History and Characteristics of Ross Chicken
Aviagen, a Scottish company founded in 1920, underwent fundamental changes in 1962 and became the largest poultry producer in Europe. The Ross 1 breed entered the American market in 1987, and its modified version, Ross 708, was introduced in 2004.
Among the well-known breeds of this brand that spread in Iran in the 1970s (Persian calendar), we can mention the 208 and 308 breeds.
Reasons for the popularity of Ross chick among poultry farmers include the following characteristics:
- Ross chicken are white and heavier compared to other local chicken.
- Ross Brolier reach a weight of 2 to 3 kg in 45 days, while local broilerchicken reach this weight in 2 to 3 months.
- Ross chicken generally have a broad chest, wide legs, and a large appetite, which allows them to grow quickly.
- Ross broiler chickens are also popular among backyard chicken keepers.
Types of Ross Broiler Chickens
To date, Ross has not released precise information about the breeds used in the production of its strains. This is usually done for various reasons, including preserving trade secrets and preventing copying by competitors. By combining several broiler breeds, Aviagen has been able to produce chicken with different strains for greater meat production and faster growth.
Currently, the types of Ross Broiler breeds in the world include Ross 708, 308, and AP 308. All of the above have parent stock, maternal stock, and finally broiler chicken, which can be prepared depending on the production goal.

Ross 308 Broiler Chick: Characteristics and Features of the Ross 308 Broiler Breed
The Ross 308 broiler chick is one of the most popular broiler chicken in the world because it has consistent performance and high adaptability. Due to the integrated breeding of the Ross 308 chicken, it has a high growth rate, feed efficiency, and strong performance, which has made this chicken popular among producers. The Ross breed has a very excellent growth rate.
Physical Characteristics of the Ross 308 Chick
If you look at the Ross 308, it is almost similar to other broiler chicken breeds. The color of this chick’s feathers is white. Its tail is vertically shaped and also white in color. The Ross 308 has an active and upright body. This chick has an oval body, a small head with a large red comb, and a broad, protruding chest. The Ross 308 chicken matures in a period of 38 to 41 days.
Physical Characteristics of the Ross 308 Chicken at a Glance:
- White feather color
- White vertical tail
- Active and upright body
- Oval body
- Small head with a large red comb
- Broad, protruding chest
- Maturity in 38 to 41 days
Characteristics of the Ross 308 Chicken Breed
If health principles are observed, this strain has a high conversion ratio. Also, the percentage of leg problems in this breed is less than in the Cobb breed. The Ross broiler chick is the best choice for heavy weights (over 2.5 kg). The characteristics of the Ross 308 chicken breed can be mentioned as follows:
- High conversion ratio if health principles are observed
- Lower percentage of leg problems than the Cobb breed
- Best choice for heavy weights (over 2.5 kg)
- Excellent weight gain
- Low production cost with low carcass meat loss
- Large and strong legs
- Excellent feed conversion
- Large white breasts
- High survival rate (Remarkable figures for survival)
Due to the good growth and large volume of the breasts of the Ross 308 chicken, the chest of this breed is more towards the ground. If a suitable litter is not provided, it will be burned and its marketability will be reduced. Also, this breed is more involved in heat stress compared to the Cobb breed.
The Ross 308 Broiler catalog
You can get the latest catalog of each breed from the Aviagen website. For example, for the Ross 308 Broiler, whether as a meat chicken or a parent stock, click here.
Article: Understanding and Reviewing the Cobb Broiler Breed

