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1.
Background: There is little information in the tropics with regard the comparative understanding of how an increased nitrogen supply in the rumen or in the intestines affects efficiency of nitrogen utilization in cattle. This study evaluated the effects of supplementation with nitrogenous compounds in the rumen, abomasum, or both on intake, digestibility and the characteristics of nitrogen utilization in cattle fed tropical forage. Four rumen- and abomasum-fistulated Nellore bulls(227 ± 11 kg) were used. Four treatments were evaluated: control, ruminal supplementation(230 g/d of supplemental protein in the rumen), abomasal supplementation(230 g/d of supplemental protein in the abomasum), and ruminal and abomasal supplementation(115 g/d protein in both the rumen and the abomasum).The basal forage diet consisted of Tifton 85 hay with a crude protein(CP) level of 78.4 g/kg dry matter. Casein was used as a supplement. The experiment was conducted using a 4 × 4 Latin square.Results: There were no differences between the treatments(P 0.10) with regard to forage intake. The intake and total digestibility of CP increased(P 0.01) with supplementation. The nitrogen balance in the body increased(P 0.01) and muscle protein mobilization decreased(P 0.01) with supplementation, regardless of the supplementation site.The efficiency of nitrogen utilization did not differ among the treatments(P 0.10).Conclusions: The supplementation of cattle fed tropical forage with protein in the rumen, abomasum, or both similarly increased the nitrogen accretion in animal, which reflects improvements on nitrogen status in animal body.  相似文献   

2.
Background: Increasing demand for high-value fish species and pressure on forage fish is challenging aquaculture to ensure sustainable growth by replacing protein sources in aquafeeds with plant and terrestrial animal proteins,without compromising the economic value and quality of the final fish product. In the present study, the effects of a plant protein-based diet(CV), two plant-based diets in which graded amounts of plan protein mixtures were replaced with Hermetia illucens meal alone(VH10) ...  相似文献   

3.
Health is maintained by a state of dynamic homeostasis in which nutrient intake and ex- penditure are of good balance. Therefore, it is important to know exactly the nutritional value of food sources, as well as the nutritional requirements of individuals, in order to achieve optimal nutrition. Considering the interaction between diet and individual back- ground, nutritional evaluation and recommendation has become a complicate issue needing further investigations. While traditional nutrition research has made significant progress in population nutrition, modern nutrition research is now becoming possible to focus on personalized nutrition in health promotion, disease prevention, performance improvement, and risk assessment of individual with the development of emerging omics technologies. This review tried to summarize the methods used in nutritional evaluation and recom- mendation as well as their applications. Though personal nutrition evaluation and recommendation are still not well-established, utilization of these advanced technologies may expand our knowledge in bioavailability and bioefficacy of diet ingredients, pathophysiological changes in response to dietary intervention, as well as nutrition-associated disease biomarkers discovery, and thus contributing to personalized nutrition.  相似文献   

4.
IntroductionCis-9,trans-11 CLA has been shown to be potentially healthpromoting CLA in many animal models.The C18∶1 trans-11 fatty acid (VA) is also desirable as a product flowing from the rumen,because the flow from the rumen of VA play a more important role than CLA in determining CLA concentration in animal tissues.The factors which affect CLA content in milk have been studied mainly in dairy cows and most factors are basically dietary factors,especially fat source(e.g.,plant oils,fish oil,et al.).Recently some researches showed that some plants or plant extracts could increase cis-9,trans-11 -CLA content in milk.The purpose of this experiment was to evaluate the effects of Chrysanthemum coronarium extract on in vitro Biohydrogenation of polyunsaturated fatty acids and fermentation characteristics of mixed rumen microorganisms.  相似文献   

5.
The offspring of super-multiparous sows face problems such as decreased growth performance, poor meat quality and even diseases in animal husbandry. Gama-aminobutyric acid(GABA) has long been known to promote growth and suppress inflammation, but little is known about the mechanisms. A total of 72 growing-finishing pigs from the 8th generation were randomly allotted to 2 groups with 6 replicates per treatment to receive a corn-soybean basal diet or the basal diet supplemented 20 mg/kg GABA for 6...  相似文献   

