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1.
在建立猪粪中洛克沙胂HPLC检测方法基础上,选用24头育肥猪,分别混饲给予0、25、50、100 mg/kg洛克沙胂,混饲给药后不同时间采集粪样,以高效液相色谱法测定其中洛克沙胂质量浓度,了解洛克沙胂混饲给药后在猪体内的排泄情况,然后从江苏和山东省15个使用洛克沙胂的集约化猪场采集150头猪的粪样,调查猪粪样中的洛克沙胂含量。结果表明,所建立的猪粪中洛克沙胂HPLC检测方法的平均回收率为82.09%~84.03%,变异系数为2.92%~5.45%,检测限为0.05 mg/kg,定量限为0.1 mg/kg;以不同剂量混饲给药后,洛克沙胂在粪中排泄量在36~48 h达峰,峰质量浓度分别为12.31、22.52、34.78 mg/kg,猪粪中检测不到洛克沙胂的时间分别为72、108、132 h;所调查150个粪样中洛克沙胂平均质量浓度为23.13 mg/kg。  相似文献   

2.
Three experiments were conducted to investigate the roxarsone (3-nitro-4-hydroxyphenylarsonic acid) X copper (Cu) interaction in weanling pigs. Supplemental roxarsone at 400 mg/kg diet decreased rate and efficiency of weight gain and caused visible neurological signs of toxicosis. Copper addition (CuSO4 X 5H2O) at a level of 650 mg Cu/kg diet likewise decreased weight gain and feed efficiency, and it also increased hepatic Cu deposition. The combination of these growth-depressing dosages of roxarsone and Cu resulted in a far greater reduction in gain and efficiency of feed utilization than was the case when either compound was fed alone. A growth-promoting dosage of Cu (250 mg/kg) increased weight gain by 32% in one experiment but showed no efficacy in alleviating the growth-depression resulting from feeding 400 mg/kg roxarsone. A roxarsone dosage of 100 mg/kg increased gain and feed efficiency. Surprisingly, the decreased weight gain in pigs fed 650 mg/kg Cu was ameliorated by feeding 100 mg/kg roxarsone concomitantly. This level of roxarsone also reduced liver Cu concentration substantially. It thus appears that the nature of the roxarsone X Cu interaction is dependent on the dose of each compound administered. Moreover, low-dose roxarsone administration appears to ameliorate Cu toxicity, but low-dose Cu feeding does not show efficacy against roxarsone toxicity.  相似文献   

3.
Effects of feeding sulfadimethoxine and ormetoprim to sows and gilts in late gestation were evaluated. One sow and 2 gilts were randomly selected and were fed 1 of 3 rations: (1) a gestation ration from farm A, where congenital goiter in newborn pigs was a problem, (2) gestation ration from farm A containing 275 g of sulfadimethoxine and 55 g of ormetoprim/100 kg of ration, or (3) standard swine gestation ration containing 275 g of sulfadimethoxine and 55 g of ormetoprim/100 kg of ration. Sows and gilts were fed the appropriate ration for 22 to 58 days before farrowing. The numbers of stillborn or weak pigs did not increase in any group. However, congenital goiter was detected in all pigs from swine fed medicated rations 2 and 3. Congenital goiter was not present in pigs from swine given gestation ration 1.  相似文献   

4.
本研究通过断奶仔猪、生长猪和肥育猪3个试验研究了日粮添加洛克沙胂对猪生产性能及血液指标的影响。试验分别选择96头杜×长×大三元杂交断奶仔猪(8.29±0.99)kg、生长猪(32.68±3.43)kg和肥育猪(62.74±8.89)kg,随机分为4个处理,每个处理6个重复,每个重复4头猪,公母各半。处理1为对照组,日粮中不添加洛克沙胂,处理2、3和4分别在日粮中添加50、100 mg/kg和150 mg/kg洛克沙胂。基础日粮为玉米-豆粕型,各处理日粮营养水平均为等能量、等蛋白。结果表明:日粮中添加洛克沙胂能显著提高断奶仔猪与生长猪日增重和饲料转化效率(P<0.05),减少仔猪腹泻率(P<0.01)。但对肥育猪增重效果不明显(P>0.05);日粮中添加洛克沙胂使动物血红蛋白、肌酐和谷草转氨酶含量升高,白蛋白含量降低(P<0.05)。表明洛克沙胂对猪具有一定的促生长效果,可增加动物血液运氧能力,但同时有可能对动物肝脏、肾脏造成一定损伤。  相似文献   

