猪大脑皮层缘回和外缘回与皮层及皮层下结构的联系──HRP法研究

本文用ＨＲＰ（辣根过氧化物酶）法研究了６只仔猪大脑皮层缘回和外缘回与皮层及皮层下结构的联系，结果如下：（１）将ＨＲＰ注入缘回后，在双侧大脑半球缘回、外缘回和外薛氏回及同侧大脑半球冠状回、扣带回和梨状叶、同侧丘脑的外侧膝状体、枕核、后外侧核、后核群、板内核和室旁核、脑干的蓝斑、中缝背核和中脑中央灰质内均出现标记细胞末梢；在丘脑网状核、脑干网状给构、脑桥核、上丘、顶盖前区、壳核和尾状核中出现标记末梢。（２）将ＨＲＰ注入外缘回后，在双侧大脑半球外缘回、缘回和外薛氏回及同侧压部回、同侧丘脑的外侧膝状体、枕核、后核群、后外侧核、腹后核、板内核和室旁核、脑干的蓝斑、中缝背核和中脑中央灰质内均出现标记细胞和末梢；在脑干网状结构和脑桥核出现标记末梢。     

强啡肽A_（1－13）免疫反应神经元在鸡脑的定位──ABC法研究

取健康成鸡（星杂２８８）１０只，经秋水仙素处理，灌流固定后取脑，作冰冻连续切片，ＡＢＣ法显示，鸡脑强啡肽Ａ１－１３（ＤｙｎＡ１－１３）免疫反应神经元分布于端脑的上纹状体、新纹状体、旧纹状体、外纹状体、海马、旁嗅区和伏隔核；间脑的下丘脑外侧核、丘脑背内侧核后部、丘脑背外侧核后部、室旁核和视前大细胞核等；中脑和延髓的视峡核、中脑外侧核背侧部、峡核、视叶脑室室周灰质、螺旋外侧核、被盖背外侧核、三叉神经中脑核、动眼神经核、中脑中央灰质、前庭核和延髓背侧网状核等。在侧脑室、第三脑室、中脑导水管和视叶脑室的室管膜上有阳性细胞和纤维分布，与脑脊液接触。结果表明，鸡脑ＤｙｎＡ１－１３阳性神经元分布十分广泛，提示ＤｙｎＡ１－１３可通过侧脑室、第三脑室、中脑导水管和视叶脑室释放入脑脊液。     

鸡上纹状体的纤维联系——HRP法研究

将HRP溶液注入鸡上纹状体,追踪投射至上纹状体的纤维来源,在丘脑背外侧前核、背外侧后核,丘脑背内侧前核、背内侧后核,中脑深核外侧部和腹侧部及顶盖背核出现标记细胞。外侧前脑束和隔中脑束出现标记纤维。结果表示.上述核团有纤维投射到上纹状体,且投射均限于同侧。     

应用乙酰胆碱脂酶组织化学技术对鸡胚脑内微血管的观察

应用乙酰胆碱脂酶（ＡＣｈＥ）组织化学技术，研究了２８枚不同胚龄鸡脑内含ＡＣｈＥ阳性反应产物的微血管的分布。结果显示：在孵化第１８ｄ时，脑内已经出现了含ＡＣｈＥ阳性反应产物的微血管。ＡＣｈＥ阳性微血管主要分布在端脑的腹侧纹状体、内侧隔核、前连合核背侧区；间脑的视前区、丘脑前背外侧区、丘脑前背内侧区、丘脑背外侧区、缰核区、间脑中缝区域；中脑深核腹侧部、中脑背外侧核、中脑视叶脑室周腹内侧深层，中脑中缝区域。阳性微血管的管径均小于２０μｍ。结果提示：至少在孵化第１８ｄ时，鸡胚脑内乙酰胆碱已开始发挥其调节脑血流的作用。     

猪中脑网状结构向脊髓颈、腰膨大投射的HRP法研究

以33％的HRP(辣根过氧化物酶)注射于11头幼猪脊髓颈、腰膨大一侧灰质,联大茴香胺绿色反应呈色,逆行追踪了中脑网状结构向脊髓投射的起源部位,证明其起源部位为中脑楔形核,发出同侧投射纤维,达脊髓颈膨大。     

