Effect of alternative models for increasing stocking density on the short-term behavior and hygiene of Holstein dairy cows.

The primary objective of this study was to evaluate short-term responses in lying behavior and hygiene of Holstein dairy cows housed at a stocking density of 100 (1 cow per stall and headlock) or 142% imposed by 1) the denial of access to freestalls and headlocks, 2) the denial of access to freestalls, headlocks, and 26.6 m(2) of alley space, or 3) the addition of a rotating group of 14 cows to the resident group of 34 cows. The secondary objective was to determine the bioequivalence of the 3 methods of experimentally increasing stocking density. Cows (n=136) were assigned to 1 of 4 pens in a 4-row freestall barn and treatments were allocated using a 4×4 Latin square with 14-d periods. Lying time (h/d) and number of bouts/d for 12 focal cows per pen were determined using dataloggers recording at 1-min intervals during the final 5 d of each period. Dry matter intake (DMI) was established from the pen mean over the final 4 d of each period. Feeding and rumination activities on focal cows were determined by direct observation at 10-min intervals for 24h on d 11. Hygiene of focal cows was assessed from the difference in the scores after the legs and udder were cleaned on d 2 of each period and those on d 14. Lying time was greater for 100% stocking density (13.0 h/d) than the 142% stocking density treatments (11.8 h/d), which did not differ. Lying bouts (12.3/d) and bout duration (64.8 min/bout) did not differ among treatments. Short-term responses in DMI (24.6 kg/d) did not differ in response to the treatments. The 3 stocking density treatments decreased, or tended to decrease, the time spent feeding compared with 100% (4.4 versus 4.2 h/d). The stocking density treatments decreased the percentage of rumination occurring within a stall (92.3 versus 85.3%). A treatment effect on udder and leg hygiene scores was not evident on d 14 of each period or in the change from d 2 to 14 of each period. With the exception of rumination time (h/d), the 3 methods for experimentally imposing stocking density were bioequivalent for responses in behaviors, DMI, and hygiene. Future stocking density experiments in 4-row barns should simply deny resting and feeding space to simulate overcrowded housing conditions for lactating dairy cows because it is bioequivalent to more complicated, and potentially confounding, research models.

Effect of partial replacement of forage neutral detergent fiber with by-product neutral detergent fiber in close-up diets on periparturient performance of dairy cows.

The objective of this study was to determine the effect of partial replacement of forage neutral detergent fiber (NDF) with by-product NDF in close-up diets of dairy cattle on periparturient metabolism and performance. Holstein cows (n = 45) and heifers (n = 19) were fed corn silage-based diets containing 1) 30% oat hay, or 2) 15% oat hay and 15% beet pulp from d -21 relative to expected parturition until parturition. After parturition, all animals received the same lactation diet. Animals were group-fed from d -21 to -10 relative to expected parturition and fed individually from d -10 until 14 d in milk. Animals were required to have at least 5 d of prepartum dry matter intake (DMI) data to remain on the study. Data were analyzed as a randomized design and subjected to ANOVA using the MIXED procedure of SAS. Close-up diet did not affect DMI, total tract nutrient digestibility, energy balance, or serum content of nonesterified fatty acids and beta-hydroxybutyrate during the last 5 d prepartum. Prepartum body weight and body condition score were similar between treatments. There was no carryover effect of close-up diet on DMI, energy balance, milk yield, body weight, body condition score, or serum content of nonesterified fatty acids and beta-hydroxybutyrate during the first 14 d in milk. In summary, partial replacement of forage NDF (oat hay) with by-product NDF (beet pulp) did not affect periparturient metabolism or performance.

Comparison of corn silage hybrids for yield, nutrient composition, in vitro digestibility, and milk yield by dairy cows.

A study was undertaken to compare Novartis N29-F1, a dual-purpose 90-d relative maturity corn hybrid, and Novartis NX3018, a 90-d relative maturity leafy corn silage hybrid for dry matter (DM) yield, in vitro digestibility, plant components, nutrient composition, and lactational performance by Holstein cows. The two corn hybrids were planted in replicated 15.2- x 321-m plots. Plant population and DM yield were similar between the two corn hybrids. Novartis NX3018 had higher content of crude protein and ash, a higher proportion of leaves and stalks, and a lower proportion of grain compared with Novartis N29-F1. The cob, grain, and leaves of Novartis NX3018 had higher in vitro true DM and neutral detergent fiber disappearances compared with the respective plant components of Novartis N29-F1. Thirty-eight midlactation multiparous Holstein cows (78 +/- 23.0 days in milk) producing 47.2 +/- 8.9 kg of milk per cow per day were blocked and assigned randomly to one of two total mixed ration (TMR) containing (DM basis) approximately 26% Novartis N29-F1 or Novartis NX3018 corn silage. Cows were housed in a free-stall barn and group fed ad libitum. The lactation study was conducted as a crossover design with two 28-d periods. Samples and data were collected during the final 7 d of each period. The total mixed rations were formulated using the Cornell-Penn-Miner Dairy nutrition model. Cows that were fed the total mixed rations containing Novartis NX3018 corn silage produced higher yields of milk 3.5% fat-corrected milk (FCM), milk crude protein, and milk lactose compared to cows that were fed the TMR containing Novartis N29-F1 corn silage. In conclusion, the Novartis NX3018 corn hybrid was leafier and more digestible in vitro, and when fed to dairy cows as silage, promoted higher milk yield compared with the Novartis N29-F1 corn hybrid.

Effect of corn silage hybrid on dry matter yield, nutrient composition, in vitro digestion, intake by dairy heifers, and milk production by dairy cows.

