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The effect of feeding urea-molasses blocks (UMB) on the growth and gastrointestinal nematode parasitism of dairy weaner calves grazing on the same pasture was investigated on a farm in Thika District, central Kenya. Twenty-six female calves, with an average age of 9 months, were initially treated orally with albendazole (10 mg/kg body weight) and assigned into two groups: animals in group I were fed urea-molasses blocks (UMB) prepared using a cold process and those in group II were the controls. The UMB were given in the evening, when the animals returned from grazing, and were consumed during the night at a rate of 550 g/head per day. Supplementation was undertaken on three occasions for three consecutive months, between July and August 1999, and between January and March and July and September 2000. The body weights of the calves and the faecal egg counts were measured monthly and larval cultures were performed on positive faecal samples from each group. Significant differences (p < 0.05) were found in the cumulative weight gains of the two groups of calves from September onwards. The UMB group averaged (+/- SD) 311.2 +/- 14.9 g/day over the study period, while the control group averaged 235.7 +/- 23.5 g/day; the UMB group also reached breeding weight earlier (p < 0.05) than the control group. There was no significant difference (p > 0.05) in the faecal egg counts between the groups, the predominant genera of gastrointestinal nematodes in faecal cultures being Haemonchus spp. and Trichostrongylus spp. Other nematodes were Cooperia spp., Bunostomum spp. and Oesophagostomum spp.  相似文献   

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Rapid conversion of rural land to exurban development and the ensuing impacts on natural resources have been well-documented, but information about exurban landowners is lacking. To address this knowledge gap, we surveyed exurban landowners in six Wyoming counties and documented demographic characteristics, motivations, knowledge, and attitudes about natural resources and land management. The overall response rate was 55.6%. Generally, respondents were of retirement age, had lived in Wyoming for about 13 yr, and were raised in areas with a population < 10 000. Wyoming respondents lived in exurbia for the lifestyle and aesthetic values and did not expect economic gains from their property. Most respondents had knowledge about, and interest in, invasive species, water quality, landscaping, and gardening. More than half of respondents (54%) had never looked for information regarding land management. Information from this study can be used to strengthen the development and delivery of educational programs. Programs that focus on water quality or weed control likely will appeal to more exurban landowners than those that focus solely on grazing management. Our findings provide an accurate characterization of this audience and their motivations and attitudes regarding land management, and suggest that using a multipronged approach for outreach efforts, which includes both cost- and time-efficient ways to conduct important land management practices, might increase participation in educational programs.  相似文献   

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The ITRM of liver, one of the important indexes of tissue respiratory metabolism in yak, is higher than other tissues. The relationship of ITRM and time belongs to the equation y = aebt. The ITRM of each tissue in reciprocal yaks were significant(P<0.05) lower than that of the domestic yaks which showed that the adaptability to hypoxia of the reciprocal yaks were more powerful than the domestic yaks.  相似文献   

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The appeal of cost savings and faster results has fish and wildlife management agencies considering the use of Internet surveys instead of traditional mail surveys to collect information from their constituents. Internet surveys, however, may suffer from differential age-related response rates, potentially producing biased results if certain age groups respond to Internet surveys differently than they do to mail surveys. We examined this concern using data from a mixed-mode angler survey conducted in South Dakota following the 2011 fishing season. Results indicated that young anglers (16–18) had the lowest return rates and senior anglers (65+) had the highest, regardless of survey mode. Despite this consistency in response rates, we note two concerns: (a) lower Internet response rates and (b) different age groups represented by the Internet and mail survey samples differed dramatically. Findings indicate that constituent groups may be represented differently with the use of various survey modes.  相似文献   