5.
Experimental 3-nitro-4-hydroxyphenylarsonic acid toxicosis in pigs   总被引：2，自引：0，他引：2  
Five times the recommended dose of 3-nitro-4-hydroxyphenylarsonic acid (187.5 mg kg-1) induces a pathognomonic clinical syndrome in pigs. The main clinical features are not continually present but are inducible only by exercise. From day 11 on the experimental diet a nervous syndrome was inducible. This manifested as muscle tremors and clonic convulsive episodes. Paraparesis developed by day 22 and paraplegia by day 33. Liver arsenic levels plateaued at 5.4 +/- 1.3 mg kg-1. The experiment confirms field observations that 3-nitro produces a characteristic toxicological syndrome, which is distinct from that of arsanilic acid. It also confirms that 3-nitro has a higher absolute toxicity than arsanilic acid in pigs as well as a lower margin of safety.  相似文献   

6.
Chronic copper toxicity in a dairy herd   总被引：3，自引：2，他引：1       下载免费PDF全文
The addition of excessive copper to a commercially prepared dairy ration caused chronic copper toxicity in a dairy herd. A formulation error by a feed company resulted in copper levels of 800 to 1,000 mg/kg in the “as fed concentrate,” amounting to about 400-500 mg copper/kg of the whole ration. Five animals died with typical signs of acute copper toxicity, including intravascular hemolysis and methemoglobinemia. A further 39 cows died on the farm from a combination of debilitation and secondary infectious causes, and 215 were sent to slaughter because of debilitation and poor milk production. The mortality of calves born to dams that had been fed the toxic concentrate was approximately 50%.

We postulate that dairy cows, particularly pregnant cows, may be more susceptible to copper toxicity than other cattle, and suggest reexamination of the presently allowable maximum levels of copper supplementation of diets for dairy cattle.

  相似文献   

7.
In three experiments with fattening pigs the supplementation of a ration with 8% rapeseed oilmeal (RSO) with 1 mg J/kg resulted in an increased weight gain per day of 31, 94 and 87%. On the other hand, only 83, 76 and 84% of the weight gain of the soybean oilmeal control groups were achieved. The additional supply with 250 mg Cu (experiments II and III) increased the weight gain to 84 and 96% in comparison to the unsupplemented control groups. The combination of J + Cu + Zn lead to the same performance as that of J + Cu (experiment III). In the RSO groups without J-supplement changes in body proportions and parakeratosis could be observed after approximately equal to 7 weeks. After the sole supplementation of Cu these symptoms occurred approximately equal to 4 weeks later. In vitro, the supplementation of RSO with a CuSO4 solution resulted in a decrease of vinylthiooxazolidon and isothiocyanate in line with the CuSO4-concentration. 0.2 mg J/kg feed (experiment III) resulted in the same fattening performance as the supplementation of the ration with 1 mg J and outwardly visible deficiency symptoms. The results show that Cu, depending on its quota, results in a decrease of goitrogenics in the feed and that J and Cu supplementation to rations with rapeseed oilmeal have an additive effect and that parakeratosis can be prevented by J-supplementation.  相似文献   

8.
Studies on vitamin B6 and pantothenic acid conducted with pigs, poultry and veal calves are presented to demonstrate the difficulties involved in research on B vitamins. The analysis of the B vitamins already poses problems, so that recommendations on dietary requirement must be seen in the light of the respective analytical procedures used. A distinction must be made between the minimum and optimum requirements of the animals. Today, the dietary provision of the optimum requirements is of priority and needs suitable and sensitive biochemical criteria or performance criteria for assessment.Studies using early-weaned and market pigs demonstrate that, in the case of vitamin B6, the urinary xanthurenic acid secretion after a tryptophan load and the activities of the serum transaminases are suitable biochemical criteria to diagnose suboptimum supply. Though these criteria were less responsive in poultry than in pigs, nevertheless, when the supply of vitamin B6 was suboptimal in broiler chicken, the body's retention of dry matter, nitrogen and energy, providing measures of true performance, proved to be affected adversely.The assessment of the optimum vitamin B requirement for practical feeding rations is illustrated with results from studies on the pantothenic acid requirement of broilers and market pigs. On the basis of live weight gain and feed efficiency, and also taking into consideration biochemical criteria provided by pantothenic acid and coenzyme A levels in the blood and liver, an optimum pantothenic acid requirement of 8 mg per kg of feed is recommended for broilers and 9 mg per kg of feed for market pigs. The dietary requirement of piglets, market pigs and broilers for vitamin B6 is estimated to be 3 mg per kg of feed.  相似文献   

