Impairment of the peripheral lymphoid compartment in iron-deficient piglets

The aim of this study was to investigate the effect of neonatal iron deficiency on immune functions in young piglets. While control piglets were not given any iron preparation until the age of 21 days, another group of piglets was given 200 mg of Fe(3+)-dextran i.m. on day 3. Red blood cell parameters in the former, iron-deficient group were characteristic of hypochromic anaemia. In addition, the total leucocyte count (P < 0.01), relative and absolute neutrophil count (P < 0.01) and absolute lymphocyte count (P < 0.05) in peripheral blood were found significantly lower in iron-deficient piglets than in their iron-supplemented counterparts. Lymphocyte activity as measured by in vitro lymphocyte transformation test was impaired in iron-deficient piglets. A statistically significant decrease in circulating B-lymphocyte numbers was found in non-supplemented animals. Iron deficiency apparently negatively influenced the immunocompetence in piglets.     

Effects of dietary cottonseed meal and iron-treated cottonseed meal in different laying hen genotypes

The effects of dietary screw-pressed cottonseed meal (CSM) and iron-treated CSM on laying performance and discolourations in eggs were examined in a range of hen genotypes. In experiment 1, six genotypes, obtained at point-of-lay from various sources, were fed on a non-CSM diet, a diet with 300 g CSM/kg, and a diet containing iron-treated CSM at 300 g/kg. In experiment 2, two of these genotypes were reared together from day-old and were fed from 10 to 18 weeks on a non-CSM diet or a diet containing iron-treated CSM at 250 g/kg. They were then fed on a non-CSM layer diet or a diet containing iron-treated CSM at 300 g/kg, in a 2 x 2 x 2 factorial design that also examined the effects of the rearing diet. 2. The effects on food intakes and egg production of including CSM and iron-treated CSM in layer diets depended on the genotype of the hens. The strongest interaction between breed and diet was on food intake, the breed Hubbard Golden Comet (HGC) being the least tolerant of CSM and iron-treated CSM. 3. Inclusion of iron-treated CSM in the rearer diet to supply approximately 70% of the dietary protein had no adverse effects on growth or age at first egg. Food intake and egg production between 18 and 26 weeks were affected by the iron-treated CSM layer diet, but there were no carry-over effects attributable to the rearing diets. 4. Genotype was not a factor in the development of the gossypol-related brown yolk discolouration in fresh or warm-stored eggs of hens fed on a CSM-based diet containing 197 mg free gossypol/kg and 52 mg cyclopropenoid fatty acids (CPFA)/kg (experiment 1). 5. In both experiments, the susceptibility of eggs to the CPFA-related cold storage effects depended on the genotype of the hen, eggs from hens of the HCG breed being more affected than those of ISA hens. 6. Treatment of CSM with crystalline ferrous sulphate heptahydrate, at a 4:1 weight ratio of iron to free gossypol, prevented brown yolk discolourations in all genotypes tested, as assessed by subjecting egg yolks to atmospheres of ammonia, and cold storage of eggs.     

Gastrointestinal volatile fatty acid concentrations and pH in cats

OBJECTIVE: To measure volatile fatty acid (VFA) concentrations and pH in the gastrointestinal tracts of healthy adult cats fed a commercial dry cat food. ANIMALS: 14 cats. PROCEDURE: The gastrointestinal tracts were excised immediately after euthanasia and divided into 6 sections (stomach, duodenum, jejunum, ileum, proximal portion of the colon, and distal portion of the colon). Luminal contents were collected from each segment, pH was measured, and contents were centrifuged. The supernatant was analyzed for acetate, proprionate, butyrate, isobutyrate, valerate, and isovalerate concentrations by use of gas chromatography. RESULTS: Mean total VFA concentrations were lowest in the stomach (20 mmol/L); increased through the duodenum, jejunum, and ileum (30, 29, and 41 mmol/L, respectively); and were greatest in the proximal and distal portions of the colon (109 and 131 mmol/L, respectively). Estimated mean total VFA amounts were low (<600 micromol) throughout all segments of the gastrointestinal tract; pH values increased from the stomach through the ileum and subsequently decreased in the colon. CONCLUSIONS AND CLINICAL RELEVANCE: Total VFA concentrations in the colon were comparable to values reported for the forestomach of ruminants and large intestines of monogastric animals, whereas values in the small intestine were higher than reported for other species. Total VFA amounts were low, consistent with the short, nonvoluminous gastrointestinal tract of carnivores. Luminal pH varied throughout the gastrointestinal tract in a pattern similar to other monogastric animals. Volatile fatty acids probably contribute minimal metabolic energy in cats but may be important in the maintenance of local mucosal health.     

