饲喂全株玉米青贮及额外补充碳酸氢钠对疆岳驴生长性能、消化率、血清生化指标及经济效益的影响

试验旨在研究饲粮中两种全株玉米青贮比例及额外补充碳酸氢钠对疆岳驴生长性能、营养物质表观消化率、血清生化指标及经济效益的影响。选取体况良好的6~8月龄疆岳驴断奶公驴40头（106.02 kg±11.81 kg）,随机分为5组：全株玉米青贮占粗饲料的比例分别为0（Ⅰ组）、30%（Ⅱ组）、60%（Ⅲ组）及额外补充碳酸氢钠的Ⅳ组（全株玉米青贮占粗饲料30%+碳酸氢钠）和Ⅴ组（全株玉米青贮占粗饲料60%+碳酸氢钠）,碳酸氢钠正常添加量按照精料干物质的0.5%计算,额外添加量按照精料干物质的0.5%+全株玉米青贮干物质的1%计算,每组8头驴,按照等能等氮原则设计饲粮。预饲期12 d,正试期120 d。结果显示,随着全株玉米青贮添加量的增加,试验Ⅰ、Ⅱ和Ⅲ组料重比逐渐下降,其中试验Ⅲ组显著低于试验Ⅰ、Ⅱ组（P<0.05）;试验Ⅲ组粗脂肪、中性洗涤纤维、粗灰分的表观消化率最高,显著高于试验Ⅱ组（P<0.05）,总蛋白、肌酐含量和碱性磷酸酶活性均显著高于试验Ⅰ组（P<0.05）,试验Ⅲ组葡萄糖含量极显著低于试验Ⅰ组（P<0.01）,试验Ⅲ组总胆固醇含量显著低于试验Ⅰ、Ⅱ组（P<0.05）。与同等比例添加全珠玉米青贮的组相比,试验Ⅱ组平均日增重显著高于试验Ⅳ组（P<0.05）,试验Ⅲ组平均日增重高于试验Ⅴ组（P>0.05）;试验Ⅲ组料重比显著低于试验Ⅴ组（P<0.05）,试验Ⅱ组料重比低于试验Ⅳ组（P>0.05）;试验Ⅱ、Ⅳ组间粗蛋白质、粗脂肪、能量和粗灰分的表观消化率差异均不显著（P>0.05）;试验Ⅲ、Ⅴ组营养物质的表观消化率差异均不显著（P>0.05）;试验Ⅳ组总胆固醇含量及谷丙转氨酶活力均显著高于试验Ⅱ组（P<0.05）。试验Ⅰ~Ⅴ组疆岳驴每千克增重成本分别为16.40、15.10、14.79、17.34和16.10元,整个试验期每头驴毛利润分别为711.27、837.53、871.98、629.46和738.16元。综上,在本试验条件下,以生长性能、营养物质表观消化率及血清生化指标为评价依据,综合经济效益比较,以在基础饲粮（以DM为基础）中添加0.28%碳酸氢钠时、全贮玉米青贮占粗饲料60%（在基础饲粮DM中添加26.67%）饲喂疆岳驴公驴效果最优,无需额外补充碳酸氢钠。     

Prolactin,Androstenedione and IGF1 Serum Concentrations During Induced Follicular Growth by eCG Administration in the Bitch

The oestrus cycle in the domestic bitch, a monoestrous species, differs considerably from that of other veterinary domestic animals species. In the bitch the combined use of eCG and hCG is effective to induce oestrus predictably and safely (Stornelli et al., Theriogenology, 78, 2012 and 1056). Although several studies were done to describe the hormonal changes during the canine oestrus cycle, to our knowledge none was done to describe the hormonal changes during induced follicular growth after the administration of eCG. The aim of this work was to study prolactin (PRL), insulin‐like growth factor (IGF1) and androstenedione (ANDR) serum concentrations during follicular growth induced by a single dose of eCG administered to late anoestrous bitches. PRL and ANDR concentrations were lower before than after eCG TRT (before eCG vs pro‐oestrus, oestrus and dioestrus; 4.3 ± 1.8 ng/ml vs 6.5 ± 1.6 ng/ml, p < 0.05; 0.08 ± 0.2 ng/ml vs 0.42 ± 0.16 ng/ml, p < 0.05). Conversely, IGF1 concentrations were similar before and after eCG TRT (286.0 ng/ml ±32.2, p > 0.53). Additionally, PRL concentrations were similar before oestrus compared to during oestrus and dioestrus (6.9 ± 1.7 ng/ml, p > 0.19). Furthermore, IGF1 concentrations were higher before and during oestrus compared to first day of dioestrus (286.1 ± 29.8vs 200.4 ± 29.2 ng/ml, p < 0.01). On the contrary, ANDR concentrations were lower before and during oestrus compared to first day of diestrum (0.35 ± 0.17 ng/ml and 0.38 ± 0.15 vs 0.68 ± 0.17 ng/ml, p < 0.05). These results show that treatment with a single injection of 50 IU/kg of eCG in late anoestrous bitches successfully induced changes in follicular growth which were paralleled with changes in PRL, IGF1 and ANDR serum concentration similar to those occurring during a normally occurring oestrous cycle. In addition, our results suggest that IGF1 in the bitch could play an important role in ovarian folliculogenesis.     

