Wastewater from aquaculture has attracted wide attention as one of the sources of agricultural non-point source pollution, and the management of aquaculture wastewater has become a current research hotspot. In order to understand the mechanism of aquaculture wastewater purification and enhance the purification technology efficiency, this paper introduces the current status, hazards, and related control policies of aquaculture pollution in China, and reviews the aquaculture wastewater purification technologies developed in the past two decades. Finally, the research direction of aquaculture wastewater is discussed to put forward the possibility of strengthening the sedimentation unit, and using new materials and microorganisms to intensify the purification system.

The author described the development status of special economic animal breeding industry for recent years. Mainly special economic animal breeding in our country, for example animal fur (fox, raccoon dog, mink), deer (cervus nippon, wapiti), rare birds in areas such as industrial development, scientific research and innovation breakthrough, achieved significant results, international influence and future development the trend was summarized. The author pointed out that the field of special economic animal breeding in China has been in the field of scientific research achievements, the influence in the world, and the gap between other countries and China’s special economic animal breeding industry in the future research. The author pointed out the direction for China’s special economic animal breeding industry sustainable development.

To provide scientific reference for illuminating the pollution status of aquaculture in China, based on the existed pollution discharging coefficients and breeding yield of 2014, we calculated and analyzed the total discharge amount of major aquacultural pollutants.Due to the lack of correlation data, this paper chooses the year of 2014 as the year of measurement. The results showed that the main pollution discharge amount of total nitrogen, ammonia nitrogen (NH3-N), total phosphorus, chemical oxygen demand (COD), copper and zinc in aquaculture in 2014 was 68.342 × 104, 16.660 × 104, 13.769 × 104, 164.154 × 104, 253.746 and 729.842 t, respectively. COD and NH3- N accounted for about 7% of the total wastewater amount in China.. Due to differences in yield, breeding way and variety, pollutant discharge amount from freshwater aquaculture was much higher than that of marine aquaculture. In addition, to promote the sustainable development of aquaculture in China, we put forward suggestions such as controlling freshwater aquaculture production, adjusting breeding way, developing healthy and ecological breeding technology and promoting research on related systems.

Welfare rearing of laying hens combines welfare with production of laying hens, and is the developing trend of laying hen industry. At present, cage rearing is dominant in China, welfare rearing of laying hens needs to be carried out. First, we clarified the definition and modes of welfare rearing of laying hens. Second, we summarized the current status of welfare rearing from the following aspects, i.e. enrichment of rearing environment, rearing equipment, rearing density, management (beak broken, forced moulting, ventilation, light, etc.), transportation, and slaughter. Finally, we pointed out the existing problems for welfare rearing of laying hens and put forward corresponding countermeasures, aiming to provide a reference for the welfare rearing and promote the healthy and stable development of laying hen industry in China.

Animal welfare in livestock husbandry influenced quality and safety of animal-derived food and then did people’s health. The development of animal welfare in China was lagging behind that in western developed countries in many aspects such as people’s attitude toward animal welfare, legislation, scientific research, education and production practices, which were related to the development level of livestock husbandry and also to national conditions related at present in China. In recent years, with consumers’ attention to quality and safety of livestock products, the government, academia and enterprises have begun to value animal welfare in livestock breeding. The healthy breeding guided by the concept of animal welfare would develop rapidly and the sound welfare labeling mechanism and legal norms would be established to guide people to pay close attention to animal welfare.

The traditional aquaculture pattern can easily cause water pollution and waste of water resources. In order to reach the goal of healthy aquaculture, pond recirculating aquaculture system (PRAS) takes measures to purify water by using power flow purification and bioremediation techniques under the guidance of circular economy, such as establishing artificial wetland to form a sustainable development model. In this study, we summarized the construction of the three main models of PRAS and their effects on water purification, and analyzed the main problems in the operation of the system. The existing studies showed that the average removal rates of TN, TP, NH4+-N, CODMn, and NO2--N were basically maintained at 60%. Besides, we analyzed the factors such as the ratio of purification area to pond area as well as the effects of the substrate, plant, pH and temperature in the purification unit. This study can provide a reference for further in-depth research on PRAS.

The rise and development of shrimp aquaculture industry is the result of market demand and technological progress. Based on the data of China fisheries yearbook and FishstatJ database from FAO, the author made a qualitative and quantitative analysis of China’s overall scale of shrimp aquaculture from 1958 to 2015, the changes of the indicators including breeding species, yield per unit area, production cost and income, and the changes of technological path for shrimp breeding, disease prevention and control, nutritional needs, diet formulation and delicacy management. The study could clarify the evolution rule and provide reference for formulating a sustainable development strategy of shrimp aquaculture.