Gastric structure and function in iron-deficient piglets

Gastric motility, secretion and structure were studied in piglets which were weaned at two weeks of age and reared in iron-free cages on a low-iron diet. Piglets which were not given iron parenterally rapidly developed iron deficiency anaemia. Gastric motility was studied fluoroscopically after dosing the piglets with barium sulphate. Gastric secretion was studied in piglets with gastric cannulae after stimulation with betazole hydrochloride. There was no difference between iron-treated and iron-deprived pigs in the motility of the stomach but in iron-deprived animals there was marked impairment of acid and chloride secretion from an early age and histological evidence of atrophic gastritis.     

青藏高原种植紫穗槐对土壤养分的响应

选取在西藏拉萨地区人工种植的两龄紫穗槐为研究对象,探讨了灌丛内与灌丛外土壤各种形态氮素、全磷、有机碳的含量特征及土壤pH的差异。结果表明,1)相对于灌丛外土壤,灌丛内土壤的全氮、铵态氮、硝态氮分别平均高23.44%,13.95%和37.60%,土壤全磷平均高19.57%,土壤有机碳平均高44.21%,土壤pH值平均低1.69%。2)灌丛内与灌丛外土壤的全氮、铵态氮、硝态氮、全磷、有机碳、pH均差异显著(P<0.05)。3)垂直方向上,灌丛内和灌丛外在10~20 cm土层的全氮、铵态氮、硝态氮、全磷均为最高,有机碳和pH则随土层深度增加而递减。4)土壤各营养元素之间表现为不同程度的相关性,土壤有机碳与铵态氮呈极显著正相关关系(P<0.01),与全磷呈显著正相关关系(P<0.05);全氮与全磷呈极显著正相关关系(P<0.01);铵态氮与全磷呈极显著正相关关系(P<0.01)。     

Effect of fiber source on cecal fermentation and nitrogen recycled through cecotrophy in rabbits

The influence of fiber source on fiber digestion in rabbits was investigated. Six fibrous feedstuffs with wide differences in chemical composition and particle size were selected: paprika meal, olive leaves, alfalfa hay, soybean hulls, sodium hydroxide-treated barley straw, and sunflower hulls. Six diets were formulated to contain one of these ingredients as the sole source of fiber. To avoid nutrient imbalances, fiber sources were supplemented with different proportions of a fiber-free concentrate, based on soy protein isolate, wheat flour, lard, and a vitamin and mineral mix, to obtain diets containing at least 3% nitrogen and 5% starch. Daily soft feces excretion, and its NDF, and total and microbial nitrogen content were determined in 60 fattening rabbits (10 per diet). Seven days after the last cecotrophy control, the same animals were used to determine weight of stomach, cecum and their contents, and cecal fermentation traits (pH, VFA and ammonia concentrations, and buffer properties of cecal contents). Stepwise regression analysis showed a positive effect (P < .001) on soft feces excretion, total and microbial nitrogen concentrations in soft feces, cecal acidity, and total VFA in the cecum of dietary pectic constituents (2.9, 3.5, 2.5, .9, and 6.6%) and proportion of fine particles (< .315 mm) (1.8, .9, 1.3, .15, and .9%) per each increment of one percentage unit of the independent variables. Proportion of fine particles also increased weight of cecal contents (P < .001). Soft feces excretion and weight of stomach and of its contents increased (P < .001) by 5.2, 2.8, and 10.2% per each percentage unit increment of proportion of large particles (> 1.25 mm). Degree of lignification of NDF decreased total nitrogen concentration in soft feces and cecal VFA concentration (P < .001). Source of fiber affected cecal pH not only by its influence on the cecal concentrations of the final products of fermentation, but also through its effect on the pH of dry cecal contents (P < .001). The latter was negatively correlated with dietary proportion of fine particles, degree of lignification of NDF, and base-buffering capacity of dry cecal contents (r = -.52, -.37, and -.49, respectively). From these results, we conclude that pectic constituent concentration, degree of lignification of NDF, and particle size are the variables that best characterize the influence of the source of fiber on soft feces excretion and cecal fermentation traits in rabbits.     