9.
Paper containing colored inks from magazines and newspapers was fed as 23% of their ration to sheep for 175 days. A similar ration containing oat hulls in place of the paper was fed to control animals. The paper-fed animals consumed 29% more feed than the controls but the feed efficiency (kg animal weight gained/kg ration consumed) of the two rations was approximately equivalent. Lead contained in the paper accumulated in animal tissues. Hepatic microsomal mixed function oxidase activity was several fold higher in the paper-fed animals than the controls. Histopathologic examination of liver and kidney using light and electron microscopy revealed no lesions attributable to diet.  相似文献   

10.
Aflatoxin (AF)-contaminated ground corn was mixed with a commercial swine ration to yield 2 concentrations (500 mg of AFB1/kg of feed [A] and 300 mg of AFB1/kg [B]) and was fed to 2 groups of pigs. Groups A and B were fed the AF-containing ration, whereas control group C was fed the same commercial ration mixed with ground corn devoid of AF. A comparative analysis of the average weight gain per pig in each of the treatment groups, compared with that in the control group, indicated a significantly (P less than 0.01) greater weight gain in the control group. The average feed conversion rate was also significantly (P less than 0.01) lower in group A pigs, compared with that in the control group. The humoral immune response to Erysipelothrix rhusiopathiae, measured by enzyme-linked immunosorbent assay, did not reveal a significant difference among groups; there were no consistent differences observed in the proliferative responses of lymphocytes to mitogens. In contrast, a significant (P less than 0.05) reduction in complement titers was observed, whereas an increase in serum immunoglobulin G and M values occurred in the AF-treated group A, compared with that in group C. Gross enlargement of the liver, substantiated by histologic evidence of toxic damage to the hepatic parenchyma, revealed that AF at concentrations of 500 mg/kg of feed was toxigenic and produced an adverse effect on the growth rate, feed efficiency, and general well-being of young pigs.  相似文献   

11.
Twenty-four early-weaned pigs were fed three different rations, with and without the addition of 16 mg. iodinated casein/lb. feed. In general, supplementation did not result in any change in liveweight gain, feed intake or feed efficiency, but brought about a noticeable, though not statistically significant, increase in the apparent digestibility of dry matter, gross energy, crude protein, ether extract, and total carbohydrates. An examination of the results of supplementing individual rations revealed that in one case iodinated casein had adversely affected liveweight gain, feed intake and efficiency of feed conversion. This particular ration, in comparison with the other two feeds, contained a high level of soybean oilmeal and a low level of feed of animal origin.  相似文献   

12.
The ban of antibiotics as a feed additive requires alternatives to stabilize the health and performance particularly of the young animals. Essential oils obtained from fennel seed (Foeniculi aetheroleum) and caraway seed (Carvi aetheroleum) were tested in diets for weaned piglets in comparison with either a diet without feed additive or with a combination of formic acid and copper (positive control). Four groups of sixteen piglets (live weight 7 kg, age 26 days) received diets without (1) or with supplements of 7.5 g formic acid + 160 mg Cu/kg (2), 100 mg fennel oil/kg (3) or 100 mg caraway oil/kg (4) during 3 weeks after weaning. In the subsequent 4 weeks, all piglets were fed a diet without these additions. Fennel oil contained almost 2/3 anethol, approximately 1/5 fenchon and the remaining part consisting of alpha + beta-pinen, limonen (p-mentha-1,8-dien) and estragol. In the caraway oil, half of the contents was represented by limonen and the other half by carvon. There were no piglet losses and only few cases of diarrhoea. The combination of formic acid and copper increased feed consumption by 27% and daily weight gain by 25%. There were no differences in the performance between the group fed fennel oil and the control without additives. Piglets fed caraway oil tended to consume less feed and to gain approximately 10% less. In feed choice experiments, pigs consumed the same two diets from two troughs with 50% of total feed amount, as expected. The diets containing fennel or caraway oils were consumed at less than 50%. If the diet contained 100 mg fennel oil/kg, the decrease of percentual feed intake was significant. The results of the feeding experiment and of the feed choice experiment question the classification of fennel and caraway oils as flavour additives or as 'appetite promoters' in diets for weaned piglets.  相似文献   

