Hyoscine‐N‐butylbromide premedication on cardiovascular variables of horses sedated with medetomidine

ObjectiveTo evaluate the effects of intravenous (IV) or intramuscular (IM) hyoscine premedication on physiologic variables following IV administration of medetomidine in horses.Study designRandomized, crossover experimental study.AnimalsEight healthy crossbred horses weighing 330 ± 39 kg and aged 7 ± 4 years.MethodsBaseline measurements of heart rate (HR), cardiac index (CI), respiratory rate, systemic vascular resistance (SVR), percentage of patients with second degree atrioventricular (2^oAV) block, mean arterial pressure (MAP), pH, and arterial partial pressures of carbon dioxide (PaCO₂) and oxygen (PaO₂) were obtained 5 minutes before administration of IV hyoscine (0.14 mg kg^?1; group HIV), IM hyoscine (0.3 mg kg^?1; group HIM), or an equal volume of physiologic saline IV (group C). Five minutes later, medetomidine (7.5 μg kg^?1) was administered IV and measurements were recorded at various time points for 130 minutes.ResultsMedetomidine induced bradycardia, 2^oAV blocks and increased SVR immediately after administration, without significant changes in CI or MAP in C. Hyoscine administration induced tachycardia and hypertension, and decreased the percentage of 2^oAV blocks induced by medetomidine. Peak HR and MAP were higher in HIV than HIM at 88 ± 18 beats minute^?1 and 241 ± 37 mmHg versus 65 ± 16 beats minute^?1 and 192 ± 38 mmHg, respectively. CI was increased significantly in HIV (p ≤ 0.05). Respiratory rate decreased significantly in all groups during the recording period. pH, PaCO₂ and PaO₂ were not significantly changed by administration of medetomidine with or without hyoscine.Conclusion and clinical relevanceHyoscine administered IV or IM before medetomidine in horses resulted in tachycardia and hypertension under the conditions of this study. The significance of these changes, and responses to other dose rates, requires further investigation.     

Adaptation of ostriches to transport‐induced stress: Physiometabolic response

This study assessed the effects of five different transport periods on physiometabolic responses and gas exchange in ostriches. It included 138 ostriches that were assigned to five experimental groups. G₁ included 78 birds that were set aside as a reference group (RG). Each one of the four remaining experimental groups included 20 ostriches, which were transported in the following manner: G₁ on one occasion for a period of 1 h; G₂ on one occasion for 2 h; and G₃ on one occasion for 3 h; G_4a was made up of the ostriches from G₁ but they were shipped on a second occasion, for 2 h (making a total of 3 h); finally, G_4b was that same group, but after a third transport period, on this occasion during 3 h (for a total of 6 h). Groups G₂ and G₃ presented the most marked blood alterations (P < 0.05), including an increase in pH, hypocapnia (27.8 ± 0.80 mmHg), hypernatremia (171.75 ± 1.84 mmol/L), hypocalcemia (0.95 ± 0.03 mmol/L), and hyperglycemia (224.05 ± 3.94 mg/dL). Also, group G₃ presented the lowest hematocrit values (26.5 ± 0.47 HTC%). Therefore, transporting ostriches with no prior experience for 3 h caused the most pronounced physiometabolic changes.     

Evaluation of a point‐of‐care blood glucose monitor in healthy goats

Objective

To assess agreement between a point‐of‐care glucometer (POCG) and a laboratory chemistry analyzer for blood glucose measurements in goats.

Design

Prospective study.

Setting

University teaching hospital.

Animals

Eighteen healthy adult goats.

Investigations

Whole blood samples were obtained via jugular venipuncture prior to premedication with xylazine and butorphanol (T0), following premedication (T20), and after 1 hour of inhalant anesthesia (T60). Each sample was tested with a POCG and a laboratory analyzer (HITA). Agreement was assessed using concordance correlation coefficients and calculation of bias and 95% limits of agreement.

Measurements and Main Results

Mean blood glucose concentration at T0 was 3.9 ± 0.6 mmol/L (70 ± 10 mg/dL; POCG) and 2.9 ± 0.4 mmol/dL (53 ± 8 mg/dL; HITA). Glucose concentrations at T20 were 6.7 ± 2.4 mmol/L (121 ± 43 mg/dL) and 5.4 ± 2.1 mmol/L (97 ± 37 mg/dL) and at T60 were 5.7 ± 1.7 mmol/L (102 ± 31 mg/dL) and 4.7 ± 1.3 mmol/L (85 ± 24 mg/dL) when measured with the POCG and HITA, respectively. The POCG overestimated blood glucose compared to the HITA. The bias ± SD was 1.08 ± 0.53 mmol/L (19.4 ± 9.5 mg/dL) (95% LOA 0.04 to 2.11 mmol/L [0.7 to 38.0 mg/dL]) and the concordance correlation coefficient was 0.82. After correcting the results of the POCG using a mixed‐effects linear model, the bias was 0.0 ± 0.38 mmol/L (0.0 ± 6.8 mg/dL) (95% LOA ± 0.74 mmol/L [± 13.4 mg/dL]) and the concordance correlation coefficient was 0.98.

