sources and a combination of COWP and albendazole to control GIN and/or Haemonchus contortus in lambs. Naturally infected Katahdin lambs in early June 2014 and 2015 were randomly assigned to receive no COWP (CON; n=9 and 12) or 2g COWP in a gel capsule as Copasure(®) (COP; n=4 and 17; Animax Ltd.), copper oxide-wire form (AUS; n=7 in 2014 only; Pharmplex), Ultracruz™ (ULT; n=8 and 15; Santa Cruz Animal Health™), no COWP and albendazole (CON+alb; n=10 in 2015 only; 15mg/kg BW; Valbazen(®); Zoetis Animal Health), or COWP+alb (n=7 and 11; in 2014, lambs were administered alb on day 3). Lambs grazed grass pastures as a group and were supplemented with 227g/lamb daily of a commercial grain mix (15% crude protein) and the same amount of alfalfa pellets. Feces were collected on days 0 (day of COWP treatment), 7, and 14 for determination of fecal egg counts (FEC). Pooled (2014) or pooled treatment group feces were cultured on days 0, 7, and 14 (2015 only) to determine GIN genera. Data were analyzed using repeated measures in a mixed model, and FEC were log transformed. The predominant GIN on day 0 was H. contortus (87%) in 2014, and there was a mixed population in 2015. The mean FEC was reduced by day 7 in AUS and ULT lambs (treatment×day, P=0.001), and all of the COWP products were similar. By day 14, the AUS FEC were lower than the CON and COP groups. When examining the combination of COWP and synthetic anthelmintic, the FEC of COWP+alb were reduced to nearly 0eggs/g (back-transformed) and lower than the other groups (treatment×day, P=0.001). The percentage of H. contortus in cultured feces was reduced to a greater extent in the COWP than CON or CON+alb groups of lambs. In a mixed GIN population, the COWP products appeared to be similar in efficacy and using a combination of COWP+alb increased the efficacy not only against H. contortus, but all GIN genera present, offering options in the face of resistance to benzimidazoles.


Asunto(s)
Albendazol/uso terapéutico , Antihelmínticos/uso terapéutico , Cobre/uso terapéutico , Infecciones por Nematodos/veterinaria , Enfermedades de las Ovejas/parasitología , Albendazol/administración & dosificación , Animales , Antihelmínticos/administración & dosificación , Cobre/administración & dosificación , Quimioterapia Combinada , Heces/parasitología , Infecciones por Nematodos/prevención & control , Recuento de Huevos de Parásitos/veterinaria , Ovinos , Enfermedades de las Ovejas/prevención & control
11.
Trop Biomed ; 32(2): 257-68, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-26691254

RESUMEN

Artemisia plant genus, natural inhabitant of northern Punjab Pakistan, is well known for its anthelmintic properties; many Artemisia species have not been so far scientifically proved. The aim of this study was to assess in vitro anthelmintic activity of Artemisia indica and Artemisia roxburghiana against mixed infection of gastrointestinal nematodes in small ruminants. This study is first scientifically proven study on anthelmintic activity of A. indica and A. roxburghiana. Five different concentrations (50, 25, 12.5, 6.25 and 3.75 mg/mL) accompanied by negative control (PBS) and positive control (albendazole, 10%) were used to carry out the egg hatch inhibition assay, larval mortality assay and adult worm mortality assay. The Baermann technique was used first time in larval mortality assay and proved to be effective. The results revealed that methanolic extracts of both A. indica and A. roxburghiana, showed maximum anthelmintic activity at concentration of 50 mg/ml by egg hatch inhibition (85±21.2; 80±28.3), larvae mortality (18±2.8; 17±4.2) and adult worm mortality (8.5±2.1; 8±2.8) assays. However, at concentration of 50 mg/ml both plant extracts in comparison to albendazole showed statistically insignificant (p≤0.05) results. The A. indica showed higher anthelmintic activity at all concentrations as compared to A. roburghiana. It has been concluded both plants exhibit anthelmintic activity and further evaluation of these plants should be carried out to purify the active ingredients for anthelmintic activity. Moreover, the decoctions of these plants could be used to GINs after confirming anthelmintic properties through in vivo.