13.
Broiler chicks were fed on a commercial‐type ration containing 20 g oxy‐carotenoids/ton for 5 weeks, half receiving 0.005% roxarsone. All birds were then fed on finisher rations containing a moderate (20 g/ton) to high level (40 g/ton) of oxycarotenoids from food ingredients alone and in combination with 2 and 4 g canthaxanthin/ton for 26 d. The birds given roxarsone in the starter ration also received 0.005% roxarsone in the finisher ration together with the above‐listed oxycarotenoid supplements. Roxarsone was withdrawn from the ration 5 d prior to termination of the study to simulate commercial requirements.

The continuous feeding of 0.005% roxarsone had no effect on weight gain, food conversion or pigmentation as assessed by visual shank scores, using the Roche Yolk Color Fan, and colorimetric assay of total carotenoid concentrations in plasma, toe‐web skin and shank skin. Shank visual scores reflected the increased levels of oxycarotenoids derived from food ingredients alone and the effect of supplemental canthaxanthin. These data show that canthaxanthin is an effective pigmenter adjuvant, when added at 2 to 4 g/ton to rations containing 20 to 40 g of oxy‐carotenoids/ton from food ingredient sources. Concurrent feeding of 0.005% roxarsone, while having no positive effect on pigmentation, had no adverse effect on the pigmenting properties of canthaxanthin.  相似文献   


14.
Experiments were conducted with growing crossbred chicks to determine the reasons why cysteine exacerbates roxarsone (3-nitro-4-hydroxyphenylarsonic acid) toxicity. A fortified corn-soybean meal diet that met or exceeded all nutrient requirements of the young chick was fed. While cysteine enhanced roxarsone toxicity, it had little effect on the toxicity of the inorganic arsenicals As2O3 and As2O5. The toxicity of another pentavalent organic arsenical, phenylarsonic acid, was also exacerbated by cysteine. In contrast, the growth-depression resulting from feeding the trivalent form of phenylarsonic acid, i.e., phenylarsine oxide, was not affected by dietary addition of cysteine. Supplementation of the diet with cystine, methionine or K2SO4 did not exacerbate roxarsone toxicity. Reduced glutathione (GSH), however, slightly increased the gain/feed depression resulting from feeding 300 mg roxarsone/kg diet. When injected ip 1) roxarsone and cysteine, or 2) roxarsone and ascorbic acid killed 100 or 60% of the birds, respectively, within 48 h postinjection. Few (6.7%) deaths resulted from ip injections of the same level of roxarsone alone. Therefore, the potentiation of toxicity requires pentavalent organic arsenicals and compounds that can act as reducing agents. We concluded that cysteine exacerbates roxarsone toxicity by reducing it to the more toxic trivalent state.  相似文献   