To investigate the status and pollution situation of livestock and poultry breeding industry in Yiwu City and put forward the corresponding measures, annual total excrement from main livestock/poultry and nitrogen, phosphorus content in which were evaluated based on the agricultural pollution census data and poultry waste emission coefficient in urine. The study showed that, gross livestock/poultry excrement in 2007 comprises of 16.6×104 tons of feces and 48.5×104 tons of urine. The total livestock/poultry excrement contained 0.18×104 tons total N, 348.59 tons total P, 3.16×104 tons COD, 1.10×104 tons Cu, and 2.07×104 tons Zn. Among the main livestock/poultry, pigs excreted the highest amount of feces, accounting for 78.3% of the total excrement; the livestock/poultry urine was also produced by pigs, accounting for 99.8%. The highest amount of livestock/poultry excrement came from Yiting town, accounting for 39.4%.

To gain an in-depth understanding of the residue characteristics and risk assessment of mercury in the pond culture environment of Eriocheir sinensis, a total of 14 samples of water bodies and sediment from 7 Eriocheir sinensis aquaculture ponds were collected in Wuxi of Jiangsu. The residue levels of mercury in different forms were analyzed by liquid chromatography-inductively coupled plasma mass spectrometry (LC-ICP-MS), and the risk of mercury residues was assessed by the single-factor method. The results showed that the mercury content in water bodies ranged from ND (not detected) to 18.20 μg/L, mainly inorganic mercury (Hg²⁺), and other forms included methylmercury (MeHg) and ethylmercury (EtHg). The mercury content in sediment environment ranged from 0.01 to 0.022 μg/g, in which the content of inorganic mercury decreased and the content of methyl mercury increased. Compared with NYT 5361-2016 Environmental Conditions of Pollution-Free Agricultural Products - Freshwater Aquaculture Origin, it was found that the mercury content in the water body exceeded the standard in 5 samples, and the exceeding rate was 71.43%; the mercury content in the sediment environment exceeded the standard in 1 sample, and the exceeding rate was 14.29%. Further research on the ecological risk of water inorganic mercury residues to Eriocheir sinensis showed that the risk quotient ranged from 0 to 0.05, far below 1, indicating that the mercury residues in the water body did not affect the safe growth of Eriocheir sinensis. The detection of heavy metal mercury in aquaculture water is of great significance to the healthy growth of Eriocheir sinensis and food safety.

Freshwater pond aquaculture is the main mode of aquaculture in China, its industrial structure optimization and upgrading is of great significance. The study introduced current status and main species of freshwater pond aquaculture in China, expounded the changes of freshwater pond aquaculture in terms of species structure, culture technology and culture methods, and outlined the main modes of freshwater pond aquaculture in China at present. The study also discussed main problems of freshwater pond aquaculture from eight aspects: species, feed, diseases, environment, aquaculture equipment, aquatic product quality and safety, and aquaculture management, and put forward suggestions on each of these problems, in order to provide ideas for the healthy, high-yield, environmental protection and standardized development of modern freshwater pond aquaculture in China.

To understand the nutrient composition of fish muscle under the condition of recirculating aquaculture system, and to study the quality control of fish, in this study, the nutrient composition, amino acid and fatty acid composition of Russian sturgeon (Acipenser gueldenstaedtii) muscle were compared in recirculating aquaculture system and in ponds under simulated wild conditions. The results showed that there was no significant difference in the general nutrient composition between the two conditions. 17 kinds of amino acids were detected, and there was no significant difference in the content of each component of amino acid between the two conditions. Amino acid score (AAS) and chemical score (CS) showed that the first restrictive amino acid in recirculating aquaculture system was methionine, the lysine scored the highest among essential amino acids, and essential amino acid index (EAAI) in recirculating aquaculture system was higher than that in pond aquaculture system. The circulating water group detected 20 kinds of fatty acids and the pond group detected 14 kinds of fatty acids, there was no significant difference in the total amount of fatty acids between the two groups. There were significant differences in the composition of fatty acids. Among them, DHA was significantly higher in the circulating water group than in the pond group. In conclusion, the nutritive value of the muscle of Russian sturgeon under the recirculating aquaculture system is no less than that under the simulated wild condition pond.

Cyanobacteria bloom is a serious problem in aquaculture. In this paper, the formation of cyanobacterial blooms, the harm of cyanobacteria bloom, and the treatment methods were summarized. Among all the treatments, using the microorganism is a kind of effective method. Then paper explained the mechanism of control algae echanism with Bacillus and discussed future application of Bacillus in the controlling harmful algal and repairing water environment.

Starting from the problems faced by the sustainable development of domestic aquaculture industry, we independently developed the ‘biomass refining’ technology and the complete set of equipment, extracted water-soluble organic carbon materials with high activity and small molecules from natural plants, and introduced them into aquaculture. Combined with years of research and practice, we analyzed the economic and social benefits, and proved that the plant derived small molecule organic carbon had high activity and could play an important role in aquaculture.

