title: Energy balance in transition cows and its association with health, reproduction and milk production.
abstract: OBJECTIVE
  It was the purpose of this study to determine the effects of non-esterified fatty acids (NEFA) concentrations at different time periods of the transition period as well as lactation number on metabolism, health, reproduction and milk production in dairy cows.
  
  
  METHODS
  This trial was conducted in a single dairy herd located in Northern Germany. Of the herd, which comprised 330 lactating Holstein cows housed in a free stall barn and fed a total mixed ration (TMR), 83 primiparous and multiparous cows were randomly selected. Animals were checked for body condition score (BCS), locomotion score, calving data, quality of colostrum, reproductive measures, daily rectal temperature of the first 10 days post-partum (p. p.), health data and culling rates up to 200 days in milk (DIM) as well as milk production until 305 DIM. Three different time periods were considered: 3 and 1 week ante partum (a. p.); partus and 1 week p. p.; 3 weeks p. p.
  
  
  RESULTS
  Animals with NEFA concentrations ≥ 0.4 mmol/l ante partum had a higher risk of no ovarian activity in week 5 p. p. and of subclinical ketosis post partum than cows with lower NEFA concentrations (p < 0.05). Cows with NEFA concentrations ≥ 1.1 mmol/l in week 1 p. p., in comparison to those with lower NEFA concentrations, showed a higher prevalence of clinical ketosis (24.1% vs. 5.9%), subclinical ketosis (62.1% vs. 34.0%) and culling rate within 200 DIM (34.5% vs. 14.0%) (p    <   0.05). Cows with NEFA concentrations ≥ 0.3 mmol/l at week 3 p. p. had higher 100- and 305-day milk yields than cows with lower NEFA concentrations (p < 0.05). First lactating heifers were at higher risk to loose body condition ante partum, of dystocia, fever within the first 10 DIM, metritis, clinical and subclinical ketosis as well as to develop a disease within the first 30 DIM (p < 0.05). Multipara were more likely to loose body condition after calving, to a prolonged calving to first service interval and to higher milk yields (p < 0.05).
  
  
  CONCLUSIONS
  In conclusion increased NEFA concentrations during the transition period as well as parity can have an influence on health, production and reproduction of dairy cows.
authors.affiliation: Cora Furken, Klinik für Rinder, Stiftung Tierärztliche Hochschule Hannover, Bischofsholer Damm 15, 30173 Hannover, Email: corafurken@web.de.
authors.forename: C
authors.initials: C
authors.lastname: Furken
authors.forename: T
authors.initials: T
authors.lastname: Nakao
authors.forename: M
authors.initials: M
authors.lastname: Hoedemaker
mesh_terms: D000824:Animal Nutritional Physiological Phenomena; D000818:Animals; D002417:Cattle / Q000097:blood / Q000502:physiology*; D002418:Cattle Diseases / Q000503:physiopathology; D003612:Dairying / Q000379:methods; D005230:Fatty Acids, Nonesterified / Q000097:blood*; D005260:Female; D007662:Ketosis / Q000503:physiopathology / Q000662:veterinary; D007774:Lactation / Q000502:physiology*; D008892:Milk / Q000502:physiology; D012098:Reproduction / Q000502:physiology*
chemical_list: D005230:Fatty Acids, Nonesterified
keywords: Health; NEFA; metabolism; reproduction; transition dairy cows