Asunto(s)
Antihelmínticos/farmacología , Artemisia/química , Nematodos/efectos de los fármacos , Extractos Vegetales/farmacología , Animales , Antihelmínticos/aislamiento & purificación , Bioensayo , Pakistán , Pruebas de Sensibilidad Parasitaria , Extractos Vegetales/aislamiento & purificación , Análisis de Supervivencia
12.
J Anim Sci ; 93(4): 1952-61, 2015 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26020218

RESUMEN

Sericea lespedeza (SL; Lespedeza cuneata) is a legume rich in condensed tannins that can be grazed or fed to small ruminants for parasite control. Condensed tannins, a secondary plant compound in SL, may lead to unintended consequences such as changes in production. In our preliminary research, there was consistently a reduction in serum and liver concentrations of Mo. The objective of this study was to determine the effect of SL with or without Mo supplementation on changes in BW, hematology, and serum biochemistry in lambs. Thirty ram lambs weaned in May (84 ± 1.5 d of age; 27 ± 1.1 kg) were blocked by BW, breed type (full or three-fourths Katahdin), and EBV of parasite resistance and randomly assigned to be fed 900 g of alfalfa-based supplement (CON; n = 10) or SL-based supplement (n = 20) for 103 d. Supplements were formulated to be isonitrogenous and isocaloric and to meet trace mineral requirements. Within the SL diet, half of the lambs received 490 mg sodium molybdate weekly (SLMO). Body condition scores and BW were determined every 14 d and blood and feces collected to determine hematological and serum biochemical profiles and fecal egg counts (FEC). Data were analyzed using a mixed model with repeated measures and orthogonal contrasts. The white blood cell counts tended to be reduced in SL- and SLMO-fed lambs compared with CON-fed lambs (P < 0.06), which was associated with a reduction in neutrophils (P < 0.001). Red blood cell counts were also reduced in SL but not SLMO lambs compared with CON lambs (P < 0.04). There was a reduction in blood packed cell volume (P < 0.04) and serum concentrations of albumin (P < 0.001) and creatinine (P < 0.02) in both SL and SLMO lambs compared with CON lambs. Similarly, concentrations of blood urea nitrogen were reduced in both SL and SLMO lambs, but differences among dietary treatments disappeared after 42 d of feeding (treatment × day, P < 0.004). Serum concentrations of total proteins were reduced only in SLMO lambs compared with other lambs (P < 0.001). Body weight and FEC were similar among dietary treatments. Means of all measurements were within a normal range, even though there were subtle but significant differences between dietary groups. Feeding a diet high in condensed tannin-rich SL did not lead to serious effects on hematology or serum biochemistry in lambs.


Asunto(s)
Enfermedades Gastrointestinales/veterinaria , Lespedeza , Molibdeno/uso terapéutico , Infecciones por Nematodos/veterinaria , Enfermedades de las Ovejas/prevención & control , Oveja Doméstica/sangre , Oveja Doméstica/parasitología , Taninos/uso terapéutico , Alimentación Animal , Animales , Células Sanguíneas/efectos de los fármacos , Peso Corporal/efectos de los fármacos , Dieta/veterinaria , Suplementos Dietéticos , Heces/parasitología , Enfermedades Gastrointestinales/parasitología , Enfermedades Gastrointestinales/prevención & control , Masculino , Molibdeno/administración & dosificación , Molibdeno/farmacología , Nematodos/aislamiento & purificación , Infecciones por Nematodos/prevención & control , Recuento de Huevos de Parásitos/veterinaria , Ovinos , Enfermedades de las Ovejas/parasitología , Taninos/administración & dosificación , Taninos/farmacología , Resultado del Tratamiento
13.
Vet Parasitol ; 207(1-2): 170-5, 2015 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-25465738