Ross 708 Broiler: Characteristics and Features of the Ross 708 Broiler Breed
The Ross 708 chick is significantly heavier than the 308 model and has a higher conversion ratio. In fact, the Ross 708 maternal stock has been bred to maximize breeding performance without compromising meat production efficiency. This is because birds bred for meat production need to focus on improving key traits. Maintaining the efficiency of converting feed to more carcass meat.
This flow is important because the demand for boneless meat in the market has increased. The cost of consumed feed is the highest cost in poultry production. Therefore, a breed of chicken that can produce more meat by consuming less feed is more valuable.
Difference between Ross 308 and Ross 708: Comparison of Two Ross Strains
The main difference between Ross 308 and Ross 708 is faster weight gain. In just 35 days (with compliance with all breeding rules), the weight of birds increases by 3 kg. In one of the articles of the Journal of Applied Poultry Research, it is prepared that previous research has shown that broiler chickens of the Ross 308 strain performed better in the lower body cuts, namely the thigh, upper thigh, and drumsticks. But in Ross 708, more breast meat is produced.
Also, research in the Canadian Journal of Animal Science on the performance of two species of Ross 308 and Ross 708 chickens under the same breeding and feeding conditions, the difference between the two strains is expressed as follows:
Growth performance: Ross 308 is marketed due to its constant performance in poultry houses, while Ross 708 is bred for high meat production and superior feed conversion efficiency.
Chicken body fat: Researchers found that both breeds generally grow well, but Ross 708 chickens have less abdominal fat compared to Ross 308, and store more fat in their breast muscles. Also, the composition of fatty acids in the breast muscles of these two breeds was also different.
Response to Tributyrin: Tributyrin is a butyric acid glyceride that has been shown to have several positive effects on the performance of broiler chickens and can be a potential alternative to existing antibiotics in feed. In this research, researchers found that adding a substance called tributyrin to the feed of chickens has effects on fat metabolism in both breeds, but these effects were greater in Ross 708 chickens.
In summary, this study showed that even broiler chicken breeds that are very similar genetically can have significant differences at the metabolic level and respond differently to changes in the diet. This can be important for broiler producers to be able to choose the best breed according to their goals.

Ross 308 AP: A top-performing chick with exceptional feed conversion and growth rate.
The Ross 308 AP offers viable broiler chicken and processing performance with excellent feed conversion ratio and growth rate. This Ross chicken breed is very popular in the United States and Latin America and is referred to as “the complete package”. This breed has also been experimentally exploited in India.
Characteristics of the Ross 308 AP Chick:
The Canadian Poultry magazine writes about the Ross 308 AP breed as follows:
- High environmental tolerance for all types of climates
- Improved feed conversion rate two to three points lower (among Latin American customers)
- Improved growth rate
- Reduced production costs
Kevin McDaniel, president of Aviagen North America, said about the growing popularity of this bird:
“The performance benefits of Ross 308 AP broiler chicken have helped promote the business of Latin American poultry farmers, and these same benefits have led to the rapid growth of this species in US farms as well.“
The website “the poultry punch” also reports on the use of this breed in India as follows:
This broiler chick has significant growth throughout India. Some of the features of the Ross 308 AP can be mentioned as follows:
- Healthy growth
- Strong viability
- High meat yield
- Farm efficiency
Differences between Ross 308 and Ross 308 AP Broiler
Aviagen, the producer of Ross Broilers, has provided explanations regarding the key differences between the Ross 308 and Ross 308 AP (male and female parents) chiken. Ross 308 AP chiken have a larger skeletal size compared to Ross 308. This means their bone structure is larger and coarser. Due to this difference in size, the body weight of these two breeds is also different. Considering these differences, it is very important to carefully check and control the body weight and size of male and female chicken from both breeds (Ross 308 AP).
On the other hand, despite the similar breeding management of these two breeds, there are important points to consider:
- Growth Rate and Feed Consumption: The Ross 308 AP chick has a higher growth rate and feed consumption compared to the Ross 308. Therefore, managing flock uniformity in this breed is of particular importance. To ensure optimal growth, the goal is for the crop of more than 95% of the chicken to be full 24 hours after entering the hall.
- Body Weight and Skeletal Size of Males: Controlling the body weight and skeletal size of males in the Ross 308 AP breed is very important to achieve the best results in mating and fertility.
- Feed Conversion Ratio (FCR): One of the main advantages of the Ross 308 AP is its better feed conversion ratio compared to the Ross 308. This means that Ross 308 AP chicken gain more weight by consuming less food, which leads to lower production costs.
- 3-Stage Breeding Program: To achieve maximum growth and production potential, the Ross 308 AP should be subjected to a 3-stage breeding program.
- Proper Nutrition: Pay special attention to the nutrition of the females and avoid overfeeding them, especially during peak egg production.
- Conservative Feed Restriction: Feed restriction for the Ross 308 AP is done more carefully and conservatively.
- Egg Humidity Control: Carefully control the humidity of the Ross 308 AP eggs to improve hatchability.
Ross Laying Hens: Do We Also Have Ross 308 Laying Hens?
The question that may arise for some people is, do we also have Ross 308 laying hens? All Aviagen chickens under the Ross brand have been for broiler production. As you know, raising broilers is very different from raising laying hens.
On the other hand, parent and grandparent stock are also available in all Ross strains. The type of breeding, feeding, and breeding of these chickens is different from laying hens with the aim of producing eggs for the market. Sometimes, if parent stock chicken are stocked on a farm, the surplus chicken of the meat parent stock are sent to a broiler poultry farm for rearing. But experience has shown that these chickens, with the aim of raising broiler chickens in the market, did not have good weight gain and performance coefficient. For this reason, it is very important that when buying day-old chicken, be sure to prepare the broiler chicken according to the breeding goal.

