Early Weaning Research & Trial Results (3/3)

All this week on Table Talk we will be discussing the topic of early weaning.

Our first post concentrated on four key questions when considering early weaning (Access the post here). In our second post we looked at creep feeding as an alternative to early weaning and the use of yard weaning as a strategy, and today we round up the latest research results to you on the topic from across the globe.

***If anyone has Australian-based trial or research results, we would absolutely love to share them.

Effect of early life diet on lamb growth and organ development (New Zealand Society of Animal Production, AS Danso et al.)

This research objective was to examine the impact on lamb growth and organ development when pellets added to milk diet of lamb very early post birth.

The research took place in New Zealand at Massey University. 16 male Suffolk lambs were allowed to suck dams for two days after being born. They were then separated and housed in individual indoor pens. One group received milk replacer only and the second group received milk replaced and ad libitum access to pellets. The lambs were slaughtered at 60 days of age.

They found:

  • Mean pellet intake 125.33g DM/day
  • Addition of pellets to the diet of MP lambs had a significant effect on their LW, empty body weight (EBW), LWG and the hot carcass weights of the lambs
  • Total internal organ weight, stomach and liver sizes were greater in pelleted lambs.
  • Pellet consumption can begin at a very early age to assist with lamb rumen development and early weaning.

Lamb finishing systems with early weaning and controlled suckling Sergio Rodrigo Fernandes et al. – Rev. Ceres)

The aim of this study was to evaluate the performance, carcass traits and the finishing costs of Suffolk lambs in systems with early weaning.

Performance, carcass traits and finishing costs compared in three systems:

  1. Weaned with 22kg BW and supplemented on pasture until slaughter (1)
  2. Weaned with 22kg BW and fed in feedlot until slaughter (2)
  3. Lambs in controlled nursing after 22kg BW and creep fed until slaughter (3) – separated from lambs every day for 6 hours and kept on pasture.

They found:

  • ADG: 224 g/d (1), 386g/d (2), 481 g/d (3)
  • Carcass weights and yields highest for lambs in controlled nursing
  • Finishing costs highest in controlled nursing.
  • Reaching slaughter weight quickest was through high concentrate diet and controlled sucking in feedlot, but did not result in the lowest cost per kg/carcass produced.
  • Weaning in feedlot showed lowest cost per kg carcass.

Early weaning and concentrate supplementation strategies for lamb production on Tifton-85 pasture (Cláudio José Araújo da Silv et al. – Revista Brasileira de Zootecnia)

This research out of Brazil presents some interesting on creep feeding, early weaning and lamb supplementation. The influence of early weaning and supplementation strategies were evaluated in four production systems on Tifton-85 pasture:

  • Suckling lambs not supplemented until slaughter
  • Suckling lambs supplemented with concentrate in creep feeding until slaughter
  • Early-weaned lambs not supplemented until slaughter
  • Early-weaned lambs supplemented with concentrate until slaughter.

The research was carried out in Brazil, where the climate is temperate humid with temperate summer. 60 Suffolk lambs were used.

Average daily gain was higher for lambs in creep feeding (275 g/d) and lower for the weaned and unsupplemented animals (57 g/d). Productivity was higher for weaned and supplemented lambs (21 kg lamb body weight, BW gain/ha/d).

Abrupt weaning type combined to stress during late pregnancy in sheep present economic losses on carcass and low testicular development in lambs (Journal of Animal Behaviour Biometeorol – Fabio Luis Henrique et al)

This study aimed to investigate the effect of progressive or abrupt weaning after the stress during middle and late pregnancy on the performance and development of lambs.

  • 24 male lambs from Santa Ines ewes
  • Pregnant ewes submitted to application of Lipolysaccharides E. coli during 70th day (IG) or 120th day (FG) of pregnancy
  • Lambs born separated into two groups, progressive weaning (PW) or abrupt weaning (AW) at 45 days of age.

They found:

  • FG lambs had lowest carcass weights compared to IG and control
  • Lambs from progressive weaning had higher carcass weight
  • Highest cross margin for control e coli and lowest for FG

Effects of early weaning onto herb-clover mixes on lamb carcass characteristics (New Zealand Journal of Animal Science and Production – HX Wong et al

This research took place in New Zealand at Massey Univerity’s Keeble Farm. The objective was to “compare the carcass characteristics of lambs that were on either a perennial ryegrass-based pasture or herb-clover mixes and weaned at either 8 weeks or 15 weeks of age.”

Ewes and twin lambs (at least 16kg) were allocated to three groups:

  • Lambs with dams on ryegrass-white clover pasture until 15 weeks (GRASS)
  • Lambs with dams on herb-clover mixes (plaintain, chicory, red and white clovers) (HERB)
  • Lambs weaned early (8 weeks) onto herb-clover mixes and dams on GRASS pasture (EARLY)

They found:

  • ADG, soft-tissue depth and muscularity of lambs in EARLY and GRASS lower than HERB
  • Lambs weaned early onto herb-clover mixes had lower growth rates than the lambs not weaned early on herb-clover mixes.
  • Lambs can be weaned at 8 weeks of age onto herb-clover mixes to achieve similar carcass characteristics compared to lambs weaned at 15 weeks of age on GRASS pasture.

Inoculation with Rumen Fluid on Early Weaned Lambs (R.Z. Zhong et al. – Livestock Science)

There is limited literature focused on the direct rumen contents inoculation in early weaned lambs, especially on effects of different type of rumen contents inoculation on growth performance. This research focused on whether this intervention may have a practical value in ruminant production systems.

Thirty weaned male lambs (28 days old) with live weight of 10.3 kg were randomly assigned to one of 3 treatments for a 56 day feeding period to study effects of inoculation with rumen fluid from mature sheep on growth performance and rumen fermentation.

The research found inoculation of 100mL fresh rumen fluid increased average daily gain (ADG), apparent digestibilities of DM and neutral detergent fiber (NDF), while inoculation of lyophilized rumen fluid increased apparent digestibility of fat.

Postweaning Handling Strategies on Lambs (Pascual-Alonso et al. – Journal of Applied Animal Welfare Science)

This research from Spain analysed the effect of post weaning handling strategies on welfare and production traits in lambs. After weaning, 36 lambs were assigned to 3 experimental groups with 12 lambs each (control [C], fattening with gentle human female contact [H], and fattening with 2 adult ewes [E]).

  • the results suggest that the lambs handled gently during the fattening were less reactive and better able to modulate their physiological stress
  • the E group adapted better to acute stress than the C group but was less efficient in modulating chronic stress
  • both treatments showed higher slaughter live weights and better ADGs compared with the control.
  • the use of social enrichment at weaning, especially to establish a positive human-nonhuman animal bond, alleviates lamb weaning stress and improves welfare and performance.

Sex-dependent differences in the effect of early weaning (Polish Journal of Veterinary Sciences, M. Cieslak et al.)

This Polish research focused on understanding the impact of early weaning on hormone secretions in lambs of both sexes and testosterone level in male lambs. It used Polish longwool ewes and compared hormone concentration levels of lambs weaned at 5 weeks, 9 weeks, 12 weeks and 16 weeks.

They found:

  • The cortisol concentrations were greater in control and early weaned female lambs than in male lambs at investigated stages.
  • Weaning at 5 weeks of age resulted in the lover cortisol secretion in male lambs in contrast to the greater cortisol secretion in female lambs at 16 weeks of age.
  • Early weaning results in the sexually dimorphic stress reaction that is more potent and long-lasting in female in contrast to male lambs.
  • In female lambs, the stress reaction of early weaning is strong and long-lasting.