Some diagnostic features of the pathogenesis of bovine paratuberculosis (Johne's disease) and serum biochemical changes after oral reinfection

Ten bull-calves were infected with 10(8) viable cells of Mycobacterium paratuberculosis per os. During the 400-day period of observation faecal and blood samples were taken from animals at 30-day intervals. Faecal samples were examined microscopically, blood samples by the CFT, AGID and LST tests. Intradermal allergic tests were carried out at PI (post infection) days 92, 217, 336, using mammalian, avian and johnin PPD. In the period of study, these efficiency indices showed fluctuations characteristic of the given tests. In the period between PI day 160 and 400 fifteen biochemical parameters were measured monthly, TRP, ALP, TRIG and CHOL were reduced by day 400, pointing to disorders of digestion and absorption. Increased activities of CK, ALD, LDH, alpha-HBDH and ALT indicated skeletal muscle and/or liver damage in the first place. Serum CK, ALD activities and TRIG and TRP concentrations may serve as useful complementary values to the specific diagnosis of paratuberculosis, particularly in the advanced stage of the disease.     

引入西藏高原的家兔血液生化参数的比较研究

对引入西藏高原多年的加利福尼亚兔和中国白兔的12项血清生化指标进行测定,并与SPF新西兰兔进行比较。结果显示：①3个品种公兔之间,加尼福利亚兔与中国白兔比较,AST、TP、ALB、GLO、A／G、GLU、CRE、LDH差异极显著（P〈0．01）,TG、BUN差异显著（P〈0．05）,其中TP、ALB、A／G、CRE、CHOL、LDH表现极强的公兔特征,而ALT、GLU母兔明显高于公兔;加利福尼亚兔与SPF新西兰兔比较。ALT、A／G、CRE、TG、BUN差异显著（P〈0．05）,AST、CHOL、LDH差异极显著（P〈0．01）;中国白兔与SPF新西兰兔比较,ALT、AST、TP、ALB、GLO、A／G、CRE、CHOL、TG差异极显著（P〈0．01）;②3个品种母兔之间,加利福尼亚兔与中国白兔比较,ALT、GLO、CRE、TG差异显著（P〈0．05）,AST、TP、BUN、LDH差异极显著（P〈0．01）,加利福尼亚兔与SPF新西兰兔比较,ALT、TP、ALB、GLO、A／G、BUN、CRE、LDH差异极显著（P〈0．01）,AST、TG差异显著（P〈0．05）;中国白兔与SPF新西兰兔比较,ALT、TP、ALB、GLO、A／G、CRE、CHOL、TG、LDH差异极显著（P〈0．01）,BUN、AST差异显著（P〈0．05）。     

Effect of storage on some constituents of camel serum

SUMMARY Effects of storage at room temperature (23–25°C) and refrigeration (4–5°C) on various biochemical constituents of camel serum were investigated. Albumin, globulin, calcium, phosphorus, cholesterol, aspartate aminotransferase (AST), alkaline phosphatase (AP) and gamma glutamyltransferase (GGT) did not change over 9 days when stored at 4–5°C. At 4–5°C, creatinine, iron and glucose in camel sera remained stable for 6 days; total protein for 7 days; and blood urea nitrogen for 8 days. Decreased activities in creatine kinase (CK), lactate dehydrogenase (LDH) and alanine aminotransferase (ALT) were apparent after 1, 6 and 7 days, respectively. At room temperature, total protein, albumin, globulin, calcium and phosphorus were stable throughout the 9 days. Changes in glucose and iron occurred after 3 days. Stability at room temperature for LDH was 1 day; AST, 3 days; GGT and ALT, 6 days; and AP, 8 days. CK activity had already declined by 4 hours and by 9 days, only 34% activity remained.     