The Best Broiler Feed for Ross Breed or Parent Stock
In the Ross Broiler Pocketbook, in the section on feed quality for Ross broilers, it is recommended to use pelleted or crumbled feed. In fact, they believe that the growth of broilers is the result of the nutrient content of the diet and feed consumption. Feed consumption is influenced by the form of the feed. The best feed to use is high-quality crumble and pellets. Uneven feed increases feed waste. Chicken that consume mash (powdered) feed have more waste, which in this case reduces feed efficiency. It is also stated that grower feed is usually prepared in the form of crumbles.
In addition, in its parent stock pocketbook, it provides a table showing the time to clean the hall according to the feed consumed, which will be reduced by at least half with the consumption of pelleted and crumbled feed. You can see this table below:

All of the above points to the importance of the quality of the feed consumed, as it not only helps to improve performance and reduce costs, but also helps to reduce the work of poultry farm workers.
What is certain is that observing such principles is very effective in the final performance. Therefore, it is recommended that you pay attention to these principles when preparing feed for the poultry farm. In Iran, one of the companies that, in addition to the quality of the materials used, pays attention to all these standards for the production of broiler feed is Jahan Kaveh Company. You can view the product specifications of broiler chickens through the link and finally take action to purchase through email or contact numbers.
Product: High-quality Broiler Feed
Ross Broiler Chicken Rearing Conditions
In addition to using the Aviagen company catalog, we have also prepared an article for you on raising broiler chickens, which can be helpful in this regard. In this article, we have discussed the principles of raising broiler chicken. We have also explained in detail the methods of poultry vaccination and poultry house preparation articles.
How to prepare the poultry house before the arrival of Ross Broiler?
Following the poultry house preparation protocol is one of the most essential factors in raising broiler chickens. Observing the principles of hall preparation has a direct impact on your breeding and profitability at the end of the breeding period. For this reason, we have explained in detail the preparation and disinfection of the poultry house in a comprehensive article.
Daily Feed Consumption Chart for Ross 308 Broiler Chickens: A Guide to Weight Gain
In a poultry farm, achieving the best conditions for broiler chick is crucial. Within just a few weeks, the birds need to be at their peak performance for the farmer to achieve the lowest feed conversion ratio and mortality rate. In line with this, we have provided a comprehensive guide on feed consumption methods, including the average daily feed intake for broiler chickens.
You can also download the Jahan Kaveh company catalog. At the end of the catalog, a guide to the weight gain of Ross broiler chickens along with the per capita consumption of Ross 308 feed is also available.
Jahan Kaveh Broiler Chicken Feed Catalog
At Jahan Kaveh Ofogh Khazar Company, we understand the needs of your broiler chick. We offer a complete diet with all the essential vitamins, minerals, and amino acids. Below, we have provided our recommended feed consumption schedule using Jahan Kaveh broiler feed.
Using high-quality ingredients results in delicious and pure meat with minimal carcass loss, ensuring the best profitability for both the farmer and the slaughterhouse.
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