强啡肽A1—13免疫反应神经元在鸡脑的定位：ABC法研究

取健康成鸡（星杂２８８）１０只，经秋水仙素处理，灌流固定后取脑，作冰冻连续切片，ＡＢＣ法显示，鸡脑强啡肽Ａ１－１３（ＤｙｎＡ１－１３）免疫反应神经元分布于端脑的上纹状体，新纹状体、旧纹状体、外纹状体、海马、旁嗅区和伏隔核；间脑的下丘脑外侧核、丘脑背内侧核后部、丘脑背外侧核后部，室旁核和视前大细胞核等；中脑和延髓的视峡核，中脑外侧核背侧部、峡核、视叶脑室室周灰质、螺旋外侧核、被盖背外侧核、三叉神经中     

北京鸭下行投射到脊髓的神经元在脑内的分布——用HRP逆行追踪法研究

用HRP法,逆行追踪了54例北京鸭下行投射到脊髓的神经纤维的起始部位。用乌拉坦麻醉,分别在脊髓的C_7、颈膨大或腰膨大部注射30～50％HRP,灌流固定,取脑做冰冻连续切片。蓝色反应显色,中性红复染,镜检。实验结果,各脑区出现的标记细胞主要位于同侧,对侧较少。而红核内的标记细胞绝大多数分布于对侧,同侧极少。在其它部位,同侧前庭外侧核中,标记细胞较多,双侧的前庭内侧核和对侧的前庭降核中标记细胞极少。对侧小脑内侧核中有较多的标记细胞,对侧小脑皮质的蒲金野细胞层也有少量标记细胞。脑桥和延髓的外侧网状核、巨细胞网状核及延髓中央核均有标记细胞。中缝核有大量标记细胞。另外,下丘脑室旁核及其腹侧和腹外侧的内细胞层和外细胞层,也有标记。在迷走背核、疑核、孤束核、蓝斑及蓝斑下核都有直接到脊髓的投射。在大脑各部和中脑顶盖内未见到标记细胞。本文结合哺乳类和某些禽类的资料与北京鸭的下行传导通路的起源进行了比较。结果表明:北京鸭具有与哺乳类相似的红核脊髓束、前庭脊髓束、网状脊髓束、小脑脊髓束、中缝脊髓束及孤束核脊髓束,而没有大脑皮质脊髓束和顶盖脊髓束。本文中的发现,迷走背核、疑核和小脑皮质向脊髓的直接投射,尚未见过报道。     

鸡中脑中央灰质的光、电镜结构研究

采用尼氏小体染色、髓鞘染色、高尔基技术和透射电镜观察等多种方法,对30只成龄母鸡的中脑中央灰质结构进行了较详细的研究。结果表明:鸡的中脑中央灰质仅位于三角形导水管的两侧,由形状、大小及染色深度不一的小神经元按非均一分布方式组成。神经元可分为卵圆形、梭形、三角形及四边形四种类型。从中脑导水管壁向外侧推移,中脑中央灰质神经元的密度、大小、染色深度、神经纤维的直径和有髓化程度均逐渐增加,无内、外侧亚核的区分。神经元胞体的核质比值很高,神经网主要由无髓神经纤维和树突组成。有轴—树、轴—轴、树—树和轴—体四种突触类型。突触小泡包括清亮圆形小泡、扁平小泡及腰粒性小泡三种。同时还发现有突触小球、轴—轴—树、树—轴—树、轴—树—轴等突触串及神经元胞体间的直接连接。     

禽类下丘脑室旁核向脊髓的直接投射

用微电泳和微量进样技术将ＨＲＰ引入麻鸭、鹅、鸡、鸽子和鹌鹑脊髓的颈中部、颈膨大和腰膨大一侧灰质中，冰冻切片，ＢＤＨＣ法显色，中性红复染。结果，５种动物下丘脑的双侧室旁核内均发现大量标记细胞；同侧标记细胞数多于对侧；标记细胞密集于第３脑室两侧壁的背外侧，形态多为圆形或椭圆形，胞体直径为２０～３５μｍ。本研究结果表明，禽类下丘脑的室旁核可向脊髓发出直接投射，这一直接传导通路呈双侧性投射，但以向同侧脊髓投射占优势，该通路投射的范围广泛分布于脊髓的颈、胸、腰段。     

