Lambs being raised with artificial and natural methods.

Lamb Rearing Revolution: Balancing Welfare and Weaning Success

Rhea Morgan in Science & Nature August 2025 • 4 min read.

"Discover the secrets to optimizing lamb growth and minimizing stress through innovative suckling strategies. Is total separation the answer, or is there a better way?"

For sheep farmers, optimizing lamb growth and ensuring ewe reproductive efficiency are top priorities. Traditional methods like controlled suckling or complete lamb separation aim to achieve both, allowing ewes to return to their estrous cycle sooner. However, the impact of these methods on lamb development remains a key concern.

While previous studies have explored various suckling strategies, the effects of total lamb separation, combined with supplementary feeding, haven't been fully understood. This raises the question: can we improve lamb performance through artificial rearing while minimizing potential stress?

This article examines research into different suckling schemes—continued, controlled, and total separation—and their impact on the growth, stress levels (measured by cortisol), and overall well-being of Santa Inês lambs. We'll uncover the ideal approach for balancing welfare and weaning success.

Suckling Strategies: Weighing Growth Against Well-being

Lambs being raised with artificial and natural methods.

The research compared three suckling strategies in Santa Inês lambs, focusing on weight gain and cortisol levels as indicators of stress and development:

Here's a breakdown of the methods used:

Continued Suckling: Lambs remained with their mothers full-time until weaning at 60 days.
Controlled Suckling: After an initial period, lambs were separated from their mothers and allowed to suckle twice daily for one-hour sessions.
Total Separation: Lambs were completely separated from their mothers and received milk replacer via bottle feeding.

The study tracked concentrate intake, weight gain, and cortisol levels in each group to determine the effectiveness of each approach. Milk production was measured in ewes undergoing total separation to ensure adequate milk supply for the lambs. Blood samples were collected to measure Cortisol level during start and after 10 days to check stress level of lambs.

Finding the Right Balance for Lamb Welfare and Productivity

The study revealed that lambs subjected to total separation exhibited reduced growth compared to those with continued or controlled suckling, suggesting that this method may not be optimal for intensive sheep farming systems. Single-born lambs demonstrated better growth performance compared to twins.

Interestingly, cortisol levels decreased over time in all groups, indicating that lambs adapted to their respective management practices. This suggests that while total separation may initially cause stress, lambs can adjust over time.

Ultimately, sheep farmers must carefully consider the trade-offs between ewe reproductive efficiency and lamb welfare. While early separation can benefit the ewe, it's crucial to ensure lambs receive adequate nutrition and care to support healthy growth and minimize stress. Further research is needed to refine artificial rearing techniques and optimize lamb performance without compromising their well-being.

About this Article -

This article was crafted using a human-AI hybrid and collaborative approach. AI assisted our team with initial drafting, research insights, identifying key questions, and image generation. Our human editors guided topic selection, defined the angle, structured the content, ensured factual accuracy and relevance, refined the tone, and conducted thorough editing to deliver helpful, high-quality information.See our About page for more information.

This article is based on research published under:

DOI-LINK: 10.1590/s1806-92902016000900007, Alternate LINK

Title: Performance And Serum Cortisol Concentration In Santa Inês Lambs Under Different Suckling Schemes

Subject: Animal Science and Zoology

Journal: Revista Brasileira de Zootecnia

Publisher: FapUNIFESP (SciELO)

Authors: Ana Carolina Alves, Nadja Gomes Alves, Ivan Júnior Ascari, Felipe Barbosa Junqueira, Luciana França Smith Maciel, Iraides Ferreira Furusho Garcia, Renato Ribeiro Lima

Published: 2016-09-01

Everything You Need To Know

What are suckling strategies, and why are they important?

In this context, the term refers to the methods used for rearing lambs, specifically looking at the way they interact with their mothers and receive nourishment. The study investigated three suckling strategies: Continued Suckling, Controlled Suckling, and Total Separation. These strategies are crucial because they directly impact lamb growth, stress levels (measured by Cortisol), and overall well-being. Understanding these strategies helps in finding the ideal approach to balance the welfare of the lambs and the success of weaning. Implications include how different suckling schemes affect lamb performance, the potential for improved lamb growth through artificial rearing, and the overall efficiency of sheep farming systems. The study focused on Santa Inês lambs.

What is Cortisol, and why is it significant in this context?

Cortisol, in this research, is a hormone used as a key indicator of stress levels in lambs. Researchers measured the Cortisol level in blood samples. Elevated levels indicate that the lambs are experiencing stress due to changes in their environment or management practices. The measurement was taken during the start and after 10 days. The significance lies in its ability to quantify the impact of different suckling strategies on the lambs' well-being. By analyzing Cortisol levels, researchers can determine which methods minimize stress and promote healthier development. The implications are that the choice of suckling strategy has a measurable effect on the physiological state of the lambs, which affects their development.

What are the differences between the three suckling strategies?

The three suckling strategies are distinct approaches to how lambs interact with their mothers. Continued Suckling allows lambs to remain with their mothers full-time until weaning at 60 days. Controlled Suckling involves separating lambs from their mothers and allowing them to suckle twice daily for one-hour sessions. Total Separation completely separates lambs from their mothers, with lambs receiving milk replacer via bottle feeding. These differences are important because they directly influence lamb growth, stress levels, and overall well-being. The implications of these strategies can affect the lamb's growth performance, the ewe's reproductive efficiency, and the overall sustainability of sheep farming practices, with the Total Separation strategy being a main point of investigation.

What is Total Separation, and what are its implications?

Total Separation is a suckling strategy where lambs are completely separated from their mothers and are fed milk replacer via bottle feeding. In the context of this study, this method was compared to Continued Suckling and Controlled Suckling to assess its impact on lamb growth, stress levels (measured by Cortisol), and overall well-being. The significance of Total Separation lies in its potential impact on lamb performance and welfare. The implications reveal that total separation might not be optimal for intensive sheep farming systems, as lambs in this group exhibited reduced growth compared to those with continued or controlled suckling. Therefore, this method has serious implications for how sheep farmers manage and rear their lambs.

Why were Santa Inês lambs used in the study?

Santa Inês lambs are the specific breed of sheep used in this study. The research focused on this breed to investigate how different suckling strategies affect their growth, stress levels (measured by Cortisol), and overall well-being. The significance of using a specific breed allows researchers to gather data that is directly applicable to that breed's traits and needs. Implications of this specificity are that the findings and recommendations are most relevant to Santa Inês sheep farmers. While the study provides valuable insights, it's important to note that the results may not be directly transferable to other sheep breeds, as different breeds may respond differently to the same rearing methods. Thus, the study establishes a framework to be customized and replicated.