RESUMEN

Sericea lespedeza (SL; Lespedeza cuneata) is a perennial warm-season forage rich in condensed tannins (CT) that has been reported to have anthelmintic activity against small ruminant gastrointestinal nematodes (GIN), particularly Haemonchus contortus, a highly pathogenic blood-feeder, but the mechanism of action of CT against H. contortus is not clearly understood. An experiment with young goats was designed to study the effect of SL leaf meal pellets on (1) a mature H. contortus infection, and (2) the surface appearance of adult H. contortus female worms. Thirty-six female and castrated male Boer crossbred goats artificially infected with H. contortus larvae were fed 75% SL leaf meal pellets or alfalfa pellets (18 goats/treatment group) in a 28-day confinement feeding trial. Fecal and blood samples were collected weekly for fecal egg count (FEC) and packed cell volume (PCV) determination, respectively, and all goats were slaughtered at the end of the trial for adult GIN recovery and counting. Five adult female H. contortus were recovered from the abomasum of two goats from each treatment group and from a prior study in which 75% and 95% SL leaf meal pellets or a commercial feed pellet were group-fed to grazing goats (270 days old, Spanish males, 10/treatment group) at 0.91 kg/head/d for 11 weeks. Adult GIN collected were fixed and examined for evidence of surface damage using scanning electron microscopy. Feeding 75% SL pellets to young goats in confinement reduced (P<0.05) FEC compared with control animals, while total worm numbers and PCV were not influenced by treatment. Three out of the 5 adult H. contortus recovered from SL treatment goats in the confinement feeding trial had cuticular surface damage, while no damage was observed on worms from the control group. All five worms observed from both SL treatments in the grazing study showed a shrunken, disheveled cuticular surface, whereas this was not observed on worms from control animals. Overall, this work suggests that a possible mechanism of action of SL against female H. contortus in the animal's abomasum is a direct action of CT on the cuticle of the worm.


Asunto(s)
Enfermedades de las Cabras/tratamiento farmacológico , Hemoncosis/veterinaria , Haemonchus/efectos de los fármacos , Lespedeza/química , Proantocianidinas/farmacología , Alimentación Animal/análisis , Animales , Antihelmínticos/uso terapéutico , Heces/parasitología , Femenino , Enfermedades de las Cabras/parasitología , Cabras , Hemoncosis/tratamiento farmacológico , Hemoncosis/parasitología , Haemonchus/ultraestructura , Masculino , Microscopía Electrónica de Rastreo/veterinaria , Recuento de Huevos de Parásitos/veterinaria , Hojas de la Planta/química
14.
Vet Parasitol ; 204(3-4): 221-8, 2014 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-24996964

RESUMEN

High prevalence of anthelmintic-resistant gastrointestinal nematodes (GIN) in goats has increased pressure to find effective, alternative non-synthetic control methods, one of which is adding forage of the high condensed tannin (CT) legume sericea lespedeza (SL; Lespedeza cuneata) to the animal's diet. Previous work has demonstrated good efficacy of dried SL (hay, pellets) against small ruminant GIN, but information is lacking on consumption of fresh SL, particularly during the late summer-autumn period in the southern USA when perennial warm-season grass pastures are often low in quality. A study was designed to determine the effects of autumn (September-November) consumption of fresh SL forage, grass pasture (predominantly bermudagrass, BG; Cynodon dactylon), or a combination of SL+BG forage by young goats [intact male Spanish kids, 9 months old (20.7 ± 1.1 kg), n = 10/treatment group] on their GIN infection status. Three forage paddocks (0.40 ha) were set up at the Fort Valley State University Agricultural Research Station (Fort Valley, GA) for an 8-week trial. The goats in each paddock were supplemented with a commercial feed pellet at 0.45 kg/head/d for the first 4 weeks of the trial, and 0.27 kg/head/d for the final 4 weeks. Forage samples taken at the start of the trial were analyzed for crude protein (CP), neutral detergent fiber (NDF), and acid detergent fiber (ADF) content, and a separate set of SL samples was analyzed for CT in leaves, stems, and whole plant using the benzyl mercaptan thiolysis method. Animal weights were taken at the start and end of the trial, and fecal and blood samples were collected weekly for determination of fecal egg counts (FEC) and packed cell volume (PCV), respectively. Adult GIN was recovered from the abomasum and small intestines of all goats at the end of the experiment for counting and speciation. The CP levels were highest for SL forage, intermediate for SL+BG, and lowest for BG forage samples, while NDF and ADF values were the opposite, with highest levels in BG and lowest in SL forage samples. Sericea lespedeza leaves had more CT than stems (16.0 g vs. 3.3g/100g dry weight), a slightly higher percentage of PDs (98% vs. 94%, respectively) and polymers of larger mean degrees of polymerization (42 vs. 18, respectively). There were no differences in average daily gain or blood PCV between the treatment groups, but SL goats had lower FEC (P < 0.05) than the BG or SL+BG forage goats throughout most of the trial. The SL+BG goats had lower FEC than the BG forage animals by the end of the trial (week 8, P < 0.05). The SL goats had lower numbers (P < 0.05) of male Haemonchus contortus and tended to have fewer female (P < 0.10) and total (P < 0.07) H. contortus compared with the BG goats. The predominant GIN in all the goats was Trichostrongylus colubriformis (73% of total GIN). As a low-input forage with activity against pathogenic GIN (H. contortus), SL has a potential to reduce producers' dependence upon synthetic anthelmintics and also to fill the autumn 'window' in good-quality fresh forages for goat grazing in the southern USA.


