Rectal temperature responses of donkeys administered with ascorbic acid and subjected to load carrying (packing) during the harmattan season in Nigeria

The aim of the experiment was to evaluate the effect of 4-h load carrying (packing) on donkeys administered with ascorbic acid (AA) during the harmattan season. Six donkeys administered orally with ascorbic acid (200 mg/kg) and subjected to packing served as experimental animals, while six others given only distilled water served as control animals. The rectal temperature (RT) of each donkey and dry-bulb temperature (DBT) and relative humidity (RH) of the research pen were recorded at 0600 hours pre-packing; while post-packing, the values were obtained at 1430, 1600 and 1800 hours. The DBT values (ranges) recorded before, during and after packing were 13.7?±?1.3 °C (11–15 °C), 28.4?±?1.0 °C (22.7–30.3 °C) and 30.6?±?3.0 °C (19.8–45 °C), respectively. The highest temperature–humidity index (THI) of 83.4?±?6.9 was obtained at 1430 hours after packing, and the value decreased to 64.2?±?5.8 at 1800 hours. The thermal environmental conditions were outside the thermoneutral zone for the donkeys. The RT values recorded immediately after packing did not differ (P?>?0.05) in experimental and control donkeys; but at 1600 and 1800 hours, values obtained in control donkeys (38.48?±?0.12 and 38.12?±?0.12 °C, respectively) were significantly higher (P?<?0.05) than those recorded in experimental donkeys (38.16?±?0.14 and 37.85?±?0.14 °C, respectively). In conclusion, administration of ascorbic acid reduced the rise in RT due to packing and may be of value in the amelioration of adverse effects of heat stress associated with work in donkeys.     

Erythrocyte Osmotic Fragility and Hematological Responses of Horses Administered Ascorbic Acid and Exposed to Road Transportation

The experiment was performed to evaluate the ameliorative effect of ascorbic acid (AA) on some hematological parameters and erythrocyte osmotic fragility (EOF) in horses transported by road. A total of 14 horses, consisting of seven experimental and seven control horses, were used for the experiment. Before the transportation, blood samples were obtained by jugular venipuncture from all the horses. Experimental horses were administered with AA (200 mg/kg dissolved in 20 mL of distilled water per os), whereas the control horses were given 20 mL of distilled water per os. Thereafter, the animals were transported for 6 hours and blood samples collected after transportation. Packed cell volume and hemoglobin concentration were higher (P < .05) in experimental than the control group, whereas total leukocytes reduced significantly (P < .05) in experimental in comparison with the control horses. Lymphocyte, neutrophil counts, neutrophil/lymphocyte ratio, and total protein decreased in experimental horses in comparison with control, but they were not significant (P > .05). Erythrocyte osmotic fragility was lower in experimental than the control at 0.3% NaCl concentration (P < .05). The result of the present study revealed that AA ameliorated changes in hematological parameters and EOF induced by road transport stress, partly because of its antioxidant properties.     

Blood Parameters of Healthy Mink

Packed cell volume (PCV) and hemoglobin (Hb) were not dependent on color type. Both were significantly higher (P < 0.01) in the adult male mink as compared to the adult female. The total erythrocyte count was more variable but the parameter appeared unaffected by either sex or color types. Polychromasia, reticulocytes and the occasional normoblast, were present in peripheral mink blood smears. Rouleau, to some degree. was also seen. The most variable parameter was the total leukocyte count. The average lymphoidneutrophil ratio was 1:1.     

Hematology and serum biochemistry of captive Sunda pangolin (Manis javanica) in Wildlife Reserves Singapore

The Sunda pangolin (Manis javanica) faces threat of extinction due to illegal trafficking of its scales for the purpose of traditional medicine in the Asian region. Ex-situ captive breeding and reintroduction programs have been identified to be a key effort in the conservation of the species. The establishment of blood parameters for captive Sunda pangolins are vital to assess the health in these animals during health assessments. The objective of this study is to establish blood parameters for captive Sunda pangolins and compare the blood parameters with the established blood reference ranges for rescued wild Sunda pangolins in Singapore. Blood parameters for hematology and serum biochemistry were established from 13 clinically normal captive Sunda pangolins. Male captive Sunda pangolins were found to have significantly (P<0.05) higher potassium compared to the female captive Sunda pangolins. Captive Sunda pangolins were found to have significantly (P<0.05) lower white blood cell count (WBC), neutrophil counts, alanine phosphatase (ALP) and phosphorus and significantly (P<0.05) higher PCV, TP, globulin and blood urea nitrogen (BUN) when compared with rescued wild Sunda pangolins from the previous study.     