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Hair and feathers are composed of keratin and are indigestible, inalimental and unpalatable for carnivores. However, carnivores often ingest hair and feathers during feeding or when grooming. We hypothesized that ingestion of hair and feathers changes species diversity and relative abundance of bacteria in the gut of carnivores. To test this hypothesis, we added disinfected poultry down feathers to the normal diet of captive Arctic foxes (Alopex lagopus). We then used fluorescently labeled terminal restriction fragments (T‐RFs) to examine changes in fecal bacterial diversity and abundance. The results showed that the number of bacterial species increased significantly after feather ingestion, but that total abundance was unchanged. This demonstrated that addition of disinfected feathers to the diet stimulated increased production among less abundant bacteria, resulting in a balancing of relative abundance of different bacterial species, or that some newly‐ingested microbial species would colonize the gut because a suitable microhabitat had become available. This implies that the overall production of bacterial metabolites would be made up of a greater range of substances after feather ingestion. On one hand, the host's immune response would be more diverse, increasing the capacity of the immune system to regulate gut microflora. On the other hand, the animal's physiological performance would also be affected. For wild animals, such altered physiological traits would be subjected to natural selection, and, hence, persistent geographic differences in the character of ingested feathers or fur would drive speciation.  相似文献   

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This experiment was conducted to study the effects of Bacillus amylolyticus on rumen dry matter digestibility, fermentation parameters and metabolites of dairy cows. Experiment 1: six dairy cows with permanent fistula and had the similar parity (2 to 3 fetuses), body weight [(662 ±57) kg], lactation days [(160 ± 22) d] and milk yield [(36.1 ±3.8) kg / d], were randomly divided into 3 groups with 2 cows per group. Using 3 ×3 Latin square design, each group was extra fed 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, the trial period was 3 periods, 13 days for each period, including 10 days for the pre-trial period and 3 days for the trial period. At the beginning of the trial period, the rumen dry matter digestibility of cows was measured by nylon bag method. Experiment 2: thirty dairy cows with similar parity [(2.5 ±0.3) fetuses], initial body weight [(559.2 ± 7. 4) kg], milk yield [(35. 2 ± 1. 5) kg / d] and lactation days [(99 ± 22) d] were randomly divided into three groups with 10 cows in each group. Cows in the 3 groups were extra fed with 0 (control group), 5 ×109 and 5 ×1010 CFU / d Bacillus amylolyticus, respectively. The pre-trial period was 10 days and the trial period was 42 days. The rumen fluid was collected on the last day of the trial period, and the rumen fermentation parameters and metabolites were determined. The results showed as follows: compared with the control group, 1) supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 12, 24, 36, 48 and 72 h (P <0.05), supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly improve the rumen dry matter digestibility of dairy cows at 36 and 48 h (P <0.05); 2) supplementary feeding of 5 ×109 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid, butyric acid, isovaleric acid, valeric acid, total volatile fatty acid and microbial protein in the rumen of dairy cows (P < 0. 05), supplementary feeding of 5 × 1010 CFU / d Bacillus amylolyticus could significantly increase the contents of isobutyric acid and isovaleric acid in the rumen of dairy cows and significantly reduce the rumen acetic acid / propionic acid (P < 0. 05), supplementary feeding of 5 ×109 and 5 ×1010 Bacillus amylolyticus had no effects on rumen pH and ammonia nitrogen content (P >0.05); 3) eleven metabolic pathways related to differential metabolites were detected, and ascorbic acid and alginate metabolism were significantly enriched (P < 0. 05) . In conclusion, Bacillus amylolyticus can increase the rumen dry matter digestibility, and improve the rumen fermentation function of dairy cows by affecting the content of rumen metabolites. By comprehensive analysis, supplementary feeding of 5 × 109 CFU / d Bacillus amylolyticus can achieve better effect. © 2023 Authors. All rights reserved.  相似文献   

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1. The cause of the sticky droppings and poor performance that can occur when barley is fed to poultry was investigated.

2. The problems could be overcome by water‐treatment of the barley or by addition of β‐glucanase.

3. The problems appear to be caused by a viscous factor, which is hydrolysed by β‐glucanase. Water‐treatment allows hydrolysis by enzymes in the barley.

