Performance Of Ewes Research Articles

EVALUACIÓN NUTRICIONAL DE TULE (Typha latifolia) EN LA ALIMENTACIÓN DE OVINOS EN EL ALTIPLANO CENTRAL DE MÉXICO

<p><strong>Background: </strong>Sheep production in central Mexico is an important livestock activity that requires the evaluation of feeding strategies to increase or sustain production in times of feed scarcity. <strong>Objective: </strong>To evaluate the performance of ewes fed diets with different levels of inclusion of <em>Typha latifolia</em>. <strong>Methodology: </strong>Fifteen <em>criollo </em>adult ewes were randomly grouped to receive different levels of tule (<em>Typha latifolia</em>) in their feeding as a complement to grazing. An incomplete randomized block design was employed. Daily live weight gain, intake, and body condition score were evaluated, as well as grassland parameters and the chemical composition of feeds. The experiment lasted 60 days divided in four measurement periods. All ewes were supplemented with a commercial pelleted concentrate. The control group (T1) had 0g DM of tule, 461.75 g DM commercial concentrate, and 8 h grazing; T2 had 116.5g DM of tule, 461.75 g DM commercial concentrate, and 8 h grazing; and T3 had 174.75 g DM of tule, 461.75 g DM commercial concentrate, and 8 h grazing. <strong>Results: </strong>There were significant differences (P<0.05) in DM intake of pasture and <em>Typha latifolia.</em> There were no significant differences among treatments (P>0.05) for initial and final live weight, daily weight gain and body condition score. <strong>Implications: </strong><em>Typha latifolia</em> is an available non-conventional forage source for adult sheep maintenance in the dry season for small-scale systems. <strong>Conclusion: </strong>The inclusion of <em>Typha latifolia </em>in diets for sheep may be a good option for feeding adult ewes in maintenance.</p>

Effect of adding carrots as feed supplementation on reproductive performance in Awassi ewes

The present study was designed to estimate the effect of carrots supplementation on reproductive performance in ewes. Thirty Awassi ewes. Ewes were randomly divided into three equal groups, distributed as 10 ewes for each group. First group consider as control, second group feed 400 g carrot/animal daily, third group feed 800 g carrot/animal daily. Each group were synchronized with intra vaginal sponges and injected with 400 IU of eCG at the time of sponge withdrawal. Estrus ewes were conceived naturally with rams and pregnant ewes were followed until parturition. The results of current study demonstrated that G3 had high estrus response and fertility rate 90% compared with G2 and control 80 and 70% respectively. Fecundity rate increased significant in G3 200% compared to G2 and 125 and 100% respectively. Ewes in G3 showed the highest multiple lambing rate 66.67% compared with G2 25% and control 0%. Blood progesterone concentration was high increasing at the 18th day of estrus in the ewes for G3 and G2 compared with control, also, estrogen level at the day of estrus showed high increasing in G3 compared with G2 and control group. We concluded that carrots fed as a supplementation have essential effect on enhancement of reproductive performance in ewes.

Toxoplasma gondii is not an important contributor to poor reproductive performance of primiparous ewes from southern Australia: a prospective cohort study

BackgroundToxoplasma gondii causes reproductive losses in sheep worldwide, including Australia. The reproductive performance of primiparous ewes is typically lower than for mature, multiparous ewes, and younger ewes are more likely to be immunologically naïve and therefore more susceptible to reproductive disease if T. gondii infection occurs during pregnancy. The aim of this study was to assess the impact of infection with T. gondii on the reproductive performance of primiparous ewes in southern Australia using a prospective cohort study. This will inform the need for targeted control strategies for T. gondii in Australian sheep.ResultsToxoplasma gondii seropositivity using indirect ELISA was detected at 16/28 farms located across southern Australia. Apparent seropositivity to T. gondii was lower in primiparous ewes (1.1, 95% confidence interval (CI) 0.6, 1.8) compared to mature, multiparous ewes (8.1, 95% CI 6.0, 10.5; P < 0.001). Toxoplasma gondii seroconversion during the gestation and lambing period was confirmed for 11/1097 (1.0, 95% CI 0.5, 1.7) of pregnant primiparous ewes that failed to raise a lamb, and 1/161 (0.6, 95% CI 0.1, 2.9) primiparous ewes with confirmed mid-pregnancy abortion.ConclusionsLow frequency of detection of T. gondii seroconversion during gestation and low frequency of seropositivity to T. gondii suggests that toxoplasmosis was not an important contributor to reproductive losses in primiparous ewes on farms located over a wide geographical area in southern Australia.

