Comparison of prepartum blood parameters in dairy cows with postpartum ketosis and new risk prediction candidates.

Introduction: Ketosis is a predominant metabolic problem and a risk factor for several postpartum diseases. This retrospective study aimed to evaluate the complete blood count (CBC), plasma biochemistry, and osteocalcin and identify significant prepartum and early postpartum values expressed in ketotic cows. Methods: In 135 Holstein Friesian cows, 210 parturitions of 114 primiparous and 96 multiparous cows were examined. According to the plasma concentrations of ß-hydroxybutyrate (BHB; ≥ 1.4 mmol/L) or non-esterified fatty acids (NEFA; ≥ 0.7 mmol/L) in the postpartum period, cows were divided into healthy cows (CON) and ketotic cows (KET). Analyses of CBC and biochemistry profiles were performed from -6 to 4 weeks of parturition every 2 weeks (prepartum; BW-5, BW-3, and BW-1, postpartum; BW1 and BW3), and osteocalcin ELISA tests were performed using blood samples from -2 to 2 weeks of parturition (BW-1 and BW1). Results: In primiparous KET (n = 114) before parturition, lower lymphocyte (Lym) in BW-5 and BW-3, lower red blood cell (RBC) in BW-5, higher mean corpuscular volume (MCV) in BW-1, and higher NEFA in BW-3 were significant compared with CON. Primiparous KET showed lower carboxylated osteocalcin (cOC) levels and a significant decrease after parturition. In multiparous KET (n = 96) before parturition, lower neutrophil (Neu) in BW-5, higher hemoglobin (HGB) in BW-5, higher MCV in BW-5 and BW-1, higher MCH in BW-5, lower total cholesterol (TC) in BW-5, higher triglyceride (TG) in BW-3, higher NEFA in BW-1, higher glucose (Glu) in BW-3, lower γ-glutamyl transferase (GGT) in BW-5, lower inorganic phosphate (iP) in BW-3, and higher body condition score (BCS) in BW-5 and BW-3 were significant compared with CON. Multiparous KET showed decreased cOC and uncarboxylated osteocalcin (ucOC) after parturition, which was lower than that in the CON group. Discussion: The blood parameters expressing different values between CON and KET in prepartum or early postpartum periods are presumed to show individual nutrition and health states, liver function, and overweight status. These parameters could be valuable indicators that can be used to prevent the occurrence of ketosis and improve management practices by recognizing these differences in ketotic cows before calving.

Evaluation of Corpus Luteum and Plasma Progesterone the Day before Embryo Transfer as an Index for Recipient Selection in Dairy Cows.

The aim of the present study was to evaluate the effects of synchronization method, season, parity, corpus luteum (CL) size, and progesterone (P4) levels on the pregnancy rate after bovine embryo transfer (ET). Among 165 recipient candidates who received 1 of 2s estrus synchronization treatments, 96 heifers and 43 cows were selected through rectal examination and used as recipients. The day before ET, the CL size and plasma P4 concentration were evaluated. The CL sizes and plasma P4 levels were not different between the selected and unselected candidates, and the pregnancy rates with the two synchronization methods were not different. However, the pregnancy rates were higher in heifers than in lactating cows, and also higher after ET performed from September to February than from March to August (p < 0.05). The recipients with a CL larger than 1.5 cm showed statistically higher pregnancy rates, and although there was no statistical significance, the pregnancy rate was higher when the plasma P4 levels were between 2.0 and 4.0 ng/mL. Exposure to a stressful environment and repeated manipulations can reduce the success rate of ET, and recipient selection with an optimal CL size and P4 level can increase the success rate of ET.

Comparison of the bovine blood gas parameters produced with three types of portable blood gas analyzers.