Effect of acepromazine on the signs of capture stress in captive and free-ranging roe deer (Capreolus capreolus)

The differences between the capture stress responses of captive and free-ranging roe deer (Capreolus capreolus) and their modulation by acepromazine, during a period of three hours' physical restraint after capture in drive-nets, were examined in 16 free-ranging and 16 captive roe deer. Eight of the free-ranging and eight of the captive animals received acepromazine intramuscularly, and the other eight free-ranging and eight captive deer received the same volume of saline. Heart rate, body temperature and haematological and serum biochemical parameters were analysed. In the groups treated with acepromazine, the heart rate stabilised sooner, and the red blood cell (RBC) count, haemoglobin concentration, packed-cell volume, the serum activities of creatine kinase (CK), aspartate aminotransferase (AST), alanine aminotransferase (ALT) and lactate dehydrogenase (LDH) and the concentrations of creatinine and lactate were significantly lower, and serum glucose started to decrease earlier, than in the untreated groups. Serum potassium levels decreased over time only in the untreated groups. The body temperature stabilised earlier, and the RBC count, haemoglobin concentration, serum CK, AST, ALT and LDH activities, and serum creatinine, lactate, cholesterol and glucose concentrations were significantly lower in the free-ranging roe deer than in the captive deer.     

The use of selected plasma enzyme activities for the diagnosis of fatty liver-hemorrhagic syndrome in laying hens

Profiles of plasma enzymes were compared in two strains of single comb white leghorn laying hens, a normal commercial strain and strain UCD-003, which is highly susceptible to fatty liver-hemorrhagic syndrome. Plasma activity of lactate dehydrogenase (LDH), glutamate dehydrogenase (GDH), aspartate aminotransferase (AST), alanine aminotransferase (ALT), and creatine kinase (CK) averaged 194 +/- 27, 4.0 +/- 2.8, 146 +/- 20, 1.0 +/- 1.0, and 1041 +/- 268 U/liter, respectively in normal birds. Activities of LDH, GDH, AST, and ALT, but not CK, were significantly higher in UCD-003 than in normal hens. A bimodal distribution of activities of all enzymes was found in the UCD-003 hens, with some birds showing activities comparable with those of the normal hens and others with values that were 2-10 times greater than those found in normal hens. These results are consistent with the extensive hepatic lesions observed in the UCD-003 strain of birds. Average gross hemorrhagic scores from visual inspection (scale of 0-3) were 0.28 +/- 0.45 in normal birds and 1.63 +/- 0.94 in the UCD-003 birds. Even though no clear relationship was found between plasma enzyme activities and the extent of liver hemorrhage in individual birds, the UCD-003 hens consistently had average values significantly higher for plasma enzymes that indicate liver damage. The results suggest that measurement of enzyme activities indicative of liver damage in birds, particularly AST, LDH, and GDH, is a valuable tool in the diagnosis of fatty liver-hemorrhagic syndrome in a flock of layers.     