Effect of supplemental rumen-protected methionine on reproduction and production of Awassi ewes

The effect of rumen-protected methionine (RPM) was investigated in Awassi ewes (0, 3 or 5 g/head/d, n = 20) on reproductive and productive performance (initial body weight [BW] = 70.9 − 71.8 kg, 3 − 5 years). Supplementation started with the flushing feeding regime (at the breeding time) and lasted for 42 d. RPM was reused during the last 60 d of pregnancy and the first 60 d of lactation. RPM increased (p < .05) progesterone concentration with a higher lambing rate at the 5RPM level. The number of lambs born for each ewe exposed to the ram was also higher (p < .05) with 3RPM and 5RPM. Methionine levels in the plasma were greater (p < .05) with RPM mainly at 5RPM level. Birth weights of the lambs were higher (p < .05) with RPM regardless of the level. Contrary to this, weaning weights and rate of gain for lambs were reduced (p < .05) with RPM addition. RPM did not affect milk production of ewes during the first 60 d of lactation or on energy corrected milk and feed to milk ratio. However, milk protein content was increased (p < .05) at the 5RPM level while milk fat content was decreased. Regardless of the level of RPM addition, milk casein content increased (p < .05). At all levels, the effect of RPM on milk fatty acid profile was minor. It can be concluded that supplementing RPM might be a valuable tool to enhance the reproductive and productive performance of ewes during their breeding season.

Effects of Age at First Joining and Ewe Genotype on the Performance of Two-Tooth Ewes and That of Their Progeny to Slaughter.

Simple SummaryEwe replacements are a major cost in prime-lamb production. Many producers do not join replacements at 7 months as they believe that it has a negative effect on two-tooth performance. The effect of age at first joining on the reproductive performance of two-tooth ewes, representing three genotypes, was evaluated as well as the performance of their progeny. Whilst joining at 7 months reduced ewe body weight when joined at 19 months and immediately post joining, body weight at the subsequent lambing was increased, and ewe productivity and progeny performance were unaffected. Ewe genotype significantly influenced litter size and the number of lambs reared per ewe joined but had no effect on progeny performance. The probability of rearing at least one lamb (PR1L) is an indicator of overall efficiency. In the current study, whilst there was no relationship between ewe body weight when joined at 19 months and PR1L, there was a positive relationship between body weight at 7 months and PR1L at 2 years. It is concluded that joining replacements at 7 months does not have a negative impact on the performance of two-tooth ewes. The effects of first-joining age (7 or 19 months) and genotype on ewe performance when joined to lamb at 2 years, and the performance of their progeny, were evaluated using 424 ewes, representing 3 genotypes: Belclare (Bel), Suffolk × Belclare (Suf × Bel) and Suffolk-type (≥75% Suffolk ancestry (Suf75)). Ewes were managed in a grass-based system. Ewes first joined at 7 months were lighter (p < 0.01) at 19 months and immediately post lambing; otherwise, age at first joining had no effects (p > 0.05) on ewes or their progeny and there were no important interactions with genotype. Bel and Suf × Bel had larger litters (p < 0.001) and reared more lambs per ewe joined (p < 0.01) than Suf75. Ewe genotype had no effect (p > 0.05) on proportion failing to lamb, incidence of lambing assistance, lamb mortality, ewe survival to 31 months, or progeny performance. Increasing the body weight of ewes at 7 months of age increased the probability (p < 0.02) of rearing 1 or more lambs at 2 years and there was no interaction with genotype. It is concluded that age at first joining had no negative impact on the performance of ewes or their progeny.