Asunto(s)
Antihelmínticos/farmacología , Enfermedades de las Cabras/prevención & control , Hemoncosis/veterinaria , Lespedeza , Nematodos/efectos de los fármacos , Infecciones por Nematodos/veterinaria , Abomaso , Alimentación Animal/análisis , Animales , Peso Corporal , Dieta/veterinaria , Heces/parasitología , Femenino , Enfermedades Gastrointestinales/prevención & control , Enfermedades Gastrointestinales/veterinaria , Cabras , Hemoncosis/prevención & control , Haemonchus/efectos de los fármacos , Masculino , Infecciones por Nematodos/prevención & control , Recuento de Huevos de Parásitos/veterinaria , Proantocianidinas/farmacología
15.
Vet Parasitol ; 204(3-4): 191-8, 2014 Aug 29.
Artículo en Inglés | MEDLINE | ID: mdl-24857771

RESUMEN

Infection with Eimeria spp. (coccidia) can be devastating in goats, particularly for young, recently-weaned kids, resulting in diarrhea, dehydration, and even death. Feeding dried sericea lespedeza [SL; Lespedeza cuneata (Dum.-Cours.) G. Don.] to young goats has been reported to reduce the effects of internal parasites, including gastrointestinal nematodes (GIN) but there have been no reports of the effects of feeding this forage on Eimeria spp. in goats. Two confinement feeding experiments were completed on recently-weaned intact bucks (24 Kiko-cross, Exp. 1; 20 Spanish, Exp. 2) to determine effects of SL pellets on an established infection of GIN and coccidia. The bucks were assigned to 1 of 2 (Exp. 1) or 3 (Exp. 2) treatment groups based upon the number of Eimeria spp. oocysts per gram (OPG) of feces. In Exp. 1, the kids were fed 1 of 2 pelleted rations ad libitum; 90% SL leaf meal+10% of a liquid molasses/lignin binder mix and a commercial pellet with 12% crude protein (CP) and 24% acid detergent fiber (n=12/treatment group, 2 animals/pen). For Exp. 2, treatment groups were fed (1) 90% SL leaf meal pellets from leaves stored 3 years (n=7), (2) 90% SL pellets from leaf meal stored less than 6 months, (n=7), and the commercial pellets (n=6) ad libitum. For both trials, fecal and blood samples were taken from individual animals every 7 days for 28 days to determine OPG and GIN eggs per gram (EPG) and packed cell volume (PCV), respectively. In Exp. 2, feces were scored for consistency (1=solid pellets, 5=slurry) as an indicator of coccidiosis. In Exp. 1, EPG (P<0.001) and OPG (P<0.01) were reduced by 78.7% and 96.9%, respectively, 7 days after initiation of feeding in goats on the SL pellet diet compared with animals fed the control pellets. The OPG and EPG remained lower in treatment than control animals until the end of the trial. In Exp. 2, goats fed new and old SL leaf meal pellets had 66.2% and 79.2% lower (P<0.05) EPG and 92.2% and 91.2% lower (P<0.05) OPG, respectively, than control animals within 7 days, and these differences were maintained or increased throughout the trial. After 4 weeks of pellet feeding in Exp. 2, fecal scores were lower (P<0.01) in both SL-fed groups compared with control animals, indicating fewer signs of coccidiosis. There was no effect of diet on PCV values throughout either experiment. Dried, pelleted SL has excellent potential as a natural anti-coccidial feed for weaned goats.