补饲精料对西藏彭波半细毛羊羊肉品质的影响

本试验旨在研究补饲精料对西藏彭波半细毛羊羊肉品质的影响。选择30只成年彭波半细毛羊母羊,按照同质原则随机分为3组:放牧不补饲(对照,G1)组、补饲精料200 g/d(G2)组、补饲精料400 g/d(G3)组,每组10只。每天19:30补饲,正试期75 d。正试期结束屠宰,采集背最长肌测定营养物质含量和组织结构特征。结果表明:高水平补饲精料提高了母羊总干物质采食量,G3组平均日增重显著高于G1、G2组(P0.05);补饲精料对羊肉p H1 h、p H24 h、滴水损失及水分和粗灰分含量无显著影响(P0.05),但G3组的熟肉率,粗蛋白质、肌内脂肪含量,肌纤维密度显著高于G1组(P0.05);G2、G3组羊肉总氨基酸、必需氨基酸和天冬氨酸含量显著高于G1组(P0.05),G3组苯丙氨酸、赖氨酸含量显著高于G1组(P0.05),G3组苏氨酸、谷氨酸含量有高于G1组的趋势(0.05≤P0.10);补饲精料对羊肉饱和脂肪酸、单不饱和脂肪酸和多不饱和脂肪酸含量没有显著影响(P0.05),G3组C18∶1 trans-9含量有低于G1组的趋势(0.05≤P0.10)。上述结果表明,补饲精料能显著提高彭波半细毛羊羊肉营养价值,改善肉质嫩度,每只补饲400 g/d优于200 g/d。     

Effects of iron dextran injections on the incidence of abomasal bloat, clinical pathology and growth rates in lambs

A preliminary study revealed significantly lower serum iron concentrations in lambs that developed abomasal bloat about one week later, than in lambs that did not develop bloat. In a subsequent trial, with 754 naturally reared twin lambs from five flocks, iron dextran injections were found to have a preventive effect on the development of abomasal bloat. Clinical signs of abomasal bloat were observed in the placebo-treated lamb of 16 couples and in the iron-treated lamb of six couples (P<0.05). In three further couples, both lambs developed bloat. The iron-treated group had significantly (P<0.001) better average weight gains, both from birth to summer, and from birth to autumn of approximately 0.5 and 1 kg, respectively. There was a reduction in red blood cell values and iron saturation in the placebo group 14 days after treatment but not in the iron-treated lambs. In one of the flocks, there was a decrease in the cumulative incidence of abomasal bloat from 37 per cent to 3 per cent during the period of four years after measures such as later lambing, earlier turnout and iron injections were introduced.     

Effect of a hay and a grain diet on the rate of hydrolysis of ochratoxin A in the rumen of sheep

The hydrolysis of ochratoxin A (OA) and the corresponding formation of its hydrolysis product, alpha ochratoxin (O alpha), by ruminal digesta and in the rumen of hay-fed and grain-fed sheep were compared. Ruminal contents from sheep fed diets with hay or with grain hydrolyzed OA in vitro; the majority of the activity was associated with the particulate fraction of the ruminal contents. The rate of hydrolysis of OA by ruminal fluid that was adjusted to different pH values was not influenced (P greater than .6) by the pH of the samples (pH was from 5.5 to 7.0). Ruminal fluid obtained from hay-fed animals (pH 7.0) was able to hydrolyze OA in vitro and to produce the hydrolyzed product, O alpha, at a much greater rate (fivefold) than ruminal fluid obtained from grain-fed animals (pH 5.5) (P less than .01). Ochratoxin A was administered intraruminally at a concentration of .5 mg/kg of BW to hay-fed and grain-fed sheep. The half-lives for disappearance of OA from the rumen of sheep fed grain (normal feed intake, rumen pH 5.7), fed grain at a low level (30% of normal feed intake, pH 6.5), and fed hay (pH 7.1) were 3.6, 1.3, and .6 h, respectively. The results suggest that OA is hydrolyzed much faster in the rumen of sheep fed hay than in sheep fed grain, presumably because of the different ruminal microbial population, which in turn influenced the rate of hydrolysis of OA.     