Conclusions

The POCG overestimated blood glucose concentrations in goats, compared to the HITA, but when the POCG concentrations were corrected, the agreement was excellent.     

Effect of low‐ or high‐CP diet with cold‐pressed oil supplementation on growth,immunity and antioxidant indices of growing quail

This study was to investigate the effect of dietary protein levels and supplementation with two cold‐pressed oils on the performance, immunity and antioxidant indices of growing Japanese quails. A 3 × 4 factorial experiment, using 3 dietary crude protein (CP) levels (22%, 24% and 26%) and 4 supplemental herbal oils levels: control without additives, 250 mg marjoram (Mar), 250 mg thyme (Thy) and 125 mg Mar + 125 mg Thy per kg diet. A total of 720 unsexed, 7‐day‐old quail chicks were randomly distributed into twelve treatment groups (4 replicates per group of 15 chicks in each). The live body weight (LBW) on 42 days and body weight gain (BWG) from 7 to 42 days were significantly improved (p < 0.01 and 0.05) in chicks fed 24% or 26% CP compared with those of the 22% CP group. The groups fed diets supplemented with Mar or in combination with Thy oil exhibited significantly better LBW, BWG and feed conversion ratio (FCR) than the control at all periods except BWG from 21 to 42 days and FCR from 7 to 21 days were not significant. Feed intake was gradually decreased with increasing dietary CP level or adding herbal oils during the periods 21–42 and 7–42 days of age. Plasma triglycerides, cholesterol, total lipids and malondialdehyde were decreased by cold‐pressed oils supplementation, but the activity of reduced glutathione and superoxide dismutase was increased (p < 0.01) compared with the control. In conclusion, quails fed a diet containing 24% or 26% CP or diets supplemented with Mar or Thy oils or both exhibited improvement in the performance, lipid profile, immunity and antioxidant capacity without any detrimental impacts on the other studied parameters.     

Decreased blood cell counts were not observed in cattle living in the “difficult‐to‐return zone” of the Fukushima nuclear accident

White blood cells, especially lymphocytes, are susceptible to radiation exposure. In the present study, red blood cell, total white blood cell, and lymphocyte counts were repeatedly measured in cattle living on three farms located in the “difficult‐to‐return zone” of the Fukushima nuclear accident, and compared with two control groups from unaffected areas. Blood cell counts differed significantly between the two control groups, although almost all the values fell within the normal range. The blood cell counts of the cattle in the “difficult‐to‐return zone” varied across sampling times even on the same farms, being sometimes higher or lower than either of the two control groups. However, neither a statistically significant decrease in blood cell counts nor an increase in the rate of cattle with extremely low blood cell counts was observed overall. The estimated cumulative exposure dose for the cattle on the most contaminated farm was within a range of 500–1000 mSv, exceeding the threshold for the lymphopenia. Because of the low dose rate on these farms, potential radiation damages would have been repaired and have not accumulated enough to cause deterministic effects.     

Effects of dietary n‐6/n‐3 fatty acid ratio on nutrient digestibility and blood metabolites of Hanwoo heifers

The objectives of this study were to investigate the effects of dietary n‐6/n‐3 fatty acid (FA) ratio on digestibility, blood metabolites and FA profile of Hanwoo heifers. Fifteen Hanwoo heifers (22 ± 3 months old; 357 ± 69.7 kg) were randomly assigned to three dietary treatments with n‐6/n‐3 FA ratios of 2.07, 5.18 and 7.37. The animals were housed individually in digestion crates and fed total mixed rations at 2.2% of body weight for 2 weeks of adaptation and 1 week of collection. Treatment effects on in vivo digestibility, plasma metabolite and fatty acid profiles, and in vitro ruminal fermentation and fatty acid profiles were examined. In vivo digestibility was not affected (P > 0.05) by dietary n‐6/n‐3 FA ratio. However, in vitro dry matter digestibility and concentrations of total volatile fatty acids and propionate decreased (P < 0.05) linearly with increasing n‐6/n‐3 FA ratio. Plasma insulin and progesterone increased linearly (P < 0.05), but linolenic acid and total n‐3 FA decreased linearly (P < 0.05) with increasing n‐6/n‐3 ratio. Increasing the dietary n‐6/n‐3 FA ratio can increase the n‐6/n‐3 FA ratio in plasma and ruminal fluid as well as plasma progesterone secretion.     