禽类中脑脊髓束的细胞构筑--HRP和SABC法研究

采用HRP和免疫组织化学SABC结合法，在脊髓的颈中部、颈膨大部和腰膨大部单侧引入HRP，逆行追踪了北京鸭、麻鸭、鸽子和鹌鹑，对中脑至脊髓传导通路的起始部位和细胞构筑进行了研究。脑干冰冻切片，DAB显色。结果发现大量标记细胞分布在中脑对侧的红核、双侧的Cajal中介核、中央灰质和Ew核内。此外，还发现一些标记细胞分布在中脑中缝核和双侧的中脑网状结构。而在顶盖内，没有任何部位出现标记细胞。结果表明：禽类除具有红核脊髓束外，还存在着Cajal中介核至脊髓的直接传导通路，EW核至脊髓的直接传导通路以及中缝核和网状结构至脊髓的直接传导通路，而不存在与哺乳类相似的顶盖脊髓通路。SABC法研究结果表明：中脑的红核脊髓束和中缝核脊髓束的起始神经元是5-羟色胺(5-HT)能神经元。部分网状眷髓柬的起始神经元也是5-HT能神经元。     

Fish meal vs. corn gluten meal as a protein source for dry cat food.

To compare the effects of two dietary protein sources, fish meal (FM) and corn gluten meal (CGM), fecal moisture content, nitrogen balance and urinary excretion were examined in adult cats. The dietary protein source did not cause a significant difference in daily food intake, water intake, urine volume, dry matter digestibility or urinary nitrogen excretion, but fecal moisture content was lower (P<0.02) in the CGM group. The HCl-insoluble fraction of urinary sediment tended to be higher in the CGM group (P<0.10), although urinary pH was similar in the two groups. These results suggest that CGM is comparable with FM in respect to nutritional value and the urine acidifying effect, but FM may be preferable to CGM for the prevention of constipation and struvite urolithiasis in cats.     

Hydrolyzed feather meal as a protein source for growing calves

Growth, digestion and in situ studies were conducted to determine the protein value of hydrolyzed feather meal (Fth) for growing ruminants. Dacron bags containing blood meal (BM), Fth, corn gluten meal (CGM) and soybean meal (SBM) were suspended in the rumen of two steers for 12 h to estimate escape protein. The escape protein value for Fth, 69.1%, was less than that for BM (82.8%) and CGM (80.4%; P less than .05) but greater than that for SBM (26.6%; P less than .05). Apparent protein digestion by lambs was similar (P greater than .10) for isonitrogenous diets containing urea (U), BM, Fth, CGM and SBM. Amino acid contents of the protein sources before vs after a 12-h ruminal in situ digestion were similar (P greater than .10). In a growth study, a basal diet of 80% ensiled corncobs and 20% alfalfa was fed to 60 individually fed crossbred steers (215 kg BW). Steers were supplemented with U, BM, Fth, 1/2 BM:1/2 Fth, 1/2 BM:1/2 CGM and 1/3 BM:1/3 Fth:1/3 CGM (protein basis). Protein sources were fed at 30, 45 and 60% of the supplemental N with urea supplying the remainder. Protein efficiency was calculated using the slope ratio technique. Protein efficiency was similar (P greater than .10) for BM- and Fth-supplemented calves. Protein efficiencies were similar (P greater than .10) for BM:CGM, BM:Fth and BM:Fth:CGM combinations. These data indicate the Fth is a digestible high escape protein source that is useful in diets for growing ruminants.     

