ABSTRACT
INTRODUCTION: Especially in regions with intensive cattle farming, paratuberculosis in ruminants can cause considerable economic losses for example through loss of sick animals, reduced milk yield and decreased reproduction performance. Although quantifying the actual economic losses is complex, this study attempts to quantify the losses caused by paratuberculosis in infected dairy farms in Switzerland by means of meta-analyses. For this purpose, in an elaborate selection process, data from 12 studies on milk yield and from three studies on the calving to conception interval were finally selected for further calculations. In addition, data from eight studies each on milk fat concentration and milk protein concentration were evaluated. For the meta-analyses, only studies in which «sick¼ (seropositive) and «healthy¼ (seronegative) animals based on the results of serum ELISA tests were compared at the individual animal level were considered. With a paratuberculosis prevalence of 5,99 % in cattle in Switzerland, a total loss of CHF 12 034 329,96 (95 % CI [CHF 8 625 406,02; CHF 16 409 276,30]; 11 095 652,20 [7 952 624,35 ; 15 129 352,70 ]) per year was calculated for a population of 559 900 dairy cows. The main part of the losses is caused by an extended calving to conception interval: Seropositive animals need an average of 14,93 days longer (95 % CI [1,73; 28,13]) from calving to successful insemination as seronegative animals. This results in total costs for the extended calving to conception interval due to paratuberculosis of CHF 7 365 591,21 per year (95 % CI [CHF 900 394,95; CHF 14 838 087,61]; 6 791 075,10 [830 164,14 ; 13 680 716,80 ]). Milk yield reduction based on a lactation period of 305 days results in an economic loss of CHF 4 668 738,75 per year (95 % CI [CHF 1 571 188,69; CHF 7 725 011,07]; 4 304 577,13 [1 448 635,97 ; 7 122 460,21 ]). Milk fat and milk protein content were not found to be significantly changed. Despite a large number of studies in the screening phase, it was not possible to calculate all types of losses attributable to paratuberculosis due to lack of comparability between the studies, which is essential for meta-analyses. Nevertheless, it was possible to carry out four different meta-analyses, the results of which give a first impression of the economic importance of paratuberculosis in dairy cows in Switzerland.
INTRODUCTION: La paratuberculose des ruminants cause, particulièrement dans les régions ayant une industrie laitière intensive, des pertes économiques considérables, par exemple par la perte d'animaux malades, la réduction de la production laitière et une reproduction diminuée. Malgré la complexité de la quantification des pertes économiques effectives, on a essayé dans l'étude présentée ici de calculer les pertes causées par la paratuberculose dans les exploitations laitières en Suisse au moyen de méta-analyses. Dans ce but, des données extraites par un processus de sélection compliqué de 12 études sur la production laitière et de trois études sur la période de tarissement ont été utilisées pour calculer les pertes dues à la paratuberculose. De plus, huit études chacune sur la concentration de graisse et des protéines du lait ont été prises en compte. Seules des études où les animaux étaient classifiés comme «sains¼ (séronégatifs) et «malades¼ (séropositifs) sur la base d'un test ELISA sérique ont été prises en considération pour les méta-analyses. Pour une prévalence de la paratuberculose de 5,99 % chez les bovins en Suisse, on a pu calculer pour une population de 559 900 vaches laitières une perte totale de 12 034 329,96 CHF (IC 95 % [8 625 406,02 CHF; 16 409 276,30 CHF]; 11 095 652,20 [7 952 624,35 ; 15 129 352,70 ]) par année. La plus grande partie de ces pertes sont dues à une période de tarissement prolongée: les vaches séropositifs ont besoin en moyenne de 14,93 jours de plus (IC 95 % [1,73; 28,13]) du vêlage à une insémination menant à une gestation que les animaux séronégatifs. Il en résulte des coûts dus à la paratuberculose en raison d'une période de tarissement prolongée de 7 365 591,21 CHF par année (IC 95 % [900 394,95 CHF; 14 838 087,61 CHF]; 6 791 075,10 [830 164,14 ; 13 680 716,80 ]). La diminution de la production laitière cause pour une durée de lactation de 305 jours une perte économique de 4 668 738,75 CHF par année (IC 95 % [1 571 188,69 CHF; 7 725 011,07 CHF]; 4 304 577,13 [1 448 635,97 ; 7 122 460,21 ]). Les pertes en valeurs de graisse et de protéines du lait n'étaient pas significatives. Malgré le nombre élevé d'études prises en compte dans la phase de recherche de publications pertinentes, il n'a pas été possible de calculer tous les types de pertes, car les études n'étaient pas suffisamment comparables entre elles, ce qui est une condition essentielle pour une méta-analyse. Il a cependant été possible de procéder à quatre méta-analyses différentes, dont les résultats donnent une idée de l'importance économique des pertes liées à la paratuberculose chez les vaches laitières en Suisse.