日粮添加免疫生长促进剂C96对雏鸡若干血液指标的影响

选择１２０只１日龄ＡＡ商品健康雏鸡,随机分为４组,每组３０只。初步观察了日粮添加免疫生长促进剂Ｃ９６对血液中红细胞总数（ＲＢＣ）、比容（ＰＣＶ）、血红蛋白含量（Ｈｂ）、网织红细胞比例（ＲＣＣ）、白细胞总数（ＷＢＣ）等的影响。结果表明：肉雏鸡在１５ｄ时,日粮添加Ｃ９６为１１ｍｇ／ｋｇ,饲料的Ｃ９６组和疫苗－Ｃ９６组,与对照组和疫苗组比较,ＲＢＣ和Ｈｂ增高,ＷＢＣ显著下降,ＲＣＣ降低,ＰＣＶ无明显规律性变化;３０ｄ和４５ｄ时,添加Ｃ９６组和疫苗－Ｃ９６组的ＲＢＣ、Ｈｂ和ＰＣＶ,与对照组和疫苗组基本相近,ＷＢＣ和ＲＣＣ均比对照组和疫苗组低或明显低。但３０ｄ时疫苗组的ＷＢＣ比对照组高。整个试验期,ＲＢＣ、ＷＢＣ和ＰＣＶ随日龄的增长呈上升趋势,ＲＣＣ呈波动性下降。     

A comparative efficacy test of 1 versus 2 doses of CIRCOQ PCV2 subunit vaccine against naturally occurring PCV2-type d in piglets with high maternally derived antibodies (MDAs) on a Vietnamese swine farm

The aim of this study was to evaluate the protective efficacy of the CIRCOQ porcine circovirus type 2 (PCV2) subunit vaccine in piglets with high maternally derived antibodies (MDAs) against disease caused by natural infection with PCV2d. A total of 130 weaned, 21-day-old healthy pigs was allocated into 3 trial groups. The signs of respiratory disorder were higher in unvaccinated pigs than in vaccinated pigs at 13 to 17 weeks old (P < 0.05), 18 to 22 weeks old (P < 0.001), and 23 to 27 weeks old (P < 0.01). The unvaccinated pigs had an early rate of dermatitis at 8 to 12 weeks old (10.0%), 13 to 17 weeks old (30.0%), 18 to 22 weeks old (46.7%), and 23 to 27 weeks old (33.3%), while there were no cases of dermatitis in vaccinated pigs. There was a significant difference (P < 0.05) in the mortality of pigs in the unvaccinated group and the 2-dosed vaccinated group. PCV2 viremia was detected in the blood and peaked at 105 days old in both unvaccinated pigs (Ct-adj = 8.40) and pigs vaccinated with 1 dose (Ct-adj = 6.37), while no detectable PCV2 virus was found in the blood of pigs vaccinated with 2 doses. At 77 and 105 days old, the PCV2 viremia load (Ct-adj) of unvaccinated pigs and those vaccinated with 1 dose was significantly higher (P < 0.05) than that of the 2-dosed vaccinated pigs. The body weight (BW), average weight gain (AWG), and average daily gain (ADG) in both groups of vaccinated pigs were significantly higher (P < 0.05) than those of unvaccinated pigs. The study vaccine was significantly efficacious in protecting vaccinated pigs against clinical symptoms, blood viral load, and mortality, as well as improving productivity, compared with unvaccinated pigs.     