6.
<正>It is my great pleasure to write a few words here to congratulate the "new born baby",Journal of Animal Science and Biotechnology (JASB),which is the first Chinese journal in the field of animal science published in English.JASB is a quarterly journal supported by Chinese Association of Animal Science and Veterinary Medicine (CAAV). The purpose of the journal is to introduce Chinese research achievements of animal science and technology world over,and to strengthen academic communication between China and other countries.Subjects of the journal are related widely of animal science such as:animal genetics and breeding,reproduction and physiology,biotechnology,nutrition and feed processing,environmental protection and grassland management. Animal science and animal production in China have been developed rapidly during last 20 years.China has become the largest meat and egg producer in the world. However,at meantime we know clearly that the development of China's animal science and biotechnology is still behind the world advanced level.We have to work hard,and to learn more from developed countries.Let us do all our efforts to make the "new born baby" growing healthy and strong.  相似文献   

7.
Grassland is a major vegetation type in Xinjiang Province,and is an important component of carbon source-sink calculations. It is therefore important to ecological management decisions to understand the factors driving changes in grassland quality and likely future trends in those changes. We used geographic information maps to eliminate the interference of human activities and determine changes in grassland status and areas of stable grassland from 1980 to 2020,and analyzed changes in grassland quality and its response to climate change using data such as normalized vegetation index(NDVI),vegetation net primary productivity(NPP),and meteorological data,among others. We here estimate changes in grassland quality in Xinjiang and predict grassland quality changes from 2021 to 2040 using the Thornthwaite Memorial model and other models. We found that:1) The grassland quality in Xinjiang was generally increasing,with a statistically significant rate of ongoing increase. The grassland cover and quality in mountainous areas of Xinjiang was high,while that at the desert edge was low. 2)The main driving forces for grassland quality changes in Xinjiang are temperature and precipitation. The correlation between grassland quality and precipitation was positive. Temperatures exceeding a certain limit were found to inhibit grassland quality. Sensitivity to temperature and precipitation decline was found to be greater when vegetation cover was lower. 3)The grassland quality and its temporal and spatial changes in Xinjiang can be reflected by climatic productivity. The lower the grassland cover,the stronger was the link between grassland quality and climate factors. 4)Under currently predicted climate change scenarios,the quality of low-cover grassland will be improved in the future,while the quality of other categories will tend to decrease. This information on grassland quality in Xinjiang and its predicted future trends can assist in formulating ecological protection measures and in other ways,such as compilation of carbon stock inventories. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.  相似文献   

8.
Recent developments suggest the use of other gases such as carbon dioxide(CO_2) to estimate methane(CH_4)emissions from livestock,yet little information is available on the relationship between these two gases for a wide range of animals.A large respiration calorimeter dataset with dairy cattle(n=987 from 30 experiments)was used to investigate relationships between CH_4 and CO_2 production and oxygen(O_2)consumption and to assess whether the predictive power of these relationships could be improved by taking into account some dietary variables,including forage proportion,fibre and metabolisable energy concentrations.The animals were of various physiological states(young n=60,dry cows n=116 and lactating cows n=811)and breeds(Holstein-Friesian cows n=876,Jersey×Holstein-Friesian n=47,Norwegian n=50 and Norwegian×Holstein-Friesian n=14).The animals were offered forage as a sole diet or a mixture of forage and concentrate(forage proportion ranging from 10 to 100%,dry matter basis).Data were analysed using a series of mixed models.There was a strong positive linear relationship between CH_4and CO_2,and observations within an experiment were very predictable(adjusted R~2=0.93).There was no effect of breed on the relationship between CH_4 and CO_2.Using O_2 instead of CO_2 to predict CH_4 production also provided a very good fit to the observed empirical data,but the relationship was weaker(adjusted R~2=0.86).The inclusion of dietary variables to the observed CO_2 emissions,in particular forage proportion and fibre concentration,provided a marginal improvement to the prediction of CH_4.The observed variability in the CH_4:CO_2 ratio could only marginally be explained by animal physiological state(lactating vs.dry cows and young cattle)and dietary variables,and thus most likely reflected individual animal differences.The CH_4:CO_2 ratio can therefore be particularly useful to identify low CH_4 producing cows.These findings indicate that CO_2 production data can be used to accurately predict CH_4 emissions to generate large scale data for management and genetic evaluations for the dairy industry.  相似文献   