The Effect of Flushing Premating with Spirulina Platensis Supplementation on Ewes Postpartum Estrus

Lactating ewes require high nutrients for basic life requirements and milk production. If not fulfilled, it can have an impact on Negative Energy Balance (NEB) that reduces body weight, Body Condition Score (BCS), and extend the appearance of Postpartum Estrus (PPE). Premating flushing feed is an effort to improve ewe nutrients by adding high nutrition for preparation before mating so that after lambing and suckling, the ewe immediately estrus. This research aimed to evaluate the performance of ewes through premating flushing feeding. The research was conducted at Mendo Galak Farm, Sleman, Yogyakarta. Twenty ewes 2-3 years old with BCS 2-3 divided into two groups; the group with flushing treatment consisted of dried water spinach (Ipomoea reptans poir), concentrate feed with Spirulina sp. (14,92% crude protein, 60,28% total digestible nutrients), and the control group (PS) without Spirulina sp. (crude protein 11,82%, total digestible nutrients 53,20%). Flushing feed was given after a month postpartum as much as 3% dry matter of body weight. The recorded parameter was daily feed consumption, monthly body weight, BCS, and postpartum estrus. The data obtained were tested by an independent T-test with Statistical Product and Service Solution (SPPS ver. 22). The results showed the consumption and digestibility of CP, TDN, and ewe's ADG had a significant difference (P&lt;0.05). Postpartum estrus (PPE) of flushed ewes had no significant difference (P&gt;0.05), 73.90±11.55 vs. 77.60±14.65 days, respectively. The conclusion was that flushing premating treatment with the addition of Spirulina platensis increased the nutrient intake and digestibility of CP, TDN, and ADG but had not shortened on postpartum estrus of lactating ewes.

Effects of restricted nutrition and flushing on reproductive performance and metabolic profiles in sheep

The aim of this study was to assess the impact of dietary restriction during the lactation period on flushing performance and metabolic profiles in sheep. The treatments were performed in a 2 × 2 factorial arrangement with (i) adequate and restricted feeding treatment during lactation and (ii) flushing and control feeding treatment during mating season. Eighty-four Karacabey Merino ewes were divided into two groups for adequate energy (100%) and restricted (70%) at energy requirements for three months of lactation. Each group was also divided into two sub-groups based on flushing diet (AL-F, RL-F; 150%) or control diet (AL-C, RL-C; 100%) during the mating season. Live weight (LW), body condition score (BCS), serum metabolites and hormone concentrations, ovulation rate, estrus performance and lambing performance of ewes were observed. Data from this study showed that average difference (P < 0.001) of LW and BCS between groups were 5.45 kg and 0.54 respectively at the end of lactation. No significant effects of nutritional treatments (P > 0.05) were observed; the average fecundity, litter size and ovulation rates of ewes were 1.30±0.07, 1.44±0.06 and 1.53±0.07 respectively. The onset of estrus was earlier (P = 0.021) in RL-F ewes (7.0 d) than for AL-F, AL-C and RL-C ewes (11.0, 12.2 and 10.9 d respectively). Mean PRG concentration of ewes was lower (P = 0.011) in RL-C group than ewes in AL-C group (1.859±0.266 and 3.143±0.272 ng/ml respectively) at the ram introduction day. Serum biochemical variables blood urea nitrogen (BUN), glucose (GLUC), triglycerides (TGL) and very low density lipoprotein cholesterol (VLDL-CHOL) concentrations- decreased (P < 0.05), while non-esterified fatty acid (NEFA), cholesterol (CHOL), high density lipoprotein cholesterol (HDL-CHOL) and low density lipoprotein cholesterol (LDL-CHOL) concentrations increased (P < 0.05) in the restricted ewes compared with adequate ewes in the different months. In conclusion, in addition to BCS, blood total protein, BUN, GLUC, NEFA and CHOL can be recommended for testing flock metabolic profiles as specific blood metabolites. Flushing did not cause significant differences in reproductive parameters including the ovulation rate. However, the time required for onset of estrus was found to be significantly shorter after the flushing treatment in restricted group of animals.

Lower Reproductive Rate and Lamb Survival Contribute to Lower Lamb Marking Rate in Maiden Ewes Compared to Multiparous Ewes.

