What a terrible loss and yes, a reminder for all of us to keep our livestock away from frozen ponds!
Last winter I had one of my mares fall through the ice on my not very deep pond. Due to the ice and mud, she couldn't get out. Fortunately, I found her still struggling. There was no way I could get her out even with a rope around her neck. I knew it would be foolish of me to try to go in the water to try to save her as it was only 15 F outside and we didn't need 2 drownings. I ran back to the barn and called 911. I got the fire dept and they were here within 10 - 15 min of my call. 6 firefighters with some heavy rope got in the pond and looped it under her belly, then they pulled her right out. We took her to the barn and with lots of towels and a hair dryer, finally got her to quit shivering. I left her blanketed and heat lamps on. Thankfully, she is fine today thanks to the quick response of the firefighters!