15.
The 21 field isolates of Treponema hyodysenteriae which were tested were sensitive to 3-acetyl-4'-isovaleryl tylosin (AIV); the minimal inhibitory concentration was 0.25 to 16 micrograms/ml. 3-Acetyl-4'-isovaleryl tylosin administered prophylactically to pigs at concentrations of 5 to 100 mg/kg of feed and tylosin at 110 mg/kg of feed for 28 or 31 days prevented swine dysentery induced by tylosin-sensitive T hyodysenteriae strain SQ2; 15 nonmedicated, inoculated control pigs had bloody diarrhea, and 9 pigs died. In 2 additional trials, AIV administered prophylactically for 28 days at 55 or 110 mg/kg of feed prevented swine dysentery induced by tylosin-insensitive T hyodysenteriae strain B204. All of the inoculated principal pigs medicated with AIV at 55 or 110 mg/kg of feed or carbadox at 55 mg/kg of feed and the noninoculated sentinel pigs for each group had solid feces throughout the 56-day trial. In the nonmedicated, inoculated control groups, bloody diarrhea began at 4 to 5 days after inoculation was done, and 9 of 10 principal pigs and 6 of 9 sentinel pigs had dysentery; 2 pigs died. In the groups medicated with AIV at 27.5 or 5.5 mg/kg of feed, all 5 principal pigs and 3 or 4 sentinel pigs in each group had dysentery; 3 or 4 pigs in each group died. In the group medicated with tylosin at 110 mg/kg of feed, 7 of 10 principal pigs and all 9 sentinel pigs had dysentery; 1 pig died.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

16.
In order to guarantee an equally good development of ileorectostomized pigs (IRA) used for the determination of precaecal protein digestibility and the absorption of amino acids as for intact animals (INT), the supplementation of their rations with easily soluble carbohydrates and minerals is necessary. The effects of these supplements on live weight development, nitrogen balance and N utilization level were the subject of the assessment of 21 rations with 129 and 117 balance measuring resp. with growing IRA and INT pigs. Without any supplementation of the rations the N balances of the IRA pigs showed significantly lower and partly negative N balances and N utilization levels in comparison to the INT pigs. The combined supplement of easily soluble carbohydrates (100 g/kg DM intake) and 300 ... 400 ml electrolyte solution per day (approximately 1 ... 1.3 g additional Na) resulted in N balances almost equal to those of INT pigs. The supplement of both electrolyte solution and NaHCO3 (approximately 2 g Na per animal and day additionally) to a barley + lysine ration resulted in a significant increase of the N balance and N utilization in IRA pigs of a live weight between 120 and 140 kg in contrast to the control period. A supplement of carbohydrates to a ration consisting of barley + fish meal + grass meal and electrolyte supplements of 400 ml per animal and day only resulted in significantly higher N balances and N utilization levels in the live weight range up to 70 kg in comparison to the control periods, which then corresponded to those of INT pigs. There was no essential influence of carbohydrate supplementations on pigs of more than 70 kg live weight. The postileal digestibility of the crude carbohydrates (CC) of 14 rations calculated from the difference between total digestibility (faecal analysis) and precaecal digestibility (analysis of the ileal chyme of IRA pigs) showed that between 40 and 100 g (70 g on average) out of the 780 g CC per kg DM consumed disappear in the large intestine. These studies show that in the testing of concentrates and mixed feed rations the supplementation of 100 g easily soluble carbohydrates/kg DM intake should be sufficient to guarantee a normal development of IRA pigs. In addition, an oral supply of 1 to 2 g sodium in the form of electrolyte solution exceeding the requirement of INT pigs is necessary as this supplementation significantly improves the N retention of IRA pigs even heavier than 100 kg.  相似文献   

17.
The interaction between 3-nitro-4-hydroxyphenylarsonic acid (roxarsone) and Cu was studied in a series of experiments with crossbred, broiler-type chicks. A fully fortified corn-soybean meal diet was fed in all assays. While roxarsone caused a marked reduction in liver Cu concentration, arsanilic acid (4-aminophenylarsonic acid), As2O3 and As2O5 were without effect. When structural analogs of roxarsone were studied, it was found that o-nitrophenol and 3-nitro-4-hydroxybenzoic acid also had no effect on liver Cu concentration in birds fed a high level of Cu. However, liver Co concentration was reduced by the addition of either o-nitrophenol or roxarsone to the diets of birds fed a high level of Co. It was concluded that arsenic per se had no effect on liver Cu accumulation or depletion, but that a chelate was probably formed between Cu or Co and the nitroso and hydroxyl groups of the ring portion of roxarsone. In addition to the reduction in liver Cu deposition, concentrations of Cu in the bile, brain, heart and pancreas of chicks were reduced by the addition of roxarsone to a high-Cu diet. Neither dietary nor intraperitoneally (ip) injected roxarsone had an effect on liver Cu concentration when Cu was injected ip. Therefore, both roxarsone and Cu had to be present in the diet for the liver Cu-lowering effect of roxarsone to be exerted. A further experiment was conducted with growing rats to determine the effect of roxarsone on Cu balance. Feeding roxarsone elevated Cu excretion in the urine but had no effect on Cu excretion in the feces.  相似文献   