Subject(s)
Cattle Diseases , Mycobacterium avium subsp. paratuberculosis , Paratuberculosis , Animals , Cattle , Cattle Diseases/epidemiology , Female , Lactation , Reproduction , Switzerland/epidemiologyABSTRACT
This study was conducted to evaluate the relationship between on-farm welfare, milk production, and reproductive performance in dairy herds in northwestern Spain. Data on the welfare status from 31 herds were collected using the Welfare Quality® protocol. Linear regression was applied to assess associations between WQ criteria/principle scores on farm average 305-d milk production and calving to conception interval (CCI). Results indicated that milk production was associated with the absence of prolonged hunger criterion (average increase of 22.33kg per unit score). Each one unit increase in the score for good feeding was also associated with a26.49kg increase in milk production. A10 unit increase in the scores for the absence of pain (by management procedures), expression of social behaviors, and absence of injuries was associated with reductions in CCI by 1.77, 0.8, and 0.29 days. CCI also decreased by 1.08 and 0.53 days when the principles of good health and appropriate behavior increased by 10 units. This study points out associations which can help encourage the dairy cattle sector to adopt practices that promote animal welfare.
Subject(s)
Animal Husbandry/methods , Animal Welfare/statistics & numerical data , Cattle/physiology , Dairying/methods , Animals , Behavior, Animal , Cattle/injuries , Diet/veterinary , Female , Lactation/physiology , Pain/veterinary , Reproduction/physiology , Social Behavior , SpainABSTRACT
AIM: This study analyzed risk factors influencing the conception rate at the first artificial insemination (CR1) in dairy cows reared in the plain of Mitidja, which is considered a major dairy region in North Algeria. MATERIALS AND METHODS: A total of 1054 lactations were used in the relational study of fertility conducted using the multivariable logistic regression model using the odds ratio (OR). RESULTS: The breeding season had a specific effect on fertility; the first service was often followed by pregnancy when performed during autumn (AUT) (OR=1.67, p<0.05) and spring (SPR) (OR=1.65, p<0.05). The chances of obtaining conception during the first service increased significantly for a waiting period (WP) (interval between calving and time to first service) of 50-100 days postpartum (DPP) (OR=1.67, p<0.05). CONCLUSION: From this study, it can be concluded that no specific effect was observed relative to the breed and parity. Furthermore, CR1 significantly increased after summer calving when the first services were performed during SPR and AUT and a WP after 50 DPP.
ABSTRACT
Prolonged calving-to-conception interval (CCI) can increase economic loss in cattle. We investigated the effect of post-calving abnormal reproductive tract discharge (ARTD) on CCI in dairy cows and quantified the relationship of ARTD and associated risk factors with CCI. The source population was dairy cows that calved in the study period on three pasture-based, year-round calving farms in the Riverina, NSW, Australia. Farm records and records from veterinarians' visits were analyzed. ARTD was defined as the presence of reproductive tract discharge according to the following classification: per vaginum purulent discharge ≥21 days post-calving or mucopurulent discharge >26 days post-calving. The incidence of ARTD was calculated. A Kaplan-Meier survivor function was used to estimate median time to conception post-calving dependent on the presence or absence of ARTD. Mixed effects Cox-proportional hazard models were used to estimate the direct and indirect effects of ARTD, and other potential risk factors on CCI such as body condition score (BCS), ambient temperature, and milk yield. Model structures were guided by a directed acyclic graph of potential risk factors for ARTD. The incidence of ARTD in lactations was 16% (95% CI 13.8-18.5%) and did not differ significantly between the three farms (P > 0.05). The median CCI was 176 and 118 days for lactations with and without ARTD, respectively (P < 0.01). The rate of pregnancy following calving in cows with ARTD was significantly decreased relative to the rate of pregnancy in cows without (total effect hazard ratio = 0.62, se = 0.18, P = 0.01). High peak milk yield (>32 L) and parity >2 also significantly extended CCI. We did not observe an effect of BCS or ambient temperature on CCI. The incidence of ARTD in the current study was consistent with clinical endometritis (considered a major source of ARTD) reported in other studies. In contrast-and despite regular veterinary assessment and treatment of on the farms in this study-ARTD extended CCI. Evaluation of the economic impact of ARTD on dairy farms in this region is warranted, and methods to identify high risk cows and develop effective interventions are required.