断奶日龄对五指山仔猪生长性能和血清生化指标的影响

本试验旨在研究断奶日龄对五指山仔猪生长性能和血清生化指标的影响。选取日龄相近(±1 d)、体重[(0.56±0.07)kg]相近的五指山仔猪96头,随机分成4组,每组设4个重复,每个重复6头猪。4组仔猪分别在21、28、35和42日龄断奶。试验从8日龄开始,至56日龄结束,试验期间定期测定体重、采食量和血清生化指标。结果表明:各组仔猪断奶后平均日增重(ADG)出现不同程度的下降,且断奶日龄越早,ADG下降幅度越大;35日龄断奶组和42日龄断奶组21~28日龄、28~35日龄、35~42日龄、49~56日龄阶段的ADG显著高于21日龄断奶组(P0.05)。各组仔猪断奶后平均日采食量(ADFI)显著增加(P0.05),42日龄以后,各组ADFI无显著差异(P0.05)。21日龄断奶组、28日龄断奶组、35日龄断奶组血清总蛋白(TP)、白蛋白(ALB)、免疫球蛋白G(IgG)、免疫球蛋白M(IgM)含量以及谷丙转氨酶(ALT)、谷草转氨酶(AST)、乳酸脱氢酶(LDH)活性在断奶后7 d均发生显著变化(P0.05),并以21日龄断奶组波动最大;与35日龄断奶组和42日龄断奶组相比,21日龄断奶组28、35日龄时血清TP、ALB、IgG、IgM含量显著降低(P0.05),ALT、AST、LDH活性显著提高(P0.05),到56日龄时,血清TP、IgG、IgM含量仍显著低于35日龄断奶组和42日龄断奶组(P0.05)。21日龄断奶组血清甘油三酯(TG)、胆固醇(CHOL)含量在28~56日龄间存在显著变化(P0.05),35日龄断奶组和42日龄断奶组血清TG、CHOL含量在整个试验期内均无显著变化(P0.05)。35日龄断奶组血清TP、ALB、IgG、IgM含量以及ALT、AST、LDH活性除在42日龄时与42日龄断奶组存在显著差异(P0.05)外,其余时间点与42日龄断奶组均无显著差异(P0.05)。由此得出,35或42日龄断奶的五指山仔猪在生长性能、血清生化指标及免疫机能方面优于21日龄断奶的五指山仔猪。     

Application of the Vettest 8008 system for the biochemical analysis of vervet monkey plasma

A clinical biochemistry analyser designed specifically for veterinary use was used to analyse plasma samples from 24 vervet monkeys (Cercopithecus aethiops). Two millilitres of heparinised blood was collected from each of the 24 monkeys on four occasions at intervals of one week. Plasma was separated and analysed for the concentrations of triglycerides, cholesterol, total proteins, albumin, globulins, creatinine and blood urea nitrogen (BUN) and the activities of alkaline phosphatase (AP), lactate dehydrogenase (LDH), alanine aminotransferase (ALT), aspartate aminotransferase (AST), and creatine kinase (CK). The tests were easy to perform, used small volumes of plasma, and yielded consistent results for most of the analytes. The activities of CK and AP, but not AST, appeared to be influenced by haemolysis, and there were significant individual variations in the activity of LDH.     

Blood Chemistry and Histological Properties of Wild and Cultured Sea Bass (<Emphasis Type="Italic">Dicentrarchus labrax</Emphasis>) in the North Adriatic Sea

Histological and biochemical procedures were employed to study liver histomorphology and plasma levels of aspartate aminotransferases (AST), alanine aminotransferase (ALT), triglyceride (TRIG), cholesterol (CHOL), glucose (GLU) and total protein (TP) in cultured (CSB) and wild sea bass (WSB) (Dicentrarchus labrax) from the northern part of the Adriatic Sea. Histopathological changes in liver included varying degrees of infiltration and lipid degeneration of hepatocytes in examined cultured fish. No significant differences between median AST values of CSB (44 IU) and WSB (45 IU) were observed. Values of ALT were <5 IU in both groups. TRIG, CHOL, GLU and TP levels were higher in CSB (2.08 mmol/L, 3.67 mmol/L, 10.66 mmol/L and 49 g/L, respectively) than in WSB (0.67 mmol/L, 2.74 mmol/L, 3.68 mmol/L and 36 g/L, respectively). The study showed differences between plasma biochemical parameters and liver histomorphology of CSB and WSB. This can be explained as a consequence of different diets (artificial in contrast to natural foods), which influence energy metabolism.     

Activities of some serum enzymes in halothane reacted and non-reacted pigs

Eight- and nine-week-old Hungarian Landrace pigs were tested with halothane as described by Laky et al. (1985). Immediately after the test blood samples were taken for determination of the activity of serum creatine kinase (CK), creatine kinase MB (CK-MB) isoenzyme, aldolase (ALD), lactate dehydrogenase (LDH) and alpha-hydroxybutyrate dehydrogenase (alpha-HBDH). Elevated creatine kinase, creatine kinase MB isoenzyme and aldolase activities indicating enhanced susceptibility to stressors were found in 92% of the halothane reacted and 16% of the halothane non-reacted animals. In these individuals the activities of lactate dehydrogenase and alpha-hydroxybutyrate dehydrogenase were also high. Data of the literature show a close relationship between enhanced susceptibility to stressors and halothane reaction in pigs. It was suggested, therefore, that determination of the activity of appropriate serum enzymes might be used for detecting this enhanced susceptibility.     

