# Impact of chronic cold stress on metabolism, colostrum quality, and lamb performance in locally adapted ewes

## TL;DR

This study found that Morkaraman sheep produce healthier lambs under cold stress, but their colostrum quality declines faster than Awassi sheep.

## Contribution

The study reveals breed-specific physiological responses to chronic cold stress in sheep, linking metabolism, colostrum quality, and lamb performance.

## Key findings

- Morkaraman lambs had higher birth weights and growth rates under cold stress compared to Awassi lambs.
- Cold stress altered serum biochemistry, with Morkaraman ewes showing higher triglyceride and GGT levels.
- Colostrum quality declined over time, with faster decreases in immunoglobulin G and GGT in Morkaraman ewes.

## Abstract

This study evaluated the effects of chronic cold stress on metabolism, colostrum quality, and early lamb performance in two environmentally resilient sheep breeds: Morkaraman and Awassi. The study included 20 ewes (10 each breed) and their lambs (10 per breed). This study evaluated serum biochemical parameters and colostrum quality and composition in sheep and assessed the growth performance of lambs during the first seven days of life under cold environmental conditions. Findings indicated that Morkaraman lambs exhibited higher birth weights and superior growth rates compared to Awassi lambs under cold conditions. Cold stress significantly influenced serum biochemical parameters, with Morkaraman ewes showing higher triglyceride and gamma-glutamyl transferase (GGT) levels. Colostrum quality declined over time in both breeds; however, immunoglobulin G and GGT concentrations decreased more rapidly in Morkaraman ewes. In conclusion, Morkaraman sheep demonstrated better lamb growth performance under chronic cold stress, but this advantage was accompanied by a faster deterioration in colostrum quality, indicating breed-specific physiological responses to cold environments.