4. Heat‐treatment of barley denatures hydrolytic enzymes and prevents reduction in viscosity.  相似文献   


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The highly centralized management of rangelands in northwest Iran has caused their degradation. Rangeland Management Cooperatives (RMCs) have been taken into account by the Iranian researchers and practitioners as the best mode of managing and tackling these resources. In this regard, stakeholders’ participation (i.e., the rangers) in such institutions is a substantial issue because without their close collaboration, any management scheme is likely to fail or succeed partially. Therefore, this study investigates the rangers’ participation in RMCs using the theory-triangulation method. We developed the main research question: how the explanatory variables, extracted from the social-psychological models, influence rangers’ participation in RMCs. A sample of 200 rangers participated in the survey method, of which we received 179 completed self-reported questionnaires. The reliability of the questionnaire was calculated using the Confirmatory Factor Analysis and Kuder-Richardson 21, the metrics that measure the consistency of items in indicator variables with the interval and binary scales, respectively. The results of path analysis unveil that job satisfaction and progressivism have a direct effect on participation, and the improved economic conditions of industries developed by the RMCs, good intrarelation, fatalism, progressivism, optimism, and cost-benefit indirectly influence participation via job satisfaction. On the basis of these results, it is concluded that to increase rangers’ participation in RMCs, which is a key factor in preventing the degradation of rangelands, RMCs’ officials need to improve the local industries benefiting from the rangelands and upgrade intracommunication skills via training. It is also suggested that all rangers, even those with fatalistic beliefs, need to be included in RMCs’ participatory activities. Finally, it is needed to assess progressivist rangers’ needs, promote optimism, and visualize the economic, social, and conservation benefits of the participation in RMCs.  相似文献   

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Grain processing (e.g. grinding, steaming, pelleting, flaking) has been reported to modify the incidence of ruminal disturbances in feedlot cattle. This study investigated the effects of two grain processing methods widely used in Spanish feedlots (grinding and pelleting) on animal performance, blood acid–base balance, blood electrolyte levels and serum lactate in a 140-day feedlot experiment with double-muscled Belgian Blue steers. The main aim of the study was to evaluate the way in which these two feeds modify blood acid–base balance, which is closely associated with ruminal pH. In light of our results we conclude that the animals that received the pelleted feed showed a more stable acid–base balance over time than those fed a ground feed. Nevertheless, higher levels of L-lactate and lower base excess (BE) and HCO3 values for cattle fed pelleted grain reflect a greater risk of grain-acid overload.  相似文献   

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The experiment was aimed to study the effects of herbal compound Outikang on antibody titer of foot and mouth disease vaccine type O,type A and type Asia Ⅰ,serum levels of ten cytokines and biochemical indices. 200 healthy adult cows were averagely divided into drug group and blank control group. Vaccinating the cows with FMD triplex vaccine when Outikang was given to the cows of drug group for 7 d running and then got the blood of all the cows on 0, 14, 28 and 56 d, respectively. Then blood biochemical examination, vaccine effectiveness and serum levels of cytokines were performed. The results showed that there were no significant differences in antibody titer of FMDV between blank control group and drug group on 0, 28 and 56 d after vaccination (P>0.05), while on 14 d the effect of Outikang on antibody titer of FMDV reached extremely significant level (P<0.01). Compared with blank control group, the contents of T-Bil in drug group was significantly decreased on 0 and 28 d (P<0.05), while it was extremely significantly decreased on 56 d (P<0.01).Compared with blank control group, the contents of Glu had significant difference on 28 and 56 d (P<0.05).The contents of P had extremely significant difference on 0 d (P<0.01), which was within the normal range. On 14 d after vaccination, the content of CD4 significantly increased in the drug group comparing to those in blank control group (P<0.05). On 28 d after vaccination, the content of CD4, IL-2, IL-6, IL-10, IL-12, IL-18 and IFN-γ extremely significantly increased in the drug group comparing to those in blank control group (P<0.01). On 56 d after vaccination, the contents of IL-6 and IL-12 extremely significantly increased in the drug group comparing to those in blank control group (P<0.01), while the content of CD4, IL-2, IL-4 and IL-18 significantly increased (P<0.05). Therefore, Outikang could significantly rise the antibody titer of foot and mouth disease vaccine type O, type A and type Asia Ⅰ.While it had no damage to the liver and kidney functions and had cholagogue effect, and it could enhance cellular immunity and humoral immunity function obviously.  相似文献   

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