Innovative tools play a crucial role in the technology development of traditional Chinese veterinary medicine, and the systematic summarizing and application study of these tools could provide ideas for the development of modern Chinese veterinary medicine. In this paper, we sorted out the evolutionary history of traditional Chinese veterinary medicine and analyzed the effect of innovative tools on promoting the advancement of traditional Chinese veterinary medicine. Meanwhile, discussion was carried out to shed light on the development of modern Chinese veterinary medicine. Results indicate that innovative tools could strongly promote the evolution of traditional Chinese veterinary medicine and the innovative thinking has important implications for the development of modern Chinese veterinary medicine.

Modern agriculture is generated on the basis of traditional agriculture, and many kinds of wisdom of existence are contained in agricultural heritage and still have important practical significance today. As an important agricultural heritage in China, Binglangjiang buffalo feeding system has modern values of production, ecology, science and culture, and could promote the development of modern agriculture and the rural revitalization in the frontier minority areas. Through summarizing the modern value of Binglangjiang buffalo feeding system, this study can be conducive to the protection and utilization of agricultural heritage and make the heritage play a greater role in the development of agriculture and rural areas in the new era.

This study aims to investigate the differences of biological indexes and meat nutrients of Cyprinus carpio from earth pond reared mode and rice field reared mode (earth pond reared is defined as ER and rice field reared as RR, respectively). Three ER and three RR carps (approximately 800 g) were collected to measure and compare the biological indexes. In addition, the contents of conventional nutrients, amino acids and fatty acids of meat were analyzed and compared between ER and RR. The results showed that the condition factor and meat yield of ER were significantly higher than those of RR, while higher caudal peduncle length/caudal peduncle depth ratio was recorded in RR. Higher contents of crude fat, crude protein, ash, total essential amino acids, total nonessential amino acids, total amino acids and total monounsaturated fatty acids, and the essential amino acid score of meat were detected in ER, while significantly higher contents of total polyunsaturated fatty acids, ∑n-6 PUFA, and total highly unsaturated fatty acids were recorded in RR. In conclusion, the RR has slender body, lower meat yield and lower conventional nutrient contents; the meat amino acids contents of ER are higher than that of RR, while the meat fatty acids composition of carps of the two modes has their own advantages, respectively.

To improve the water quality, the fishery multiplication and the restoration of ecological environment, the application of EM bacteria has attracted extensive attention and become a research hotspot in recent years. This study systematically reviewed the definition and source of EM bacteria, the effect and mechanism of EM bacteria in aquaculture in recent decades, and elaborated the factors affecting the effect of EM bacteria. It is found that: EM bacteria have significant effects on regulating microbial ecological structure, reducing harmful substances in water environment, improving immunity, gaining weight and increasing yield; however, the basic theoretical research of EM bacteria technology is still relatively weak, and there are still deficiencies in the production technology and application process. Therefore, in the future, it is necessary to improve production technology, establish and improve screening system, and develop new fields of research and application of EM bacteria in aquaculture, so as to create greater economic value for aquaculture and provide the possibility for sustainable aquaculture.

To promote the transformation and upgrading of pond aquaculture model in China, and to develop environmental-friendly farming model, this paper summarizes the development of China's freshwater aquaculture industry, sums up the present application demonstration of Intensive Pond Aquaculture(IPA) in China, analyzes the composition and advantage of IPA system, points out the problems and process defects in the application of IPA in aquaculture of different fish species, puts forward the optimization scheme and suggestions. The authors think that IPA is suitable for enterprise management, which can reduce management investment and improve aquaculture efficiency. In the application of IPA, system optimization and process innovation should be carried out according to the biological habits of fishes, in order to adapt to the needs of famous and excellent fish species. Due to the advantages of water saving, ecology, high efficiency and environmental protection, IPA could meet the future development requirements of aquaculture, and has a broad application prospect and development space in China's freshwater aquaculture industry.

In order to explore the way of water spinach planting in floating bed affecting the water micro-ecological environment of tilapia aquaculture ponds, water spinach floating beds were set up in the ponds under the 10% coverage. These ponds served as the treatment group, while the other ponds without floating beds served as the control group. After the vigorous growth of water spinach, the samples of water from treatment ponds, control ponds, and the samples of water spinach roots were collected respectively. The DNA of the samples was extracted, part of them was used to amplify the 16S rRNA genes and carry out the high-throughput sequencing, to investigate the effect of water spinach planting on the bacterial community structure in water, and analyze the relationship between the root system of water spinach and the bacterial community structure of surrounding water. Another part of DNA was used to conduct the fluorescent quantitative PCR to determine the copy number of nitrogenase gene, and analyze the effect of water spinach planting on the nitrogenase genes in tilapia aquaculture pond ecosystems. The results showed that the direct effect of water spinach planting on the community structure of planktonic bacteria in the water was not significant; however, the root biofilm of water spinach played an important role as a key part of the pond micro-environment. At the same time, water spinach root biofilm also increased the number of nitrogen-fixing microorganisms per unit volume in pond water.