Activity of some enzymes in the serum of dromedary camels.

The activities of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), acid phosphatase (ACP), lactate dehydrogenase (LDH) and isocitric dehydrogenase (ICD) in the serum of 60 healthy dromedary camels of either sex and different ages (one to 25 years) were determined. The results were analysed with respect to time of year (December-January and May-June), sex and age groups (below four years; four to 10 years; and over 10 years). The overall mean activities of AST, ALT, ALP, ACP, LDH and ICD were 36.1 +/- 0.35, 4.65 +/- 0.35, 27.21 +/- 0.43, 7.18 +/- 0.21, 479.0 +/- 7.33 and 7.74 +/- 0.17 iu litre-1, respectively. Activities of AST, ALT, ALP and ACP were significantly higher during extremely hot conditions (May-June) than in extreme cold (December-January) while the activity of LDH was higher in extremely cold conditions. Analysis of data based on sex revealed that AST, ALT and ALP activities in the serum of male animals were significantly higher than in female animals. The activities of all the enzymes were highest in animals under four years and then gradually decreased with age being lowest in the animals over 10 years.     

Effect of nickel deficiency on biochemical variables in serum, liver, heart and kidneys of goats.

Nickel deficiency was induced in 2- to 4-year-old goats by feeding 0.1 mg Ni/kg dry matter with a semisynthetic diet. The control group consumed 5.0 mg Ni/kg d.m. Activity of several enzymes (SDH, LDH, HBDH, AST, ALT, ALD, CK, CHE) was determined in the serum, liver, heart and kidneys. Serum urea-N level was also measured and transmission electron microscopic (TEM) examinations were performed. Signs characteristic of nickel deficiency (retarded growth, increased mortality of dam and offspring, parakeratosis of the skin) appeared in the low-nickel group. The activity of SDH and ALD, as well as the level of urea-N was significantly lower in the serum of Ni-deficient animals than in the control. Ni-deficient animals also had significantly lower enzyme activities in the heart (SDH, HBDH, AST, ALT, ALD and CK), liver (SDH and CHE) and kidneys (HBDH and CK). Electron micrographs showed degeneration of cardiac and skeletal muscle in the Ni-deficient animals. Ni deficiency elicited changes primarily in the heart and these resulted in depressed activity of several enzymes.     

Serum enzyme activity evaluated in budgerigars (Melopsittacus undulatus) inflicted with muscle injury

Aspartate aminotransferase (AST), alanine aminotransferase (ALT), creatine kinase (CK) and lactate dehydrogenase (LDH) concentrations were measured in 73 budgerigars. In spite of increases in the serum concentration of AST and ALT the loss of enzyme activity from the injection site occurred at about the same rate for all four enzymes tested. The rate constants, calculated in birds administered muscle extract via the intravenous or the intramuscular route of injection, disclosed that in subjects treated intramuscularly the serum enzyme elevation was dependent on the elimination half-life of the enzyme and partly on the rate at which the particular enzyme was absorbed into the bloods-tream. Moreover, serum enzyme elevations correlated inversely with total clearance. To determine the aetiology of blood enzyme elevation in budgerigars, for diagnostic purposes, the absorption rate, total clearance and elimination half-life of each of these four enzymes are deemed valuable components.     

