The effect of temperate or tropical pasture grazing state and grain-based concentrate allocation on dairy cattle production and behavior.

Grain-based concentrate (GBC) supplement is of high cost to dairy farmers as a feed source as opposed to grazed pasture. Milk production response to GBC is affected by the composition and nutritive value of the remainder of the diet, animal factors, and interactions between forage type and level of GBC. In grazing systems, dairy cattle encounter contrasting pasture states, primarily because the social structure of the herd affects the timing of when each animal accesses a paddock after milking as a result of a relatively consistent cow milking order.

Grazing Soybean to Increase Voluntary Cow Traffic in a Pasture-based Automatic Milking System.

Pasture-based automatic milking systems (AMS) require cow traffic to enable cows to be milked. The interval between milkings can be manipulated by strategically allocating pasture. The current experiment investigated the effect of replacing an allocation of grazed pasture with grazed soybean (Glycine max) with the hypothesis that incorporating soybean would increase voluntary cow traffic and milk production.

Acute phase proteins in cattle: discrimination between acute and chronic inflammation.

Acute phase proteins such as serum amyloid A, haptoglobin, and alpha 1-acid glycoprotein have been identified as markers of inflammation in cattle because they are produced by the liver in response to pro-inflammatory cytokines. This study was designed to assess whether they could be used to discriminate between acute and chronic inflammation. Their concentrations were measured in serum samples from 81 cattle in which inflammation was classified by thorough clinical examination, supported by postmortem findings, as being acute in severity in 31 and chronic in 50.

First evidence for the existence of multiple isoforms of bovine serum amyloid-A (apoSAA).

Bovine serum amyloid-A (SAA) was purified from acute-phase high density lipoprotein (HDL) by affinity chromatography and subsequent gel filtration chromatography. The identity of the isolated protein was checked by Western blotting following SDS-urea-PAGE using antisera raised against the purified protein fraction (SAA) and Amyloid A (AA). The antiserum raised against the purified SAA stained Congo red positive regions in the kidney of an AA-amyloidotic cow and reacted on Western blot with an AA-related protein of approximately 14 kDa.

Immediate responses in serum TNF alpha and acute phase protein concentrations to infection with Pasteurella haemolytica A1 in calves.

The concentrations of tumour necrosis factor-alpha (TNF alpha), serum amyloid A (SAA) and haptoglobin were determined in serum samples taken from four calves in the 10 hours after their intra-tracheal inoculation with Pasteurella haemolytica serotype A1. The concentration of haptoglobin did not increase but the concentration of SAA rose progressively from within two hours of inoculation. The concentration of TNF alpha reached a peak in all the animals two hours after inoculation but had returned to undetectable levels after a further four hours.