Abomasal contents of parasitised sheep contain an inhibitor of gastrin secretion in vitro

Serum gastrin concentrations are typically elevated in parasitised sheep; however, in some animals serum gastrin concentrations may fall abruptly despite a very high abomasal pH. Although proliferating abomasal bacteria in culture generate a potent inhibitor of in vitro gastrin secretion, this inhibitor has not been detected in abomasal contents of unparasitised sheep. In sheep parasitised by O. circumcincta, all abomasal fluid samples of pH 5 and above were inhibitory to gastrin release in vitro. Inhibitory activity and abomasal pH were correlated in two separate experiments; the model best fitting the data being sigmoidal in each case, with zero activity at pH 3.6 and 4.6, respectively. There was no clear evidence that the presence of a gastrin inhibitor in the abomasal contents reduced the serum gastrin concentration in parasitised sheep. Serum gastrin was correlated with abomasal pH (log(10) serum gastrin concentrations conformed to log-linear sigmoidal models).     

The first occurrence of demodicosis in cattle in Czechoslovakia

Demodectic lesions were found in 37 per cent out of the total number of seventy-five cows examined by palpation in a large cow-house in South Bohemia, Czechoslovakia. These lesions were intradermal nodules, mostly 2 to 6 mm in diameter, located in the corium in the anterior parts of the body. The animals had 1 to 75 lesions (on the average 11.6). Their age was three to seven years. Their overall health condition was good and their behaviour was not affected. Microscopic examination revealed large numbers of Demodex bovis Stiles, 1892, causative agent of demodicosis, in the contents of nodules in five out of six examined animals. Histopathological changes in two nodules were characterized by inflammatory granulomatous structures containing large numbers of mites, epithelioid cells with rich, pale cytoplasm, giant cells of the foreign body type, and inflammatory infiltrates consisting mostly of lymphocytes. Fibroproduction in the contents of granulomas and along their periphery was markedly low.     

The Effect of Experimental Methyl Mercury Poisoning on the Distribution of Acid Phosphatase During Autolysis in Cat Liver

Seven healthy male cats weighing between 2.35 and 4.30 kg were daily fed a diet which contained Hg²⁰³ labelled methyl mercury hydroxide in liver homogenate. Eight additional cats were kept as controls on a similar diet without methyl mercury hydroxide. The daily amount of methyl mercury hydroxide fed to the cats, expressed as inorganic mercury, varied between 3.75 and 4.33 mg per cat. When the animals had developed neurological symptoms typical of methyl mercury poisoning, they were decapitated and their livers removed for the determination of the mercury content, the distribution of acid phosphatase during autolysis at 37°G, the pH and the total bacterial count before and after a 24 hr. period of autolysis. Similar determinations except for the mercury were made from the livers of the control animals. The total amount of methyl mercury hydroxide fed to the cats varied between 29.14 and 40.12 mg Hg++ per kg of body weight, and the mercury content in their livers between 102.5 and 128.7 mg Hg++ per kg of liver wet weight.The share of un sedimentable activity of acid phosphatase out of the total immediately after decapitation was found to be significantly (P < 0.001) greater in the livers of the methyl mercury-fed cats than in the livers of the control animals. After 12 to 24 hrs. of autolysis at 37 °G the unsedimentable activity accounted for 100 % of the total acid phosphatase activity in the livers of 6 of the 7 methyl mercury-fed animals, while in the livers of the controls the corresponding percentages varied after 24 hrs. of incubation between 42 and 73, the mean being 57.4 ± 11.4 %. The mean pH of the livers of the methyl mercury fed animals was found to be significantly higher before (P< 0.001) and after (P < 0.001) a 24 hr. incubation at 37 °G than the corresponding mean pH values of the control animals.Because of the injection of antibiotics given to the cats before sacrifice the total bacterial count of the livers, which was checked before and after a 24 hr. incubation at 37°G, was found to be zero.     

Feeding value of total mixed ration silage with spent mushroom substrate

Six wethers were used in a digestibility experiment arranged as replicated 3 × 3 Latin square to evaluate the nutritive value of total mixed ration (TMR) silages that were made from ensiling of TMR containing 0, 6.5 and 13.0% (dry matter basis) of spent mushroom substrate (SMS) for 45 days (treatments denoted as CSMS, LSMS and HSMS, respectively). The amount of SMS replaced the same amount of timothy hay in the respective TMR. All TMR were well preserved as indicated by their low pH, low ammonia‐N and high lactic acid contents. Increasing levels of SMS in the TMR silage quadratically reduced (P < 0.05) nutrient digestibility with the exception of ether extract. The difference of total digestible nutrients and digestible energy contents between LSMS and CSMS TMR silage were less than those between LSMS and HSMS. Increasing concentration of SMS in the ration tended to decrease content of total volatile fatty acids in rumen fluid but increased the ratio of acetate to propionate and pH. The study suggests that a SMS level of 6.5% in the diet DM can be recommended for silage based TMR.     