Tissue and plasma enzyme activities in juvenile green iguanas

OBJECTIVE: To determine activities of intracellular enzymes in 8 major organs in juvenile green iguanas and to compare tissue and plasma activities. ANIMALS: 6 green iguanas < 1 year old. PROCEDURE: Lysates of liver, kidney, epaxial muscle, heart, lung, spleen, small intestine, and pancreas were analyzed for alkaline phosphatase (ALP), lactate dehydrogenase (LDH), aspartate transaminase (AST), alanine transaminase (ALT), gamma-glutamyltransferase (GGT), creatine kinase (CK), glutamate dehydrogenase (GMD), and amylase (AMS) activities. RESULTS: In general, low tissue enzyme activity coincided with low plasma activity. The CK activity was high in epaxial muscle and the heart and low in all other tissues tested. The AMS activity was found exclusively in the pancreas. Moderate LDH and AST activities were found in all tissues. Low ALT and ALP activities were found in a variety of tissues. Plasma and tissue activities of GGT and GMD were low or undetectable. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that plasma CK activity may be muscle specific in iguanas, but high values may not always indicate overt muscle disease. The AMS activity may be specific for the pancreas, but the wide range of plasma activity would likely limit its diagnostic usefulness. Activities of AST and LDH may reflect tissue damage or inflammation, but probably do not reflect damage to specific tissues or organs.     

Influence of dietary tannic acid and polyethylene glycol on growth and intestinal D-xylose absorption of broiler cockerels and activity of serum enzymes

1. In an experiment on broiler cockerels, the influence of tannic acid (TA) and polyethylene glycol (PEG) on body weight gain (BWG), feed conversion ratio (FCR), weight of intestine and liver, the activities of serum enzymes LDH, AST, ALT and intestinal absorption function were investigated. 2. Broiler cockerels were given either a commercial diet alone (control group) or a commercial diet with TA (20 g/kg), PEG (10 g/kg) or TA plus PEG (20 + 10 g/kg), for 10 d. 3. On the last day of the experiment, all birds and remaining feed were weighed individually and a sample of blood was taken to measure the serum activities of lactate dehydrogenase (LDH), aspartate aminotransferase (AST) and alanine aminotransferase (ALT). The capacity of intestinal cells for the absorption of D-xylose was measured. Finally all birds were killed humanely and the intestine and liver were weighed. 4. The results showed that TA significantly reduced BWG and FCR, as well as the activity of LDH, AST and ALT. 5. TA also increased the relative weight of the intestine. Adding PEG alone had no effect on any of the measured parameters. 6. However, PEG improved significantly BWG, FCR and the activity of LDH and AST of TA-fed birds. 7. The plasma D-xylose concentration of experimental birds was similar for all dietary treatments most likely because of temporal separation between feeding the dietary TA and administering the D-xylose. 8. It was concluded that the presence of tannins in the GI lumen of the bird was necessary to affect the processes involved in the absorption of simple sugars such as D-xylose, at the level of intestinal absorptive cells.     

Effect of in vitro Hemolysis on Values for Certain Porcine Serum Constituents

Serum consistuents were determined for 14 healthy pigs after the addition of hemolysates containing 54, 133, 215 and 400 mg/dl of hemoglobin to serum. Of sixteen chemical procedures considered, changes (P<0.0005) in creatinine, total protein, Pi, alanine aminotransferase (ALT), lactate dehydrogenase (LDH), Ca, K, aspartate aminotransferase (AST), total bilirubin and albumin values occurred following the addition of a hemolysate containing 400 mg/dl of hemoglobin. Changes (P<0.0005) were also observed in certain serum constituents when hemolysates containing 54, 133 and 215 mg/dl of hemoglobin were added.     

Distribution of tissue enzymes in three species of pinnipeds.