Differences in rumen fermentation characteristics between low‐yield and high‐yield dairy cows in early lactation

Relationship between rumen fermentation parameters, blood biochemical profiles and milk production traits in different yielding dairy cows during early lactation was investigated. Twelve dairy cows were divided into two groups based on their milk yield, that is low‐yield (LY) and high‐yield (HY) groups. Rumen fluid and blood were collected at 3 weeks prepartum and 4, 8 and 12 weeks postpartum. Results showed that proportions of acetate, propionate to total short chain fatty acids and acetate : propionate ratio were changed (P < 0.05) in both groups during the peripartum period, whereas butyrate and acetate : butyrate ratio were only altered in the HY group. Blood cholesterol, beta‐hydroxybutyric acid (BHBA) and glutamic oxaloacetic transaminase in the HY group were higher (P < 0.01) than those in the LY group. Principal component analysis revealed that milk yield and milk compositions were differently clustered between groups. These parameters showed similar direction with dry matter intake in the HY group and adverse direction in the LY group. Linear regression analysis indicated that butyrate was positively correlated with BHBA (P < 0.05) in the HY group. This study suggests that cows in the HY group seem to accommodate appropriately to negative energy balance in early lactation through rumen fermentation.     

The use of lingual venous blood to determine the acid‐base and blood‐gas status of dogs under anesthesia

ObjectiveTo assess the suitability of lingual venous blood (LBG) as an alternative to arterial blood (ABG) samples in determining acid–base balance and blood–gas status in dogs anesthetized for elective procedures and with medetomidine and isoflurane administration under experimental conditions.Study designProspective, randomized clinical and experimental study.AnimalsClinical population of 18 ASA I/II dogs for elective surgery and five healthy Beagles (3 females and 2 males) for the experimental study.MethodsBlood sampling was simultaneously performed at dorsal pedal arterial and lingual venous sites, generating paired data. Two paired samples were collected from each dog in the clinical part and four from each dog in the experimental part (two during isoflurane anesthesia and two during isoflurane plus medetomidine). A modified Bland and Altman method was used to examine data from the clinical part and the experimental data were subjected to a paired sign's test following transformation where appropriate.ResultsThe pH of LBG overestimated ABG, with limits of agreement of (?0.01, 0.02). The partial pressure of carbon dioxide (PCO₂) of LBG overestimated ABG by 0.6 mmHg [0.1 kPa], with limits of agreement of (?3.5, 4.6) mmHg [?0.5, 0.6 kPa]. The partial pressure of oxygen (PO₂) of LBG underestimated ABG by 86.3 mmHg [?11.5 kPa], with limits of agreement of (?199.8, 27.3) mmHg [?26.6, 3.6 kPa]. During medetomidine administration values for PO₂ (p = 0.03) and lactate (p = 0.03) were lower for LBG when compared with ABG. The LBG value of PO₂ was lower (p = 0.03) during medetomidine and isoflurane administration versus isoflurane alone.Conclusions and clinical relevanceThe pH and PCO₂ of LBG samples provide clinically acceptable substitutes of ABG samples in the dog population studied. The wider limits of agreement for PO₂ render it less reliable as a substitute for ABG. The difference in PO₂ identified between LBG and ABG during medetomidine administration may not preclude the use of LBG as substitutes for ABG samples.     

Haematological and febrile response to Escherichia coli lipopolysaccharide in 12‐week‐old cockerels of genetically diverse layer lines fed diets with increasing L‐arginine levels

