580 research outputs found
Expression of Ifnlr1 on intestinal epithelial cells is critical to the antiviral effects of IFN-lambda against norovirus and reovirus
Lambda interferon (IFN-λ) has potent antiviral effects against multiple enteric viral pathogens, including norovirus and rotavirus, in both preventing and curing infection. Because the intestine includes a diverse array of cell types, however, the cell(s) upon which IFN-λ acts to exert its antiviral effects is unclear. Here, we sought to identify IFN-λ-responsive cells by generation of mice with lineage-specific deletion of the receptor for IFN-λ, Ifnlr1. We found that expression of IFNLR1 on intestinal epithelial cells (IECs) in the small intestine and colon is required for enteric IFN-λ antiviral activity. IEC Ifnlr1 expression also determines the efficacy of IFN-λ in resolving persistent murine norovirus (MNoV) infection and regulates fecal shedding and viral titers in tissue. Thus, the expression of Ifnlr1 by IECs is necessary for the response to both endogenous and exogenous IFN-λ. We further demonstrate that IEC Ifnlr1 expression is required for the sterilizing innate immune effects of IFN-λ by extending these findings in Rag1-deficient mice. Finally, we assessed whether our findings pertained to multiple viral pathogens by infecting mice specifically lacking IEC Ifnlr1 expression with reovirus. These mice phenocopied Ifnlr1-null animals, exhibiting increased intestinal tissue titers and enhanced reovirus fecal shedding. Thus, IECs are the critical cell type responding to IFN-λ to control multiple enteric viruses. This is the first genetic evidence that supports an essential role for IECs in IFN-λ-mediated control of enteric viral infection, and these findings provide insight into the mechanism of IFN-λ-mediated antiviral activity. IMPORTANCE Human noroviruses (HNoVs) are the leading cause of epidemic gastroenteritis worldwide. Type III interferons (IFN-λ) control enteric viral infections in the gut and have been shown to cure mouse norovirus, a small-animal model for HNoVs. Using a genetic approach with conditional knockout mice, we identified IECs as the dominant IFN-λ-responsive cells in control of enteric virus infection in vivo. Upon murine norovirus or reovirus infection, Ifnlr1 depletion in IECs largely recapitulated the phenotype seen in Ifnlr1(−/−) mice of higher intestinal tissue viral titers and increased viral shedding in the stool. Moreover, IFN-λ-mediated sterilizing immunity against murine norovirus requires the capacity of IECs to respond to IFN-λ. These findings clarify the mechanism of action of this cytokine and emphasize the therapeutic potential of IFN-λ for treating mucosal viral infections
Adolescent Females With Communication Disorders Involved in Violence: Educators\u27 Opinions
This study focused on increasing the awareness of educational leaders about the relationship between students with communication disorders and violence. A review of selected research on adolescent females with language problems residing in a correctional facility served to support a survey study and extend discussions about the need for educational leadership within this population. Ninety-six speech-language pathologists, special educators, and teachers were surveyed about their training and knowledge on the role of communication in violence. Findings suggested the majority of participants agreed on the importance of planning prevention programs. However, they did not receive training and were uncertain about providing services to students with communication disorders. Implications are provided for administrators and other school leaders to consider when planning programs
Adolescent Females With Communication Disorders Involved in Violence: Educators\u27 Opinions
This study focused on increasing the awareness of educational leaders about the relationship between students with communication disorders and violence. A review of selected research on adolescent females with language problems residing in a correctional facility served to support a survey study and extend discussions about the need for educational leadership within this population. Ninety-six speech-language pathologists, special educators, and teachers were surveyed about their training and knowledge on the role of communication in violence. Findings suggested the majority of participants agreed on the importance of planning prevention programs. However, they did not receive training and were uncertain about providing services to students with communication disorders. Implications are provided for administrators and other school leaders to consider when planning programs
Use of indirect calorimetry to evaluate utilization of energy in lactating Jersey dairy cattle consuming common coproducts