Simple SummaryThe reproductive performance of ewes in their first breeding season (maiden ewes) can be poorer and more variable than at subsequent breeding seasons. However, the extent and causes of the poorer reproductive performance of maiden ewes on Australian sheep farms are not well understood. We used a survey of Australian sheep farmers to compare the reproductive performance of maiden ewes in their first breeding season to multiparous ewes (ewes that have been bred two or more times) on the same farms. We found that the difference in lamb marking rate between non-Merino ewe lambs and multiparous ewes on the same farm was 58%, and for maiden Merino two-tooth ewes, the difference in marking rate compared to multiparous ewes was 22% lower. Poorer reproduction in maiden ewes was due to a combination of poorer reproductive success to mid-pregnancy (reproductive rate), plus poorer survival of lambs between mid-pregnancy and lamb marking. Reproductive performance for maiden Merino two-tooth ewes was correlated with multiparous ewes on the same farm, whereas the reproductive performance of non-Merino ewe lambs was more variable and not associated with the reproductive performance of their multiparous counterparts. The reproductive efficiency of maiden ewes could be improved by addressing factors that improve the reproductive rate and lamb survival between scanning and lamb marking.Suboptimal reproductive performance of maiden (primiparous) ewes remains a source of inefficiency for the Australian sheep industry. However, the extent and causes of the poorer reproductive performance of maiden ewes on Australian sheep farms are not well understood. Here, we show the reproductive performance of maiden ewes relative to their multiparous counterparts on the same farms across Australia using a cohort survey. The difference in marking rate for non-Merino maiden ewe lambs compared to multiparous ewes was 58% (74 vs. 132%; p < 0.001), and this was attributable to a 50% difference in reproductive rate (109 vs. 159%; p < 0.001) and 16% difference in lamb survival to marking (67 vs. 83%; p < 0.001). The difference in marking rate for maiden Merino two-tooth ewes lambing at approximately 2 years-of-age compared to mature multiparous ewes was 22% (80 vs. 102%; p < 0.001) and this was attributable to a 24% difference in reproductive rate (108 vs. 132%; p < 0.001) and 3% difference for lamb survival (75 vs. 78%; p < 0.05). Positive correlations for reproduction traits (reproductive rate, lamb survival and marking rate) between maidens and multiparous ewes were observed for maiden Merino two-tooth ewes (p < 0.001), but these correlations were weak or non-existent for non-Merino ewe lambs. Strategies to improve both reproductive rate and lamb survival can address the poorer and more variable reproductive performance of maiden ewes.

Vicia sativa as a grazed forage for lactating ewes in a temperate grassland production system

AbstractHere, we present research to overcome a current limitation of temperate grassland systems to provide home‐grown, early season protein for lactating ewes—a period of high protein demand in these systems. Traditionally used as a forage crop, there is renewed interest in common vetch (Vicia sativa) due to its ability to grow during low temperatures over‐winter compared to other legumes. We hypothesised that vetch would support the sustainable development of lamb production by reducing reliance on purchased protein typically used in grass‐only systems. A grazing study determined the performance of early lactation ewes and their twin lambs grazing either an Italian ryegrass (IRG) sward or a vetch/IRG (V/IRG) mix over a six‐week period. The experiment comprised replicate plots of two treatments, with 8 ewes, each rearing twin lambs, grazing each plot. Plots were divided into sub‐plots using electric fencing and rotationally grazed. Findings showed i) ewes selectively grazed vetch as evidenced by a drop in vetch percentage by, on average, 10% units between the start and end of grazing; ii) vetch re‐grew when rotationally grazed with a 21– 28‐d rest period, with vetch percentage of the sward increasing 10% units; and iii) grazing lactating ewes on V/IRG improved combined ewe and lamb weights by five weeks post‐lambing but longer term effects were limited by vetch availability. Furthermore, there was a tendency for lamb live‐weight gains to be higher for lambs whose dams grazed on vetch/IRG compared to IRG swards (573 versus 563 g ewe−1 d−1, respectively, p = 0.056). As the need for alternatives to imported protein feed increases, this research demonstrates how vegetative common vetch, as part of a mixed sward, has the potential to provide a home‐produced winter‐grown protein feed in temperate grasslands.