缺铁性贫血对仔猪免疫功能的影响

采用醋酸纤维薄膜电泳分析和＾３Ｈ－ＴｄＢ掺入法，研究了仔猪缺铁性贫血对免疫功能的影响。试验于补铁治疗前后检测了血常规３个指标、免疫学２个的指标，结果显示：出生后不予补铁的仔猪，其血红蛋白、红细胞压积（ＰＣＶ）、红细胞数（ＲＢＣ）均显著降低，从而严重影响了仔猪的免疫功能，其中对细胞免疫功能的影响尤为显著（Ｐ＜０．０１），而血清丙球蛋白（ｒ－Ｉｇ）百分比的平均值略高于不治疗对照组，但差异无显著性（Ｐ＞     

Physiological responses of transported goats treated with ascorbic acid during the hot-dry season

The aim of the present study was to determine the physiological responses of transported Red Sokoto goats (RSG) treated with ascorbic acid (AA). Ten RSG treated orally with ascorbic acid served as experimental subjects, while seven goats treated with sterile water served as the control. The goats were transported for 8 h. The ambient temperature and relative humidity during the study period fluctuated between 21 and 38°C and 51 and 91%, respectively, which indicated that the season was thermally stressful and did not favor transportation of goats. The rectal temperature obtained in the control goats was significantly higher (P < 0.01) than the value in the experimental goats after transportation. There was a significant decrease (P < 0.05) in eosinophil counts and an increase (P < 0.01) in neutrophil counts and neutrophil : lymphocyte ratio recorded in the control goats after transportation, which suggested that the control goats were physically and emotionally stressed. The control goats lost 11.9% of their initial liveweight, while the experimental goats lost only 1.04% after transportation. Multiple stresses, including extreme meteorological factors, acted upon the transported goats and impaired their homeostatic mechanism. In conclusion, AA administration in goats reduced the adverse effects of road transportation stress.     

家兔在西藏海拔3000m条件下部分生理特性的试验观察

试验对海拔 3 0 0 0m的藏南谷地林芝引入家兔进行了部分生理指标的对比分析。测定了呼吸频率、心率、生理体温、血清蛋白质含量和血红蛋白含量。统计分析表明 :所测定项目的结果在 3品种兔之间均无明显差异 (P >0 0 5) ;但血红蛋白电泳分析 :3品种兔均呈现出A、A2 ,A33个区带 ,发现A3带以青紫兰兔最低 ,与其他 2品种兔差异极显著 (P <0 0 1 ) ;加里福尼亚兔A3带最高 ,显著高于中国白兔 (P <0 0 5)及青紫兰兔 (P <0 0 1 )。血清蛋白质电泳分析表明 :高原家兔的血清白蛋白均明显高于文献报道的低海拔饲养的新西兰白兔 ,血清总蛋白及其球蛋白含量明显下降     

Effects of dietary iron level on growth performance,hematological status,and intestinal function in growing-finishing pigs

This study investigated the different addition levels of iron (Fe) in growing-finishing pigs and the effect of different Fe levels on growth performance, hematological status, intestinal barrier function, and intestinal digestion. A total of 1,200 barrows and gilts ([Large White × Landrace] × Duroc) with average initial body weight (BW; 27.74 ± 0.28 kg) were housed in 40 pens of 30 pigs per pen (gilts and barrows in half), blocked by BW and gender, and fed five experimental diets (eight replicate pens per diet). The five experimental diets were control diet (basal diet with no FeSO₄ supplementation), and the basal diet being supplemented with 150, 300, 450, or 600 mg/kg Fe as FeSO₄ diets. The trial lasted for 100 d and was divided into the growing phase (27 to 60 kg of BW) for the first 50 d and the finishing phase (61 to 100 kg of BW) for the last 50 d. The basal diet was formulated with an Fe-free trace mineral premix and contained 203.36 mg/kg total dietary Fe in the growing phase and 216.71 mg/kg in the finishing phase based on ingredient contributions. And at the end of the experiment, eight pigs (four barrows and four gilts) were randomly selected from each treatment (selected one pig per pen) for digesta, blood, and intestinal samples collection. The results showed that the average daily feed intake (P = 0.025), average daily gain (P = 0.020), and BW (P = 0.019) increased linearly in the finishing phase of pigs fed with the diets containing Fe. On the other hand, supplementation with different Fe levels in the diet significantly increased serum iron and transferrin saturation concentrations (P < 0.05), goblet cell numbers of duodenal villous (P < 0.001), and MUC4 mRNA expression (P < 0.05). The apparent ileal digestibility (AID) of amino acids (AA) for pigs in the 450 and 600 mg/kg Fe groups was greater (P < 0.05) than for pigs in the control group. In conclusion, dietary supplementation with 450 to 600 mg/kg Fe improved the growth performance of pigs by changing hematological status and by enhancing intestinal goblet cell differentiation and AID of AA.     