The use of coproducts as an alternative feed source is a common practice when formulating dairy rations. A study using 12 multiparous (79 ± 16 d in milk; mean ± standard deviation) lactating Jersey cows was conducted over 5 mo to evaluate the effects of dried distillers grains with solubles (DDGS) or canola meal on milk and gas production. A replicated 4 × 4 Latin square design was used to compare 4 dietary treatments. Treatments comprised a control (CON) containing no coproducts, a treatment diet containing 10% (dry matter basis) lowfat DDGS (LFDG), a treatment diet containing 10% high-fat DDGS (HFDG), and a 10% canola meal (CM) treatment. The crude fat content of the LFDG, HFDG, and CM treatments was 6.05 ± 0.379, 10.0 ± 0.134, and 3.46 ± 0.085%, respectively. Coproducts were included in partial replacement for corn and soybean meal. Indirect headbox-style calorimeters were used to estimate heat production. Dry matter intake and milk yield were similar between all treatments, averaging 17.4 ± 0.56 kg/d and 24.0 ± 0.80 kg, respectively. Milk urea N was affected by treatment and was highest in CON (20.6 mg/dL; 18.0, 19.9, and 18.1 ± 0.62 mg/dL in LFDG, CM, and HFDG, respectively). Heat production per unit of metabolic body weight tended to be affected by treatment and was lowest for CON, and diets containing coproducts were not different (192, 200, 215, and 204 ± 5.91 kcal/kg of metabolic body weight for CON, LFDG, CM, and HFDG, respectively). The concentration of metabolizable energy was affected by dietary treatment; specifically, HFDG did not differ from CON but was greater than LFDG and CM (2.58, 2.46, 2.29, and 2.27 ± 0.09 Mcal/kg for HFDG, CON, LFDG, and CM, respectively). The concentration of net energy balance (milk plus tissue) tended to be affected by dietary treatment; HFDG did not differ from either CON or LFDG, but it was higher than CM (1.38, 1.36, 1.14, and 1.06 ± 0.11 Mcal/kg for HFDG, CON, LFDG, and CM, respectively). Results of this study indicate that milk production and dry matter intake were not affected by feeding common coproducts and that differences may result in whole-animal energy use; fat content of DDGS is a major factor affecting this
Increasing the concentration of linolenic acid in diets fed to Jersey cows in late lactation does not affect methane production
Although the inclusion of fat has reduced methane production in ruminants, relatively little research has been conducted comparing the effects of source and profile of fatty acids on methane production in lactating dairy cows. A study using 8 multiparous (325 ± 17 DIM; mean ± SD) lactating Jersey cows was conducted to determine effects of feeding canola meal and lard versus extruded byproduct containing flaxseed as a high-C18:3 fat source on methane production and diet digestibility in late-lactation dairy cows. A crossover design with 32-d periods (28-d adaptation and 4-d collections) was used to compare 2 different fat sources. Diets contained approximately 50% forage mixture of corn silage, alfalfa hay, and brome hay; the concentrate mixture changed between diets to include either (1) a conventional diet of corn, soybean meal, and canola meal with lard (control) or (2) a conventional diet of corn and soybean meal with an extruded byproduct containing flaxseed (EXF) as the fat source. Diets were balanced to decrease corn, lard, and canola meal and replace them with soybean mean and EXF to increase the concentration of C18:3 (0.14 vs. 1.20% of DM). Methane production was measured using headbox-style indirect calorimeters. Cattle were restricted to 95% ad libitum feed intake during collections. Milk production (17.4 ± 1.04 kg/d) and dry matter intake (15.4 ± 0.71 kg/d) were similar among treatments. Milk fat (5.88 ± 0.25%) and protein (4.08 ± 0.14%) were not affected by treatment. For methane production, no difference was observed for total production (352.0 vs. 349.8 ± 16.43 L/d for control vs. EXF, respectively). Methane production per unit of dry matter intake was not affected and averaged 23.1 ± 0.57 L/kg. Similarly, methane production per unit of energy-corrected milk was not affected by fat source and averaged 15.5 ± 0.68 L/kg. Heat production was similar, averaging 21.1 ± 1.02 Mcal/d. Digestibility of organic matter, neutral detergent fiber, and crude protein was not affected by diet and averaged 69.9, 53.6, and 73.3%, respectively. Results indicated that increasing C18:3 may not affect methane production or digestibility of the diet in lactating dairy cows
Long-distance migrants vary migratory behaviour as much as short-distance migrants : an individual-level comparison from a seabird species with diverse migration strategies