The growth characteristics of Pseudorasbora parva cultured artificially were analyzed, in order to provide scientific basis for promoting culture of P. parva. P. parva were cultured artificially in the outdoor flowing water ponds from March 2016 to November 2016. The body weight, body length and total length were measured, respectively. Then the growth characteristics of P. parva were analyzed. The 180 days old fish had average total length of 3.96 cm, average body length of 3.23 cm and average body weight of 0.49 g. The special growth rate, daily weight gain and condition factor were affected by the change of water temperature significantly. The linear relation model between body length（LB）and total length（LT）was described as LT=1.0589LB 0.767,（R2=0.8628）, and the curve relation model between body length（LB） and body weight （W）of the P. parva was expressed as W=0.0466LB2.1623（R2=0.8306）. The coefficient variation was changed from 6% to 14% in body length, from 20% to 41% in body weight and changed from 1.45 to 5.31 in condition factor. P. parva shows strong adaptability under artificial culture condition, thus it indicated that P. parva should be cultured artificially on a large scale.

To investigate the microbial communities’ structure of water and intestine of black sea bream (Acanthopagrus schlegelii) reared in in-pond raceway culture system (IP) and pond (EP), intestines and culture water were selected as research objects. Using high-throughput sequencing technology, the structure and function of bacterial communities under the two different culture modes were compared and analyzed. The results show that the microbial communities are mainly composed of Proteobacteria, Actinobacteria, Cyanobacteria, Firmicutes, Bacteroidetes and Chloroflexi, and the sum of their abundance is 98.32%-99.22%. At genus level, bacteria are significantly different. Furthermore, the main increased species in IP mode were Ruegeria (14.84%) Synechococcus (14.24%), Marivita (3.58%), norank_o__PeM15 (2.97%) and norank_C__KD4-96 (2.56%)(P<0.05) (IP > EP). However, the main bacteria in EP model are Enterobacter (10.31%), Mycobacterium (10.30%), Romboutsia (7.37%), Enterococcus (6.29%) and Lactococcus (5.38%) (P<0.05) (IP < EP). The bacterial community in intestine has high richness and diversity, IP mode is significantly higher than that in EP mode (P<0.05), but there is no significant difference between fish intestines (P>0.05). There are differences in the structure and function of the flora under the two culture modes, and there are a large proportion of bacterial communities with significant differences in relative abundance. Most of the dominant bacteria with significant differences are beneficial bacteria in the intestine of black sea bream in IP mode, while in the EP mode, the bacteria are mostly chronic or conditional pathogens.

Near-infrared spectroscopy is a new method for rapid spectral analysis. With the development of spectroscopy and stoichiometry, near-infrared spectroscopy has been widely used in agriculture, food, medicine and petrochemical industries, which has greatly improved the informatization level of various industries. Based on the application status of near-infrared spectroscopy in poultry breeding, the development of near-infrared spectroscopy and its application in feed ingredient detection and poultry meat detection are summarized in this paper. Within the aspects of feed detection and poultry meat detection, a mathematical model with high precision and high stability for predicting was established by correlating the spectral information of the poultry meat sample with the reference value of the quality index. Compared with traditional methods, near-infrared spectroscopy has the advantages of providing large amount of information and fast calculation. This paper also summarizes the application status of near-infrared spectroscopy in feed quality detection and meat quality detection, and points out the possibility of large-scale application of near-infrared spectroscopy in poultry farming. The problems and future development of near-infrared spectroscopy are discussed; the results show that NIR spectroscopy has good development prospects and application value in feed and animal products’ detection.

In this paper, we optimized the determination method for geosmin (GSM) and 2-mathylisoborneol (2-MIB) in aquaculture water and aquatic products by using the method of microwave distillation - solid-phase microextraction - gas chromatographic-mass spectrometry (MD-SPME-GC-MS). We optimized the four pre-treatment processing parameters, including carrier gas rate, microwave power, distillation time and collection method, and determined the experimental conditions as follows: carrier gas rate of 60 mL/min, microwave power of 400 W, distillation time of 6 min, and constant of 250 mL. In aquaculture water, the detection limit of GSM and 2-MIB reached 1 ng/L and 10 ng/L, respectively. In aquatic products, the detection limit of GSM and 2-MIB reached 0.025 μg/kg and 0.25 μg/kg, respectively. The standard curve of this method had good liner relation in the range of 1-200 ng/L and 10-200 ng/L (R² was 0.9997 and 0.9982, respectively). The average recovery rate of GSM and 2-MIB at different concentrations (1, 5, 7, 10, and 20 μg/kg) was 45.28%-49.92% and 82.15%-87.36%, respectively. In this experiment, the water samples and aquatic product samples from Wuxi were detected by this method. The result showed that the average concentration of GSM and 2-MIB in the water samples was 19.58 ng /L and 58.29 ng /L, respectively. In aquatic products, only GSM was detected, and the average concentration was 0.61 μg/kg. This method can be widely used to detect fishy substances in aquaculture water and aquatic products.