Three corn hybrids, Mycogen TMF94, Cargill F337 (which contains a brown midrib trait), and Pioneer 3861 were compared in a plot trial, an intake trial, and a lactation trial. In the plot trial, the three corn hybrids were planted in replicated 15.2 x 385-m plots. Mycogen TMF94 and Cargill F337 had lower yields of dry matter (DM), higher concentrations of neutral detergent fiber, and higher in vitro true DM disappearance compared with Pioneer 3861. Mycogen TMF94 had a higher yield of DM than Cargill F337 despite having a lower plant population. However, Cargill F337 had a higher in vitro true DM disappearance than Mycogen TMF94. In the intake trial, six individually penned Holstein heifers were blocked and assigned randomly to one of three total mixed rations containing 79% (DM basis) Mycogen TMF94, Cargill F337, or Pioneer 3861 corn silages in replicated 3 x 3 Latin squares. Heifers fed the Pioneer 3861-based TMR had lower DMI than heifers fed Mycogen TMF94 and Cargill F337-based TMR. In the lactation trial, 75 midlactation Holstein cows were blocked and assigned randomly to one of three total mixed rations containing 31% (DM basis) Mycogen TMF94, Cargill F337, or Pioneer 3861 corn silages used in the intake trial. Milk production was highest for cows fed Cargill F337-based total mixed rations. It is concluded from this study that Mycogen TMF94 was higher yielding, but less digestible, and resulted in lower milk production by lactating cows than Cargill F337. In addition, Mycogen TMF94 had higher in vitro true DM disappearance, and similar DM yield and milk production by lactating cows when compared with Pioneer 3861.

Effect of variation in proportion of cornmeal and steam-rolled corn in diets for dairy cows on behavior, digestion, and yield and composition of milk.

Sixty-six lactating multiparous Holstein cows (113+/-46 DIM) housed in a free-stall facility were blocked and assigned randomly to one of three treatments to evaluate the effects on animal performance from feeding cornmeal, cornmeal mixed with steam-rolled corn in a ratio of 1:1 on dry matter basis, or steam-rolled corn. The only difference in the dietary ingredients was the type of corn, which was included in the total mixed ration (TMR) at 17% of dry matter. The densities (g/L) of cornmeal and steam-rolled corn were, respectively, 635 and 553. Diets were fed as TMR and were formulated according to the Cornell Penn Miner Dairy nutrition model. The TMR consisted of 40% forage and 60% concentrate on dry matter basis. The first 2 wk of the 8-wk study was a preliminary period, and data collected during this period were used as covariate in statistical analysis of production data collected during wk 6 to 8. Treatment diets were fed from wk 3 to 8. Total tract digestibilities of dry matter, organic matter, crude protein, starch, and neutral detergent fiber were not significantly different among treatments. Cows fed TMR containing steam-rolled corn had higher body condition and ruminated longer. However, feeding cornmeal and steam-rolled corn together did not improve dry matter and nutrient digestion, milk yield, 3.5% fat-corrected milk yield, and percentage and yield of fat, crude protein, true protein, and lactose in milk, and milk urea nitrogen. In conclusion, feeding steam-rolled corn improved animal body condition and rumination. Partial or complete substitution of cornmeal by steam-rolled corn in diets for lactating dairy cows did not improve dry matter and nutrient digestion, milk yield, and milk composition.

Flight nurse interpretations of chest radiographs.

The authors conducted a study to determine whether basic instruction in reading chest radiographs could enable flight nurses to interpret radiographs accurately. Flight nurses were taught 10 trauma-related chest roentgenographic patterns. The chest radiographs of 40 transported trauma patients were chosen randomly over a 14-month period for interpretation by a flight nurse and a referring physician. Flight nurses correctly identified 47 out of 55 patterns (85%). Referring physicians correctly identified 37 out of 55 (67%). Flight nurses also correctly identified 13 patterns that the referring physicians missed. The results indicate that emergency radiologists can advance and improve the radiological aspects of emergent patient care by providing flight nurses with minimal training in interpreting radiographs. When a flight nurse and a physician in an outlying area--where trauma is less commonly encountered--work as a team, more accurate and earlier diagnoses can be made, and therapy can be instituted earlier.

Spontaneous internal carotid artery dissection shown by magnetic resonance imaging.

We have reported a case of spontaneous dissection of the internal carotid artery, with MRI and angiographic findings. We conclude that MRI is a beneficial noninvasive test for the detection and study of carotid artery dissection.

Traumatic esophageal rupture: unusual cause of acute mediastinal widening.

We have presented the case of a 32-year-old man who sustained blunt trauma to the chest in a motor vehicle accident. Plain roentgenograms showed a widened mediastinum and pneumomediastinum, and an esophagogram with water-soluble contrast material showed an esophageal laceration at the T-4 level.

Herpes encephalitis: MR monitoring of response to acyclovir therapy.

Viral encephalitis secondary to herpes simplex virus type I is thought to be the single most important cause of fatal, sporadic encephalitis in the United States. Magnetic resonance not only improves early diagnosis of herpes encephalitis but also is effective in documenting response to antiviral therapy.

Colon carcinoma metastatic to the thyroid gland.

Metastatic carcinoma to the thyroid gland rarely is encountered in clinical practice; however, autopsy series have shown that it is not a rare occurrence. A case of adenocarcinoma of the colon with metastases to the thyroid is reported. A review of the literature reveals that melanoma, breast, renal, and lung carcinomas are the most frequent tumors to metastasize to the thyroid. Metastatic disease must be considered in the differential diagnosis of cold nodules on radionuclide thyroid scans, particularly in patients with a known primary.