You are quite right heat stress can affect animal productivity significantly. In the temperate zone this is something that is often ignored yet we know very well that in summer ambient temperatures are often above the thermo neutral range.
It is notable you advise feeding of fats. This is fine as long as the fat supplement does not depress dry matter intake which is critical during heat stress. Calcium salts of fatty acids can decrease dry matter intake by 2.5% for each percentage unit in the diet according to NRC (2001).
In hot climates such as in Middle East forages fed are often inadequate and of poor quality. This affects rumen environment and overall fibre digestibility. On the other hand replacing fibrous feeds with readily fermentable carbohydrates could further upset rumen function by lowering pH.
The ideal solution is a supplement that combines energy supply and rumen buffering properties.
Betaine has demonstrated significant effects in helping to mitigate the effects of heat stress on dairy and beef cattle, resulting in lower body temperatures, reduced respiration, increased feed intake, higher milk production, etc.