In domestic animal medicine, changes in serum enzyme levels are routinely used as diagnostic tools to detect liver disease. Hepatic disease occurs in pinnipeds, but limited data are available on the tissue distribution of serum enzymes in marine mammals. The objectives of this study were to determine the tissue distribution of seven serum enzymes in three pinniped species. Enzymes evaluated were alanine aminotransferase (ALT), aspartate aminotransferase (AST), sorbitol dehydrogenase (SDH), lactate dehydrogenase (LDH), creatine kinase (CK), alkaline phosphatase (ALP), and gamma-glutamyl transferase (GGT) in tissues from California sea lions (Zalophus californianus) (n = 5), harbor seals (Phoca vitulina) (n = 5), and northern elephant seals (Mirounga angustirostris) (n = 5) that stranded and then died at a rehabilitation center. Samples were evaluated in duplicate from liver, skeletal muscle, cardiac muscle, kidney, adrenal, spleen, pancreas, lung, lymph node, and intestine. Patterns of tissue enzyme distribution were similar in all species, with SDH activity highest in liver and kidney, CK activity highest in skeletal and cardiac muscle, ALP activity highest in adrenal, and GGT activity highest in the kidney. Aspartate aminotransferase and LDH activities were less specific, with high activity in multiple tissues. Tissue ALT activity was high in the liver of all species, but was also high in cardiac muscle (California sea lions), skeletal muscle (harbor seals), and kidney (elephant seals). These results suggest that concurrent analysis of SDH, ALT, and CK would provide high specificity and sensitivity for the detection of hepatic lesions, and allow differentiation of liver from skeletal muscle lesions in pinniped species.     

Hepatic effects of halothane, isoflurane or sevoflurane anaesthesia in dogs

The effects of halothane, isoflurane and sevoflurane anaesthesia on hepatic function and hepatocellular damage were investigated in dogs, comparing the activity of hepatic enzymes and bilirubin concentration in serum. An experimental study was designed. Twenty-one clinically normal mongrel dogs were divided into three groups and accordingly anaesthetized with halothane (n = 7), isoflurane (n = 7) and sevoflurane (n = 7). The dogs were 1-4 years old, and weighed between 13.5 and 27 kg (18.4 +/- 3.9). Xylazine HCI (1-2 mg/kg) i.m. was used as pre-anaesthetic medication. Anaesthesia was induced with propofol 2 mg/kg i.v. The trachea was intubated and anaesthesia maintained with halothane, isoflurane or sevoflurane in oxygen at concentrations of 1.35, 2 and 3%, respectively. Intermittent positive pressure ventilation (tidal volume, 15 ml/kg; respiration rate, 12-14/min) was started immediately after intubation and the anaesthesia lasted for 60 min. Venous blood samples were collected before pre-medication, 24 and 48 h, and 7 and 14 days after anaesthesia. Serum level of aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP) and gamma-glutamyltransferase (GGT), lactate dehydrogenase (LDH GGT) activities and bilirubin concentration were measured. Serum AST, ALT and GGT activities increased after anaesthesia in all groups. In the halothane group, serum AST and ALT activities significantly increased all the time after anaesthesia compared with baseline activities. But in the isoflurane group AST and ALT activities increased only between 2 and 7 days, and in the sevoflurane group 7 days after anaesthesia. GGT activity was increased in the halothane group between 2 and 7 days, and in the isoflurane and sevoflurane groups 7 days after anaesthesia. All dogs recovered from anaesthesia without complications and none developed clinical signs of hepatic damage within 14 days. The results suggest that the use of halothane anaesthesia induces an elevation of serum activities of liver enzymes more frequently than isoflurane or sevoflurane from 2 to 14 days after anaesthesia in dogs. The effects of isoflurane or sevoflurane anaesthesia on the liver in dogs is safer than halothane anaesthesia in dogs.     

Normal serum activities of some diagnostic enzymes in dromedary camel in Sudan

76 adult camel (30 males and 46 females) sera were surveyed for the normal activities of alkaline phosphatase (ALP), alanine aminotransferase (ALT), aspartate aminotransferase (AST), creatine phospho-kinase (CPK), -glutamyl transpeptidase (GGT) and lactate dehydrogenase (LDH). The values recorded for the above enzymes were compared to other data in the literature.     

