Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
Preliminary results of a metabolic survey for plasma ionized Calcium and Magnesium in dairy herds from the south of Chile
Melendez, P.; Lopez, F.; Lama, J...
Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
Read
Ionized calcium is the biologically active form of calcium; therefore, total calcium might not be the best indicator for hypocalcemia in dairy cows because of the changes in blood pH and protein concentrations. Consequently, the objective of this study was to determine the concentration of plasma ionized calcium and magnesium in cows at parturition from representative dairy herds from the south of Chile. The study was conducted in the southern region of Chile covering an area of 20,544 km2 (214 km length, 96 km wide; -39.82 S, -73.23 W; -40.12 S, - 72.38 W; -41.39 S, -73.46 W; -41.43 S, -72.94 W).
Mean temperature during autumn is 7°C while during spring is 10°C, while mean rainfall during autumn is 850 mm, but in spring is only 150 mm. The study consisted of selecting at random 11 dairy herds from a pool of 100 herds and sampling 8 cows per herd during the first 12 hours after parturition. All herds were handled under grazing conditions and had a calving distribution of 30% in autumn/winter, and 70% in spring/summer. Herds consisted of Holstein cows (Australian, New Zealand, Europe, and US genetics), artificial insemination breeding, and milked twice a day. Predominant pasture was based on perennial ryegrass (Lolium perenne). Spring calvings received 70% of dry matter from pasture and the rest from a partial mixed ration previous to each milking and concentrate in the milking parlor.
Between August and December 2019, a blood sample for plasma collection was taken from a total of 88 cows from the 11 herds. Samples were stored in a cooler and shipped during the same day to a certified veterinary clinical pathology lab (Cooprinsem, Osorno, Chile). Samples were centrifuged and plasma was stored in plastic vials and frozen at -20 °C until analysis. Samples were assessed for ionized Ca and Mg using the Stat Profile® PRIME Plus VET (Nova Biomedical Corporation, Waltham, MA 02454-9141 USA). From the total samples, 26.7% were from parity 1, 19.6% parity 2 and 53.6% parity 3 or more.
Total mean ionized Ca concentration was 1.00 mmol/L (range: 0.54-1.24 mmol/L) and ionized Mg was 0.615 mmol/L (range=0.32 – 0.89 mmol/L). Within parity number, the concentration of ionized Ca was 1.064, 1.024, and 0.894 mmol/L for parity 1, 2, and ≥3, respectively. For ionized Mg was 0.63, 0.60, and 0.613 mmol/L, for parity 1, 2, and ≥ 3, respectively. Defining a cut-off value of ionized Ca for subclinical hypocalcemia of 1.10 mmol/L, the total prevalence of subclinical hypocalcemia at day 1 postpartum was 65% with a range of an intra-herd prevalence between 0% and 100%. From the total number of cows (n=88), the prevalence of subclinical hypocalcemia within parity number was 40%, 54.5%, and 86.7% for parity 1, 2, and ≥ 3, respectively. It is concluded that subclinical hypocalcemia based on ionized Ca determination, is a metabolic disorder more common than expected in Chilean southern dairy cattle handled under grazing conditions.
Keywords: Ionized calcium, ionized magnesium, dairy herds, Chile.
Get access to all handy features included in the IVIS website
- Get unlimited access to books, proceedings and journals.
- Get access to a global catalogue of meetings, on-site and online courses, webinars and educational videos.
- Bookmark your favorite articles in My Library for future reading.
- Save future meetings and courses in My Calendar and My e-Learning.
- Ask authors questions and read what others have to say.
About
Affiliation of the authors at the time of publication
University of Georgia, Tifton, United States;
Austral University of Chile, Valdivia, Chile;
Cooprinsem, Osorno, Chile;
Colorado State University, Fort Collins, United States.
Comments (0)
Ask the author
0 comments