9.
The rodent damage threshold and the rodent economic threshold are indicators that must be clearly defined in the practice of grassland rodent prevention and control. Different grassland types or different utilization methods of the same grassland type have completely different values for these two indicators. The damage threshold is the population density of pests at which the grassland is obviously compromised, and the economic threshold is the population density at which further pest population increases will cause economic losses. The Alxa desert region is ecologically fragile, and rodents are endemic. This study selected continuous grazing areas and prohibited grazing areas in the desert area of Alxa Left Banner and from 2015 to 2019 to investigated the species and density of pests using the ‘mark and recapture’ method, together with sampling to investigate the aboveground plant biomass in the sample area in August. The measured rodent unit densities and their daily food intakes were used to estimate the amount of forage loss, and a regression equation was used to obtain a fitted relationship between the rodent density and the ratio of forage loss. It was found that: 1) The fitted curves for the ratio of pest density and forage loss in the continuous and prohibited grazing areas took the form of logistic three-parameter, S-shaped curves. 2) According to the regression equation, the damage threshold in continuous grazing areas was 26 standard rodent units·ha-1 and the economic threshold was 39.3 standard rodent units·ha-1. In prohibited grazing areas, the damage threshold was 33.2 standard rodent units·ha-1 and the economic threshold was 30.2 standard rodent units·ha-1. Thus, the economic threshold pest density of continuous grazing areas was slightly higher than that of prohibiting grazing areas. © 2022 Editorial Office of Acta Prataculturae Sinica. All rights reserved.  相似文献   

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11.
Background: The pork industry faces unprecedented challenges from disease, which increases cost of production and use of antibiotics, and reduces production efficiency, carcass quality, and animal wellbeing. One solution is to improve the overall resilience of pigs to a broad array of common diseases through genetic selection. Behavioral changes in feeding and drinking are usually the very first clinical signs when animals are exposed to stressors such as disease. Changes in feeding and drinking...  相似文献   

12.
In complex feed structures, there exist main chemical functional groups which are associated with nutrient utilization and availability and functionality. Each functional group has unique molecular structure therefore produce unique molecular vibration spectral profile. Feed processing has been used to improve nutrient utilization for many years. However, to date, there was little study on processing-induced changes of feed intrinsic structure and functional groups on a molecular basis within intact tissue. This is because limited research technique is available to study inherent structure on a molecular basis. Recently bioanalytical techniques: such as Synchrotron Infrared Microspectroscopy as well as Diffuse Reflectance Infrared Fourier Transform molecular spectroscopy have been developed. These techniques enable to detect molecular structure change within intact tissues. These techniques can prevent destruction or alteration of the intrinsic protein structures during processing for analysis. However, these techniques have not been used in animal feed and nutrition research. The objective of this review was show that with the advanced technique, sensitivity and responses of functional groups to feed processing on a molecular basis could be detected in my research team. These functional groups are highly associated with nutrient utilization in animals.  相似文献   

13.
Epigenetics provides a molecular mechanism of inheritance that is not solely dependent on DNA sequence and that can account for non-Mendelian inheritance patterns. Epigenetic changes underlie many normal developmental processes, and can lead to disease development as wel. While epigenetic effects have been studied in wel-characterized rodent models, less research has been done using agricultural y important domestic animal species. This review wil present the results of current epigenetic research using farm animal models(cattle, pigs, sheep and chickens). Much of the work has focused on the epigenetic effects that environmental exposures to toxicants, nutrients and infectious agents has on either the exposed animals themselves or on their direct offspring. Only one porcine study examined epigenetic transgenerational effects; namely the effect diet micronutrients fed to male pigs has on liver DNA methylation and muscle mass in grand-offspring(F2 generation). Healthy viable offspring are very important in the farm and husbandry industry and epigenetic differences can be associated with production traits. Therefore further epigenetic research into domestic animal health and how exposure to toxicants or nutritional changes affects future generations is imperative.  相似文献   

