Seasonal reproductive performance of crossbred ewes in intensive lamb-production systems

Fogarty, NM; Mulholland, JG

doi:10.1071/an12434

Cited by 13 publications

(7 citation statements)

References 45 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The pregnancy rates for autumn-mated Maternal and Merino ewes in the current survey are very similar to previous reports [ 3 , 38 , 39 , 42 ]. Shedding breeds, such as Dorper and Damara breeds, are recognized as being non-seasonal breeders [ 43 ], which explains these results.…”

Section: Discussionsupporting

confidence: 91%

“…Sheep have a seasonal reproductive cycle, becoming most active as photoperiod shortens and experience anestrus or low ovarian activity as photoperiod lengthens [ 1 , 2 ]. Further, the liveweight at which optimal fertility is achieved is influenced by both mating season and breed [ 3 , 4 ]. Adding to variability, breeding season length [ 5 , 6 , 7 ] and ovulation rate are dependent on breed [ 8 , 9 ].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Mating Conditions and Management Practices Influence Pregnancy Scanning Outcomes Differently between Ewe Breeds

Bates

McGrath

Robertson

et al. 2022

Animals

View full text Add to dashboard Cite

Sheep production in southern Australia may vary by breed, time of year, production output (wool, meat, or both), region and seasonal influence. Sheep producers with flocks of approximately 300–500 ewes (n = 58) were recruited across southern Australia to take part in a survey and mating variables were collected from over 30,000 ewes between October 2020 and August 2021. A Bayesian Network (BN) was developed to identify the interrelatedness and most influential variable on pregnancy and fetal number (of pregnant ewes) outcomes under different scenarios. The BN analysis indicated a low association between the variables explored, however, were breed dependent. In wool-based breeds a mating liveweight of 60–69.5 kg predicted the lowest non-pregnant and greatest number of fetuses, and in shedding ewes 70–79.5 kg predicted the lowest non-pregnant rate and 90–99.5 kg the greatest number of fetuses. Pregnancy rate and fetuses per ewe were optimized at ram percentages of 1.5% for Composite and Merino ewes and 2% for Maternal ewes. A mating BCS 4 resulted in greatest pregnancy rate and number of fetuses across all breeds. Curvilinear relationships between mating liveweight, BCS and ram percentage were observed with pregnancy rate and fetal number. Practically, reproductive potential is best managed on a breed basis and with consideration of all variables explored.

show abstract

Section: Discussionsupporting

confidence: 91%

Section: Introductionmentioning

confidence: 99%

Mating Conditions and Management Practices Influence Pregnancy Scanning Outcomes Differently between Ewe Breeds

Bates

McGrath

Robertson

et al. 2022

Animals

View full text Add to dashboard Cite

show abstract

“…Maternal traits that affect the production of weaned lambs are ovulation, fertilization and gestation efficiency, and maternal ability to raise the lamb thereafter (Snowder and Foggarty, 2009;Leeds et al, 2012). Seasonality, by facilitating the access to the markets (Notter, 2002;Kleemann et al, 2006) and carcass traits using terminal sires will add value to the lambs (Fogarty and Milholland, 2014 Basic information on the reproductive potential of any breed is required to establish sound procedures for reproductive management including the application of assisted reproductive technology (Notter, 2002;Lupton, 2008;Delgadillo et al, 2014). The present study aimed to characterize the reproductive function of average Highlander sheep.…”

Section: Introductionmentioning

confidence: 98%

Characterization of the productive performance of Highlander sheep in Southern Chile. I. Female reproductive traits

Cox

Jeria

Bocic

et al. 2015

Small Ruminant Research

View full text Add to dashboard Cite

“…Significant seasonal and breed interactions have been observed with regard to joining time in Hyfer and Border Leicester x Merino (BLM) ewes (Fogarty & Mulholland 2014). While an autumn joining produced the highest fertility and litter size in both breeds, the seasonal effects in the Hyfer ewes were noted as markedly reduced compared to their BLM counterparts (Fogarty & Mulholland 2014).…”

Section: A L Batesmentioning

confidence: 98%

Abstracts from the Proceedings of the 33rd Biennial Conference of the Australian Association of Animal Sciences

2021

Anim. Prod. Sci.

View full text Add to dashboard Cite

During the career of Professor Eric Underwood, the feeding of livestock was closely linked to the availability of local resources. He solved problems by making the connections between the nutrient content of soil and livestock health, but while his research had global impact, I am sure he didn't foresee either the scale of the global feed trade or the environmental impact that livestock systems would have on the world 50 years on from his retirement in 1970.The livestock industry in 2020 is very different from what it was in 1970: global meat production is ~336 million tonnes per year (FAOSTAT averaged over 2016, 17 and 18) compared to the 92 million tonnes produced globally 50 years before. In Australia, the proportional contribution (by weight) of sheep and goat meat to total meat production has decreased from 35 to 16% over that time period and the annual import (mainly from Argentina) of soybean cake in 2016-18 averaged 743,000 tonnes out of a total of 895,000 tonnes of imported feed. Thus, even with Australia's land mass, feeding its livestock sector has a long-range footprint.As we know, livestock production also has global impact through the emission of greenhouse gases (GHGs) into the atmosphere -the relationship also influenced by diet. Gerber et al. (2013) published an extensive assessment of the global contribution of emissions of GHGs from the livestock sector in 2013: beef and cattle milk production accounted for 41 and 20% of the emissions, while pig meat and poultry meat and eggs contributed 9 and 8% respectively. The expansion of pasture and feed crops into forests accounted for 9%.Awareness of the negative environmental impacts of livestock production systems started to become an important topic for research in the 1990s, as policies to limit the environmental impact of agriculture were introduced (e.g. Nitrate Vulnerable Zones in the European Union). The publication of Livestock's Long Shadow in 2006 raised global awareness of the long-range environmental impacts of livestock production systems and since then millions of dollars have been invested in quantifying those impacts. Looking at agricultural production simply through an environmental lens is not sufficient though, since global agreement to the 2030 Agenda for Sustainable Development with 17 Sustainable Development Goals (SDGs). These goals are to be delivered as a package and include 'zero hunger' and 'economic growth', both goals to which livestock production makes a significant contribution (Mehrabi et al. 2020).Research questions thus need to address the potential consequences on all goals, of pathways for making progress towards individual goals. Eric Underwood solved animal health problems through his research, providing solutions based on nutritional knowledge. In the last 50 years animal science has added greatly to that knowledge and supported the development and implementation of technologies which have facilitated the 3.5-fold increase in global meat production. Agriculture and trade policies have also played a significant ro...

show abstract

Seasonal reproductive performance of crossbred ewes in intensive lamb-production systems

Cited by 13 publications

References 45 publications

Mating Conditions and Management Practices Influence Pregnancy Scanning Outcomes Differently between Ewe Breeds

Mating Conditions and Management Practices Influence Pregnancy Scanning Outcomes Differently between Ewe Breeds

Characterization of the productive performance of Highlander sheep in Southern Chile. I. Female reproductive traits

Abstracts from the Proceedings of the 33rd Biennial Conference of the Australian Association of Animal Sciences

Contact Info

Product

Resources

About