Physiology and behavior of dogs during air transport

Twenty-four beagles were used to measure physiological and behavioral reactions to air transport. Each of 3 groups of 4 sedated (with 0.5 mg/kg body weight of acepromazine maleate) and 4 non-sedated (control) dogs was flown on a separate flight between Montreal, Quebec, and Toronto, Ontario, after being transported by road from Quebec City to Montreal. Saliva and blood samples were taken before ground and air transport and after air transport. The heart rate was monitored during the whole experiment except during ground transport, and behavior was monitored by video during air transport. Sedation did not affect any of the variables measured. The mean plasma cortisol concentration was significantly higher (P < 0.05) after ground transport than at baseline (225.3 vs 134.5 nmol/L); the mean salivary cortisol concentration was significantly higher (P < 0.05) after both ground and air transport than at baseline (16.2 and 14.8, respectively, vs 12.6 nmol/L). The mean neutrophil count was significantly higher (P < 0.05) after both ground and air transport than at baseline (80.6 and 81.4, respectively, vs 69.5 per 100 white blood cells), whereas the mean lymphocyte count was significantly lower (P < 0.05) (13.2 and 13.7, respectively, vs 22.4 per 100 white blood cells). Loading and unloading procedures caused the largest increase in heart rate. On average, the dogs spent more than 50% of the time lying down, and they remained inactive for approximately 75% of the time, except during take-off. These results suggest that transportation is stressful for dogs and that sedation with acepromazine, at the dosage and timing used, does not affect the physiological and behavioral stress responses of dogs to air transport.     

Pigs naturally exposed to porcine circovirus type 2 (PCV2) generate antibody responses capable to neutralise PCV2 isolates of different genotypes and geographic origins

Porcine circovirus type 2 (PCV2) is the essential infectious agent for PCV2-systemic disease (PCV2-SD, formerly known as postweaning multisystemic wasting syndrome) and other pathological conditions. Recent studies indicated antigenic variability amongst different PCV2 isolates and suggested that single amino acid changes within the capsid protein determine differences in the level of neutralization by specific monoclonal antibodies. The objective of the present study was to examine the cross-reactivity of PCV2 antibodies induced in the context of a natural infection against different PCV2 isolates belonging to genotypes PCV2a and PCV2b. Sera taken from several farms from animals of varying health status (PCV2-SD and age-matched healthy pigs and a set of slaughter-aged animals) were assayed for neutralizing activity against four PCV2 isolates from both predominant genotypes (PCV2a and PCV2b) and of differing geographic origins (Europe and North-America). Results showed that most of studied pigs (79 out of 82) contained neutralizing antibodies (NA) able to neutralize all four studied viral strains. Overall, pigs had significantly higher NA titres against PCV2a than against PCV2b (P < 0.001). Accordingly, studied serums were able to better neutralize Burgos390L4 and Stoon-1010 strains (PCV2a) than L-33-Sp-10-54 and MO/S-06 strains (PCV2b) (P < 0.001). No differences between capabilities of seroneutralization of viruses from different geographic origin were observed. Present data suggests that sequence differences between PCV2 isolates translate to functional antigenic differences in viral neutralization in vivo.     