Limiting order of amino acids and the effects of phytase on protein quality in corn gluten meal fed to young chicks

An amino acid deletion assay, a protein efficiency ratio (PER) assay, and a slope-ratio growth assay were used to establish the limiting order of AA, and to determine the effects of microbial phytase on protein utilization in corn gluten meal (CGM) fed to chicks during the period of 8 to 21 d posthatching. In Assay 1, a 12% CP CGM diet was fortified with AA to fulfill the digestible AA ideal profile (only Phe + Tyr, Leu, and Pro exceeded requirements) for young chicks. Amino acids were then individually deleted, and all diets were fortified to 23% CP, with Glu varying as necessary. A Met-fortified 23% CP corn-soybean meal diet served as a positive control. No weight gain or feed efficiency differences were observed between the fully fortified CGM basal diet and the corn-soybean meal positive-control diet. The limiting order of AA established in CGM was 1) Lys, 2) Trp, 3) Arg, 4) Thr, 5) Val, 6) Ile, 7) His, 8) cystine, and 9) Met. In Assay 2, diets with 10% CP furnished by CGM or casein were fed in the presence and absence of 1,200 U/kg phytase. A protein source x phytase interaction (P < 0.05) was observed for weight gain, gain:feed, and PER, indicating positive responses to phytase when casein was fed but negative responses to phytase when CGM was fed. In Assay 3, graded levels of protein (8, 16, and 24% CP) furnished by CGM were fed in the presence and absence of 1,200 U/kg phytase. Weight gain and gain:feed increased linearly (P < 0.05) as a function of protein intake, but phytase supplementation had no effect on weight gain or gain:feed slopes. These results indicate that 1,200 U/kg phytase did not increase either CP or AA utilization in CGM for young chicks.     

Evaluation of meat meal, chicken meal, and corn gluten meal as dietary sources of protein in dry cat food

The nutritional value of meat meal (MM), chicken meal (CM), and corn gluten meal (CGM) as dietary sources of protein in dry food formulated for adult cats was evaluated. Twelve healthy adult cats (11 males and 1 female) were used. Dry diets containing MM, CM, or CGM as the main protein source were given for a 3-week period in a 3 x 3 Latin-square design. Digestion and balance experiments were conducted during the last 7 d of each period. In addition, freshly voided urine was taken to determine urinary pH and number of struvite crystals. As compared with the CM diet, dry-matter digestibility was higher and lower for the MM and CGM groups, respectively. Percentages of nitrogen (N) absorption and N retention to N intake were higher in the MM group, and N utilization was not different between the CM group and the CGM group. All cats excreted alkaline urine (pH > 7). Urinary pH, struvite activity product, and number of struvite crystals in urine were lower for the CGM group. There was no difference in retention of calcium and magnesium among the groups. From the point of view of digestibility and N utilization, MM is superior to CGM, and CM is better than or equivalent to CGM as a protein source of dry foods for adult cats. However, when CM is used as a dietary protein source, some manipulation of dietary base excess may be needed to control urinary acid-base balance, because CM contains higher calcium and phosphorus.     

Comparison of corn gluten meal and meat meal as a protein source in dry foods formulated for cats

OBJECTIVE: To compare the nutritional value of corn gluten meal (CGM) and meat meal (MM) as a dietary source of protein in dry food formulated for adult cats. ANIMALS: 8 healthy adult cats (4 males and 4 females). PROCEDURE: Diets containing CGM or MM as the main protein source were each fed for a 3-week period in a crossover study. Digestibility and nutritional balance experiments were conducted during the last 7 days of each period. Furthermore, freshly voided urine was obtained to measure urinary pH, struvite crystals, and sediment concentrations. RESULTS: Daily food intake and dry-matter digestibility were significantly higher for the MM diet. Fecal moisture content also was higher for the MM diet. Apparent nitrogen (N) absorption and N retention were higher for the MM diet, even when values were expressed as a percentage to account for differences in N intake. Urinary pH, struvite activity product, number of struvite crystals in urine, and urinary sediment concentrations were not different between diets. Retention of calcium, phosphorus, and magnesium was lower for the CGM diet, and cats lost body calcium and magnesium when fed the CGM diet. CONCLUSIONS AND CLINICAL RELEVANCE: Meat meal was superior to CGM as a protein source in dry foods formulated for cats, because dry-matter digestibility and N utilization were higher for the MM diet. In addition, net loss of body calcium and magnesium for the CGM diet suggests that mineral requirements increase when CGM is used as a protein source.     