An association between the level of oxidative stress and the concentrations of NEFA and BHBA in the plasma of ketotic dairy cows

The aim of this study was to evaluate the oxidative status in ketotic cows. We observed changes in the oxidative status and correlations between the oxidative and metabolic status in non‐ketotic (n = 10), subclinical ketotic (n = 10) and ketotic cows (n = 10). Plasma samples were analysed by standard biochemical techniques and ELISA to determine traditional metabolic parameters: triglyceride (TG), phosphonium (P), calcium (Ca), aspartate aminotransferase (AST), alanine aminotransferase (ALT), alkaline phosphatase (ALP), total protein (TP), albumin (ALB), immune globulin (Ig), total cholesterol (TC), high‐density lipoprotein (HDL), very low‐density lipoprotein (VLDL) and lactate dehydrogenase (LDH); energy metabolism indices: glucose, β‐hydroxybutyrate (BHBA) and non‐esterified fatty acids (NEFA); and indices of oxidative status: malondialdehyde (MDA), hydrogen peroxide (H₂O₂), vitamin C, vitamin E, superoxide dismutase (SOD), glutathione peroxidase (GSH‐Px), catalase (CAT), xanthine oxidase (XOD) and total antioxidant capacity (TAOC). The results of this study showed that plasma glucose levels were lower in ketotic and subclinical ketotic cows than in non‐ketotic cows; however, the plasma NEFA and BHBA concentrations were higher. In addition, significant decreases in TC, HDL and VLDL and significant increases in AST, ALT and LDH were observed in the plasma of the ketotic cows. The ketotic cows showed decreased plasma SOD, CAT, vitamin C and vitamin E, inhibited hydroxyl radical capacity and increased plasma H₂O₂ and MDA. There were positive correlations between the plasma NEFA and ALT, AST, LDH and MDA and negative correlations between the plasma NEFA and TC, HDL, VLDL, SOD, vitamin C, vitamin E, 1542280 uric acid and inhibited hydroxyl radical capacity. In addition, there were positive correlations between BHBA concentrations and ALT, AST and LDH and negative correlations between plasma BHBA concentrations and TC, HDL, VLDL, vitamin E and inhibited hydroxyl radical capacity. Overall, ketotic dairy cows experience oxidative stress, which is presumably associated with hyperketonemia and higher NEFA.     

１～２１日龄不同性别北京鸭核黄素需要量的估测

本试验旨在估测 １～２１日龄不同性别北京鸭核黄素的需要量。采用 ２（性别：公、母）×９（饲粮核黄素水平：１．２、３．２、５．２、７．２、９．２、１１．２、１３．２、１５．２、４１．２ｍｇ／ｋｇ）双因子完全随机试验设计,选取体重相近的 １日龄健康的 Ｚ３系北京鸭公鸭和母鸭各 ３６０只,公鸭和母鸭均随机分为 ９组,每组 ５个重复,每个重复 ８只鸭。结果表明：性别对 １～２１日龄北京鸭的平均日增重和料重比有显著影响（Ｐ＜０．０５）,对平均日采食量、血浆核黄素水平以及血浆谷丙转氨酶（ＡＬＴ）、天冬氨酸转氨酶（ＡＳＴ）、乳酸脱氢酶（ＬＤＨ）活性均无显著影响（Ｐ＞０．０５）。饲粮核黄素水平对 １～２１日龄北京鸭平均日增重、平均日采食量、料重比、血浆核黄素水平以及血浆ＡＬＴ、ＡＳＴ、ＬＤＨ活性均有显著影响（Ｐ＜０．０５）。结果提示,分别以平均日增重、平均日采食量、料重比和血浆核黄素水平为评价指标,采用折线模型估测 １～２１日龄北京鸭公鸭核黄素需要量分别为３．３１、３．２４、５．２０、３．８２ｍｇ／ｋｇ,母鸭核黄素需要量分别为 ３．２７、３．１９、３．３３、３．８４ｍｇ／ｋｇ。