Some Effects of a Low Sodium Diet High in Potassium on the Renin-Angiotensin System and Plasma Electrolyte Concentrations in Normal Dogs

Pedersen, H.D., J. Koch, A.L. Jensen, K. Poulsen, A. Flagstad: Some effects of a low sodium diet high in potassium on the renin-angiotensin system and plasma electolyte concentrations in normal dogs. Acta vet. scand. 1994, 35, 133-140. - Eight normal male Beagle dogs received 0.7 mmol Na⁺/kg/day for 5 weeks and 4.0 mmol Na⁺/kg/day in one 3 week control period preceding and another similar period following the low sodium period. The dogs received 6.8 mmol K⁺/kg/day throughout the study.The median plasma renin activity (PRA) and plasma aldosterone concentration (PAC) were higher in the low sodium period than in the following control period (0.67 versus 0.28 ng/ml/h, p < 0.0001) and (204 versus 31 pg/ml, p < 0.0001). PRA and PAC quickly stabilized on a new steady level in response to altered intake of sodium chloride. The angiotensin-converting enzyme (ACE) activity was not changed by the altered intake of sodium chloride.The plasma concentrations of sodium and chloride were increased during the low sodium period. This could be due to an indirect effect of the high potassium intake of the dogs. Potassium leads to an increased secretion of aldosterone and thereby to an increased retention of sodium and chloride in the kidney. The possible implications of a high potassium content in a low sodium diet are discussed.     

Correlation Between Serum Activity of Muscle Enzymes and Stage of the Estrous Cycle in Italian Standardbred Horses Susceptible to Exertional Rhabdomyolysis

Equine exertional rhabdomyolysis (ER) is a well-recognized clinical syndrome affecting racehorses. Prevalence analysis of ER showed that female sex was a significant risk factor. The aim of this research was to evaluate the differences and correlations in the serum activity of muscle enzymes and the stage of the estrous cycle in ER-susceptible and control (C) mares. Serum muscle enzyme activity before and after exercise and sex hormones were analyzed in the two groups of mares. Ten cyclic ER and 10 cyclic C mares were examined weekly for 4 weeks. During diestrus, ER horses had significantly higher resting and postexercise aspartate aminotransferase (AST) activity, but not creatine kinase (CK) activity, compared with controls; only postexercise AST activity was significantly higher during estrus compared with activity levels in controls. During estrus, 17β-estradiol and AST activity were significantly negatively correlated in the control but not ER mares. Based on our results, further studies should be performed to characterize the presumptive different roles played by sexual hormones in horses susceptible to ER compared with healthy mares.     

A Comparison of the Plasma Fructose Concentrations in Dogs and Cats and Changes in the Fructose Concentrations in Dogs Following Intravenous Administration of Fructose

The plasma concentrations of fructose, glucose, free fatty acids (FFA) and triglycerides (TG) were measured in dogs and cats. Changes in these concentrations were investigated in dogs by an intravenous fructose tolerance test (IVFTT) at a dose of 0.1 g/kg body weight. Fructose concentrations in the plasma of dogs were significantly higher than those of cats. There was no significant difference in plasma glucose concentrations between dogs and cats. Plasma FFA concentrations decreased and TG concentrations increased after feeding in both dogs and cats. During the IVFTT, the plasma fructose concentrations in the dogs increased rapidly to a peak by 2 min and then decreased to half of the peak by 5 min after the administration of fructose. Administration of fructose resulted in an increase in the plasma TG concentrations and reduced plasma FFA concentrations in the dogs. Only 4% of the administered fructose was detected in the urine of dogs following IVFTT. Plasma fructose was considered to be rapidly absorbed and metabolized in both dogs and cats. However, as with glucose metabolism, there appear to be some differences in fructose metabolism between dogs and cats.     