Asunto(s)
Coccidiosis/veterinaria , Eimeria/efectos de los fármacos , Enfermedades de las Cabras/prevención & control , Lespedeza , Nematodos/efectos de los fármacos , Infecciones por Nematodos/veterinaria , Alimentación Animal/análisis , Animales , Coccidiosis/prevención & control , Diarrea/veterinaria , Dieta/veterinaria , Heces/parasitología , Tracto Gastrointestinal/parasitología , Cabras , Masculino , Infecciones por Nematodos/prevención & control , Recuento de Huevos de Parásitos/veterinaria , Hojas de la Planta , Destete
16.
Phys Chem Chem Phys ; 16(18): 8418-27, 2014 May 14.
Artículo en Inglés | MEDLINE | ID: mdl-24668070

RESUMEN

Widespread adoption of solar-thermochemical fuel production depends on its economic viability, largely driven by the efficiency of use of the available solar resource. Herein, we analyze the efficiency of two-step cycles for thermochemical hydrogen production, with emphasis on efficiency. Owing to water thermodynamics, isothermal H2 production is shown to be impractical and inefficient, irrespective of reactor design or reactive oxide properties, but an optimal temperature difference between cycle steps, for which efficiency is the highest, can be determined for a wide range of other operating parameters. A combination of well-targeted pressure and temperature swing, rather than either individually, emerges as the most efficient mode of operation of a two-step thermochemical cycle for solar fuel production.

17.
Vet Parasitol ; 200(3-4): 271-5, 2014 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-24439849

RESUMEN

The objective of this study was to determine the impact of integrated parasite management (IPM) training, including FAMACHA(©) eyelid color scoring, on the ability of U.S. sheep and goat producers to control gastrointestinal nematodes (GIN) on their farms. A survey was developed and provided to over 2000 producers trained from 2004 to 2008 in IPM with questions involving farm size (number of sheep/goats), location (U.S. state), impact of training on parasite control efforts and parasite problems on farm, and IPM practices used. Responses were divided into U.S. Census regions of the U.S. Descriptive statistics and logistic regression were used to describe results. Most of the 729 respondents were from the southern region of the U.S. (54.3%) and were small-scale producers (50 or less animals; 64.8%). Nearly all of the respondents (95.1%) agreed that IPM workshop attendance made a difference in their ability to control and monitor parasitism in their herd or flock and employed IPM practices to control GIN (96.3%). The most popular practices respondents used were rotational grazing (71.2%), genetic selection (choosing a parasite resistant breed and/or culling susceptible animals; 52.7%), grain supplementation on pasture to improve nutrition (44.0%), and increased height of plants being grazed (41.8%). Although reporting using a practice decreased (P<0.05) the likelihood of reporting fewer problems, for each 1-point increase in the number of practices which producers employed to control internal parasitism in their herd or flock, they were 16% more likely to report fewer GIN problems (P<0.05). Approximately 75% of respondents indicated an economic benefit of IPM on their farm (P<0.05), and those reporting savings of over $80 were more likely to report fewer problems (P<0.05) with parasites after the training while those reporting no economic benefit were less likely to report fewer problems with GIN (P<0.001). Overall, IPM training resulted in positive impacts for producers responding to the survey and should continue.


Asunto(s)
Crianza de Animales Domésticos/educación , Crianza de Animales Domésticos/estadística & datos numéricos , Educación/normas , Enfermedades Gastrointestinales/veterinaria , Enfermedades de las Cabras/prevención & control , Infecciones por Nematodos/veterinaria , Enfermedades de las Ovejas/prevención & control , Animales , Enfermedades Gastrointestinales/parasitología , Enfermedades Gastrointestinales/prevención & control , Enfermedades de las Cabras/parasitología , Cabras , Nematodos/fisiología , Infecciones por Nematodos/prevención & control , Evaluación de Programas y Proyectos de Salud , Ovinos , Enfermedades de las Ovejas/parasitología , Estados Unidos
18.
Vet Parasitol ; 197(1-2): 152-9, 2013 Oct 18.
Artículo en Inglés | MEDLINE | ID: mdl-23953143