BACKGROUND: A definite diagnosis should be made in the bovine practice field, however, it was difficult to perform laboratory analysis immediately. Currently, three types of portable blood gas analyzers are available in Korea. OBJECTIVES: This study aimed to evaluate the correlations among these three analyzers. METHODS: Seventy-two plasma samples from Holstein-Friesian cows were used for blood gas analysis, and three instruments (EDAN i15 Vet, VETSCAN i-STAT, and EPOC) were operated simultaneously. Moreover, plasma calcium levels were compared between these portable analyzers and blood chemistry device, which is usually used in a laboratory environment. Pearson analysis was performed to confirm the correlation of each parameter produced with the three instruments and blood chemistry analyzer. RESULTS: As results, high correlation was observed in parameters of pH, pO2, potassium ion, ionized calcium, and glucose (p < 0.001, r > 0.7). In addition, pCO2 showed a moderate correlation among the three analyzers (p < 0.001, r > 0.5), and there was no correlation among all instruments for sodium ions. There was also a high correlation between ionized calcium from the three portable devices and total calcium from the biochemistry analyzer (p < 0.001, r > 0.9). CONCLUSIONS: In conclusion, there was a high correlation between results from the three different blood gas analyzers used in the bovine clinical field in Korea. Thus, a consistent diagnosis can be made even with different equipment if the operator is aware of the strengths and weaknesses of each piece of equipment and operates it properly.

Spontaneous Alteration of Blood pH By a Bicarbonate Buffer System During Experimental Hypercalcaemia in Cows.

INTRODUCTION: Maintaining mineral homeostasis as well as the secretion and metabolism of mineralotropic hormones is important for healthy of periparturient dairy cows. To increase the activity of mineralotropic hormones, blood pH can be adjusted. The purpose of this study was to investigate changes in blood pH and the mechanism of action of this change in induced hypercalcaemic cows. MATERIAL AND METHODS: Six non-lactating Holstein cows were used in a 2 × 2 crossover design. To induce hypercalcaemia, calcium borogluconate was administered subcutaneously to experimental cows and normal saline was administered subcutaneously to control cows. Blood and urine samples were collected serially after administration. Whole blood without any anticoagulant was processed with a portable blood gas analyser. Plasma concentration and urinary excretion of calcium were measured. RESULTS: In hypercalcaemic cows, both blood and urine calcium levels were significantly increased at 8 h compared to those at 0 h (P < 0.05), and a spontaneous increase in blood pH was also observed. The calcium concentration in plasma was highest at 2 h after administration (3.02 ± 0.27 mmol/L). The change in pH correlated with that in bicarbonate (r = 0.781, P < 0.001) rather than that in partial pressure of CO2 (r = 0.085, P = 0.424). CONCLUSION: Hypercalcaemia induced a spontaneous change in blood pH through the bicarbonate buffer system and this system may be a maintainer of calcium homeostasis.

Changes in plasma pH and blood and urinary macromineral concentrations in experimentally induced hypocalcemic cows with Na2EDTA.

This study was performed to confirm the alterations of blood and urine parameters in artificially induced hypocalcemic cows. For a 2 × 2 cross-over design, four non-pregnant, non-lactating Holstein Friesian cows (623 ± 63 kg) were utilized. Cows in the treatment and control group were infused with ethylenediaminetetraacetic acid (Na2EDTA) solution and normal saline through an intravenous catheter for 3 hr, respectively. Laboratory analyses included complete blood cell count, plasma chemistry, blood gas analysis and urine chemistry. During the hypocalcemic period, abnormal signs were not observed clinically, hematologically nor biochemically either in groups. But, plasma calcium and magnesium concentrations continued to decrease throughout Na2EDTA infusion, and significant group differences (P<0.05 or P<0.001) were detected until 5 hr after the initiation of infusion. Urinary excretions of these minerals were significantly reduced compared to the control group by 6 hr (Ca, P<0.05; Mg, P<0.001). Moreover, there is a significant group difference in the change in plasma pH at 1 hr after Na2EDTA infusion (P<0.05) and maintained a decreased level until 6 hr. Consequently, the blood pH was diminished simultaneously with hypocalcemia and hypomagnesemia induction in cows infused with Na2EDTA. This phenomenon may be one of the mechanisms to recover normocalcemia including maximizing the effect of parathyroid hormone, however, further studies are needed to elucidate the mechanism to alter the blood pH in hypocalcemia.