18.
An experiment with five litter-mate barrows showed that severe reduction in feed intake and growth rate accompanied the inclusion of either 1.0 or 2.0% ergot in the ration. Levels of 0.10 and 0.05% ergot allowed moderate feed intake and weight gain but not equal to the pig fed the ergot-free ration. A subsequent experiment involving five lots of four litter-mate barrows each, indicated the possibility of reduced feed intake and growth performance by growing-finishing pigs fed rations containing 0.05 — 0.10% ergot. This was substantiated by a N-balance experiment in which control pigs retained 1.54 gm more N daily than pigs fed 0.10% ergot. The total alkaloid content of the ergot used in these experiments was 0.292%; the predominant alkaloid (71%) being ergocristine.  相似文献   

19.
There is concern that therapeutic use of zinc oxide (ZnO) in swine production may select for methicillin‐resistant Staphylococcus aureus (MRSA) due to co‐location of the zinc resistance gene (czrC) and methicillin resistance gene (mecA) within the staphylococcal cassette chromosome mec (SCCmec). The objective of this investigation was to determine whether MRSA carriage in pigs is influenced by exposure to therapeutic doses of in‐feed ZnO (3000 mg/kg) when compared to the recommended dietary levels (100 mg/kg). A randomized controlled trial was completed using 110 pigs that were naturally colonized with czrC‐positive MRSA. The pigs were followed from birth to weaning (21 d), at which point they were randomized into 8 pens and exposed to either a control feed (100 mg ZnO/kg feed; n = 49 pigs) or a treatment feed (3000 mg ZnO/kg feed; n = 50 pigs); neither feed contained additional antimicrobials. MRSA carriage was monitored weekly in each group for 4 weeks post‐weaning. The prevalence of MRSA was significantly higher in the treatment group at 1‐week (OR = 18.1; P < 0.01) and 2 weeks (OR = 3.01; P = 0.01) post‐weaning when compared to the control group, but there was no difference later in the nursery phase. Persistent MRSA carriage (testing positive ≥2 times post‐weaning) was observed in 2% (1/49) of control pigs and 22% (11/50) of treated pigs (P < 0.01). All MRSA isolates (spa types t034 and t3075) carried czrC and showed uniform resistance to zinc. These findings demonstrate that the prevalence and persistence of MRSA in nursery pigs can be affected by high levels of in‐feed ZnO in the absence of antibiotics.  相似文献   

20.
For the purpose of ascertaining the vitamin A requirement seven experiments with 303 pigs in the live weight range between 6.5 and 114 kg were made. In three experiments under in practice conditions we checked the standard vitamin A supplement to the mixed feed with 1,732 pigs (live weight range between 8.5 and 110 kg). The supplement to vitamin-A-free rations and to those poor in or free of carotene amounted to between 0 and 8,000 IU/kg feed. Above that, between 0 and 16 mg beta-carotene and 1,000 mg nitrite/kg feed were supplemented. As long as the vitamin A store in the liver during weaning amounted to greater than 50 IU and greater than 100 IU/g at the beginning of fattening, feed intake, live weight growth and feed expenditure were not influenced by the supplement of vitamin and provitamin resp. The supplement of 250 IU resulted in the same weight growth from weaning to the end of fattening as that of 4,000 IU. Nitrite supplement had a negative effect at 250 IU, at 500 IU vitamin A consumption and weight growth tended to be only insignificantly lower. The methaemoglobin content decreasing in the course of the experiment reflects the adaptation of the pigs to the nitrite load. The consumption and growth depression caused by vitamin A deficiency could be observed from the 7th week of the experiment when casein-swelling starch rations were fed, but from the 13th week of the experiment only when cereal-soybean oilmeal rations were fed. The weight of liver, spleen, kidneys, heart and brain was not influenced by vitamin A supply. The same applies to the body composition and retention with the exception of two deficiency piglets, which contained less fat in the empty body than the control animals.  相似文献   

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