RESUMEN

Gastrointestinal nematode (GIN) parasite control recommendations are in a state of flux because of the increase in anthelmintic resistant cattle parasites, such as Cooperia spp. In addition, Cooperia spp. infection is typically high in warm-season grass pastures and can affect growth performance of grazing stocker calves in the Gulf Coast Region. This study evaluated the effects of moxidectin pour-on, oxfendazole oral suspension, or a combination of the two given at separate times on infection and performance of weaned beef calves grazing summer forages. Steers (n=42) and heifers (n=31) were stratified by sex, d-11 fecal egg count (FEC), and d-1 shrunk body weight (BW) to one of 10 pastures with four anthelmintic treatments and one control. Treatments included: (1) oxfendazole given on d 0 and moxidectin on d 73 (O+M), (2) moxidectin given on d 0 and oxfendazole on d 73 (M+O), (3) moxidectin given on d 0 (M), (4) oxfendazole given on d 0 (O) and (5) no anthelmintic given (CON). Calves grazed for d-110 beginning May 27th. Response variables were FEC (collected on d-11, 14, 31, 45, 59, 73, 87 and 108), coprocultures (evaluated for d 87 and 108), final shrunk BW, shrunk BW gain, average daily gain (ADG), and full BW gain (collected on d 31, 59, 73, 87, and 108). Calves treated with either oxfendazole (O+M and O) or moxidectin (M+O and M) on d 0 had significantly lower (P<0.001) FEC than the CON calves on d 14, 31 and 45. However, the M+O treated calves had significantly higher (P<0.001) FEC than both oxfendazole treated groups. In addition, calves treated with a second dewormer on d 73 (O+M and M+O) had significantly lower (P<0.001) FEC by d 87 than the CON or M treated calves. Shrunk BW gain and ADG were significantly greater (P=0.005) for the O+M compared to the M treated and CON calves, but comparable with the M+O and O treated calves, respectively. Coprocultures sampled on d 87 and 108 for calves not receiving a second dewormer were predominantly Cooperia spp. and Ostertagia spp. On d 87, no larvae were recovered from the M+O treated calves, whereas the O+M treated calves had 94% Cooperia spp. and 3% Ostertagia spp. recovered. Providing a benzimidazole with a macrocyclic lactone given at two different periods may provide better GIN parasite control and improve animal gains for stocker calves grazing warm-season grass pastures.


Asunto(s)
Antihelmínticos/uso terapéutico , Bencimidazoles/uso terapéutico , Enfermedades de los Bovinos/parasitología , Enfermedades Gastrointestinales/veterinaria , Macrólidos/uso terapéutico , Infecciones por Nematodos/veterinaria , Animales , Bencimidazoles/administración & dosificación , Peso Corporal , Bovinos , Enfermedades de los Bovinos/tratamiento farmacológico , Quimioterapia Combinada , Femenino , Enfermedades Gastrointestinales/tratamiento farmacológico , Enfermedades Gastrointestinales/parasitología , Macrólidos/administración & dosificación , Masculino , Infecciones por Nematodos/tratamiento farmacológico
19.
Vet Parasitol ; 193(1-3): 39-46, 2013 Mar 31.
Artículo en Inglés | MEDLINE | ID: mdl-23286994

