基于改进YOLO v4的生猪耳根温度热红外视频检测方法

基于热红外视频的生猪体温检测过程中,视频中保育期生猪头部姿态变化大,且耳根区域小,导致头部和耳根区域定位精度低,影响生猪耳根温度的精准检测。针对以上问题,本文提出了一种基于改进YOLO v4(Mish Dense YOLO v4,MD-YOLO v4)的生猪耳根温度检测方法,构建了生猪关键部位检测模型。首先,在CSPDarknet-53主干网络中,添加密集连接块,以优化特征转移和重用,并将空间金字塔池化(Spatial pyramid pooling, SPP)模块集成到主干网络,进一步增加主干网络感受野;其次,在颈部引入改进的路径聚合网络(Path aggregation network, PANet),缩短多尺度特征金字塔图的高、低融合路径;最后,网络的主干和颈部使用Mish激活函数,进一步提升该方法的检测精度。试验结果表明,该模型对生猪关键部位检测的mAP为95.71%,分别比YOLO v5和YOLO v4高5.39个百分点和6.43个百分点,检测速度为60.21 f/s,可满足实时检测的需求;本文方法对热红外视频中生猪左、右耳根温度提取的平均绝对误差分别为0.26℃和0.21℃...     

基于改进YOLO v7的轻量化樱桃番茄成熟度检测方法

为在自然环境下自动准确地检测樱桃番茄果实的成熟度,实现樱桃番茄果实自动化采摘,根据成熟期樱桃番茄果实表型特征的变化以及国家标准GH/T 1193—2021制定了5级樱桃番茄果实成熟度级别(绿熟期、转色期、初熟期、中熟期和完熟期),并针对樱桃番茄相邻成熟度特征差异不明显以及果实之间相互遮挡问题,提出一种改进的轻量化YOLO v7模型的樱桃番茄果实成熟度检测方法。该方法将MobileNetV3引入YOLO v7模型中作为骨干特征提取网络,以减少网络的参数量,同时在特征融合网络中加入全局注意力机制(Global attention mechanism, GAM)模块以提高网络的特征表达能力。试验结果表明,改进的YOLO v7模型在测试集下的精确率、召回率和平均精度均值分别为98.6%、98.1%和98.2%,单幅图像平均检测时间为82 ms,模型内存占用量为66.5 MB。对比Faster R-CNN、YOLO v3、YOLO v5s和YOLO v7模型,平均精度均值分别提升18.7、0.2、0.3、0.1个百分点,模型内存占用量也最少。研究表明改进的YOLO v7模型能够为樱桃番茄果实的自...     

低数据集下基于ASPP-YOLO v5的苋菜识别方法研究

针对田间苋菜识别存在准确率低、样本数量少等问题,通过引入扩展感受野和提取上下文信息的ASPP注意力机制改进YOLO v5苋菜识别模型,在低数据集下改进后的模型能够显著提高F1值和mAP。实验结果表明,在低数据集下引入ASPP注意力机制后苋菜识别模型F1值提高13个百分点、mAP提高18.6个百分点。采用横向录制的方式苋菜被检测到的概率提高15.4个百分点。因此,本研究为苋菜或其他杂草在低数据集下的识别提供了有效的方法,为农业领域的杂草识别和管理研究提供了参考。     

基于改进YOLO v7的生猪群体体温热红外自动检测方法

针对当前生猪规模化养殖过程中基于热红外技术的生猪体温测量效率低的问题,提出了一种基于改进YOLO v7的生猪群体体温检测方法。改进YOLO v7算法在Head层引入VoV-GSCSP结构,降低网络结构复杂度;使用内容感知特征重组(Content-aware reassembly of features,CARAFE)替换模型原始上采样算子,提高特征图放大后的品质,强化生猪头部区域有效特征;引入感受野增强模块（Receptive field enhancement module,RFE）,增强特征金字塔对生猪头部特征的提取能力。本文改进YOLO v7算法对于生猪头部的检测精确率为87.9%,召回率为92.5%,平均精度均值（Mean average precision,mAP）为94.7%。与原始YOLO v7相比,精确率提高3.6个百分点,召回率提高7.0个百分点,mAP提高3.6个百分点。该方法首先自动检测生猪头部区域,再利用头部最大温度与耳根温度的高相关性,最终自动获取生猪体温。温度提取平均绝对误差仅为0.16℃,检测速度为222f/s,实现了生猪群体体温的实时精准检测。综合上述试验结果表明,该方法能够自动定位生猪群体的头部区域,满足生猪群体体温测定的高效和高精度要求,为群养生猪体温自动检测提供了有效的技术支撑。     

池塘培育草鱼种关键技术

1999年6月9月，使用池塘3口（面积1．21hm^2)培育草鱼种。经87d，总产10571kg,其中草鱼种6249kg，出塘率92．5％，饵料系数1．57；鲢、鳙鱼种4322kg，出塘率71．3％。总产值7．35万元，利润4．15万元。同时对草鱼夏花至秋片不同生长阶段蛋白质需求量，以及颗粒饲料粒径与鱼口裂大小关系等进行了试验。     

Relationship between rate of infection and markers of inflammation/immunity in Holy Birman cats with feline coronavirus

The aim of this study was to assess whether Holy Birman cats (HB) have a peculiar immune profile and a higher rate of infection by feline coronaviruses (FCoV). Leucocyte and lymphocyte subsets, antibody titers, α₁-acid glycoprotein (AGP), globulin fractions, IL-4, IL-12 and IFN-γ in blood and fecal FCoV excretion were determined in HB (n = 75) and in cats from other breeds (n = 94). Significantly higher CD4/CD8 ratio, IFN-γ concentration and IL12/IL4 ratio and significantly lower IL-4 concentration and proportion of shedders were found in HB than in other breeds. No other differences were found. In conclusion, this study did not provide evidence of peculiar immune profiles in HB, except for a prevalent Th1 profile, that may explain why in our caseload the rate of shedders was lower in HB than in other breeds.     

