Lamb Weight Research Articles

Factors affecting birth weight and pre-weaning growth rate of lambs from the Icelandic sheep breed

In Iceland, the sheep production year is characterized by lambing in May, weaning and slaughtering in September and October. Our hypothesis is that modelling interrelationships of production parameters will aid in controlling variation in important outputs like weaning weight. We analyzed data from twelve production years in our experimental farm with total records of 9661lambs born to 1847 dams. In the whole dataset, 7.4 % of the lambs were born as singles, 78.1 % as twins, 13.7 % as triplets and 0.8 % as quads. Surrogate mothers fostered 5.5 % of the lambs.

Maternal lysine, methionine and choline supplementation in twin-bearing Merino ewes during mid-to-late gestation does not alter pregnancy outcomes or progeny growth and survival

High twin lamb mortality in Merino sheep is a major cost for the Australian wool and sheep meat industry. Most lambs die within three days of birth due to low birthweight and/or complications arising during parturition. Maternal arginine supplementation can potentially increase birthweight by improving utero-placental haemodynamics; but availability and cost of rumen-protected arginine are barriers. Therefore, we sought to increase circulating concentrations of arginine, lamb birthweight and survival by supplementing twin-bearing Merino ewes with lysine, methionine and choline from day 80 of gestation (dG 80) to parturition. Each day, ewes were individually fed a supplement (barley, pea, pollard and molasses) with addition of either 14 g lysine, 7 g methionine and 7 g choline (amino acid; AA; n = 48); or no amino acids (control; CTL; n = 48). Supplementation did not alter circulating amino acid profiles in ewes at dG 120. Parturition difficulty of ewes and meconium staining of lambs did not differ between AA and CTL groups. Rectal temperatures during the first 24 h of life and serum IgG concentrations (indicative of colostrum intake) at 24 h after birth were similar in lambs born to AA and CTL ewes. AA supplementation did not alter lamb weights from birth to weaning (~three months of age), or lamb survival to weaning (CTL: 75%; AA: 84.8%, P > 0.05). The lack of response to maternal supplementation with this combination of rumen-protected lysine, methionine and choline suggests that alternate strategies are needed to increase maternal arginine abundance and twin lamb survival.

Effects of Environmental Factors Growth Traits of Akkaraman Sheep in Çankırı Province

Small ruminants are important contributors of food supply chains throughout the world. In this study, characterization of distributions of birth weight, weaning weight, average daily gain and Kleiber ratio as well as estimation of effects of certain environmental factors on these traits were aimed in Akkaraman sheep raised around Çankırı province. For this purpose, the linear mixed model was fitted to estimate the effect of factors and to obtain the least square means for the traits. The effect of all studied fixed factors on birth weight (BW), weaning weight (WW), average daily weight gain (ADWG) and Kleiber ratio (KR) were found to be significant. The male lambs have more BW and WW than female lambs. The least square mean of ADWG for female lambs was found higher than male lambs. Additionally, the least square mean of the pre-weaning growth traits of single-born lambs were found to be higher than that of twin-born lambs. The birth weights of lambs born in January and February were higher than March. In general, the study reported that pre-weaning growth traits were affected by several environmental factors, which can be used for herd management practices aiming for higher productivity in Akkaraman sheep.

Maternal caffeine administration to ewes does not affect perinatal lamb survival

Perinatal mortality of lambs is the major source of reproductive loss in extensive sheep production systems. Treatment with caffeine has reduced intra-partum mortality and/or improved metabolic indicators in other species following hypoxia. This study was conducted to evaluate the efficacy of caffeine for improving perinatal lamb survival. Experiment 1 comprised group-fed Merino ewes grazing pasture and offered 1.8 g/day (estimated 20 mg/kg live weight) caffeine throughout a 4-week lambing period, and a control without caffeine. The survival of lambs to marking (vaccinated, tail docked, males castrated) age in the caffeine treatment group (0.81) did not differ (P = 0.199) from that of control lambs (0.73; total born n = 877). Experiment 2 comprised Merino ewes lambing from three successive weekly joining groups. Treated ewes were drenched with an aqueous caffeine solution at a dose rate of 10 mg/kg live weight from the day before anticipated lambing, until the individual lambed. Control ewes were drenched with water. The proportion of lambs born dead (0.07) and the survival of lambs to marking age (caffeine 0.61; control 0.62) were similar between treatment groups (total born n = 1158). In both experiments, ewe mortality and the weight of lambs at marking were not altered by caffeine treatments. The results from this large-scale field study indicate caffeine is not an effective therapeutic agent to increase either intra-partum or perinatal survival, or lamb growth rates.