RESUMEN

The objective was to examine the effects of feeding sericea lespedeza leaf meal (SL) on control of coccidiosis in lambs. In Exp. 1, naturally infected lambs (n=76) were weaned (102.7±1.4 d of age) in May (spring) and randomly assigned in a 2×2 factorial design to receive 2% of BW/d of alfalfa pellets (control) or SL with or without amprolium added to drinking water (n=38/level or 19/treatment). Fecal oocyst counts (FOC), egg counts (FEC), and fecal score (1=solid pellets; 5=slurry) were determined every 7d between weaning and 21 d post-weaning. In Exp. 2, twin rearing ewes were randomly assigned to two groups, and their naturally infected lambs were fed a control creep supplement (16% CP; n=40) or SL pellets (14% CP; n=32) 30 d before weaning. Intake of SL was initially low (100g/lamb daily) and increased to 454 g/lamb daily after weaning. Lambs were weaned at 103.6±0.9 d of age and moved to semi-confinement. The FEC, FOC, packed cell volume (PCV), fecal score, and dag score (soiling around rear of lamb; 1=no soiling; 5=heavy soiling) were determined at d -14, 0 (weaning), 7, 14, and 21. In Exp. 3, lambs were randomly assigned to a control or SL diet (n=12/diet) fed at 1.4 kg/d for 22d and inoculated with 50,000 sporulated oocysts on d 8, 11, and 13. The FEC, FOC, and fecal score were determined every 2 to 3d between d 1 and 29 (d 0=first day of dietary treatment). Data on all experiments were analyzed using mixed models. The FOC and FEC data were log transformed. Chi squared analysis was used to determine differences in incidence of treatment (sulfadimethoxine) for coccidiosis in Exp. 1 and 2. In Exp. 1, FOC and FEC were similar between dietary groups, and FOC declined more rapidly in amprolium treated lambs following weaning (P<0.001). Fecal score was higher in the control compared with the SL fed lambs (P=0.05), suggesting more signs of coccidiosis in control lambs. In Exp. 2, FOC was similar initially but was reduced in SL fed lambs by weaning and remained lower thereafter (P=0.004). Dag (P=0.01) and fecal (P=0.001) scores were similar before weaning, but lower in SL fed lambs by weaning and remained lower thereafter. No SL lambs required treatment for coccidiosis, whereas 33% of control lambs required treatment (P<0.001). Fecal egg counts were similar before weaning but were reduced in SL compared with control fed lambs after weaning (P<0.001). In Exp. 3, FOC (P<0.001) and FEC (P<0.001) were reduced in SL compared with control fed lambs. Sericea lespedeza was effective in the prevention and control of coccidiosis as well as in reducing GIN infection. Use of SL could reduce lamb loss post-weaning, reduce the need to treat for coccidiosis, and create a significant economic benefit to livestock producers.


Asunto(s)
Alimentación Animal/análisis , Coccidiosis/veterinaria , Eimeria , Lespedeza/química , Enfermedades de las Ovejas/prevención & control , Animales , Coccidiosis/parasitología , Coccidiosis/terapia , Diarrea/parasitología , Diarrea/patología , Diarrea/prevención & control , Diarrea/veterinaria , Dieta/veterinaria , Ovinos , Destete
20.
Vet Parasitol ; 191(1-2): 51-8, 2013 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-22985929

RESUMEN

Feeding sun-dried sericea lespedeza [SL; Lespedeza cuneata (Dum-Cours.) G. Don.] reduces gastrointestinal nematode (GIN) infection in goats fed in confinement, but effects of this forage when fed as a supplement to goats on pasture are unclear. A study was completed in which supplemental feeds (75 and 95% SL leaf meal pellets and a commercial pellet, all fed at 0.91 kg/head/day) were offered to thirty growing male Spanish goats (9 months old, 20.6 ± 2.8 kg, 10/treatment) grazing perennial warm-season grass pastures in Fort Valley, GA, from September to November, 2010. Fecal and blood samples were taken from individual animals weekly to determine fecal egg count (FEC) and packed cell volume (PCV), respectively, and animal weights were recorded at the start and end of the trial. After 11 weeks grazing, animals were slaughtered for recovery, counting, and speciation of adult GIN from the abomasum and small intestines. There was no difference in FEC between goats fed the 75 and 95% SL leaf meal pellets, but both groups had lower (P<0.05) FEC than the goats fed the commercial pellets from days 35 to 77. The PCV values were not affected by the dietary treatments. Animal gain per day averaged 102.0, 77.2, and 53.3g for goats fed 95% SL, commercial, and 75% SL pellets, respectively (P<0.05). The 95% SL leaf meal pellet goats had 93.0 and 47.3% fewer (P<0.05) total (male+female) adult Haemonchus contortus and Teladorsagia circumcincta, respectively, than control animals, while only male H. contortus were lower (47.6%; P<0.05) in 75% SL-fed goats compared with commercial pellet-fed animals. Feeding supplemental SL leaf meal pellets improved animal performance (95% SL pellets) and reduced worm burdens (75 and 95% SL pellets) in young grazing goats and is a useful tool for natural GIN control in small ruminants.


Asunto(s)
Suplementos Dietéticos , Enfermedades de las Cabras/terapia , Lespedeza/metabolismo , Infecciones por Nematodos/veterinaria , Hojas de la Planta , Abomaso/parasitología , Animales , Peso Corporal , Dieta/veterinaria , Heces/parasitología , Femenino , Cabras , Hematócrito , Intestino Delgado/parasitología , Masculino , Infecciones por Nematodos/terapia , Recuento de Huevos de Parásitos
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