Haematological profile of crossbred dairy cattle to monitor herd health status at medium elevation in Central Himalayas

Haematological profile-haemoglobin concentration (Hb), total erythrocytes count (TEC), packed cell volume (PCV), erythrocyte indices-mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH) and mean corpuscular haemoglobin concentration (MCHC) were studied in crossbred dairy cattle (Holstein Friesian x Sahiwal) under various physiological states: non-pregnant heifers (NPH), pregnant heifers (PH), empty dry cows (EDC), pregnant lactating cows (PLC), medium yield early lactating cows (MYELC) and high yield early lactating cows (HYELC) during summer and winter seasons at 1700 metres altitude from mean sea level in the Central Himalayas. On comparison of annual means, the highest values of Hb and PCV were recorded in PH and of TEC in NPH, whereas the lowest values of these parameters were found in EDC. The Hb and TEC tended to decrease with increasing milk yield. Comparison of annual means of erythrocyte indices revealed the highest MCV and MCH in EDC, which simultaneously showed the lowest MCHC. Significant seasonal variations in haematological profile were recorded. The overall group mean (OGM) of Hb, MCV, MCH and MCHC was found to be significantly higher (P < 0.01) during summer whereas the TEC and PCV showed higher OGM (P < 0.01) during the winter season.     

Excitability scores of goats administered ascorbic acid and transported during hot-dry conditions

In this study, we investigated the effect of ascorbic acid (AA) administration on goat excitability due to transportation. Ten goats administered AA (p.o.) at 100 mg/kg of body weight before transportation served as the experimental group, and seven goats administered only 10ml/kg of sterile water (p.o.) served as controls. Excitability scores were recorded for each goat; when weighed, before, immediately after, and 3 h after 8 h of transportation. A score of one to four was allocated to each goat; higher scores represent greater excitability. Immediately after transportation, excitability scores decreased significantly, especially those of control goats (p < 0.001). At 3 h post-transportation, the excitability scores of animals in the experimental group were not significantly (p>0.05) different from their pre-transportation normal values, whereas those of control goats were significantly lower (p < 0.01). The correlation i.e. the relationship between excitability score values and percent excitability (percentage of goat with particular excitability score) for different excitability score group 3 h post-transportation was positive and highly significant (p < 0.001), in both experimental and control goats. Our results indicate that road transportation induces considerable stress (depression) in goats as evidenced by a lower excitability score post-transportation. Moreover, the administration of AA pre-transportation facilitated the transition from a state of depression to excitation. In conclusion, AA administration to animals prior to transportation may ameliorate the depression often encountered after road transportation.     

Iron status and erythropoiesis response to darbepoetin alfa in dogs with chronic kidney disease

Iron metabolism, hepcidin and some blood profiles were investigated in 13 healthy and 31 chronic kidney disease (CKD) dogs. The study consisted of 2 experiments, experiment I included healthy dogs (CONT) and CKD dogs (stage 2, 3 and 4), while experiment II consisted of anemic CKD dogs subjected to 28-day darbepoetin alfa treatment. The response to darbepoetin alfa could divide anemic CKD dogs into responder (RP) and non-responder (NRP) subgroups. The results from experiment I showed that packed cell volume (PCV) and plasma albumin concentration were significantly lower in CKD dogs of all stages while the total iron binding capacity (TIBC) was lower in only CKD stage 3 and 4 compared with dogs in CONT group. The PCV was related to both TIBC and albumin when considering among all dogs or only in CKD dogs. The hepcidin concentration in CKD dogs with anemia was lower than those without anemia (P<0.05). In experiment II before darbepoetin alfa treatment, RP subgroup had significantly higher iron and TIBC compared with NRP subgroup (P<0.05), the iron concentration was decreased only in RP subgroup after darbepoetin alfa treatment (P<0.05). The percent increase in PCV was correlated with initial TIBC (P<0.01). Plasma hepcidin concentration was not different between CONT and CKD groups and between RP and NRP subgroups both before and after darbepoetin alfa treatment. It is concluded that TIBC and plasma iron concentration play role on anemia and erythropoietic response to darbepoetin alfa treatment in CKD dogs.     