Genetic parameters of litter weight, an alternative criterion to prolificacy and pre-weaning weight for selection of French meat sheep

Weight of lambs produced per ewe is an important economic-related trait for French meat sheep farmers. Consequently, genetic improvement of their ewes is based on selecting maternal traits using a global index, called MAT, which combines estimated breeding values for litter size at lambing (LS), weight at 30 days of age (W30D) and viability over the same period. The frame of this study is to compare the official approach to genetic evaluation of maternal traits which combine several estimated breeding values with a direct genetic evaluation of a proxy trait of the farmer's objective. The weight of lambs produced per ewe and per lambing was chosen as this proxy of meat production potential of ewes. In a first step, we estimated the genetic parameters of this alternative criterion, the litter weight (LW), which is the sum of the W30Ds of lambs of the same litter. In a second step, we compared these parameters with those of LS, W30D and MAT, which are routinely used. Datasets comprising 2006–2018 records of 190,883 and 271,963 litters of the Ile de France (IF) and Blanche du Massif Central (BMC) breeds respectively, were analysed. The genetic evaluations were performed using Asreml software according to BLUP animal models, which were the closest to the models used in routine evaluation. Two models are presented: a two-trait model LS and W30D and a two-trait model LS and LW. For LS and LW, records are linked to ewes. For W30D, both direct and maternal effects were considered. Direct animal variance (σ2a_LW = 28.02 for IF and σ2a_LW = 16.55 for BMC) and heritability (h2a_LW = 0.06 for IF and h2a_LW = 0.04 for BMC) of LW suggest it is possible to select based on this trait while simultaneously improving LS (rga_LS/a_LW = 0.78 for IF and rga_LS/a_LW = 0.67 for BMC). Moreover, the genetic progress curves of MAT and LW indicate that the selection based on MAT gave a positive correlated response on LW. Highly correlations between MAT and LW breeding values were estimated (rg = 0.85 for IF and BMC breeds).

EFFECT OF CHLORELLA MICROHYDROGEN SUSPENSION ON PRODUCTIVITY AND GROWTH INTENSITY OF LAMBS

The work was performed in Rozdilnyanske LLC of Rozdilnyansky district of Odessa region. For research, 5 groups of suckling ewes of the Gypsy breed were formed with 10 heads each, one of the groups was a control. Groups were formed by the method of analogue groups taking into account the breed, age in lambs, live weight, which was 50 kg. Chlorella microalgae suspension was fed to ewes in the first 20 days of lactation, in the amount of 3; 5; 7; 9 ml per 1 kg of live weight. Growth intensity, external parameters, and hematological and biochemical composition of blood were determined in newborn lambs at the age of 20 days according to generally accepted methods. It was found that feeding a suspension of chlorella microalgae to lactating ewes at the rate of 3, 5, 7, 9 ml per 1 kg of live weight increases milk productivity by 2.6-4.4 times and live weight of the offspring by 58.8-96.9%, compared to ewes that did not use chlorella microalgae suspension. With an increase in the amount of chlorella microalgae suspension in the diet of lactating ewes, the absolute increase in live weight of their offspring increases by 2.4-4.5 times. The average daily increase in live weight of lambs ranged from 199 g to 339.5 g

Effect of Barley Variety on Feed Intake, Digestibility, Body Weight Gain and Carcass Characteristics in Fattening Lambs.

Simple SummaryUsing a native barley straw as reference, the barley straw from four improved varieties were tested on digestibility and performance in lambs. Differences were observed on feed intake, digestibility, body weight gain and feed-to-gain ratio among lambs fed straws from different barley varieties, pointing to the importance of genetic variation in the feeding value of barley straw.Twenty lambs (18 ± 0.22 kg initial weight) were blocked by weight and individually assigned into pens to evaluate the effects of barley straw variety on digestibility, growth performance and carcass characteristics. The following four treatments were tested: (1) a local barley straw (as control), (2) HB1963 (high grain and straw yields), (3) Traveller (high straw yielder), and (4) IBON174/03 (high grain yielder). A concentrate (50:50 wheat bran and noug seed cake) was offered constantly (300 DM g), whereas the straw was offered ad libitum. The digestibility trial lasted 22 days (15 days to adapt to dietary treatments and 7 days for sampling). The growth performance trial lasted 90 days. At the end, all of the lambs were slaughtered, and their carcasses were evaluated. The IBON174/03 variety had a higher (p < 0.05) intake of organic matter and crude protein, a higher dry matter and organic matter digestibility than the control, and a faster growth than the control. The feed-to-gain ratio was similar among treatments. The slaughter and empty body weights of lambs in the IBON174/03 group were higher than the control variety (p < 0.05). The present study showed that the feeding value of barley straw can differ substantially between varieties and therefore must be considered in the choice of a barley variety.