14.
Background: Play behavior has been proposed as a new potential indicator of animal welfare. Animals play only if they are in a relaxed state. Play may improve adaptability to challenging environments which may be of interest in the breeding objective. Little information is available on play behavior in livestock species. The aim of the present study is to investigate whether play behavior in post-weaned piglets can be induced instantly in the presence of additional space and whether play markers are body weight, sex, and litter dependent, it is investigated whether playfulness is elicited by the moment or if this measure is consistent over different days. Methods: Thirty two piglets from four litters were released into a corridor and video recorded for eight min at 37, 41, 44 and 48 d of age. The first test was considered as an adjustment period and was not included in the analysis. In the second to the fourth test, joyful brusque movements (jumping, turning and running) were recorded with a camera and total number of movements (JOY#) and total time (JOYtime) were estimated individually. Animals were weighed at 41 d of age. Results: Females had higher scores of JOY# and JOYtime than males but this was significant only for JOY# at 41 d of age (P 〈 0.05). The effect of age was highly significant both for JOY# and JOYtime (P 〈 0.01). Animals with a higher JOY# and JOYtime also expressed a higher JOY# and JOYtime in the other tests, but this was significant only between 44 and 48 d of age (P〈 0.01). Body weight at 41 d of age was not significantly related to JOY# and JQYtime in any of the tests. Conclusions: Locomotor play was induced instantly by the provision of increased space allowance. Litter origin had a significant effect on play behavior. In addition, locomotor play scores were consistent between two of the three tests.  相似文献   

15.
Background Mastitis not only deteriorates the composition or quality of milk, but also damages the health and productivity of dairy goats. Sulforaphane(SFN) is a phytochemical isothiocyanate compound with various pharmacological effects such as anti-oxidant and anti-inflammatory. However, the effect of SFN on mastitis has yet to be elucidated.This study aimed to explore the anti-oxidant and anti-inflammatory effects and potential molecular mechanisms of SFN in lipopolysaccharide(LPS)-induced pri...  相似文献   

16.
Dietary fiber, resistant to host-mediated digestion in the small intestine due to lack of endogenous enzymes, impacts many facets of animal health and is associated with gut development especially in young monogastrics. Furthermore, it can be used as in-feed antibiotic alternative. Chicory (Cichorium intybus L.) forage with high content of pectin (uronic acids as building blocks) is a novel class of dietary fiber that is chemically different from cereal grains (with high content of arabinoxylans). In the present study, we investigated effects of dietary inclusion of chicory forage on digestibility, gut morphology and microbiota in broilers and young pigs. In the chicken experiment, 160 1-d old broiler chicks were fed 3 nutritionally balanced diets for 30 d including a cereal-based diet and 2 diets with part of the cereals substituted with 60 and 120 g/k9 chicory forage (CF60 and CF120], whereas in the pig experiment, 18 seven-wk old Yorkshire pigs were fed 3 diets for 18 d including a cereal-based diet and 2 diets with 80 and 160 g/kg chicory forage inclusion (CF80 and CF160). Our results showed that young pigs were capable to utilize chicory forage well with higher total tract apparent digestibility (TTAD) of all fiber fractions, particularly uronic acid, compared with the control (P 〈 0.01). In contrast, a decreased TTAD of all fiber fractions was observed in chickens fed on diet CF120 (P 〈 0.05). Moreover, diet induced changes in gut morphology were observed in the large intestine of chickens. The alteration of cecal mucosal thickness was further positively correlated with TTAD of non-starch polysaccharides (NSP) and its constituent sugars (P 〈 0.05). In addition, in pigs, terminal restriction fragment length polymorphism (T-RFLP) analysis of intestinal microbiota revealed substantial dietary effects (cereal control diet vs. chicory forage inclusion) on the relative abundance of 2 dominant bacterial phylotypes (Prevotella sp. vs. Roseburia sp.) respective  相似文献   