This paper reviews the present situation of aquaculture in Rudong area of Jiangsu Province. The main shrimp and crab culture species in this area were summarized, including Penaeus vannamei, Eriocheir sinensis, white backtail shrimp and comb crab. The current status of shrimp and crab culture in Rudong area was analyzed, so did the related problems of seed stock and diseases in the process of the sustainable development. Countermeasures were put forward, such as strengthening scientific culture management, introducing professional and technical personnel, enhancing scientific and technological services, adhering to ecological water-saving aquaculture mode, developing green shrimp and crab culture industry, building well-known brands, and promoting economic and social benefits.

This paper aims to evaluate the influence of meteorological factors on the shrimp and crab breeding industry in Xiangyang of Hubei Province, and put forward corresponding measures for scientific breeding of shrimp and crab. The laws of meteorological factors' change were analyzed based on nearly 30 years data observed in Xiangyang. The authors reviewed the annual changing trend of main meteorological factors related to the breeding of shrimp and crab, such as temperature, sunshine hours, continuous wet weather, rainstorm, wind force and atmospheric pressure, and discussed the potential climate risks, in order to make rational use of weather forecasting and early warning to achieve the purpose of disaster prevention and reduction. The results showed that suitable temperature, abundant rainfall, mild climate, sufficient sunshine and relatively fewer meteorological disasters could provide favorable climatic conditions for the breeding of shrimp and crab in Xiangyang. By analyzing the law of temperature change in Xiangyang and the relationship between air temperature and water temperature, the authors determined the best period of postlarvae release (after Qingming) and the best period of fishing (before Frost's Descent) for shrimp and crab breeding. At the same time, the authors also analyzed the effects of meteorological factors such as low temperature damage, sunshine hours, continuous rainstorm, gale and thunderstorms on the breeding of shrimp and crab, and put forward the corresponding preventive measures to reduce the impact of weather disasters. This study could provide a theoretical basis for the local meteorological department to make medium and long-term climate prediction and short-term weather forecasting and warning services according to the shrimp and crab breeding cycle. Based on our research results, farmers should attach great importance to the application of early warning information and take active measures to reduce the loss of shrimp and crab breeding caused by meteorological disasters.

Using the acid rain data, meteorological data, soil type data and DEM data of Xuyi County, we selected summer high temperature days, acid rain, soil type, altitude as key factors influencing lobster growth and built the agro-climatic zoning model with analytic hierarchy process method. We adopted ArcGIS 10.0 to divide the climatic suitability zoning of lobster cultivation in Xuyi. The results show that the suitable areas mainly distribute in north Xuyi, and the relatively suitable areas mainly locate in hilly areas in the southeast, and the unsuitable areas locate in the low hilly area in the southwest. The study could provide references for planning layout of lobster farming in Xuyi County.

By adding Chlorella to tilapia aquaculture water, this study aims to explore the optimal concentration of Chlorella for the degradation of N and P and the regulation of microbial community in aquaculture water. Control group (NC), low concentration group (LC), middle concentration group (MC) and high concentration group (HC) were set to explore the effects of different concentrations of Chlorella on reducing the concentration of N and P in tilapia aquaculture water. The 16S rRNA high-throughput sequencing technology was used to analyze bacteria community structure changes of aquaculture water body. Compared with other treatment groups, N and P nutrition of water body in HC group decreased, and the degradation rate of nitrogen in three forms was NH₄⁺-N>NO₃^--N>NO₂^--N. Compared with NC group, the microbial diversity of MC and HC group decreased. The relative abundance of Proteobacteria in each treatment group increased, while that of Bacteroidetes decreased, and the relative abundance of Bacteroidetes in HC group was the highest, the community richness was significantly correlated with the content of NH₄⁺-N. In summary, Chlorella can absorb N and P nutrition from aquaculture water, regulate aquaculture water microbial community structure, and improve aquaculture water quality. The study could provide a theoretical basis for aquaculture production practice.