Intestinal supply of amino acids in sheep fed alkaline hydrogen peroxide-treated wheat straw-based diets supplemented with soybean meal or combinations of corn gluten meal and blood meal

The intestinal supply of amino acids (AA) in sheep fed alkaline hydrogen peroxide-treated wheat straw (AHPWS)-based diets supplemented with soybean meal (SBM) or corn grain plus combinations of corn gluten meal (CGM) and blood meal (BM) was measured in a 5 X 5 latin square. Sheep (avg wt 45 kg) with ruminal, duodenal and ileal cannulas were fed diets containing 65% AHPWS supplemented with the following protein sources: soybean meal (SBM), corn gluten meal (CGM), blood meal (BM), 2/3 CGM:1/3 BM and 1/3 CGM:2/3 BM. Total nitrogen (N) flow at the duodenum was not affected (P greater than .05) by protein source. Flows of bacterial N and AA increased (P less than .05) and flows of nonbacterial N and AA decreased (P less than .05) when wethers were fed SBM vs corn plus other protein sources. When diets contained SBM, quantities of total AA at the duodenum were lower (P less than .05) and the profile of AA supplied to the intestine was altered substantially. Total flows of AA at the duodenum and total quantities of AA disappearing from the small intestine were similar (P greater than .05) for all diets containing BM and CGM, but flows and disappearance of valine, histidine, lysine and arginine increased linearly (P less than .05), whereas flows and disappearance of leucine, isoleucine and methionine decreased linearly (P less than .05) as BM replaced CGM in the diets. Results suggest that quantities of individual AA flowing to the duodenum and disappearing from the intestine of wethers fed AHPWS-based diets can be altered by source of dietary protein. Furthermore, feeding protein sources resistant to ruminal degradation in combination may improve the profile of AA supplied to the intestine.     

Influence of supplemental nitrogen source on digestion of nitrogen, dry matter and organic matter and on in vivo rate of ruminal protein degradation

Seven Holstein steers (340 kg) fitted with ruminal, duodenal and ileal cannulae were used to measure the influence of supplemental N source on digestion of dietary crude protein (CP) and on ruminal rates of protein degradation. Diets used were corn-based (isonitrogenous, 12% CP on a dry matter basis, and isocaloric, 80% total digestible nutrients) with urea, soybean meal (SBM), linseed meal (LSM) or corn gluten meal (CGM) as supplemental N. Ruminal ammonia N concentrations were higher (P less than .05) in steers fed LSM than in those fed CGM, but did not differ from those in steers fed urea or SBM (11.7, 6.7, 9.1 and 9.2 mg/100 ml, respectively). Due to the high degradability of urea, ruminal digestion of dietary CP was greater (P less than .05) in steers fed urea than in those fed CGM, but intermediate in steers fed SBM and LSM (58.4, 48.8, 53.1 and 53.9%, respectively). Flow of bacterial nonammonia N to the duodenum was highest (P less than .05) in steers fed SBM or LSM, intermediate (P less than .05) for urea and lowest (P less than .05) for CGM (86.8, 86.1, 76.3 and 65.9 g/d, respectively). Efficiency of bacterial protein synthesis was lowest in steers fed CGM and differed (P less than .05) from SBM (15.6 vs 21.8 g N/kg organic matter truly digested, respectively). Rate of ruminal digestion for SBM-CP differed (P less than .05) from that of CGM-CP but not from that of LSM-CP (17.70, 5.20 and 10.13%/h, respectively). The slow rate of ruminal degradability of CGM resulted in increased amounts of dietary protein reaching the intestinal tract but lower amounts of bacterial protein, thus intestinal protein supply was not appreciably altered.     

Changes in gastric contents in pigs fed a finely ground and pelleted or coarsely ground meal diet.

