The RSPCA has confirmed that it is reviewing the role of its animal welfare officers amid concerns that almost 50 such roles could be lost or downgraded.
The animal charity said it was carrying out a review of the positions held by 46 animal welfare officers in order to make its services as effective and efficient as possible.
An RSPCA source said some staff found out about the review on social media, with others being informed by colleagues and others contacted directly by a manager.
The source said the officers could face redundancy or demotion to lower-paid roles.
"There have been tears and anger at this appalling decision," the source said. "Many of the staff affected have worked for the charity for years and feel very let down."
The charity did not comment directly on the claims when contacted by Third Sector.
Chris Wainwright, director of communications at the RSPCA, said: "We are reviewing the role of animal welfare officers as we seek to make our front-line services as effective and efficient as possible to help those animals most in need.
"This will enable us to better meet public expectations and the growing demand on our limited resources. No final decisions have been taken."
The charity has 1,600 staff, including 381 inspectors, 101 animal collection officers and the 46 animal welfare officers.