Metabolic and endocrine adaptations to support milk production during the transition period vary between individual cows. This variation between cows to adapt to lactation may have a genetic basis. The present field study was carried out to determine hepatic adaptations occurring from late pregnancy through early lactation by measuring mRNA abundance of candidate genes in dairy cows on-farm. Additionally, the objective was to observe the diversity in inter-individual variation for the candidate genes that may give indications where individual adaptations at a molecular level can be found. This study was carried out on-farm including 232 dairy cows (parity >3) from 64 farms in Switzerland. Blood and liver samples were collected on d 20±7 before parturition, on d 24±2, and on d 89±4 after parturition. Blood plasma was assayed for concentrations of glucose, nonesterified fatty acids, β-hydroxybutyrate, cholesterol, triglycerides, urea, albumin, protein, insulin, insulin-like growth factor-1, leptin, 3,5,3'-triiodothyronine, and thyroxine. Liver samples were obtained at the same time points and were measured for mRNA abundance of 26 candidate genes encoding enzymes and nuclear receptors involved in gluconeogenesis, fatty acid β-oxidation, fatty acid and triglyceride synthesis, ketogenesis, citric acid cycle, cholesterol synthesis, and the urea cycle. The cows in the present study experienced a marked metabolic load in early lactation, as presented by changes in plasma metabolites and hormones, and responded accordingly with upregulation and downregulation of almost all candidate genes involved in metabolic processes in the liver. The observed inter-individual variation for the candidate genes, which was highest for acetyl-CoA-carboxylase and glycerol-3-phosphate dehydrogenase 2, should be further investigated to unravel the regulation at molecular level for optimal adaptive performance in dairy cows.
Prevalences of foot lesions and lameness were recorded in 1'449 Swiss dairy cows during routine claw-trimming on 78 farms from June 2010 until February 2011. Lameness was present in 14.8 % of cows and on 80.8 % of investigated farms. Highest prevalences were seen for widened white line (80.7 %/100 %), signalling foot lesion (65.6 %/98.7 %), heel-horn erosion (34.2 %/88.5 %), digital dermatitis complex (29.1 %/73.1 %), severe hemorrhages (27.9 %/87.2 %), and Rusterholz' sole ulcers (11.5 %/74.4 %) at cow and herd level, respectively. Lower prevalences were found for subclinical laminitis (5.4 %/47.4 %), chronic laminitis (3.3 %/25.6 %), white line disease (4.7 %/42.3 %), double soles (2.6 %/33.3 %), interdigital hyperplasia (3.1 %/33.3 %), sole ulcers (0.4 %/6.4 %), toe infections caused by faulty claw-trimming (3.9 %/39.7 %) and by injury (0.1 %/2.6 %), deep lacerations (0.4 %/6.4 %), and interdigital phlegmona (0.1 %/1.3 %). Lameness and foot lesions were shown to represent important health problems of dairy cows under the conditions of the typical grass-based production system in Switzerland. Digital dermatitis has developed to the most relevant foot disease with a high impact on welfare of Swiss dairy cows within the past 10 years.
Blood plasma and hepatic parameters were identified that describe the differences between metabolically robust or vulnerable dairy cows grouped according to their past health status. Data from a field study on dairy cows were used from which metabolically challenged dairy cows were selected that had a milk fat percentage of >4.5 mg/g and a fat to protein ratio of >1.5 in their previous early lactation. The selected cows were either classified as metabolically robust or vulnerable based on the occurrence of various metabolic and (re)production disorders in their previous lactations. Blood and liver tissue samples were collected in week 3 ante partum (a.p.) (-3 wk), in week 4 (+4 wk) and in week 13 (+13 wk) post-partum (p.p.). Plasma concentrations of metabolites and hormones and mRNA expression of genes involved in metabolic pathways in the liver were used as variables for a two-group discriminant analysis (DA). Average discriminant scores (centroids) were different (p < 0.05) in -3 wk, +4 wk and in +13 wk. In -3 wk, significant variables that best explained the differences between metabolically robust and vulnerable cows were parity, plasma triglycerides, glucose and mRNA abundance of carnitine palmitoyltransferase 2 (CPT2). In addition, based on the classification matrix, 69% of the dairy cows were correctly classified. In +4 wk, identified significant parameters were parity, plasma glucose and urea, and 67% of the cows were correctly classified. In +13 wk, significant variables that explained the differences between the groups were parity, mRNA abundance of acyl-CoA synthetase long-chain 1 and CPT1, and 66% of the cows were correctly classified. In conclusion, the identified variables may distinguish from metabolically challenged cows, those cows that had a poorer health performance in their previous lactations.
The objective of this study was to evaluate risk factors associated with foot lesions and lameness in Swiss dairy cows. Potential risk factors were recorded by means of examination of 1'449 Swiss cows and the management systems of 78 farms during routine claw-trimming, and during personal interviews with the associated farmers. Statistical analysis of animal-based and herd level risk factors were performed using multivariate logistic regression models. The risk of being lame was increased in cows affected by digital dermatitis complex, heel-horn erosion, interdigital hyperplasia, Rusterholz' sole ulcer, deep laceration, double sole and severe hemorrhages. Cleanliness, BCS, affection with other foot lesions, breed, importance of claw health to the farmer, frequency of routine claw-trimming, producing according to the guidelines of the welfare label program RAUS, and silage feeding were shown to be associated with the occurrence of some of the evaluated foot lesions and lameness. The identified risk factors may help to improve management and the situation of lameness and claw health in dairy cows in Switzerland and other alpine areas with similar housing and pasturing systems.
BackgroundProphylactic measures are key components of dairy herd mastitis control programs, but some are only relevant in specific housing systems. To assess the association between management practices and mastitis incidence, data collected in 2011 by a survey among 979 randomly selected Swiss dairy farms, and information from the regular test day recordings from 680 of these farms was analyzed.ResultsThe median incidence of farmer-reported clinical mastitis (ICM) was 11.6 (mean 14.7) cases per 100 cows per year. The median annual proportion of milk samples with a composite somatic cell count (PSCC) above 200,000 cells/ml was 16.1 (mean 17.3) %. A multivariable negative binomial regression model was fitted for each of the mastitis indicators for farms with tie-stall and free-stall housing systems separately to study the effect of other (than housing system) management practices on the ICM and PSCC events (above 200,000 cells/ml). The results differed substantially by housing system and outcome. In tie-stall systems, clinical mastitis incidence was mainly affected by region (mountainous production zone; incidence rate ratio (IRR) = 0.73), the dairy herd replacement system (1.27) and farmers age (0.81). The proportion of high SCC was mainly associated with dry cow udder controls (IRR = 0.67), clean bedding material at calving (IRR = 1.72), using total merit values to select bulls (IRR = 1.57) and body condition scoring (IRR = 0.74). In free-stall systems, the IRR for clinical mastitis was mainly associated with stall climate/temperature (IRR = 1.65), comfort mats as resting surface (IRR = 0.75) and when no feed analysis was carried out (IRR = 1.18). The proportion of high SSC was only associated with hand and arm cleaning after calving (IRR = 0.81) and beef producing value to select bulls (IRR = 0.66).ConclusionsThere were substantial differences in identified risk factors in the four models. Some of the factors were in agreement with the reported literature while others were not. This highlights the multifactorial nature of the disease and the differences in the risks for both mastitis manifestations. Attempting to understand these multifactorial associations for mastitis within larger management groups continues to play an important role in mastitis control programs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.