Electromyoenterography During Normal Gastro-Intestinal Activity, Painful or Non-painful Colic and Morphine Analgesia, in the Horse

The electrical potentials were recorded from the antrum, the duodenum, the ileum and the first part of the colon of ponies under (a) normal resting conditions, (b) during nonpainful colic and (c) after intravenous morphine administration.

The normal pony, at rest, had five contractions of the antrum per minute. On the small intestine, the basal electrical activity decreased from the duodenum (14-15/min) to the ileum (10-11/min). The small bowel also had three types of motility: peristaltic waves, rhythmic segmentations and random contractions. On the colon, bursts of potentials indicating intense motor activity occurred at the rate of 20 to 30 per hour. Morphine given intravenously (IV) greatly increased the frequency of the electrical potentials of the antrum and the longitudinal bands of the colon.

During non-painful colic, hyperactivity of the cranial small intestine was continuous. Spasms of the jejunum occurred every minute and could not be relieved by morphine (IV).

When colic was painful, jejunal spasms announced the crisis of intense abdominal pain. After morphine (IV) the spasms and pain disappeared; the jejunum remained hyperactive, the motility of the colon was increased while the antrum became quiet.

     

Adrenocortical Interactions following Dehydration, Sodium chloride, Potassium chloride, Cortisone acetate and Desoxycorticosterone acetate Treatments in the Parakeet, Quail and Myna

Dehydration results in an extreme hypertrophy and hyperplasia of the adrenocortical tissue, whereas NaCl produces a profound atrophic change. KCl brings the gland to some hypertrophy in parakeet and myna, but to some atrophy in quail. The response to cortisone and desoxycorticosterone acetate clearly indicates an atrophic look in quail and myna, however, in parakeet both the subcapsular and the central zones respond uniformly towards hypertrophy. No specific zonal responses could be detected even in cases with a histomorphological zonation. This may be due to the hormonal situation discussed by other authors.     

Effects of Triiodothyronine-induced Hyperthyroidism on Lipid Peroxidation,Erythrocyte Resistance and Iron-binding and Iron-oxidizing Antioxidant Properties of Plasma in the Rabbit

The effect of hyperthyroidism on some oxidative stress parameters is reported. The hyperthyroid state was induced by intraperitoneal injection of triiodothyronine (T₃)(10 μg/kg body weight) for 14 days in two groups of female rabbits (3 and 12 months old). The T₃ injection caused increase by 1.5-fold to 1.7-fold in T₃ serum level, and 2-fold to 3-fold decrease (age-dependent) in body weight gain at the end of experimental period. The induced hyperthyroidism caused a significant increase in the serum concentration of the lipid peroxidation end-product malondialdehyde and lowered erythrocyte resistance to oxidative stress when subjected to the free radical generator 2,2'-azobis(2-amidinopropane) hydrochloride in vitro. The half maximum haemolysis time (HT₅₀) decreased in the both experimental groups of rabbits, by about 12 min in the 3-month-old animals and 27 min in the 12-month-old animals. The study showed for the first time that hyperthyroidism enhances the ability of plasma to protect against iron-binding and iron oxidizing organic radicals. The scavenging property and antioxidant capacity of plasma against iron-binding inorganic radicals also increased. Measurement of erythrocyte resistance to oxidative stress and the protective ability of plasma against oxygen radicals discriminates the thyroid hormone modulatory effects in defence mechanisms against lipid peroxidation.     

Body Weight,Carcass Yield,and Intestinal Contents of Broilers Having Sodium and Potassium Salts in the Drinking Water Twenty-Four Hours Before Processing

The purpose of this study was to investigate the effects of drinking water supplementation with graded increases of Na and K salts on the performance and gut contents of broilers before processing. Birds had no water, tap water, or water supplemented with sodium bicarbonate or potassium chloride in the concentrations of 0.15, 0.30, and 0.45% in the last 12 and 24 h before processing. The last 12 h coincided with preslaughter feed withdrawal. Cobb × Cobb 500 male broilers (46 d old) were set in a completely randomized experimental design with 8 treatments and 9 replications of 9 birds each. Birds were individually processed within a period of 12 h of feed withdrawal every 2 h. Individual weighing was followed with electrical stunning and removal of intestinal contents of the upper (crop through the gizzard) and lower segment (duodenum through cloaca). Water intake increased linearly with greater salt concentrations in the water (P < 0.05). Body weight loss increased linearly through the feed withdrawal; however, it was greater with birds without water access (P < 0.0001). There were no effects of treatments on the yields of carcass and cuts as well as on the intestinal contents at all evaluated times. Intestinal contents from upper and lower segments were decreased with time, but responses to the water treatments were not observed (P > 0.05). It is concluded that increasing water intake through the use of Na and K salts did not affect the rate of gut emptying before processing.     

