Effects of increasing days of exposure to prepartum diets on the concentration of certain blood metabolites in dairy cows

Implementation of hypocalcaemia prevention programmes in commercial dairy herds: From theory to practice

Hypocalcaemia prevention programmes have been widely studied in experimental settings, but their feasibility has not been assessed under field conditions. The main objective of this study was to evaluate, in the context of small dairy farms in western France, whether and how dairy farmers implement prevention programmes and manage the feeding of dry cows to prevent hypocalcaemia. Seventy-nine commercial Holstein dairy farms in Brittany (France) were enrolled in a qualitative study in 2019. We conducted in-person interviews with the farmers to 1) understand the rationale behind the type and seasonality of prevention programmes they implemented and 2) assess how closely they followed common recommendations when implementing them. Most farmers (80 %) used at least one prevention programme, especially supplying a mineral mix formulated to meet the needs of dry cows in late gestation (53 %), acidifying the diet in late gestation (37 %), and supplying calcium at calving (oral or injectable form, 37 %). The use of programmes depended on whether the diet composition varied throughout the year. Among farmers who provided an acidified diet, 25 % did not supply a specific mineral mix to dry cows to ensure an adequate amount of P, Ca, and Mg, which could decrease the effectiveness of the acidification programme. A lack of reliability in feeding practices, such as not weighing feed or not delivering feed frequently enough, was identified for 61 % of contributing farms. Management practices could result in supplying an unsuitable amount of P, Ca, or Mg immediately before calving; for example, inappropriate batching practices around calving were identified for 22 % (cows) to 32 % (heifers) of farms. In addition, nearly all contributing farmers had no processes in place to monitor the effectiveness of the programmes implemented. Reasons for this overall lack of compliance should be explored.

Associations between days on close-up diets and immune responses prepartum, metabolites peripartum, and risk of postpartum diseases in Jersey cows

Nutritional strategies during the final weeks prepartum, the close-up period, aim to reduce immune suppression and metabolic imbalances. This paper reports results of 2 observational studies. Data from 2 previous experiments (study 1) were used to investigate the associations between days fed close-up diets (DINCUD) and uterine diseases (n = 1,230). In study 2, retrospective data from animals not used in study 1 (n = 11,962) were used to investigate the associations between DINCUD and removal from the herd and long-term reproductive and productive responses. Nulliparous (lactation = 0) and parous (lactation ≥1) cows were moved to close-up pens 28 d before expected calving date, but only parous cows were fed rations with negative dietary cation-anion difference. In study 1, study personnel diagnosed retained fetal membranes, metritis, and acute metritis postpartum. Length of the close-up period was tested for its linear and quadratic effects. The β-coefficients from the multivariable analyses were used to calculate the predicted outcome for each cow. In addition, the mean (±SEM) for cows with <10, 28 ± 3, and 42 ± 3 DINCUD are reported. Metritis was associated with the interaction between DINCUD and parity-diet (nulliparous: <10 d = 31.8 ± 9.2, 28 ± 3 d = 21.8 ± 0.7, 42 ± 3 d = 29.8 ± 2.1%; parous: <10 d = 81.7 ± 2.9, 28 ± 3 d = 11.1 ± 0.3, 42 ± 3 d = 14.8 ± 1.3%). The interaction between DINCUD and parity-diet was associated with total energy-corrected milk yield (nulliparous: ≤10 d = 7.91 ± 0.03, 28 ± 3 d = 8.17 ± 0.01, 42 ± 3 d = 8.15 ± 0.01 kg × 10³; parous: ≤10 d = 7.99 ± 0.05, 28 ± 3 d = 9.79 ± 0.01, 42 ± 3 d = 9.52 ± 0.03 kg × 10³) and percentage of cows pregnant by 305 days in milk (DIM; nulliparous: ≤10 d = 80.4 ± 0.4, 28 ± 3 d = 83.3 ± 0.1, 42 ± 3 d = 82.8 ± 0.2%; parous: ≤10 d = 59.5 ± 0.7, 28 ± 3 d = 78.3 ± 0.1, 42 ± 3 d = 73.1 ± 0.5%). Furthermore, the interaction between DINCUD and parity-diet was associated with removal from the herd by 305 DIM (nulliparous: ≤10 d = 27.0 ± 0.5, 28 ± 3 d = 20.7 ± 0.1, 42 ± 3 d = 21.8 ± 0.1%; parous: ≤10 d = 45.1 ± 0.7, 28 ± 3 d = 31.1 ± 0.1, 42 ± 3 d = 28.1 ± 0.3%). Jersey cows that are managed to achieve 28 DINCUD may have reduced odds of uterine diseases and improved reproductive and productive performances.

