Use of residual feed intake in Holsteins during early lactation shows potential to improve feed efficiency through genetic selection.

Improved feed efficiency is a primary goal in dairy production to reduce feed costs and negative impacts of production on the environment. Estimates for efficiency of feed conversion to milk production based on residual feed intake (RFI) in dairy cattle are limited, primarily due to a lack of individual feed intake measurements for lactating cows. Feed intake was measured in Holstein cows during the first 90 d of lactation to estimate the heritability and repeatability of RFI, minimum test duration for evaluating RFI in early lactation, and its association with other production traits. Data were obtained from 453 lactations (214 heifers and 239 multiparous cows) from 292 individual cows from September 2007 to December 2011. Cows were housed in a free-stall barn and monitored for individual daily feed consumption using the GrowSafe 4000 System (GrowSafe Systems, Ltd., Airdrie, AB, Canada). Animals were fed a total mixed ration 3 times daily, milked twice daily, and weighed every 10 to 14 d. Milk yield was measured at each milking. Feed DM percentage was measured daily, and nutrient composition was analyzed from a weekly composite. Milk composition was analyzed weekly, alternating between morning and evening milking periods. Estimates of RFI were determined as the difference between actual energy intake and predicted intake based on a linear model with fixed effects of parity (1, 2, ≥ 3) and regressions on metabolic BW, ADG, and energy-corrected milk yield. Heritability was estimated to be moderate (0.36 ± 0.06), and repeatability was estimated at 0.56 across lactations. A test period through 53 d in milk (DIM) explained 81% of the variation provided by a test through 90 DIM. Multiple regression analysis indicated that high efficiency was associated with less time feeding per day and slower feeding rate, which may contribute to differences in RFI among cows. The heritability and repeatability of RFI suggest an opportunity to improve feed efficiency through genetic selection, which could reduce feed costs, manure output, and greenhouse gas emissions associated with dairy production.

Revision arthroscopic capsulolabral reconstruction for recurrent instability of the shoulder.

We have investigated the outcome of arthroscopic revision surgery for recurrent instability of the shoulder after failed primary anterior stabilisation. We identified 40 patients with failed primary open or arthroscopic anterior stabilisation of the shoulder who had been treated by revision arthroscopic capsulolabral reconstruction and followed up for a mean of 36 months (12 to 87). There were 34 men and six women with a mean age of 33.1 years (15 to 48). Details of the patients, the technique of the primary procedure, the operative findings at revision and the clinical outcome were evaluated by reviewing the medical records, physical examination and the use of the Western Ontario shoulder instability index score, the American Shoulder and Elbow Surgeons score and the health status questionnaire 12. Recurrent instability persisted in four patients after the revision arthroscopic procedure. At the final follow-up, the mean American Shoulder and Elbow Surgeons score was 81.1 (17.5 to 99.5) and the mean Western Ontario shoulder instability index score was 68.2 (20 to 98.2). Quality-of-life scoring showed good to excellent results in most patients. Arthroscopic revision capsulolabral reconstruction can provide a satisfactory outcome in selected patients for recurrent instability of the shoulder provided that no large Hill-Sachs lesion is present.

Ankle fractures in diabetics. Complications of surgical management.

To determine the relative risk of complications in treating ankle fractures in patients with diabetes, we compared the results of the management of displaced malleolar fractures in 26 patients with those of a matched group of non-diabetic patients, using a case-controlled study. The groups were matched for patient age, fracture type and treating surgeon. The incidence of significant complications in diabetic patients was 42.3%. By contrast, there were no complications in the matched group of non-diabetic patients. Of 19 diabetic patients treated surgically, six developed major complications including one case of malunion, one of necrosis of the wound edge requiring a flap, and two of deep sepsis. Two patients required amputation and both died. Diabetic patients with displaced ankle fractures treated non-operatively had a high incidence of loss of reduction and malunion but these caused few symptoms. In these patients, non-operative management may be preferable in view of the high risks of major complications after surgery and the acceptance of malunion by the older patient with lower demands.

Valgus stress radiography in normal ankles.

Deltoid ligament injury is thought to be rare. Signs of complete rupture of the deltoid ligament may be subtle or interpreted as another injury condition and thus are often missed acutely. No standardized method has been created to evaluate medial ligament insufficiency in acute or chronic laxity. To establish a diagnostic test for suspected isolated ruptures of the deltoid ligament, 32 subjects with no previous ankle injury underwent valgus stress radiography and nonstressed radiography of both ankles. Stress radiography in this study showed that there is a measurable but minimal range of talar tilt on valgus stress in previously uninjured ankles. This study provides the basis for diagnosis of the rare isolated rupture of the deltoid ligament of the ankle.