The objective was to characterize the change in stomach contents in relation to time after feeding between pigs consuming a restricted amount of a finely ground and pelleted (FGP) or coarsely ground meal (CGM) diet. Particular interest was placed on the concentration of organic acids and ammonia, the products of microbial fermentation. Thirty barrows were ranked by weight and assigned to a postfeeding time of 2, 4, 6, 8, or 12 h and either the FGP or CGM diet. Initiation and termination of the experiment were staggered over a 2-wk period. The treatment period was 42 d. Percentage of dry matter was higher (P<.01) in the stomach contents of pigs on the CGM diet. Concentrations of pepsin and protein were higher (P<.05) and ammonia tended to be higher (P = .10) in the proximal stomach of pigs fed the FGP diet. In contrast, concentrations of acetate and L-lactate were higher (P<.05) in the proximal stomach of pigs fed the CGM diet. All pigs on the CGM diet had stomachs that graded as normal on visual inspection. There was variable damage to the stomachs of pigs on the FGP diet. Measurement of chromium concentration in the stomach after an oral dose of Cr-EDTA clearly demonstrated the mixing that occurs between the proximal and distal stomach by 2 h after feeding in pigs consuming the FGP diet, whereas a gradient was maintained in pigs consuming the CGM diet. Thus, components normally secreted in the distal stomach return to the proximal stomach. These data show that components secreted in the distal region, such as acid and pepsin, may play a role in initiating damage to the stratified squamous mucosa. High concentrations of organic acids in the stomach of pigs on the CGM diet were not associated with damage to the stratified squamous mucosa in the esophageal region.     

Effects of supplemental protein sources during the grazing period on performance, ruminal characteristics and blood constituents in early weaned growing Wagyu steer calves

We investigated the effects of grazing and supplemental protein sources during the grazing period on growth performance, ruminal characteristics and blood constituents in 15 growing Wagyu steer calves weaned at 3 months of age. Each animal was allotted one of three treatments: (1) GSBM, soybean meal (SBM) supplemented as a protein source during a grazing period; (2) GCGM, corn gluten meal (CGM) supplemented as a protein source during a grazing period; or (3) NG, no grazing, in which steers were fed hay and GSBM concentrate only. The estimated rumen undegradable protein (RUP) concentration of CGM was higher than that of SBM. High RUP supplementation during the grazing period did not influence feed intake or growth performance. Compared with the NG treatment, the average daily gain in GSBM and GCGM calves was significantly depressed (P < 0.05). Bodyweight/withers height ratio in the NG calves tended to be greater than in the GSBM and GCGM calves. Final paunch girth/heart girth ratio in the GSBM and GCGM calves was significantly greater (P < 0.05) than in the NG calves. Supplementation with CGM did not influence ruminal ammonia nitrogen and blood constituents. These results indicate that CGM supplementation during the grazing period did not enhance the growth of Wagyu calves because the CGM diet probably did not elevate the metabolizable protein supply to the grazing calves above that of the SBM diet in our conditions.     

味精菌体蛋白对鸡蛋白质和氨基酸利用率的影响

选用24只2 kg左右的蛋公鸡,随机分组进行4个处理,每个处理6只鸡。前3个处理分别给每只鸡强饲占体重4%的待测原料(豆粕、玉米蛋白粉和味精菌体蛋白),第4个处理作为内源对照组,测定内源排泄量,以评定味精菌体蛋白对鸡蛋白质和氨基酸利用率的影响。结果表明,味精菌体蛋白粗蛋白含量达到71.45%,分别比豆粕和玉米蛋白粉高64.03%和22.32%;味精菌体蛋白粗蛋白表观消化率和真消化率、总氨基酸表观消化率和真消化率均极显著低于豆粕和玉米蛋白粉(P<0.01);而干物质表观消化率和真消化率三者间无显著差异(P>0.05);在已测定的17种氨基酸中,除甘氨酸外,味精菌体蛋白粉其他氨基酸表观消化率和真消化率均极显著低于豆粕和玉米蛋白粉(P<0.01)。这表明味精菌体蛋白的蛋白质和氨基酸利用率低于豆粕和玉米蛋白粉。