The present trial was conducted to evaluate the growth performance of three largemouth bass Micropterus salmoides strains based on indoor recirculating aquaculture system. M. salmoides juveniles of the three stains, including ‘Youlu No.1’, ‘Youlu No.3’ and ‘Zhelu No.2’ were assigned randomly into 9 tanks with triplicate tanks for each stain respectively. Each tank had 30 fish (initial body weight 6.08±0.12g) and the feeding trial lasted 8 weeks. The results showed that the survival rate was all above 98.89% (P>0.05); the body weight gain ranked as ‘Youlu No.3’>‘Youlu No.1’>‘Zhelu No.2’ without significant differences (P>0.05); while the lowest variable coefficients of body length and weight were both observed in ‘Zhelu No.2’(P>0.05). The morphological indices among the three strains showed no significant differences (P>0.05). The higher feed coefficient rate and protein efficiency ratio were found in ‘Zhelu No.2’ and ‘Youlu No.3’, respectively (P<0.05). There was no significant difference of dorsal muscle composition and amino acids’ content among the three stains (P>0.05). The activities of trypsin in gut and liver were significantly lower in ‘Zhelu No.2’ than those in other stains (P<0.05). Ten parameters contents in serum maintained stability and no statistic difference existed among the three stains (P>0.05). The data generated from the current trial suggest that M. salmoides is an appropriate fish species for indoor recirculating aquaculture, and ‘Youlu No.3’ shows relative better growth performance in the present system. ‘Zhelu No.2’ also shows very considerable body weight gain, nutrient composition as well as resistance when compared with ‘Youlu’ stains, providing good potential as a breeding population.

In order to study the changes of phytoplankton community in fish-shrimp-shellfish integrated multi-trophic aquaculture seawater ponds and provide a scientific basis for the optimization of culture model and the ecological regulation of aquaculture ponds, sampling and detection were carried out regularly to analyze the phytoplankton community in water and its correlation with nutrient content during the culture period. The results showed that the species number of phytoplankton in the ponds was higher than that in the natural sea areas. The cell density of phytoplankton in the ponds was higher than that in the natural sea areas in the middle and late stage of culture, except that it was slightly lower in the early stage of culture. Skeletonema costatum was the dominant species in the early stage of culture, Scippsiella trochoidea was the absolute dominant species in the middle stage, and Skeletonema costatum, Karenia mikimotoi and Scippsiella trochoidea were the main species in the later stage. The fluctuations of phytoplankton diversity index (H') and evenness index (J) in the ponds were significantly greater than those in the natural sea areas. It showed a trend of succession of phytoplankton community in the ponds from diatoms to dinoflagellates, while diatoms were absolutely dominant in the natural sea areas. There was a significant correlation between the cell density of Karenia mikimotoi and the content of active phosphate.

To study the effect and mechanism of “using aquaculture to curb alkali saline-area” model on the saline-alkali land, the saline-alkali land in Jingtai County was used as test field, the solodization effect of aquaculture technology on sandy saline-alkali soil and loam saline-alkali soil was compared. The effects of aquaculture on saline and alkali migration were studied by regularly monitoring and analyzing the changes of water quality parameters in different types of soil and water before and after fish culture. The results showed that the aquaculture model could improve the soil environment of saline and alkaline areas to some extent, and the control effect on sandy soil was better than that on loam soil. In addition, the ammonia nitrogen produced during the cultivation did not show an upward trend, which indicated that it did not cause secondary pollution to the local area. The results of this study provided theoretical and technical support for the application and promotion of “using aquaculture to curb alkali saline-area” model in northwest China.

To achieve the steady yield of rice and to maximize the nutrient use efficiency during the paddy rice production irrigated by the tail water of ‘Macrobrachium Rosenbergii’ aquiculture completely, four treatments were set up for the pot experiment which contained CK (blank control), BC (biochar), TG (soil improvement solution), BT (biochar and soil improvement solution). The suitable material types were screened by the comparison of nutrient transport status in rice-soil system and the growth indexes of paddy rice in different treatments. The results showed that the addition of BC, TG and BT had positive effects on TN accumulation in topsoil (0-10 cm), TP accumulation in soil （0-25cm）,and system nutrition loss;meanwhile, the former two treatment were also helpful for TN accumulation in soil（0-25cm）,and the system nutrition. TG promoted the NO₃^- accumulation in the topsoil (0-10 cm) (P<0.05). Except BC treatment,TN and TP in paddy rice showed a downward trend at the same time in the existence of materials. In the BT treatment, the chlorophyll content at filling stage was higher than that of TG and CK (P<0.05) apparently, the first internode length of material treatment was lower than that of CK (P<0.05), while the difference of the other treatments was not significant(P>0.05). There was no significant difference between actual yield and theoretical yield of different treatments (P>0.05). To summarize, comparing with other materials, TG holds back NO₃^- as the main nitrogen nutrition effectively, enhances the nutrition utility efficiency of aquiculture wastewater, decreases the leaching risk, controls the internode growth of the rice bottom obviously, reduces the lodging risk and has no inhibition on the growth and yield of rice. Thus, TG is a potential material for the enhancement of nutrient utility efficiency in paddy rice irrigated by the wastewater from ‘Macrobrachium rosenbergii’ aquiculture completely.