罗伊氏乳酸杆菌LR1对猪蛋白消化酶基因表达、肌肉抗氧化指标及氨基酸组成的影响

试验旨在研究长期饲喂罗伊氏乳酸杆菌LR1（Lactobacillus reuteri 1）对猪胃及胰腺蛋白消化相关酶的基因表达、肌肉抗氧化指标及冰鲜肉氨基酸谱的影响。选用144头（杜×长×大）21日龄断奶仔猪（平均体重6.49 kg±0.04 kg）,随机分为3组。对照组饲粮为基础饲粮,抗生素组饲粮为添加抗生素的基础饲粮（仔猪阶段添加100 mg/kg喹乙醇和75 mg/kg金霉素,生长肥育猪阶段添加75 mg/kg金霉素）,LR1组饲粮为添加5×10¹⁰ CFU/kg LR1的基础饲粮,试验期175 d。结果表明：与对照组相比,①抗生素组猪胰腺中弹性蛋白酶的表达降低（P<0.05）;LR1组胃窦、胃贲门及胃底黏膜中胃蛋白酶A的表达提高（P<0.05）,同时也高于抗生素组（P<0.05）。②抗生素组猪背最长肌（longissimus dorsis muscle,LDM）总抗氧化能力（total antioxidant capacity,T-AOC）及总超氧化物歧化酶（total superoxide dismutase,T-SOD）活力增加（P<0.05）;LR1不影响LDM中丙二醛（malondialdehyde,MDA）含量,T-AOC、T-SOD及谷胱甘肽过氧化物酶（glutathione peroxidase,GSH-Px）活力（P>0.05）。③饲粮添加抗生素及LR1不影响冰鲜肉水解氨基酸含量及组成（P>0.05）;抗生素组24 h冰鲜肉中甲硫氨酸（苦味氨基酸）含量、甜味氨基酸总量及游离氨基酸总量降低（P<0.05）,而LR1降低24 h冰鲜肉中甲硫氨酸含量（P<0.05）;饲粮中添加抗生素及LR1均降低48 h冰鲜肉中甜味氨基酸、苦味氨基酸、必需氨基酸及总游离氨基酸（P<0.05）,同时,抗生素组48 h冰鲜肉中鲜味氨基酸含量降低（P<0.05）。综上,与对照组相比,长期饲喂LR1可提高猪胃对蛋白质的消化功能,改善24 h冰鲜肉的风味;而长期饲喂抗生素降低猪胰腺的消化功能,提高肌肉抗氧化能力,但降低24及48 h冰鲜肉的风味。     

Differences between Plasma and Serum Samples for the Evaluation of Blood Chemistry Values in Rainbow Trout,Channel Catfish,Hybrid Tilapias,and Hybrid Striped Bass

Abstract

Blood chemistry analytes are determined for fish from either serum or plasma samples. Serum and plasma are similar in that they both represent the fluid component of blood; however, plasma contains clotting factors that are not present in serum. This study was conducted to determine whether the type of sample—plasma or serum—had an effect on measured blood analytes in rainbow trout Oncorhynchus mykiss, channel catfish Ictalurus punctatus, hybrid tilapia Oreochromis spp., and hybrid striped bass (striped bass Morone saxatilis × white bass M. chrysops). Paired plasma and serum samples were analyzed for the following standard biochemical analytes: total protein, albumin, globulin, creatinine, total bilirubin, alkaline phosphatase, aspartate aminotransferase, sodium, potassium, chloride, calcium magnesium, phosphorus, glucose, and cholesterol. For all four taxa, values for potassium were lower in the serum and magnesium and phosphorus values were higher in the serum. Glucose values were lower in the serum from rainbow trout, hybrid striped bass, and channel catfish; whereas cholesterol values were higher in the serum of rainbow trout, channel catfish, and hybrid tilapias. The differences observed between serum and plasma were distinct from changes occurring with hemolysis and, therefore, do not represent release of erythrocyte constituents. The differences most likely represent metabolic utilization of blood constituents while the blood was clotting. This work indicates that plasma should be used preferentially to serum for biochemical analysis because analyte levels determined from serum may not accurately reflect those found in circulating blood.     