甘氨酸亚铁对断奶仔猪生长性能、铁表观消化率及血清铁相关指标的影响

本试验旨在研究甘氨酸亚铁对断奶仔猪生长性能、铁表观消化率及血清铁相关指标的影响。试验选取12头(28±1)日龄"杜×长×大"断奶仔猪,根据体重、健康状况等均衡分布原则分为2组,每组6个重复,每个重复1头仔猪,单个饲养于消化代谢笼。试验分为2个阶段,第1阶段:2组均饲喂缺铁基础饲粮10 d,使仔猪处于临近贫血状态;第2阶段:对照组在缺铁基础饲粮中额外添加100 mg/kg的硫酸亚铁(以铁计),试验组额外添加100 mg/kg的甘氨酸亚铁(以铁计),试验期10 d。结果表明:与添加硫酸亚铁相比,饲粮添加甘氨酸亚铁有降低仔猪料重比的趋势(P0.10),降低了4.57%,但对仔猪的平均日增重、平均日采食量无显著影响(P0.10);饲粮添加甘氨酸亚铁能显著降低粪中的铁排出量和铁排出总量(P0.05),分别降低了23.11%和22.09%;饲粮添加甘氨酸亚铁能极显著提高铁表观消化率和表观代谢率(P0.01),分别提高了13.34%和22.42%;同时,饲粮添加甘氨酸亚铁能显著提高血清中的铁饱和度和血液中的铁含量(P0.05)。综上,甘氨酸亚铁可提高断奶仔猪的生长性能,提高血液铁含量,改善仔猪铁代谢状况,降低粪便铁排出量,是一种绿色高效的新型补铁剂。     

阴山北麓不同土地利用类型土壤养分特征分析与评价

采用野外实地调查采样、室内样品分析和数理统计相结合的方法,研究了阴山北麓4种不同利用类型土地的土壤养分特征,并对土壤肥力进行了综合评价。结果表明,1) 研究区土壤有机质、全氮、全磷、全钾含量分别为(25.12±6.56),(0.63±0.08),(0.76±0.10),(31.99±1.07) g/kg;速效氮、速效磷、速效钾含量分别为(39.87±9.14),(6.72±3.75),(175.83±105.45) mg/kg;pH为(7.74±0.14)。2) 土地利用方式对有机质、全氮、全磷、速效磷和速效钾的影响极显著(P<0.01),而对速效氮、全钾和pH的影响不显著(P>0.05)。3) 土壤全氮、磷、钾含量和pH值在垂直剖面上(0~25 cm自上而下)表现为无规律的波动状态,但整体上变幅不大;而速效氮、磷、钾和有机质含量整体上表现为下降趋势。4) 土壤肥力综合评价值的排序为封育草地(0.506)>放牧草地(0.417)>耕地(0.361)>弃耕地(0.357),封育草地与放牧草地的土壤肥力为中等级水平,而耕地和弃耕地的肥力为低等级水平,说明草地比耕地更有利于土壤保肥。总体而言,研究区土壤肥力水平较低,存在的主要问题是土壤中全氮和速效氮含量严重偏低。     

三峡水库城区消落带人工草本植被土壤养分含量研究

为研究三峡水库城区消落带人工植被种植后,经不同淹水时间土壤的化学特性变化规律,及探讨城区消落带植被重建对库区水质的潜在影响,分别对2012年6月、2013年3月、2013年5月、2013年7月、2013年9月城区消落带扁穗牛鞭草(Hc)、狗牙根(Cd)、小巴茅(Ss)和裸地土壤的pH值和养分含量进行了调查研究。结果表明,植被类型对土壤pH值、碱解氮(AN)、有效磷(AP)、全磷(TP)含量有显著影响。综合而言,与裸地相比,人工草本植被土壤pH值和养分含量无显著差异。该区土壤pH值在6.5~8.5间波动。不同淹水时间的城区消落带土壤营养元素含量间存在较大差异。随取样时间的延长,裸地和人工植被土壤pH值、有机质含量呈波动变化。AN含量在2013年3月、2013年9月消落带刚开始落干时较高。然而,AP含量在2012年6月最大,此时,裸地、扁穗牛鞭草、狗牙根、小巴茅土壤AP含量分别为(2.62±0.30),(3.92±0.34),(1.08±0.16),(1.24±0.06) mg/kg。土壤全磷、全钾含量则在研究后期有所增加。研究表明,除地表植被、水文因素外,城市污水排放、强烈人为干扰、地表径流带来的点/面源污染等也影响该城区消落带土壤营养元素含量。对于三峡库区长江重庆主城区河段而言,由人工草本植被构建造成的水体富营养化程度有限。     