Various Effects of Concentrate Feed Supplementation at Different Physiological Stages in Madras Red Sheep

Background: Majority of the sheep farmers in our country (semi arid region) do not supplement with concentrate feed even in critical physiological stages. It was observed that concentrate supplementation in addition to free grazing substantially improved production performance of ewes and lambs. Methods: In this study the parameters such as conception rate, birth weight of lambs, fortnightly body weight changes, rumen fermentation pattern and blood parameters were recorded. Result: Out of twenty sheep in each group 16, 18 and 19 were exhibited oestrous symptoms and the percentage of heat observed were 80, 90 and 95 in the G1, G2 and G3, respectively. The numbers of animals conceived were 12, 14 and 17 and the conception percentage was 75, 77 and 89. The concentrate supplemented group showed higher conception rate. The numbers of lambs born were 12, 14 and 17 and the lambing percentages were 75, 78 and 89 for the G1, G2 and G3, respectively. The rumen pH was found to be decreasing in G3 group followed by G2 group when compared to G1 group whereas, the production of VFA was found to be higher in G3 group followed by G2 group when compared to G1 group. There were increased levels of total nitrogen, TCA nitrogen and NP nitrogen in sheep at 4 hours after feeding of concentrate feed in G3 group followed by G2 group when compared to G1 group. The results indicated that the higher levels of blood glucose, triglycerides, cholesterol and BUN were observed in G3 group followed by G2 group when compared to G1 group.

Effects of supplemental lysine and methionine on performance of nursing Awassi ewes fed two levels of dietary protein.

The objective of this study was to investigate the effects of rumen-protected lysine (RPL) and methionine (RPM) supplementation on production performance of nursing ewes fed two levels of dietary protein. Individually housed Awassi ewes (n = 34) nursing single lambs were randomly assigned (2 × 2 factorial design) to one of four dietary treatments with two levels of protein (170 or 151g/kg; HP or MP) and two levels of RPL and RPM (0 or 8.5 plus 4g/day/ewe of RPL and RPM, respectively; no or yes). The trial lasted for 5weeks. Ewes fed the MP diets had (P < 0.01) lower protein intake compared to those fed the HP diets. Intake of other nutrients and milk composition were not significantly (P > 0.13) affected by dietary treatments. Ewes fed the MPYES diet produced more (P < 0.05) milk compared to those fed the MPNO and HPYES diets and tended (P = 0.08) to be more than the HPNO diet. Additionally, milk composition yields for the MPYES diet were significantly (P < 0.05) more than the HPYES diets and tended (P ≤ 0.10) to be more than the MPNO and HPNO diets. Milk efficiency was highest (P < 0.05) for the MPYES diet. Final BW, total gain, and growth rate of lambs were greater when their dams were fed the MPYES diet compared to MPNO and HPNO diets. Under our conditions, decreasing dietary protein from 170 to 151g/kg did not negatively affect the performance of ewes and their lambs. Supplemental RPL and RPM were beneficial for ewes fed diets containing 151g/kg, but not 170, protein.

Effect of GnRH and hCG injection on the reproductive performance and serum progesterone concentration of ewes during spring season.

This study was carried out to investigate the effect of different hormonal programs on the reproductive parameters and serum progesterone concentration of Lake-Ghashghaei ewes in spring season. In this study, 144 ewes were selected from two large nomadic herds. The ewes were synchronized using progesterone sponges. One day before harvesting the sponges, all ewes were injected intramuscularly with 400 IU of eCG. Then ewes were divided into six groups (12 ewes). In the first herd, 1 (GnRH-1 group), 2 (GnRH-2 group), 5 (GnRH-5 group), 7 (GnRH-7 group) and 12 days (GnRH-12 group) after estrus observation, 25.00 µg GnRH was injected intramuscularly to the ewes. In the second herd, the ewes were received 500 IU of hCG on days 1 (hCG-1), 2 (hCG-2), 5 (hCG-5), 7 (hCG-7) and 12 (hCG-12). In each herd, a group of 12 ewes received only eCG and progesterone sponges and was considered as control group. The results showed that twinning rate, the number of born lambs, fecundity and prolificacy rate were higher GnRH and hCG received groups on the second day compared to other groups. The serum progesterone concentration was significantly higher in all groups received GnRH and hCG compared to control group. In general, the results showed that GnRH and hCG two days after mating improved different reproductive activities in addition to increasing serum progesterone concentration. On the other hand, hCG had a greater effect on progesterone concentration, the number of born lambs and the fecundity rate compared to GnRH.