Clinical and Biochemical Profile of Iraqi Local Breed Cows During Pregnancy and Early Lactation

This study was conducted in Al-Alam region, which is located in Salah Al-Din Governorate, on first month pregnant Iraqi local cows (n-10). The follow up extended from the first month of pregnancy up to the end of the first month post-parturition during that some clinical and biochemical parameters were measured in the serum. Blood samples from the jugular vein of cows were collected monthly for the whole period of experiment and divided into four stages: early pregnancy, mid pregnancy, late pregnancy, and early lactation immediately after birth. It was observed that the temperature, respiration rate, and heart rate increased gradually and significantly (P≤0.05) with the progress of pregnancy reaching to its highest value in the last period of pregnancy and decreased after birth. The last trimester of pregnancy and the early lactation were also showed a significant decrease (P≤0.05) of the phosphorus, calcium, iron, and copper concentrations compared to the first and second trimesters of the pregnancy however, significant increases in other biochemical values (P≤0.05) were observed in urea and creatinine concentrations in the last trimester of pregnancy and early lactation. In addition to a significant decrease (P≤0.05) of the ratios of concentrations of glucose, total protein, albumin, and globulin in the last period of pregnancy compared to other periods. The decrease in the value of globulin continued until the early birth period while the study did not show any significant difference in the concentration of bilirubin between durations. Finally, values of the ALT, AST and ALP enzymes showed significant increases (P≤0.05) in their concentrations in the last period of pregnancy. It is concluded that possible changes in the biochemical parameters of the local Iraqi cows’ blood during pregnancy and early lactation are existed

Changes in the metabolic profiles of dairy cows before and after calving that were mainly fed fodder beet (Beta vulgaris vulgaris L.) during the dry period

Case history: Two commercial pasture-based farms within the North Canterbury district of New Zealand were feeding fodder beet (Beta vulgaris vulgaris L.) as a large proportion of the diet to cows during the dry period. On each farm 25 multiparous cows were blood sampled up to six times from 28 days before, to 21 days after calving (Day 0). Plasma samples were analysed for concentrations of β-hydroxybutyrate (BHBA), non-esterified fatty acid (NEFA), Ca, Mg and P, and aspartate aminotransferase (AST) activity. The first sampling visit was performed when cows were being fed their maximum intake of fodder beet. Clinical findings: The mean body condition score (BCS) of cows on Farm 1 was 5.4 (95% CI = 5.3-5.6) and on Farm 2, 5.4 (95% CI = 5.3-5.6) at first sampling. Mean concentrations of BHBA increased between Days -15 and Day -8 then decreased postpartum on Day 2 before increasing again on Day 21. On Farm 2, concentrations remained low (<1.2 mmol/L) on all days of sampling. Mean concentrations of NEFA in plasma remained low during the periparturient period on Farm 1, then increased on Day 2. On Farm 2, concentrations were elevated above 0.3 mmol/L between Days -28 and -17 then decreased on Day -10, before increasing on Day 2. Mean concentrations of Ca, Mg and P were higher than threshold values on both farms prepartum. However on Day 2, there were 8/23 (35%) cows on Farm 1 and 6/23 (26%) cows on Farm 2 with concentrations of Ca in plasma <2.0 mmol/L, and 10/23 (44%) cows on Farm 1 and 8/23 (35%) cows on Farm 2 with concentrations of P in plasma <1.3 mmol/L. Mean AST activities remained relatively constant and below 130 IU/L on both farms at all sampling times. Clinical relevance: On both farms, post-partum hypocalcaemia and hypophosphataemia were common after calving despite differing fodder beet feeding and mineral supplementation regimes. There was more variation in energy status, especially prior to calving. More research is required on factors affecting mineral and energy status in dry cows fed fodder beet.