As environmental conditions fluctuate across years, seasonal migrants must determine where and when to move without comprehensive knowledge of conditions beyond their current location. Animals can address this challenge by following cues in their local environment to vary behaviour in response to current conditions, or by moving based on learned or inherited experience of past conditions resulting in fixed behaviour across years. It is often claimed that long-distance migrants are more fixed in their migratory behaviour because as distance between breeding and wintering areas increases, reliability of cues to predict distant and future conditions decreases. While supported by some population-level studies, the influence of migration distance on behavioural variation is seldom examined on an individual level. Lesser black-backed gulls Larus fuscus are generalist seabirds that use a diversity of migration strategies. Using high-resolution multi-year GPS tracking data from 82 individuals from eight colonies in Western Europe, we quantified inter- and intra-individual variation in non-breeding distributions, winter site fidelity, migration routes and timing of migration, with the objectives of determining how much variation lesser black-backed gulls have in their migratory behaviour and examining whether variation changes with migration distance. We found that intra-individual variation was significantly lower than variation between individuals for non-breeding distributions, winter site fidelity, migration routes and timing of migration, resulting in consistent individual strategies for all behaviours examined. Yet, intra-individual variation ranged widely among individuals (e.g. winter site overlap: 0-0.91 out of 1; migration timing: 0-192 days), and importantly, individual differences in variation were not related to migration distance. The apparent preference for maintaining a consistent strategy, present in even the shortest distance migrants, suggests that familiarity may be more advantageous than exactly tracking current environmental conditions. Yet, variation in behaviour across years was observed in many individuals and could be substantial. This suggests that individuals, irrespective of migration distance, have the capacity to adjust to current conditions within the broad confines of their individual strategies, and occasionally, even change their strategy
Missouri agriculture : a growing industry, some comparison with the past
March 1991"Published by Missouri Agricultural Experiment Station University of Missouri-Columbia in cooperation with Office of Social and Economic Data Analysis University of Missouri System" -- verso t.p
Reducing methane production with corn oil and calcium sulfate: Responses on whole-animal energy and nitrogen balance in dairy cattle
The addition of fat and calcium sulfate to diets fed to ruminants has resulted in a reduction in methane production, but the effects on energy balance have not been studied. A study using indirect calorimetry and 16 multiparous (8 Holstein and 8 Jersey; 78 ± 15 d in milk; mean ± standard deviation) lactating dairy cows was conducted to determine how mitigating methane production by adding corn oil or calcium sulfate to diets containing reduced-fat distillers grains affects energy and nitrogen balance. A replicated 4 × 4 Latin square design with 35-d periods (28 d of adaption and 4 d of collections) was used to compare 4 different dietary treatments. Treatments were composed of a control (CON) diet, which did not contain reduced-fat distillers grain and solubles (DDGS), and treatment diets containing 20% (dry matter basis) DDGS (DG), 20% DDGS with 1.38% (dry matter basis) added corn oil (CO), and 20% DDGS with 0.93% (dry matter basis) added calcium sulfate (CaS). Compared with CON, dry matter intake was not affected by treatment, averaging 29.6 ± 0.67 kg/d. Milk production was increased for diets containing DDGS compared with CON (26.3 vs. 27.8 ± 0.47 kg/d for CON vs. DDGS, respectively), likely supported by increased energy intake. Compared with CON, energy-corrected milk was greater in DG and CO (30.1 vs. 31.4, 31.7, and 31.0 ± 0.67 kg/d for CON, DG, CO, and CaS, respectively). Compared with CON, the addition of calcium sulfate and corn oil to diets containing DDGS reduced methane production per kg of dry matter intake (22.3, 19.9, and 19.6 ± 0.75 L/kg per d for CON, CO, and CaS, respectively). Similarly, methane production per kilogram of energy-corrected milk was reduced with the addition of calcium sulfate and corn oil to diets containing DDGS (14.2, 12.5, and 12.4 ± 0.50 L/kg per d for CON, CO, and CaS, respectively). Compared with CON and CaS, the intake of digestible energy was greater for DG and CO treatments (57.7, 62.1, 62.0, and 59.0 ± 1.38 Mcal/d for CON, DG, CO, and CaS, respectively). Intake of metabolizable energy was greater in all treatments containing DDGS compared with CON (50.5 vs. 54.0 ± 1.08 Mcal/d for CON vs. DDGS, respectively). Net balance (milk plus tissue energy) per unit of dry matter was greater in CO (containing DDGS and oil) than CON (1.55 vs. 1.35 ± 0.06 Mcal/kg for CO vs. CON, respectively). Tissue energy was greater in DG and CO compared with CON (6.08, 7.04, and 3.16 ± 0.99 Mcal/d for DG, CO, and CON, respectively. Results of this study suggest that the addition of oil and calcium sulfate to diets containing DDGS may be a viable option to reduce methane production and in the case of oil also improve net energy balance in lactating dairy cows
Energy balance and diurnal variation in methane production as affected by feeding frequency in Jersey cows in late lactation