A novel association between hemoglobin subunit beta gene and reproductive performance in Awassi ewes

Abstract This study was performed to assess the polymorphism in the HBB gene and its association with reproductive traits in Awassi ewes. Genomic DNA extracted from 124 and 100 Awassi ewes, respectively, produced single and twins. We amplified three exons in the HBB gene (exon 1, exon 2, and exon 3) to obtain the band (204 bp, 251 bp, and 222 bp) by PCR. Two genotypes were determined in 251 bp amplicon, AA and AG genotypes. Sequencing reactions detected a novel mutation in AG genotype, c.51983514 A > G, with a missense effect of p.K65R. A highly significant (P ≤ 0.01) association of p.K65R SNP with reproductive traits (especially composite reproductive traits, twinning rate, prolificacy and litter size) was reported, in which sheep having p.K65R SNP had a lower composite reproductive traits, twining rate, prolificacy and litter size than those without this SNP. This negative influence of p.K65R SNP was also confirmed by cumulative predictions performed by several in silico tools, which indicated a strongly deleterious impact of p.K65R SNP on hemoglobin. In conclusion, the interesting negative effect of p.K65R SNP has a considerable effect on reproductive performance (especially composite reproductive traits, twinning rate and prolificacy as well as litter size) in Awassi sheep. This manuscript strongly suggests the need to exclude ewes having p.K65R SNP when high values from higher reproductive performance are required.

MTNR1A gene polymorphisms and reproductive recovery after seasonal anoestrus in different Mediterranean sheep breeds

The aims of this study were 1) to investigate the effect of MTNR1A gene polymorphisms on reproductive performance in ewes of one Italian and two Slovenian dairy sheep breeds (Sarda, Istrian Premenka and Boska, respectively) which were located at different latitudes, and 2) to highlight if the different season of the male placement with females that was utilized in the different breeding systems in Sardinia (Italy) and Slovenia resulted in different effects of these polymorphisms on reproductive functions. Reproductively mature ewes (n = 100) from each breed were utilized to conduct the study. To evaluate the reproductive efficiency, lambing dates and number of lambs born were recorded per ewe; additionally, the duration in days from ram placement with ewes to lambing (DRPEL), litter size and the fertility rate were determined based on lambing dates. In each breed, there were eight nucleotide variations within the MTNR1A gene exon II, two of which (g.17355358 and g.17355171), respectively, resulted in a valine to isoleucine, and alanine to aspartic acid substitution, in amino acid sequence. The SNPs at position g.17355452 and g.17355458 were determined to have effects on reproductive performance. Genotypes C/C and C/T at g.17355452 in Bovska and Sarda and genotype A/A at g.17355458 in Istrian Pramenka were associated with a greater fertility and a lesser duration in days from ram placement with ewes to lambing. These findings confirmed that the nucleotide sequences of the MTNR1A gene could affect reproductive functions of Mediterranean sheep.

Influence of feeding different types feed blocks as supplementary feed on the reproductive performance of Awassi ewes grazing cereal stubble

This study was conducted to investigate the Influence of feeding different types feed blocks as supplementary feed on the reproductive performance of Awassi ewes grazing cereal stubble. These types were feed blocks enriched with cottonseed meal (CSM) or Brewers’ grain (BG) as sources undegradable protein (UDP). Ninety-six Awassi ewes (mean live weight 42.2 Kg), aged 3-4 years were allocated into three groups according to ewes live weight and body condition score.Group (C): Control (No Supplement) stubble grazing only.Group (FBC): FB enriched with CSM supplement plus stubble grazing.Group (FBB): FB enriched with BG supplement plus stubble grazing.All ewes were run as one flock during cereal stubble grazing. The feed blocks were fed to animals (supplementary groups) after their return from grazing wheat and barley stubble (28 days prior to mating and 54 days after introduction of rams). Rams run with the flock during the mating period. The results showed that feeding feed blocks enriched with CSM and BG as supplementary feed resulted considerable improvement in weight gain (P&lt;0.05), body condition score (P&lt;0.05), conception rate (13-16), lambing percentage (25-33%), twinning percentage (13-18%) and decreased the proportion of barren ewes (19 vs. 6 and 3%). Inclusion of small amount of high moisture brewers grain by-product (9%) as sources of undegradable protein in the feed blocks formula as replacement for costly cottonseed meal resulted a dramatic effects on the reproductive performance of Awassi ewes especially twinning rates and lambing rate.

