Effects of magnesium on the performance of sows and their piglets

The objective of this study was to evaluate the effects of supplemental magnesium (Mg) on the performance of gilts and parity 3 sows and their piglets. Fifty-six gilts (Trial 1) and 56 sows (Trial 2) were assigned to one of 4 treatments according to their mating weight, respectively. The treatments comprised corn-soybean meal based gestation and lactation diets (0.21% magnesium) supplemented with 0, 0.015, 0.03, or 0.045% Mg from mating until weaning. The results showed that magnesium supplementation significantly (P < 0.05) reduced the weaning to estrus interval in both gilts and sows. There were significant effects (P < 0.05) of supplemental magnesium on the total number of piglets born, born alive and weaned in sows. In late gestation and lactation, the digestibility of crude fiber (quadratic effects, P < 0.05), and crude protein (P < 0.05), were significantly influenced by magnesium in gilts and sows, respectively. There were differences among the 4 groups in terms of the apparent digestibility of dry matter and crude fiber in sows (P < 0.05) during both early and late gestation. The apparent digestibility of gross energy was increased for sows in late gestation (P < 0.05), and lactation (quadratic effects, P < 0.05). At farrowing and weaning, serum prolactin levels and alkaline phosphate activities linearly increased in sows as the Mg supplementation increased (P < 0.05). Serum Mg of sows at farrowing and serum urea nitrogen of sows at weaning was significantly influenced by Mg supplementation (P < 0.05). The Mg concentration in sow colostrum and the serum of their piglets were increased by supplemental magnesium (P < 0.05). In addition, growth hormone levels were linearly elevated (P < 0.05) in the serum of piglets suckling sows. Our data demonstrated that supplemental magnesium has the potential to improve the reproduction performance of sows, and the suitable supplemental dose ranged from 0.015% to 0.03%.     

培养基质,赤霉素和硼对蕨菜孢子萌发成苗影响的研究

为了提高蕨菜孢子人工培养成苗效率,对４ 种培养基质和赤霉素（ＧＡ３）、硼３ 种使用水平的孢子萌发成苗效果进行了研究。结果表明,森林土、琼脂和蛭石间原叶体数无差异,但成苗率间差异显著;森林土成苗率最高,达到４２．８６％ ;砂基上孢子虽能萌发产生片状体,但不能发育到性器官形成期;赤霉素对孢子萌发生长具有显著的促进作用,在含有０．１５×１０－ ７ ｇ／Ｌ赤霉素培养基上成苗率较高;硼可提高配子体受精成苗,并以０．０５％ 硼酸处理效果最好;赤霉素与硼有显著的互作效应,含有０．１５×１０－ ７ ｇ／Ｌ赤霉素培养基上生长的原叶体,在性器官形成期喷施０．０５％ 硼酸,成苗率高达５１．６０％ 。     

屠宰环节检疫检验印章印油使用现状及问题分析

本文调研并整理了屠宰环节现行有效的检疫检验印章种类及印油的使用情况,分析了实际应用中存在的问题和潜在风险,并就进一步规范屠宰环节检疫检验印章及印油的使用和管理提出了建议。     

一例牙鲆淋巴囊肿病例的诊断及病毒MCP基因遗传进化分析

2019年1月,山东省某牙鲆鱼场出现疑似淋巴囊肿病例。患病鱼体表长有灰白色菜花样瘤状物,死亡率超过30%,给养殖场造成了较为严重的经济损失。为确定发病原因,对该鱼场病死鱼进行了病理组织学诊断和病毒检测,并对病毒MCP基因进行了序列测定及遗传变异分析。结果显示：眼观及组织学病变符合淋巴囊肿病的病变特征;所检测到的病毒与选定的参考毒株核苷酸和氨基酸同源性分别为78.7%~99.9%和86.8%~100%。MCP基因遗传进化分析显示,检测到的病毒与LCDV-C、JF00Kuma、JF03Yoshi、JF03GunNeA、JF、LCDV-K1等毒株同属于淋巴囊肿病毒基因II型,且与我国分离株LCDV-C有较高的同源性。经综合诊断,确定该流行病由淋巴囊肿病毒基因II型所致。该研究为该病的综合诊断及流行病学调查提供了新资料,为下一步进行该病毒相关分子生物学研究以及疫苗制备等提供了理论依据。     