Due to its decisive function in the avian metabolic, endocrine and immune system L‐arginine (Arg) is dietary indispensable for chickens. In 12‐week‐old cockerels of two high‐ and two low‐performing purebred layer lines, the effects of increasing dietary Arg on the haematological and febrile response were studied over 48 h after single lipopolysaccharide (LPS) injection. The offered diets contained Arg equivalent to 70%, 100% and 200% of recommended supply. Pathophysiological alterations in weight gain, feed intake, body temperature and differential blood count were examined in comparison with their physiological initial values. Within the first 24 h after LPS injection, cockerels reduced feed intake and lost body weight subsequently. Thereby, low‐performing genotypes lost body weight to a lesser extent than high‐performing ones. The loss of body weight was further intensified by deficient dietary Arg. Within the following 24 h, cockerels recovered by improving feed intake and weight gain. Furthermore, LPS induced genotype‐specific fever response: both brown genotypes showed initial hypothermia followed by longer lasting moderate hyperthermia, whereas the white genotypes exhibited biphasic hyperthermia. Fever response was accompanied by significant changes in differential blood counts. Characterized by lymphopenia and heterophilia, a severe leucopenia was observed from 4 to 8 h after LPS injection and replaced by a marked leucocytosis with longer lasting monocytosis up to 48 h after LPS injection. Under given pathophysiological conditions, deficiently Arg‐supplied cockerels showed higher total leucocyte counts than adequately and excessively Arg‐supplied cockerels. However, deficient and surplus dietary Arg tended to cause higher ratios between heterophils and lymphocytes. To conclude, present results confirmed that LPS induced numerous immunological changes in 12‐week‐old cockerels and emphasized that chicken's genotype is a source of variation to be considered for immunological studies. Deficient dietary Arg intensified acute changes in differential blood counts and weight gain during LPS‐induced inflammation.     

Presumed immune‐mediated hemolytic anemia in two foals with Rhodococcus equi infection

Objective – To describe the clinical presentation, case management, and outcome in 2 foals with Rhodococcus equi infection associated with presumptive severe immune‐mediated hemolytic anemia. Series Summary – Two foals diagnosed with R. equi pneumonia on the basis of tracheal wash cultures, thoracic radiographs, and thoracic ultrasonography were concurrently diagnosed with hemolytic anemia. Both foals required whole blood transfusions, and were treated with the antimicrobial combination of rifampin and a macrolide (eg, clarithromycin, erythromycin, or azithromycin). Dexamethasone was used to prevent further hemolysis in both foals, and to treat acute lung injury/acute respiratory distress syndrome in 1 of the foals. Both foals survived, and required prolonged antimicrobial therapy. New or Unique Information Provided – Although extra‐pulmonary disorders are commonly diagnosed in foals infected with R. equi, hemolytic anemia is rarely described. Dexamethasone is considered the treatment of choice for immune‐mediated hemolytic anemia, but may be contra‐indicated in foals with severe bacterial infections. In these foals, a relatively low dose and short duration of dexamethasone was utilized in an attempt to minimize immune suppression, although early discontinuation in 1 foal precipitated a second hemolytic crisis.     

Intra‐ovarian dynamic blood flow in pseudopregnant rabbits during prostaglandin F2α‐induced luteolysis

In the present study, we evaluated the dynamic changes of intra‐ovarian blood flow, by real‐time colour‐coded and pulsed Doppler ultrasonography, as well as the immunopresence of prostaglandin F2α (PGF2α) receptor (FP) and peripheral plasma progesterone concentrations in pseudopregnant rabbit after PGF2α treatments at either early‐ (4 days) and mid‐luteal (9 days) stages. During the pre‐treatment observation interval of one hour, the ovarian blood flows showed a fluctuating pattern. Independently of luteal stage, PGF2α administration caused a fourfold decline in the blood flow within 40 min that was followed 50 min later by a reactive hyperaemia that lasted several hours, while the resistive index showed an opposite trend. Twenty‐four hour later, the blood flow was one half that measured before PGF2α injection. At day 4 of pseudopregnancy, PGF2α did not affect peripheral plasma progesterone concentrations, but at day 9, it caused functional luteolysis as progesterone levels declined 6 hr later to reach basal values after 24 hr. The changes in the ovarian blood flows of pseudopregnant rabbits receiving PGF2α were accompanied by simultaneous changes in the resistance index. This biphasic response in the blood flow and vascular resistances likely reflects reactive hyperaemia following vasoconstriction. By immunohistochemistry, strong positive immune reaction for FP was detected in the cytoplasm of endothelial cells of ovarian arteries, veins and capillaries. In conclusion, these results suggest that PGF2α could acutely regulate the ovarian blood flow of pseudopregnant rabbits, even if there is no evidence of a blood flow reduction anticipating luteolysis.     

Noncitrated blood transfusions used as adjunctive treatment in a 7‐year‐old Shetland Pony with haemoperitoneum due to a ruptured corpus haemorrhagicum

Chronic bleeding due to extensive haemorrhage from a ruptured corpus haemorrhagicum developed 2–4 weeks after parturition and was identified as the cause for a haemoperitoneum in a 7‐year‐old Shetland Pony mare, leading to anaemia. Diagnosis was made upon exploratory coeliotomy and a unilateral ovariectomy was performed. Intra‐ and post operatively, the mare received autologous blood transfusions of noncitrated blood. To our knowledge, this is the first report of an autologous blood transfusion accomplished using noncitrated blood collected from the abdominal cavity.