不同季节肉用种公牛精液品质与生理常值、血清及精清生化指标相关关系研究

以利木赞和夏洛来种公牛为试验牛，研究不同季节对其精液品质、冻精产量、生理常值、血清及精清生化指标的影响。结果表明：（1）与其它季节相比，夏季肉用种公牛的原精活力、冻精活力、活精于百分数、顶体完整率均显著降低，而精于畸形率显著升高（P〈0．05）。精子密度以秋季最低。（2）冻精产量夏季处于最低水平，平均每月仅为7388支。（3）夏季肉用种公牛的血清LH、睾酮、T3、皮质醇的含量分别为48．12、4．15、1．11、4．89ng／L，显著低于春、秋、冬季（P〈0．01）。（4）夏季肉用种公牛血清钠、钾、钙、镁均处于最低水平，显著低于其它季节（P〈0．01）。（5）夏季肉用种公牛精清睾酮水平明显下降，显著低于春季、秋季和冬季。（6）精清钠、钾、钙夏季含量最低，分别为83．12mmol／L、18，77mmol／L和4．63mmol／L；精清镁含量由春季至秋季呈显著下降趋势；精清磷含量夏季最高，为4．65mmol／L，显著高于春季、秋季和冬季。（7）肉用种公牛精清ALP夏季含量为1784．3U／L，显著高于春、秋两季，但低于冬季。（8）精清睾酮与精液品质各指标存在显著相关；血清生化指标与精清生化指标存在显著相关；直肠温度、呼吸频率与精液品质及血清生化指标存在显著相关性，与精清生化指标相关性不大。     

Changes in Serum Magnesium Levels of Ruminants,as Influenced by Abrupt Changes in the Composition of the Diet Effect of Oral Administration of Various Inorganic and Organic Compounds on the Serum-Magnesium Level

During a period of four years in succession samples of grass from tetany prone pastures, topdressed with large amounts of amraon-sulphate and potassiumsulphate, have been analysed throughout the tetany season each year, and the results have been compared with the analytical data obtained from corresponding samples of grass collected from normally dressed pastures. The content of Mg and Ca and the feed unit value of the tetany prone grass differed very little from the normal. The protein content, however, was exceptionally high, and rather great differences were found in the content of P, S, K, Na and the trace elements. Several feeding experiments have been carried out in order to test the hypomagnesaemic and/or the tetanygenic effect of these compounds as dietary supplements to ruminants. The feeding was performed under exact daily control and the experiments were supported by daily serum mineral analyses. Experiments carried out with diets containing protein and feed units in the same ratio as found in the highly topdressed pasture grass, proved that this unbalanced ratio undoubtedly played an important role in the hypomagnesaemia inducing effect of the grass. As long as the fodder was given in amounts high enough to cover the feed units requirements, the level of serum Mg remained unchanged. The falling tendency of the serum Mg level was, however, evident when the fodder rations were reduced to amounts insufficient to cover the feed unit requirements ot the cows — a situation often met with for shorter periods during pasturing. Hypomagnesaemia was produced within 3–4 days, whereas a similar reduction of a normally balanced fodder to cows had no serum Mg reducing effect in the course of twelve days.Of other factors coming into play, especially K₂HPO₄, Na₂HPO₄, K₂SO₄ and Na₂SO₄ proved to influence the serum mineral balance. Oral applications of large doses of these substances to healthy sheep, produced neither pronounced hypomagnesaemia nor tetany. The initial drop in the levels of serum Mg and particularly serum Ca were, however, so remarkable that tetany very probably would have been provoked if the animals had been in a hypomagnesaemic state when the experiment started.Experiments and results have been closely discussed. The conclusion has been drawn that the tetany prone effect of the heavily ammonsulphate dressed pastures could not possibly be conditioned by one single factor in the grass. A more possible explanation seems to be an unpropitious interaction of more active compounds present at the same time:The first step in the development of the disorder, i. e. the hypomagnesaemic condition, seems principally to be due to the unproportionately high content of protein in relation to the feed unit value of the grass. Owing to the fact that the quantity of dietary protein is in excess even if the feed unit content does not cover the theoretical requirements, the milk production remains high and the cows are hampered in their efforts to accomodate to those reductions in food intake unevitably happening to occur on pasture. The next step, the convulsion of tetany, however, depends upon other, co-operating factors able to disturb the Ca-balance at the very moment when the serum Mg is already low. According to the serum Mg- and Ca-reducing effect brought about by diets supplemented with alkaliphosphates and -sulphates, the author incline to the view that the extremely high content of P, S, K and to some extent also of Na found in the tetany prone pasture grass, may be the background for this effect of the grass. Temperature, rainfall and other environmental factors have also been taken into consideration as influencing the appetite and the absorptioncoefficient.