Functional characteristics of porcine peripheral T cells stimulated with IL-2 or IL-2 and PMA

In human or mouse, mature T cells express either CD4 or CD8, resulting in different functions in the periphery. Interestingly, porcine CD4 and CD8 double positive (DP) T cells are present in the blood, and their proportions change from youth to adulthood. However, the features of these cells in swine are poorly understood. We investigated the fate of porcine peripheral T cells based on their functional characteristics, including proliferation and the expression of CD4 and CD8 co-receptors. The results showed that all the populations changed their CD8 expression in a time-dependent manner and porcine T cells had different proliferative pattern from human T cells. The results further revealed that Th2 cytokines were increased later in porcine T cells compared to human T cells upon stimulation with IL-2 + PMA. Collectively, we found that the fate of porcine peripheral T cells is different from that of human T cells, and the changes occur in a time- and stimulation-dependent manner.     

种植密度对洛薯8号生物学性状及产量的影响

以洛薯8号为材料,采取随机区组设计,进行相同施肥管理水平下的密度试验,探索洛薯8号获得最好经济效益的栽培密度.结果表明:群体随密度增加而增大,但个体转弱,导致营养生长与生殖生长不协调,植株的抗病性、抗逆性变差;随着密度加大(45 000～90 000株/hm2),单株结薯个数由4.8个减少到3.6个,单株结薯质量由684.71 g减小到410.41 g,平均薯块质量由142.64 g减小到114.00 g,大薯率由75.26％减小到38.92％,商品率逐渐变差,由90.64％下降到63.54％;产量随着栽培密度的增加呈现先增加后减少趋势,栽植密度为45 000株/hm2时产量最低,为30 811.80 kg/hm2,密度为67 500株/hm2时产量达到峰值,为38 426.10 kg/hm2,随后产量逐渐降低.密度67 500株/hm2与密度为60 000、75 000、82 500株/hm2之间产量差异不显著,而与其他密度(45 000、52 500、90 000株/hm2)处理间存在显著差异.从而得出洛薯8号在河南两季作区的适宜栽植密度为60 000～82 500株/hm2,最适宜密度为67 500株/hm2.     

Artificial induction of maturation and fertilization in the Japanese eel, Anguilla japonica

Repeated injections of salmon pituitary extract (20 mg per fish per week) induced vitellogenesis in feminized, cultivated Japanese eels (Anguilla japonica). Oocytes were attained at the migratory nucleus stage after 11 or 12 injections. Addition of 17,20-dihydroxy-4-pregnen-3-one (DHP) into the incubation medium induced germinal vesicle breakdown (GVBD) in the oocytes at the migratory nucleus stage. An injection of DHP (2 µg g^-1 BW), given 24h after an injection of salmon pituitary extract (20 mg fish^-1), succeeded in inducing maturation and ovulation in females which contained occytes at the migratory nucleus stage. Most fish ovulated 15–18h following the DHP injection. Eggs that were ovulated within 15h after the DHP injection showed high fertility and hatchability, but eggs ovulated 18 or 21h after the DHP injection, showed considerably lower fertility and hatchability. A delay between ovulation and stripping of the eggs rapidly decreased both the fertility and hatchability within 6–9h after ovulation, indicating that artificial fertilization must be carried out immediately after ovulation. Repeated injections of human chorionic gonadotropin (hCG) at a concentration of 1 IU g^-1 BW week^-1 induced spermatogenesis, spermiation, and the acquisition of potential for sperm motility in cultivated males. Most males spermiated after the fifth or sixth injection of hCG, and the milt weight gradually increased and remained constant (1–2 g) from the 11th to 31th injection. Sperm motility peaked 24h after each weekly injection, and decreased from the 3^rd day after the injection. Potassium ions are an essential constituent for the maintenance of motility in the eel spermatozoa. Artificial seminal plasma containing 15.2 mM KCl is applicable as a milt diluent. Using these techniques developed for female and male eels, we have succeeded in obtaining many fertilized eggs from cultivated eels.     

Advances in Gene Structure,Evolution and =unction of Plac8

胎盘特异蛋白8（Placenta special gene 8, PLAC8）又称 onzin或 C15,是一种富含半胱氨酸的蛋白。 Plac8广泛分布于真核生物中,其功能也得到越来越广泛的研究,发现其不仅可以调控细胞的分裂,分化和凋亡,还在机体免疫过程中发挥重要作用。本文旨在对 plac8的基因结构特点、进化、表达和功能等方面的最新研究进展及其可能的作用机制进行概述。