Associations between bone and energy metabolism in cows fed diets differing in level of dietary cation-anion difference and supplemented with cholecalciferol or calcidiol

Bone-derived hormones play an important role in metabolism. This study examined the hypothesis that interactions between bone and energy metabolism, particularly those involving osteocalcin, are present in dairy cattle and have feedback mechanisms over time. Associations between metabolites in blood were examined in 32 Holstein cows blocked by parity and milk yield and randomly allocated to diets containing either 0.27 mg/kg dry matter (DM) calcidiol or cholecalciferol for an anticipated intake of 3 mg/d (120,000 IU/d) at 11 kg of DM, and positive (+130 mEq/kg DM) or negative (-130 mEq/kg DM) dietary cation-anion difference (DCAD) from 252 d of gestation to calving. Blood was sampled every 3 d, from 9 d prepartum to 30 d postpartum, and plasma concentrations of vitamin D₃, 25-hydroxyvitamin D₃, adiponectin, C-telopeptide of type 1 collagen (CTX1), glucose, insulin-like growth factor 1 (IGF1), insulin, undercarboxylated osteocalcin (uOC), and carboxylated osteocalcin (cOC) were determined. Feeding calcidiol compared with cholecalciferol increased plasma concentrations of 25-hydroxyvitamin D₃ pre- (264.2 ± 8.0 vs. 61.3 ± 8.0 ng/mL) and postpartum (170.8 ± 6.2 vs. 51.3 ± 6.2 ng/mL) but decreased concentrations of vitamin D₃ pre- (1.2 ± 0.6 vs. 14.5 ± 0.6 ng/mL) and postpartum (1.9 ± 0.4 vs. 3.2 ± 0.6 ng/mL). Prepartum, cows fed the negative DCAD diet had reduced concentrations of vitamin D₃ and glucose compared with cows fed a positive DCAD. The combination of negative DCAD and cholecalciferol reduced IGF1 concentrations prepartum. The DCAD treatment had no effect on postpartum concentrations of metabolites. Nulliparous cows had increased concentrations of OC, CTX1, IGF1, glucose, and insulin compared with parous cows. Time series analysis identified associations between metabolites on the same day and over 3-d lags up to ±9 d that suggest feedback between 25-hydroxyvitamin D₃ and vitamin D₃ in the negative lags, indicating that 25-hydroxyvitamin D₃ may exert feedback on vitamin D₃ but not vice versa. We found evidence of a feedback mechanism between vitamin D₃ and IGF1, with positive effect size (ES) on the same day and 3 d later, and negative ES 9 d later, that was more evident in cholecalciferol-fed cows. This suggests an important role of IGF1 in integrating bone metabolism with energy and protein metabolic pathways. Evidence of feedback was found between uOC and particularly cOC with IGF1, with positive ES on the same day but negative ES 6 d before and 6 d after. An association between uOC or cOC and IGF1 has not been previously identified in cattle and suggests that both uOC and cOC may have marked biological activity. Associations between OC and insulin identified in mice were not observed herein, although associations between OC and glucose were similar to those between IGF1 and glucose, supporting associations between glucose, OC, and IGF1. We provide further statistical evidence of crosstalk between vitamin D compounds, bone hormones, and energy metabolism in cattle. In particular, associations between uOC or cOC and IGF1 may provide links between prepartum diets and observations of prolonged increases in milk production and allow better control of peripartum metabolism.