The preliminary study showed that the integrated mode for water quality control, named as “5% water spinach (Ipomoea aquatica Forsk.) + 10% filler + algae splashing (Chlorella pyrenoidose)” is worth popularizing. To further verify the effect, the purification effect of different water spinach planting ratios on nitrogen and phosphorus in pond water was studied. Water quality indexes, such as TN (total nitrogen), NH₃-N (ammonia nitrogen), TP (total phosphorus), COD_Mn (permanganate), TSS (total suspended solid), pH and DO (dissolved oxygen), were determined by setting the planting proportion of 5%, 8% and 10% of water spinach, the environmental and economic benefits were also evaluated. The results showed that the TN, NH₃-N, TP, COD_Mn and TSS in tilapia pond were reduced to a certain extent by the cultivation of water spinach. The removal rates of TN and TP were 10%-15% and 20%-40% respectively. The 5% water spinach planting group also had the good removal effect on NH₃-N and COD_Mn, and the economic benefit of this mode was good, which was suitable for application.

To assess the pollution risk and environmental loaded pressure (ELP) caused by the rapid development of livestock and poultry breeding (LPB) during the 14th Five-Year Plan period in the Ningxia Hui Autonomous Region, according to the data of LPB, the emissions of livestock and poultry manure (LP), chemical oxygen demand (COD), nitrogen (N) and phosphorus (P) were estimated by the pollutant discharge coefficient method. Environmental loaded pressure of LPB was evaluated by the indexes, including the suitability evaluation, land-loaded pressure and the nutrient-loaded pressure. The results showed that: (1) the emissions of COD, N and P were 1.23 million, 68600 and 7440 tons, respectively; (2) the suitability areas of LPB were mainly distributed in the southern mountainous area, in total, the land-loaded capacity was greater than the amount of LPB; however, the amount of LPB in Litong District was 3.1 times that of the land-loaded pressure, which posed a great risk of breeding pollution; the manure could not be all returned to field in Yinchuan urban area, Litong District and Jingyuan County; (3) the N emission was estimated to reach 120000 tons in 2025, showing an increase of more than 50000 tons compared with that of 2020; the P emission was estimated to reach 12000 tons, correspondingly 1.7 times that of 2020; the COD emission was estimated to reach 2.517 million tons, correspondingly 1.5 times that of 2020. In 2025, the loaded warning value of cultivated land for LP will reach 3.50. Therefore, countermeasures were put forward from six aspects: proper control of breeding scale, strict LP returning to field, strengthening fertilizer use of LP, scientific treatment of LP pollution, setting up LP centralized treatment center and policy support.

This experiment was conducted to investigate the effect of Lactobacillus plantarum P-8 on the growth performance, fecal pH and content of indole and skatole, lincomycin hydrochloride residue of broilers in the scale breeding. 180000 one-day-old commercial broilers (Arbor Acres, AA) were randomly divided into three groups with 60000 chickens in each group. The chickens in the control group were fed the basal diet, and those in the two test groups (group 1 and group 2) were fed the basal diet and L. plantarum P-8. Lincomycin hydrochloride was added in the basal diet of three groups for 30 days and the addition was 3, 3 and 1.5 g/t for the control group, group 1 and group 2, respectively. The results showed that the survival rate, average weight and water consumption of the two test groups were significantly higher than that of the control group (P<0.05), the feed conversion ratio of the two test groups was significantly lower than that of the control group (P<0.05), there was no significant difference between the two test groups (P>0.05). The fecal pH and the content of indole and skatole in chicken fecal of the two test groups were significantly lower than that of the control group (P<0.05), and there was no significant difference between the two test groups (P>0.05). The lincomycin hydrochloride residue in chicken of the two test groups was significantly lower than that of the control group (P<0.01), and there was no significant difference between the two test groups (P>0.05). In conclusion, L. plantarum P-8 is advantageous in reducing the dosage of antibiotics and improving the growth performance and breeding environment in the scale broiler breeding, and it is of benefit to the sustained and healthy development of poultry breeding, and will have a wide application prospect.

At present, most tail water of aquatic animal culture is discharged into the environment directly, which has caused severe environmental pollution. To control the emission of aquaculture tail water effectively, the following strategies to farmers and policy managers in terms of thoughts and actions are put forward in line with the principle of overall systematicness and practicability: (1) to understand and maintain China’s basic state policy for environmental protection; (2) farmers need to improve their management level and establish new farming models; (3) managers should set up regional and intensive resource utilization and treatment standards of tail water emission, establish and improve relevant laws and insurance systems, and strengthen the governance.