Effects of Exogenous Glycine Betaine on the Physiological Characteristics in Medicago sativa Seedlings under Low-temperature Stress北大核心CSCD

In this study,the 'Ganong 5th' alfalfa (Medicago sativa L.) was used as experimental material,and two application methods (leaf application,root application) and six exogenous betaine concentrations (0,10,20,30,40 and 50 mmol·L-1) were used to treat the seedlings of alfalfa. Plant growth and related physiological indexes were measured after 7 days of low temperature (4?) stress,and the physiological mechanism of exogenous betaine to alleviate the low temperature stress of alfalfa was explored. The results showed that exogenous GB alleviated the loss of plant height,root length,leaf dry weight,root dry weight and chlorophyll content,and increase the content of soluble sugar (SS) and free proline (Pro),and reduced the increase in leaf relative membrane permeability and MDA content. Exogenous GB increased antioxidant enzyme activities and non-enzymatic antioxidant content. And also,exogenous GB enhanced the osmotic adjustment capacity of the plant by increasing endogenous GB accumulation and BADH activity. These results indicated that exogenous GB enhanced the resistance of Medicago sativa to low-temperature stress under low temperature adjustment. The membership function analysis indicated that spraying 30 mmol·L-1 GB on the leaves and spraying 40 mmol·L-1 GB on the roots had the best effect on alleviating the low-temperature stress of alfalfa seedlings. © 2019 Ｊｏｕｒｎａｌ ｏｆ Ｒｅｆｒｉｇｅｒａｔｉｏｎ. All rights reserved.     

发展畜牧产业 推进现代农业

现代农业的内涵相当丰富,包括农林牧副渔等诸方面。就畜牧业而言其位置和作用在现代农业中占有重要地位,畜牧业的持续健康发展是现代农业的重要内容,忽视或离开了畜牧业的发展,现代农业就无从谈起。所以建设现代农业,必须把发展畜牧业放在重要位置,作为重要内容去抓。     

对分割肉检疫监管的探讨

公众对肉类产品的需求逐渐由白条肉向品牌化、精细化的分割肉方向发展,相关产品的检验、检疫、监管已成为社会关注的热点。本文对三种不同类型肉品分割行为进行了分析,探讨检疫监管存在的问题,并提出明确监管主体、修订相关法律法规、建立追溯平台、强化主体责任的建议,供同仁参考。     

航天诱变混菌固态发酵玉米秸秆生产单细胞蛋白条件的优化

通过正交试验对啤酒酵母YB-6的接种时间、接种量和黑曲霉ZM-8与啤酒酵母YB-6共生发酵时间等因素的参数进行了优化。结果表明,啤酒酵母YB-6的接种时间(A)、接种量(B)和共生发酵时间(C)对CMC酶、FPU酶和SCP含量的影响大小顺序均为ACB,且产CMC酶和SCP的最优组合为A3C2B2,即酵母菌的接种时间为黑曲霉ZM-8发酵24h后、共生发酵时间为48h、接种量为10%;产FPU酶的最优组合为A4C3B3,即酵母菌的接种时间为黑曲霉ZM-8发酵36h后、共生发酵时间为60h、接种量为15%。最后,综合各因素将发酵条件的最优组合确定为A3C2B2。优化后的FPU酶、CMC酶和SCP含量分别为6.83、28.12U/g和26.73%,比优化前测定各指标值均有不同程度的提高。     

犬常见皮肤病的日常诊护

犬皮肤病是犬临床诊治中常见病之一。犬因品种、年龄、个体、营养、生活环境等不同而引起的皮肤病有很大的差异。本文就几种常见的犬皮肤病的不同的临床症状进行了简要综述,旨在给饲养者提供一些早期的、简单的鉴别及诊断,能尽快做出相应的预防和护理措施,并及时就诊。