An investigation into the development of right displaced abomasum by rolling 268 dairy cows with left displaced abomasum.

Right displaced abomasum (RDA) and abomasal volvulus (AV) are common diseases in cattle. However, presently there is no consensus regarding the pathogenesis and nomenclature of the different positions that the abomasum can adopt in the right side of the cow. Therefore, the objective of this study was to describe the etiopathogenesis of the right displaced abomasum according to the description of the features observed in 268 cows with left displaced abomasum (LDA), which were rolled to induce the movement of the abomasum from the left side to the right (in fact, inducing an RDA in 44% of cases), to facilitate the surgical approach, and immediately surgically treated (abomasal omentopexy from the right side). The observed RDA positions matched previously published descriptions and names, and the authors propose a holistic and simpler nomenclature and a clear hypothesis on RDA etiopathogenesis. In 54.1% of the cases, the abomasum moved to a normal position after rolling. The most common RDA position observed was caudal displacement of the RDA (CdRDA; 70 out of 119 RDA cases; 26.1% of the total number of cows), followed by lateral displacement (LRDA; 32 of 119; 11.9% of all cases), cranial displacement (CrRDA; 8 of 119; 3% of the total), medial displacement (MRDA; 4 of 119; 1.5% of the total), and finally, displacement lateral to the omasum (LORDA; 3 of 119; 1.1% of the total). Adverse events directly due to the rolling procedure were mesenteric root volvulus (3 of 268), cecocolic volvulus (2 of 268) and torsion (1 of 268), and uterus torsion (2 of 10 pregnant cows); 1 abortion (1 of 10 pregnant cows) was also observed. We suggest that CdRDA is the first stage of an RDA that can become an LRDA with increasing pressure. An LRDA can become an AV if rotating counterclockwise, viewed from above. An LDA, CdRDA, or LRDA could be initial forms of LORDA and CrRDA, and occur when forestomachs are empty or when the animal stands up on its front legs first. The LORDA and CrRDA forms can lead to an omasum-abomasum volvulus (OAV) or to a reticulum-omasum-abomasum volvulus (ROAV) when pressure increases. With this study we establish, for the first time, the sequence and incidence of each RDA form and its complications, increasing knowledge of this syndrome and its pathogenesis. This understanding critically aids the surgeon's ability to accurately assess and correct this disease and to predict prognosis.

Efficiency and demographics of a high-yield dairy ewe farm with two managing systems involving five or 10 lambings per year.

This study assessed milk productivity, demographic characteristics and workload distribution on a single high-yield dairy ewe farm in Spain (Avila, Spain; continental climate, latitude of 40.90 N, altitude of 900 m) over a 7-year period considering a transition from a herd management system involving five lambings per year (5LY) to a system involving 10 lambings per year (10LY). The 5LY system was practiced on the farm from 2010 to 2012 and the 10LY system from 2014 to 2015, with 2009 and 2013 being considered transition years. During this period, 27 415 lactations were recorded from an average of 3746 Lacaune sheep/year. Several productivity parameters were higher in 2014 to 2015 than in 2010 to 2012: milk yield/lactation (370±156 v. 349±185 l), lactation length (218±75 v. 192±75 days) and dry period length (53.5±38.3 v. 69.1±34.8 days) (all P<0.0001). During 2014 to 2015, investment in new lambing facilities was possible, workload was distributed more uniformly throughout the year, workload per worker was smaller, rate of ewe culling was lower (35.39±0.53% v. 42.51±7.51%), ewe longevity was greater and higher-order lactations were more numerous (P<0.0001). On the other hand, during 2010 to 2012, daily production was higher (1.73±1.66 v. 1.70±0.62 l/day; P=0.038), the interlambing period was shorter (283±50 v. 302±44 days; P<0.0001) and lambings/ewe per year were greater (1.42±0.01 v. 1.30±0.01; P<0.05). These results suggest that a 10LY herd management system can be compatible with profitability, productivity and good animal and worker's welfare on a high-yield dairy farm, and may even be associated with better outcomes than a 5LY system.

Treatment of naturally occurring bovine respiratory disease in juvenile calves with a single administration of a florfenicol plus flunixin meglumine formulation.