Single-nucleotide polymorphism detecting of some candidate genes related to lipid metabolism in Booroola Merino-Afshari sheep by Bayesian model averaging

This study was designed to identify single-nucleotide polymorphisms (SNPs) of some candidate genes related to lipid metabolism and their association with carcass fat in male crossbred lambs. Hence, 96 of almost 11-month-old Booroola Merino-Afshari crossbred lambs (first-generation backcross) were used by considering their phenotypic carcass traits. Then, DNA was extracted and DNA targets were amplified using designed specific primers by PCR procedure. Identification of potential SNPs was done by a direct sequencing method for LEP, FABP4, DGAT1, GH, and TRIB3 genes using the sequencing-RFLP procedure. Then, the most probable statistical models based on additive and genotypic effects of identified SNPs in each trait were obtained by the Bayesian model averaging (BMA) approach of R software (Ver. 3.3.1) to assess the association of SNPs with traits. Detected SNPs in this study included two SNPs in exon 3 of LEP, one SNP in exon 2 of TRIB3, one SNP in intron 2 of FABP4, one SNP in 5' UTR of DGAT1, and two SNPs in 3' UTR of GH genes. For carcass weight trait, one of the identified SNP genotypes in the LEP (c.587G > A) had a higher probability in the model. Carcass weight of lambs with GA genotype was 2.46kg heavier than GG genotype. Also, two genes of TRIB3 and GH2 had the highest probability in the models of fat tail and waste weight, respectively. Based on the results, these polymorphisms can be used in the marker-assisted selection of breeding programs and designing DNA chips for genomic selection.

The Effect of Awassi Ewes Body Condition Scores on Milk Production, Composition and Lambs Growth

This study was performed to evaluate the efficacy of body condition scores (BCS) and Sex of lamb on Awassi ewes milk production, composition and lambs growth. The experiment conducted at one of the Awassi sheep breeders in Baibokht area (8km north of Mosul city ) for three months. Ewes were fed concentrate 500g/ewe/day, 60% barley, 38% wheat bran, 1% salt and 1% limestone, with grazing. ewes were divided in to three groups. First group body condition score (BCS 2), the second group (BCS 3) and the third group (BCS 4). The results revealed BCS3 had a significant effect (P<0.05) on weekly milk yield, total milk yield, fat percentage and lambs weight at different ages and no significant effects of BCS on milk Lactose, Protein, total solid and solid non-fat percentage. Sex of lamb had a significant effect (P<0.05) on weekly milk yield and total milk yield and lambs weight from birth until weaning. And no significant effects on milk composition. In general this means that BCS led to significant improvement in the studied traits for behalf highly BCS compared to low. Male lambs had a significant effect on ewes milk yield and lambs weight.

Effect of Dietary Energy Levels on The Performances of Testicular Development, Live Body Weight and Testosterone Concentration in Ouled Djellal Ram Lambs

The aim of our study was to determine the effect of the dietary energy levels on the live body weight, testis volume and blood testosterone concentration in Ouled Djellal ram lambs throughout growth. The study lasted six months from post-weaning until the pubertal period at the Technical Institute Farms (I.T.E.L.V) Lamtar of Sidi-bel-Abbes (Western Algeria). After weaning, Twenty single-born Ouled Djellal ram lambs from 90 to 240 days old were weighed and allotted into two equal groups of Low energy (n = 10) or High energy (n = 10) nutrition plane. Each group received; in addition to a basal diet (good quality pasture) 200 g and 400 g of concentrate feed mixture containing barley (60%), corn (5%), wheat bran (37.5 %) and vitamin-mineral compound (2.5 %) by head-1day-1 respectively. Hay and water were provided ad libitum. Monthly measurements of live body weight, testicular volume and blood testosterone concentration of lambs were recorded. The results showed that the High energy group of lambs recorded a significantly higher live body weight compared to the lambs of low energy group (p <0.001). Whereas, the testicular growth indicated a gradual and linear increase for both groups (low energy and high energy) with significant differences (p <0.001). However, all measurements of the testis, live body weight, serum testosterone levels and age were positively correlated with one another of both low and high groups throughout the experiment. In conclusion, High-level energy supplementation can improve to enhanced development in Ouled Djellal ram lambs this may be due to its beneficial effect on the productive and reproductive performance of growing male lambs. Furthermore, using younger lambs may reduce production costs, accelerate the benefits of genetic selection, and allow earlier progeny and libido testing.