Methane (CH4) production of ruminants typically increases with increased dry matter intake (DMI). However, few studies have observed the effects of feeding multiple times a day and its effects on diurnal variation in CH4 production and energy balance in late-lactation dairy cattle. A study using headbox-style indirect calorimetry and 12 multiparous (225 ± 16.2 d in milk; mean ± SD) lactating Jersey cows was conducted to determine the effects of feeding twice daily on diurnal variation in CH4 production and total energy balance. A crossover design with 14-d periods (10 d of adaption and 4 d of collection) was used to compare 2 treatments. Treatments consisted of either once a day feeding (1×; 100% of feed given at 1000 h) or twice a day feeding (2×; 50% of feed given at 1000 h and the final 50% at 2000 h) with a common diet fed in both treatments. Dry matter intake was not different between treatments, with a mean of 16.9 ± 0.88 kg/d. Once a day feeding tended to have greater milk yield compared with twice a day feeding (21.2 vs. 20.4 ± 1.59 kg/d, respectively). Milk fat and milk protein percentage were not different, with means of 6.18 ± 0.20% and 3.98 ± 0.08%, respectively. Total CH4 production did not differ between treatments, with a mean of 402.1 ± 20.8 L/d. Similarly, CH4 per unit of milk yield and DMI was not different between treatments, with means of 20.5 ± 1.81 and 23.8 ± 1.21 L/kg, respectively. Feeding frequency did not affect diurnal variation of hourly CH4 production, with a mean of 17.1 ± 0.74 L/h. A trend was observed for a treatment × hour interaction. Methane production per hour increased after the second feeding for cattle fed twice versus once daily. Gross energy, digestible energy, metabolizable energy, and balance (milk plus tissue) per kilogram of DMI did not differ by feeding frequency, with means of 4.41 ± 0.01, 3.05 ± 0.03, 2.63 ± 0.03, and 1.32 ± 0.08 Mcal/ kg of DM, respectively. Metabolizable energy for maintenance was 146 kcal/kg of metabolic body weight, with an efficiency of converting metabolizable energy to net energy balance (milk plus tissue) of 76%. Nitrogen balance did not differ among treatments, with a mean balance of 17.3 ± 13.0 g/d. Therefore, total CH4 production and energy maintenance were not affected by feeding frequency. However, CH4 was variable throughout the day, and caution should be exercised when collecting CH4 samples at a limited number of time points because this may under- or overestimate total production
Energy balance and diurnal variation in methane production as affected by feeding frequency in Jersey cows in late lactation
Methane (CH4) production of ruminants typically increases with increased dry matter intake (DMI). However, few studies have observed the effects of feeding multiple times a day and its effects on diurnal variation in CH4 production and energy balance in late-lactation dairy cattle. A study using headbox-style indirect calorimetry and 12 multiparous (225 ± 16.2 d in milk; mean ± SD) lactating Jersey cows was conducted to determine the effects of feeding twice daily on diurnal variation in CH4 production and total energy balance. A crossover design with 14-d periods (10 d of adaption and 4 d of collection) was used to compare 2 treatments. Treatments consisted of either once a day feeding (1×; 100% of feed given at 1000 h) or twice a day feeding (2×; 50% of feed given at 1000 h and the final 50% at 2000 h) with a common diet fed in both treatments. Dry matter intake was not different between treatments, with a mean of 16.9 ± 0.88 kg/d. Once a day feeding tended to have greater milk yield compared with twice a day feeding (21.2 vs. 20.4 ± 1.59 kg/d, respectively). Milk fat and milk protein percentage were not different, with means of 6.18 ± 0.20% and 3.98 ± 0.08%, respectively. Total CH4 production did not differ between treatments, with a mean of 402.1 ± 20.8 L/d. Similarly, CH4 per unit of milk yield and DMI was not different between treatments, with means of 20.5 ± 1.81 and 23.8 ± 1.21 L/kg, respectively. Feeding frequency did not affect diurnal variation of hourly CH4 production, with a mean of 17.1 ± 0.74 L/h. A trend was observed for a treatment × hour interaction. Methane production per hour increased after the second feeding for cattle fed twice versus once daily. Gross energy, digestible energy, metabolizable energy, and balance (milk plus tissue) per kilogram of DMI did not differ by feeding frequency, with means of 4.41 ± 0.01, 3.05 ± 0.03, 2.63 ± 0.03, and 1.32 ± 0.08 Mcal/ kg of DM, respectively. Metabolizable energy for maintenance was 146 kcal/kg of metabolic body weight, with an efficiency of converting metabolizable energy to net energy balance (milk plus tissue) of 76%. Nitrogen balance did not differ among treatments, with a mean balance of 17.3 ± 13.0 g/d. Therefore, total CH4 production and energy maintenance were not affected by feeding frequency. However, CH4 was variable throughout the day, and caution should be exercised when collecting CH4 samples at a limited number of time points because this may under- or overestimate total production
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