Antioxidant capacity, reproductive response and glucose concentration and insulin of ewes supplemented prior to insemination with orange residue

ABSTRACT The objective was to evaluate the antioxidant capacity, glucose and insulin concentration and reproductive performance of ewes supplemented with orange residue prior to insemination. Fifty-five multiparous ewes were divided into two corrals, and 15 unbred ewes were kept individually to measure feed consumption. Two integral diets were administered; T0: control treatment and T1: with 20% of dry matter of orange residue. Ten days after the start of supplementation, the ewes were synchronized. Supplementation was finalized prior to artificial insemination, then, a blood sample was taken to measure the antioxidant capacity and glucose and insulin concentration. An analysis of variance was made to evaluate the effect of treatment on the antioxidant capacity, glucose and insulin; and to analyze the response to estrus, percentage of gestation and prolificity a ji squared test was performed. Of 9 antioxidant compounds found in the orange residue, hesperidin (7.44%), chlorogenic acid (0.50%) and protocatechuic acid had the highest concentration. Feed intake, estrus response, percentage of gestation, antioxidant capacity, and glucose and insulin concentration were not affected by the treatment. It is concluded that inclusion of 20% of orange residue in the diet prior to insemination in ewes is possible.

Seropositivity to Coxiella burnetii in primiparous and multiparous ewes from southern Australia: A cross-sectional study

The role of infectious diseases including coxiellosis in causing poorer reproductive performance of primiparous ewes are not well studied. The aims of this study were to determine if natural exposure to Coxiella burnetii is widespread in breeding ewes and whether seropositivity is associated with poor reproductive performance of primiparous ewes. Seropositivity to Coxiella burnetii was 0.08% (CI95% 0.01, 0.36) in primiparous ewes and 0.36% (CI95% 0.07, 1.14) in mature ewes. Coxiella burnetii was not detected in aborted or stillborn lambs using qPCR. These findings suggest C. burnetii infection was unlikely to be an important contributor to abortion and perinatal mortalities observed for primiparous ewe flocks, and exposure to C. burnetii was not widespread in ewes on farms located over wide geographical region of southern Australia. Whilst ewes on these farms were not an important reservoir for C. burnetii, sporadic zoonotic transmission from sheep is reported and has public health implications.

Feed restriction and supplementing with propylene glycol, monensin sodium and rumen-protected choline chloride in periparturient Ghezel ewes: Implications on production and performance of ewes and their offspring

This study was conducted to evaluate the effects of supplementation of propylene glycol, monensin sodium and rumen-protected choline chloride to the late gestational restricted diet on milk production and composition, rumen fermentation and dry matter intake of ewes and their offspring performance. During the final trimester of pregnancy, 48 Ghezel ewes were randomly assigned to one of the 6 treatments: ad libitum feeding (CG, control); feed restriction (FR, 60% of ad libitum intake); feed restriction + propylene glycol (67 g/d) (FR-PG); feed restriction + propylene glycol + monensin sodium (30 mg/d) (FR-MS); feed restriction + propylene glycol + rumen-protected choline chloride (6 g/d) (FR-RPC); feed restriction + propylene glycol + monensin sodium + rumen-protected choline chloride (FR-PMC). Milk samples were collected during the first 4 weeks of lactation and analyzed for fat, protein and solids non-fat contents. Ruminal fluid was sampled on day 125 of pregnancy for the determination of volatile fatty acids and ammonia-nitrogen concentration. Dry matter intake of ewes was calculated daily according to the differences between feed provided and refused. The average daily gain of lambs was recorded until 30 days postnatal and weight on day 87 was considered as weaning weight. The data were analyzed in a completely randomized design using SAS v.9.3. The results showed that FR-RPC and FR-PMC ewes presented approximately a higher milk production (P < 0.05), milk protein and solids non-fat percentages (P < 0.01) than other ewes in almost all recording points. During the first and second weeks of lactation, the milk produced by FR ewes had the lowest fat percentage among all experimental groups (P < 0.0001). The lowest ruminal pH and ammonia-nitrogen concentration was found in FR and FR-MS ewes (P < 0.0001). Ewes in the CG and FR groups produced lower levels of total volatile fatty acids than other experimental groups (P < 0.0001). Besides, compared with other treatments, choline chloride supplementation caused a higher molar proportion of propionate (P < 0.001) while FR treatment resulted in a higher acetate production (P < 0.001) and acetate to propionate ratio (P < 0.01) compared to FR-RPC and FR-PMC treatments. Lambs born from FR-RPC ewes presented a greater average daily gain than those born from other ewes (P < 0.0001). Lambs reared by FR-PMC and FR ewes presented the highest and lowest weaning weight, respectively (P < 0.0001). It can be concluded that although feed restriction diminished animal production and offspring performance, simultaneous administration of propylene glycol, monensin sodium and rumen-protected choline chloride in restricted diets alleviated these negative effects and improved ewes milk production and offspring growth performance.