17.
This experiment was conducted to determine the effects of feeding mustard protein concentrate on nutrient digestibility and the performance of broiler chickens.A total of 180,day-old,male broiler chickens,weighing an average of 52.8 ± 0.6 g,were randomly assigned to one of six dietary treatments in a randomized block design.The control diet was based on wheat and soybean meal and contained 15% canola meal.The experimental diets contained 3%,6%,9%,12% or 15% mustard protein concentrate added at the expense of canola meal.The digestibility of crude protein and energy declined linearly(P0.01)with increasing levels of mustard protein concentrate.In addition,weight gain and feed intake were linearly(P0.01)reduced as the level of mustard protein concentrate in the diet increased.Feed conversion was also negatively affected(P0.01)by mustard protein concentrate while mortality did not differ among treatments.The results of the present experiment provide a strong indication that there is a factor or factors present in mustard protein concentrate which negatively affects broiler performance.The process through which the protein in mustard seed is concentrated from mustard meal may concentrate some of the anti-nutritional factors found in mustard.Previous research has reported an increase in the concentration of phenolic compounds in protein isolates from mustard and this may be the cause of the reduction in performance as the level of mustard protein concentrate in the diet increased.Further research should be conducted to test this hypothesis.  相似文献   

18.
19.
Background: In rumen fermentation, fumaric acid(FA) could competitively utilize hydrogen with methanogenesis to enhance propionate production and suppress methane emission, but both effects were diet-dependent. This study aimed to explore the effects of FA supplementation on methanogenesis and rumen fermentation in goats fed diets varying in forage and concentrate particle size.Methods: Four rumen-cannulated goats were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments: low or high ratio of forage particle size: concentrate particle size(Fps:Cps), without or with FA supplementation(24 g/d). Fps:Cps was higher in the diet with chopped alfalfa hay plus ground corn than in that with ground alfalfa hay plus crushed corn.Results: Both increasing dietary Fps:Cps and FA supplementation shifted ruminal volatile fatty acid(VFA) patterns toward more propionate and less acetate in goats. An interaction between dietary Fps:Cps and FA supplementation was observed for the ratio of acetate to propionate(A:P), which was more predominant when FA was supplemented in the low-Fps:Cps diet. Methane production was reduced by FA, and the reduction was larger in the low-Fps:Cps diet(31.72%) than in the high-Fps:Cps diet(17.91%). Fumaric acid decreased ruminal total VFA concentration and increased ruminal p H. No difference was found in ruminal DM degradation of concentrate or alfalfa hay by dietary Fps:Cps or FA. Goats presented a lower ruminal methanogen abundance with FA supplementation and a higher B. fibrisolvens abundance with high dietary Fps:Cps.Conclusions: Adjusting dietary Fps:Cps is an alternative dietary model for studying diet-dependent effects without changing dietary chemical composition. Fumaric acid supplementation in the low-Fps:Cps diet showed greater responses in methane mitigation and propionate increase.  相似文献   

20.
Recent technological advances mean that samples from animal experiments may be analysed more cheaply, more easily and with a much greater return of data than previously. Research groups are frequently faced with a choice of continuing to use established technology in which they may have made a significant investment of time and resources, and have significant amounts of reference data, or switching to new technology where reference data may be limited. Apart from cost, the choice needs to be based on a comparison between the increase in data available from future experiments by switching and the value of comparison with reference data from historical experiments analysed with earlier technology. One approach to this problem is to ensure that sufficient quantity and variety of samples are taken from each experiment and appropriately stored to allow re-establishment of a sufficiently large reference set and to avoid the need to repeat animal experiments. The establishment of ‘biobanks' of experimental material will require funding for infrastructure, consistent storage of metadata and, importantly,horizon-scanning to ensure that samples are taken appropriately for techniques which will become accessible in future. Such biobanks are a recognised resource in human medicine, where the value of samples increases as more analysis is carried out and added to the metadata.  相似文献   

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