The efficacy and safety of a florfenicol plus flunixin meglumine formulation in the treatment of respiratory disease was evaluated in calves less than six weeks of age, compared with a positive control group treated with a well-established florfenicol formulation. A total of 210 calves, selected from nine sites in Belgium, France and Spain, showing severe signs of respiratory disease, were randomly assigned to treatment with either florfenicol plus flunixin meglumine (Resflor; MSD Animal Health) or florfenicol (Nuflor; MSD Animal Health), both administered subcutaneously once. Animals were clinically observed daily for 10 days following treatment initiation. The predominant respiratory pathogens were Pasteurella multocida, Mycoplasma bovis, Mannheimia haemolytica and Histophilus somni. All isolates were subject to in vitro sensitivity testing and found susceptible to florfenicol. In both groups, rectal temperature dropped and clinical index (depression and respiratory signs) significantly improved after treatment. Specifically, for the change in rectal temperature from pretreatment to six hours post-treatment, the florfenicol-flunixin formulation was found significantly superior to florfenicol. Moreover, the florfenicol-flunixin formulation alleviated the clinical signs of disease more rapidly, and was demonstrated to be non-inferior to florfenicol on days 4 and 10. The use of the product combining florfenicol and flunixin in calves is safe and efficacious in the treatment of outbreaks of bovine respiratory disease.

Accurate mathematical models to describe the lactation curve of Lacaune dairy sheep under intensive management.

Although the intensive production system of Lacaune dairy sheep is the only profitable method for producers outside of the French Roquefort area, little is known about this type of systems. This study evaluated yield records of 3677 Lacaune sheep under intensive management between 2005 and 2010 in order to describe the lactation curve of this breed and to investigate the suitability of different mathematical functions for modeling this curve. A total of 7873 complete lactations during a 40-week lactation period corresponding to 201 281 pieces of weekly yield data were used. First, five mathematical functions were evaluated on the basis of the residual mean square, determination coefficient, Durbin Watson and Runs Test values. The two better models were found to be Pollott Additive and fractional polynomial (FP). In the second part of the study, the milk yield, peak of milk yield, day of peak and persistency of the lactations were calculated with Pollot Additive and FP models and compared with the real data. The results indicate that both models gave an extremely accurate fit to Lacaune lactation curves in order to predict milk yields (P = 0.871), with the FP model being the best choice to provide a good fit to an extensive amount of real data and applicable on farm without specific statistical software. On the other hand, the interpretation of the parameters of the Pollott Additive function helps to understand the biology of the udder of the Lacaune sheep. The characteristics of the Lacaune lactation curve and milk yield are affected by lactation number and length. The lactation curves obtained in the present study allow the early identification of ewes with low milk yield potential, which will help to optimize farm profitability.

New surgical technique to correct urovagina improves the fertility of dairy cows.

Several surgical techniques have been proposed for the treatment of urovagina as a major cause of infertility in cows. However, so far no technique seems to be successful in all cases. Given that an incompetent or damaged constrictor vestibuli muscle is a feature of cows with urovagina, we hypothesized that surgical correction of urovagina by cerclage of the vestibulovaginal junction under the vaginal wall cranial to the urethral opening would prevent cranial flow of urine and improve fertility. Our study was performed on 39 non-pregnant lactating Holstein-Friesian cows suffering urovagina, with a vaginal content of urine exceeding 100mL and with evident incompetence of the constrictor vestibuli muscle. Cows were randomly assigned to a Control (untreated cows, n=20) or Experimental (n=19) group. An encircling polydioxanone suture was placed in the vaginal wall at the vestibulovaginal junction to create a vestibulovaginal cerclage in the Experimental cows. Surgery was observed to resolve urovagina in 17 (89.5%) of the 19 treated cows. Pregnancy was recorded in 7/20 (35%) and 14/19 (74%) cows in the Control and Experimental groups, respectively. Using logistic regression procedures and based on the odds ratio, we determined that cows undergoing surgical correction of urovagina were 5.2 times more likely to become pregnant than untreated cows (P=0.015). Our results suggest that vestibulovaginal junction cerclage prevents the cranial flow of urine and improves the function of the constrictor vestibuli muscle in cows suffering urovagina. They also indicate that, under these conditions, urovagina correction may dramatically increase fertility.