Comparative clinico-haematological analysis in young Zebu cattle experimentally infected with Trypanosoma vivax isolates from tsetse infested and non-tsetse infested areas of Northwest Ethiopia

Background

Ethiopia, particularly in the Northwest region, is affected by both tsetse and non-tsetse fly transmitted trypanosomosis, with significant impact on livestock productivity. The aim of this study was to determine and compare clinical findings and haematological values between experimental infections induced by Trypanosoma vivax isolates from areas of either transmission mode. Sixteen young (aged between 6 and 12 months) Zebu cattle (Bos indicus), purchased from a trypanosome-free area and confirmed to be trypanosome-negative, were randomly assigned into four groups of four animals. Groups 1, 2 and 3 were infected with an isolate from a tsetse infested or one of two isolates from a non-tsetse infested area, and group 4 was a non-infected control. All animals in the infected groups were inoculated intravenously with 2 × 10⁶ trypanosomes from donor animals. The experimental animals were monitored for eight consecutive weeks post infection for clinical signs, parasitaemia and haematological changes in packed cell volume (PCV), haemoglobin concentration (Hgb), total red blood cell (RBC) and white blood cell (WBC) counts, differential WBC count and blood indices (mean corpuscular volume [MCV], mean corpuscular haemoglobin and mean corpuscular haemoglobin concentration).

Results

Infection was characterized by reduced feed intake, weakness, pyrexia, parasitaemia, rough hair coat, enlarged prescapular lymph nodes, lacrimation, weight loss, pallor mucus membrane and dehydration. Body weight loss in all infected groups was significantly higher than in the non-infected control. Similarly, body weight loss was higher (P < 0.001) in animals infected with the tsetse infested isolate than with the non-tsetse infested isolates. The mean PCV, Hgb, total RBC and WBC counts were lower (P < 0.001), and mean MCV was higher (P = 0.01) in all infected groups than in non-infected control animals at different time points during the study period. Except for minor variations in haematological values, the overall changes were similar in all infected groups.

Conclusion

Clinical signs and significant reduction in haematological values in the infected groups indicated the pathogenicity of the T. vivax parasites. Pathogenicity of T. vivax from the non-tsetse infested area can be considered as nearly as important as that of its counterpart derived from the tsetse infested area.     

Effect of Yeast Culture (Saccharomyces cerevisiae) Supplementation on Growth Performance,Excreta Microbes,Noxious Gas,Nutrient Utilization,and Meat Quality of Broiler Chicken

The study was conducted to test the effects of using yeast culture (Saccharomyces cerevisiae) as feed additive on the growth performance, noxious gas emission, utilization of nutrients, excreta microbial count, and meat quality of broilers. In total, 360 one-day-old Ross 308 broilers with average body weight (BW) of 42.90±1.43 g were randomly selected and allotted to two groups; they were fed either a basal diet (control) or a basal diet supplemented with 1% yeast culture (YC). Each treatment group had 10 replication pens and each replication contained 18 birds. The experiment was divided into 3 phases (1 to 7, 8 to 21, and 22 to 35 days) for growth performance observation. In the 1^st phase (1 to 7 days), only the body weight gain (BWG) significantly increased (P<0.05) in birds with the YC diet compared to the control diet. Significant effects on BWG (P<0.05) and feed conversion ratio (FCR) (P<0.05) were seen in birds receiving the YC-supplemented diet in the 3^rd phase (22 to 35 days) as compared to the control diet. In addition, during the overall period (1–35 d), BWG was significantly higher (P<0.05) and FCR was reduced (P<0.05). Throughout this experiment, the meat quality, nutrient utilization, noxious gas emission, and bacterial count in the excreta did not vary significantly between the groups. This study proved that a higher dose of YC (Saccharomyces cerevisiae) supplementation could maintain the consistent positive effect on broiler growth but eliminated the speculated outcomes on digestibility, bacterial count, or excreta gas emission.     

Effects of xylazine,romifidine, or detomidine on hematology,biochemistry, and splenic thickness in healthy horses