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The objective of this study was to evaluate the effect of subclinical mastitis (SCM) on calving-to-first-service interval (CFS), calving-to-conception interval (CC), and on the number of services per conception (S/C) in grazing Holstein and Normande cows. Primiparous (n=43) and multiparous (n=165) cows were selected from five dairy herds. Two composite milk samples were aseptically collected from each cow at drying-off, and then every week during the first postpartum month. One sample was used for somatic cell count (SCC), and the other one for bacteriological analysis. Cows were followed up to 300 d after calving. Non-parametric and parametric survival models, and negative binomial regression were used to assess the association between SCM, evaluated by SCC and milk culture, and reproductive indices. Staphylococcus aureus, CNS, and Streptococcus uberis were the most frequent isolated pathogens. Subclinical mastitis in the first month of lactation was not associated with CFS; however, the CC interval was longer in cows with SCM compared to healthy cows, the former also had a higher number of S/C.
Subject(s)
Animal Husbandry , Mastitis, Bovine/etiology , Animals , Bacterial Infections/veterinary , Cattle , Female , Milk/microbiology , Postpartum Period , Pregnancy , Reproduction , Risk FactorsABSTRACT
OBJECTIVE: To examine the impact of different degrees of lameness on the fertility of dairy cows. MATERIAL AND METHODS: Seven dairy herds housed in free stall barns with cubicles were visited at 4-week intervals and all cows were examined for locomotion characteristics using a locomotion scoring system. The cows received scores from 1 (normal gait) to 5 (severely lame). During the study period of 18 months, 893 cows in the first month of lactation and 944 cows in the second, third and fourth months of lactation were evaluated. Reproductive measures between non-lame cows (score 1), mild lame cows (score 2) and cows with clear lameness (score ≥ 3) were compared. RESULTS: Independent of parity and herd effects, cows with scores ≥ 3 in the first month of lactation displayed a 6 days longer calving to first service interval (CFSI) (86.2 ± 35.6 vs. 80.2 ± 34.1 days; p = 0.002) and a 16 days longer calving to conception interval (CCI) (119.7 ± 51.4 vs. 103.8 ± 55.5 days; p = 0.048) than non-lame cows. Additionally, the risk for non-conception was significantly higher in cows suffering from lameness in the first month of lactation (odds ratio: 2.1, 95% confidence interval: 1.095, 4.040; p = 0.026). Cows affected by mild lameness in the third month of lactation had a 4 days longer CFSI (84.7 ± 35.6 vs. 80.1 ± 30.5 days; p = 0.026) and a 18 days longer CCI (120.1 ± 55.4 vs. 102.3 ± 47.6 days; p = 0.016) than non-lame cows, while the CSFI in distinct lame cows was extended by 7 days compared to non-lame cows (87.2 ± 34.9 vs. 80.1 ± 30.5 days; p = 0.002). Cows with the score 1 in the first month and score 3 in the third month of lactation showed the longest CSFI (94.3 ± 33.9 vs. 76.5 ± 16.0 days in non-lame cows; p = 0.046). CONCLUSION AND CLINICAL RELEVANCE: This study suggests that both distinct and mild lameness in early lactation lead to a decline in reproduction in dairy herds. A regular determination of the lameness prevalence in dairy herds and optimizing claw health management, including early treatment of lame cows, will enhance animal welfare and reproduction efficiency.