Proteinase, lipase and amylase activities in the small intestine of pigs suffering from colienterotoxaemia.

The activities of proteinases, lipases, amylases and the activities of proteinase inhibitors, as well as the numbers of Escherichia coli in the contents from the small intestine were examined for pigs suffering from colienterotoxaemia and for healthy pigs. Enzyme activities were determined using an agar diffusion test.Compared with healthy animals the activities of proteinases and amylases in diseased animals were reduced while lipases showed increased activity. In pathologically changed contents showing large numbers of E. coli, proteinases could not be demonstrated; however, proteinase inhibitors were found in these contents. In healthy animals, proteinase inhibitors were not demonstrated in ingesta-con-taining contents.In diseased animals, E. coli were found in large numbers in all parts of the small intestine. In healthy animals, E. coli was demonstrated especially in the posterior part of the small intestine and regularly in small numbers.The possible influence of digestive enzymes, especially proteinases and their inhibitors, on enterotoxins from E. coli is discussed.     

0～56日龄舍饲肉用羔羊前胃功能发育研究

选用甘肃肉用绵羊新品种选育群公羔(单羔)45只,分为9组,每组5只,分别于0,7,14,21,28,35,42,49和56 d屠宰、取样,测定与前胃功能发育相关的内容物相对重量、pH值及瘤胃内容物 VFAs、主要微生物消化酶等指标的变化规律。结果表明,羔羊瘤网胃内容物相对重量(%全胃内容物重量)在0～35 d呈线性增加(R²=0.93,P=0.00),在28 d时为61.54%,35 d时为76.87%;瘤胃、网胃和瓣胃均具有较低的pH值,分别为5.30～6.03,5.37～6.42和5.39～6.15;瘤胃以乙酸发酵类型为主导,内容物A/P为2.18～3.82,丙酸含量较高;瘤胃内容物中微生物蛋白酶、α-淀粉酶和纤维素酶活性较高的日龄分别出现在21,7和14 d。在本试验条件下,羔羊在28 d时前胃功能发育已基本完成。舍饲并于7 d开始补饲的饲养方式下,于35 d或提早至28 d对羔羊开展早期断奶可行。     

Effects of dietary calcium and available phosphorus concentration on digesta pH and on the availability of calcium, iron, magnesium and zinc from the intestinal contents of meat chickens

1. The effects of high calcium intakes on the pH and availability of calcium, iron, magnesium and zinc in the gastrointestinal tract (GIT) contents of meat chickens were studied in two experiments. 2. A high dietary concentration of calcium (25.3 vs 10.7 g/kg) increased the pH of crop and ileum contents, but did not influence the pH of the contents of other segments of the GIT. 3. The solubilities of minerals in GIT contents were reduced and the size of dissolved mineral complexes were increased as the digesta moved from the duodenum and jejunum to the ileum. 4. After feeding diets with calcium and available phosphorus concentrations (15.3 and 4.3 g vs 21.8 and 4.3 g vs 22.6 and 8.3 g/kg), centrifugation of GIT contents showed that most (70-92%) of the calcium, iron, magnesium and zinc was in an insoluble form. High calcium diets reduced the proportion of soluble zinc associated with small complexes, and high calcium and available phosphorus diets reduced the proportions of soluble magnesium and zinc associated with small complexes. 5. These findings explain the mechanism of the reduced availability of zinc and magnesium in high calcium and high available phosphorus diets.     

Effects of iron deficiency on viability of Trichinella spiralis larvae in vitro

The importance of iron for survival of Trichinella spiralis larvae in vitro was examined. It was found that iron-deficient media drastically reduce the survival of this larva. Also, molting of the larvae was observed in the control media but not in the iron-deficient media.