Alpha-2 agonist-induced changes in packed cell volume (PCV), total solids (TS), selected biochemical parameters, and splenic thickness were investigated in horses. Four healthy mares were treated in a blinded, randomized, cross-over design with a dose of xylazine (0.5 mg/kg), romifidine (0.04 mg/kg), or detomidine (0.01 mg/kg) IV, and detomidine (0.02 mg/kg) IM. Hematology, TS, colloid osmotic pressure (COP), plasma osmolality; glucose, lactate, urea (BUN) and electrolyte concentrations; venous blood pH and ultrasonographic splenic thickness were evaluated at intervals for 300 min. Repeated measures analysis of variance (ANOVA) were performed with P < 0.05. There was a significant change over time in PCV and TS following each treatment (P < 0.001), with median (range) reductions of 20.9% (12.9% to 27.3%) and 5.8% (3.0% to 10.3%), respectively. Red blood cell count, BUN, and COP decreased while osmolality, glucose, Na⁺, and splenic thickness increased. Treatments induced clinically significant transient changes in PCV, TS, and other biochemical parameters, which should be considered when assessing horses that received these drugs.     

Erythrocytic oxidative damage in crossbred cattle naturally infected with Babesia bigemina

This study aimed to determine the erythrocytic lipid peroxidation and haemoglobin oxidation as contributory factors causing anaemia in cattle (Friesian × Egyptian native breed) infected with Babesia bigemina. Blood was collected from 32 cows infected with B. bigemina along with 18 healthy cows as controls for determination of erythrocytic malondialdehyde (MDA), blood methaemoglobin (MetHb), plasma free haemoglobin (PHb), corpuscular osmotic fragility (COF), red blood cell count (RBC), total haemoglobin (Hb) and packed cell volume (PCV). Percentage of parasitaemia varied from 14% to 36%. MDA, MetHb, COF and PHb were significantly increased (P < 0.001) in infected cows versus controls. Parasitaemia was positively correlated (P < 0.001) with MDA, MetHb, COF and PHb. MDA was positively correlated (P < 0.001) with COF and PHb and negatively correlated (P < 0.001) with RBC, Hb and PCV. MetHb was negatively correlated (P < 0.001) with RBC, Hb and PCV and positively correlated (P < 0.001) with COF. In conclusion, B. bigemina infection in cattle is associated with a parasitic burden-dependent corpuscular oxidative damage as indicated by membrane lipid peroxidation and methaemoglobin formation, which are contributed to COF and intravascular haemolysis.     

Dietary supplementation with N-carbamoylglutamate initiated from the prepartum stage improves lactation performance of postpartum dairy cows

The objective of this study was to investigate the effects of supplementing N-carbamoylglutamate (NCG), an Arg enhancer, on amino acid (AA) supply and utilization and productive performance of early-lactating dairy cows. Thirty multiparous Chinese Holstein dairy cows were randomly divided into control (CON, n = 15) and NCG (CON diet supplemented with NCG at 20 g/d per cow, n = 15) groups at 4 wk before calving. Diets were offered individually in tie-stalls, and NCG was supplemented by top-dress feeding onto total mixed ration for the NCG group. The experiment lasted until wk 10 after calving. Dry matter intake tended to be higher (P = 0.06), and yields of milk (P < 0.01), milk protein (P < 0.01), and milk fat (P < 0.01) were higher in the NCG-cows than in the CON-cows. Plasma activities of aspartate aminotransferase (P < 0.01), alanine aminotransferase (P = 0.03), and plasma level of β-hydroxybutyrate (P = 0.04) were lower in the NCG-cows than in the CON-cows, whereas plasma glucose (P = 0.05) and nitric oxide (NO, P < 0.01) concentrations were higher. Coccygeal vein concentrations of Cys (P < 0.01), Pro (P < 0.01), Tyr (P = 0.05), most essential AA except Thr and His (P < 0.01), total essential AA (P < 0.01), and total AA (P < 0.01) were higher in the NCG-cows than in the CON-cows. The arterial supply of all AA was greater in the NCG-cows than in the CON-cows. The NCG-cows had higher mammary plasma flow of AA (P = 0.04) and clearance rate of Cys (P < 0.01), Pro (P < 0.01) and Asp (P < 0.01), and higher ratios of uptake to output of Met (P = 0.05), Lys (P < 0.01), Cys (P = 0.01), Pro (P = 0.03), and Asp (P = 0.01). In summary, addition of NCG initiated from the prepartum period improved the lactation performance of postpartum dairy cows, which might attribute to greater Arg and NO concentrations, as well as improved AA supply and utilization, liver function, and feed intake in these cows.