The authors introduced the study of bacterial community structure of biofloc, and set forth the composition and diversity of bacterial community structure at different stages of biofloc formation in the aquaculture system. Then, we analyzed the effect of environmental conditions, including different carbon sources and carbon-nitrogen ratios (C/N), on the compositions and diversities of microbial community in the biofloc as well as in the intestine of cultured animals. Besides, the roles of microbial community of biofloc were summarized, including the function of nitrogen removal and the inhibition of pathogenic bacteria growth and reproduction. Finally, the authors looked forward to the future developments and research directions of biofloc technology. The researchers could try to study the acclimation of the heterotrophic biofloc system into a nitrifying biofloc system gradually by reducing the amount of carbon source added progressively during the middle and late stages of biofloc culture system. In addition, the combination of the biofloc technology and the biofilm technology in aquaculture system could also be demonstrated in the future by the researchers.

In the fermentation bed feeding mode, the growth traits of broiler hen were recorded in 3 batches, after 10 weeks, 40 hens were chosen from every mode for slaughtering, and the slaughter performance and quality analysis are carried out. Results showed that: for growth traits, the weight of 5 and 9 weeks of the first batch in fermentation bed feeding mode was significantly higher than that of flat online mode (P<0.01), the weight of 5, 6 and 9 weeks of the third batch in fermentation bed feeding mode was significantly higher than that of flat online mode (P<0.01); for meat quality, the filtration rate, moisture content and crude protein of chest muscle in flat online mode were significantly inferior to those in fermentation bed mode (P<0.05). The pH value and shear force of leg muscle quality in fermentation bed mode was significantly lower than those in flat online mode (P<0.05). Therefore, the fermentation bed feeding mode is superior to the flat online mode and can achieve zero discharge and clean production, worthy to be recommended to small and medium-sized feeding farms.

With the improvement of living standards, people pay more and more attention to dietary quality； And several carnivorous fishes, such as perch, Channa argus and Siniperca chuatsi have been paid more attention because of their higher nutritive value. At present, these kinds of economic fish are in the transformation process of aquaculture model from the traditional pond culture to the pond engineering culture and from feeding the ice fresh fish to feed the artificial formula feed. This paper summarized the current aquaculture status and the indexes in the specific evaluation of nutritional value for these major freshwater aquatic products, and summarized the possible changes of nutritional value in the course of the conversion of the aquaculture model. After the discussion, it was found that the nutritional value, especially protein quality of economic fish such as perch and mandarin fish fed with formula feed were lower than those fed with ice fresh fish ，and the effect of this new aquaculture model with pond circulating water culture on the nutritive value of these carnivorous fishes was unclear for the nutritional value of the fish.However, seen from the present research, pond circulating water culture can effectively improve water quality and limit the accumulation of harmful substances to a certain extent. So this new aquaculture model has a positive effect on the edible quality of these kinds of economic fishes. This paper summarizes the mechanism of nutrient value formation during the transformation of aquaculture model for the main freshwater aquatic products, to provide a theoretical basis for the implementation of a new green and healthy sustainable aquaculture model.

Based on InCites database, this paper systematically analyzed the development of veterinary sciences of China Agricultural University, Huazhong Agricultural University, South China Agricultural University, and Yangzhou University during the period of 2008 to 2018. Moreover, the discipline competitiveness was evaluated by comparing with that of the University of California Davis, University of London Royal Veterinary College, and Ghent University. The results show that veterinary sciences of the four Chinese universities have developed well in recent years, with increased output of academic papers. However, there is still a big gap between domestic and foreign universities in terms of the quantity of papers, citation frequency, cites per document, highly cited papers, and H- index. Therefore, it is suggested that domesticniversities should strengthen academic team building and pay more attention to talent cultivation and introduction to increase the output of academic papers, promote the connotative development of veterinary sciences to improve the quality of papers, and strengthen international exchanges and cooperation to enhance the academic influence and innovation ability.

To verify the practical culturing effect of a previously designed circulating water treatment system based on heterotopic pond restoration technology, a large-scale multi-species saturating culture experiment was carried out for 3 years. The effects of the system on water quality control was evaluated by measuring the total nitrogen (TN), total phosphorus (TP), chemical oxygen consumption (COD_Mn) and chlorophyll (Chla) in a common freshwater fish culturing pond. The results showed that in the early stage of the experiment, the total nitrogen level (TP) of the circulating water of the pond reached Class III of the Environmental Quality Standards for Surface Water (GB 3838—2002), and the total phosphorus level (TN) reached Class III to V. The average removal rate of TP, TN, COD_Mn and Chla was 40.13%, 45.02%, 43.37% and 86.6%, respectively. The removal efficiency of the system was significant. In the late stage of the experiment, with the continuous increase of the feed input, although the efficiency of the circulating system was greatly improved, the data of each index were still higher than expected. This experiment provides a new idea for the treatment of large-scale aquaculture water by circulating water in freshwater ponds.