Effects of FecB Mutation on Estrus, Ovulation, and Endocrine Characteristics in Small Tail Han Sheep.

The Booroola fecundity gene (FecB) has a mutation that was found to increase the ovulation rate and litter size in Booroola Merino sheep. This mutation is also associated with the fecundity of small-tail han (STH) sheep, an important maternal breed used to produce hybrid offspring for mutton production in China. Previous research showed that the FecB gene affects reproduction in STH sheep, based on litter size records. However, the effects of this gene on estrus, ovulation, and endocrine characteristics in these sheep remain unclear. Here, we analyzed the traits mentioned earlier and compared them among the three FecB genotypes of STH ewes using estrus synchronization. Overall, 53 pluriparous ewes were selected from among 890 STH ewes and subjected to FecB genotyping for experiments to characterize estrous and ovulation rates. FecB heterozygous (+B) ewes presented an earlier onset of estrus (42.9 ± 2.2 h) and a shorter estrous cycle (17.2 ± 0.2 days) (P ≤ 0.05). The ovulation rates increased with the increasing copy number of the B allele (P ≤ 0.01). Ovulation time showed no significant differences among the three FecB genotypes. The serum concentrations of follicle-stimulating hormone (FSH), luteinizing hormone, estrogen (E2), and progesterone (P4) were measured in 19 of the ewes. Serum concentrations of E2 and FSH dramatically varied around the time of behavioral estrus. In FecB mutant homozygous (BB) ewes, E2 concentration had two peaks, which were higher (P ≤ 0.05) than those of ++ genotypes. FSH concentration of BB ewes was higher (P ≤ 0.05) than that of the ++ ewes just after estrus. The expression of the estrogen receptor 1 (ESR1) gene in the +B genotype was higher than in the other genotypes. Based on the data for the reproductive performance of STH ewes with the three FecB genotypes, our study suggests that the development of follicles in ewes with the B allele is dependent on the response to FSH regulated by E2 in the early stage. +B ewes, exhibiting moderate ovulation and litter size and a shorter estrous cycle, can be highly recommended in sheep crossbreeding systems for commercial mutton production. Moreover, this study provides useful information to conserve better and use the genetic resources of STH sheep in China.

Seasonal strategic feed supplements for sheep grazing Caatinga rangeland: Behavior and performance

The objective of this study was to evaluate the impact of concentrate feed supplements associated to seasonal conditions on performance and behavior of ewe grazing Caatinga rangeland from late gestation to lamb weaning. Treatments included supplements at 0, 200, 350 and 500 g concentrate/head/day during the rainy, transition or dry season for 3 years. Supplement during the rainy season stimulated dry matter intake (DMI), digestible protein (DCPI) and total digestible nutrients (TDNI). Feed supplement during the rainy season, when ewes were in their last third of gestation, resulted in greater nutrient offered than required for their elevated nutritional demands, allowing them to utilize forage of better nutritive value when grazing Caatinga rangeland. Greater reproductive efficiency and birth rates resulted. Supplementing feed at 350 g/day or more increased dietary total digestible nutrients (TDN) and crude protein (CP), contributing to greater ewe performance, favoring body weight and condition score maintenance from lambing to lamb weaning while supplementing at 500 g/day during the rainy season increased twinning rates. During the dry season, feed supplement partially substituted rangeland forage but increased overall ewe diet DMI and nutrient digestibility due to greater diet TDN and CP during lamb weaning. Global positioning system data indicated a seasonal impact on ewe behavior and energy use during foraging and seeking out water on semiarid tropical rangeland, notably greater energy expenditure moving during the dry season while ingesting 26.1 % less forage DM that did not meet reproductive requirements. Supplements met this deficit and increased ewe reproductive efficiency.