Activity of alkaline phosphatase in male lamb blood serum in relation to age and growth rate

Purpose: to assess the correlation of serum alkaline phosphatase with the live weight and growth rate of male lambs during the milk and post-milk growing periods.Materials and methods. The study of indicators of serum alkaline phosphatase activity in 74 male lambs aged one and five months was carried out in connection with the intensity of growth and the peculiarities of metabolism. All the male lambs were born at the same time and were raised for up to six months under similar feeding and maintenance conditions. To study the dynamics of changes in the live weight of young animals, individual weighing was carried out monthly with an accuracy of 0.1 kg. Based on the results of weighing, the absolute, relative, and average daily live weight gains were calculated and the animals were divided into three groups. The analysis of the serum for the content of the studied parameters was performed by photometry with the help of the corresponding sets of reagents of the company «VitalDiagnostics SPb».Results. During the observation period, the average increase in live weight of male lambs was 21,14 kg, or 136,75 g per day. At one month of age, the activity of alkaline phosphatase was 188,61±9.50 U/l, and at five months — 100,01±3,58, or 47% (P&lt;0,001) lower. It was found that the activity of the enzyme during the suckling period was positively associated with live weight and growth intensity (r=0,35 and 0,49), and after weaning from mothers — negatively (r = -0,46 and -0,46, respectively). The activity of alkaline phosphatase was consistently increased in monthly male lamb when they moved from a group with lower productivity to a larger one — 160,5 — 191,4 — 214,9, and in five-month-olds, on the contrary, decreased — 121,0 — 98,1 — 80,2 E/l. At the age of one month, the increase in growth intensity was accompanied by an increase in the blood serum of male lamb values of gamma-glutamyltranspeptidase, glucose, calcium and phosphorus, and a decrease in urea and cholesterol levels. At the age of five months, both the list of links and their vector changed. In the serum of fast-growing animals, the de Ritis coefficient and gamma-glutamyltranspeptidase were higher, but the activity of lactate dehydrogenase and creatine phosphokinase was lower.Conclusion. The presence of a correlation between alkaline phosphatase and growth makes it possible to use alkaline phosphatase in zootechnical practice and breeding work as an additional criterion for the growth potential of male lambs up to six months in the early stages of ontogenesis. However, the change in the nature of the relationship from plus to minus implies a differentiated approach in the use of this indicator, taking into account the age of the male lambs.

The effects of age, sex, and hot carcass weight on cooked lamb flavor and off-flavor in four muscle cuts.

The present study used 48 lambs originating from three different locations in the Western United States (16 lambs per location; 8 ewes and 8 wethers per location). Each consisting of similar breed composition (Suffolk cross) that were selected to represent weight by age at harvest treatments: light weight carcasses at 5 mo (LW5, 31.81 ± 1.88 kg), light weight carcasses at 12 mo (LW12, 35.09 ± 4.45 kg), heavy weight carcasses at 12 mo (HW12, 57.89 ± 4.70 kg) with different carcass weight compositions. Older heavy weight lambs (HW12) had greater (P ≤ 0.01) hot carcass weight, ribeye area, backfat and body wall thickness, and yield grade compared with light weight lamb carcasses (LW5 and LW12). The longissimus thoracis longissimus thoracis (LT) from older lamb carcasses (LW12 and HW12) had a greater (P ≤ 0.01) total lipid percentage compared with younger lamb carcasses (LW5). Across harvest weight and age treatments, wether carcasses had greater (P ≤ 0.05) total lipid percentage compared with ewe carcasses. Slice shear force values were greater (P ≤ 0.01) for both the LT and semimembranosus from older lambs (LW12 and HW12) compared with LW5 lambs, with no differences between ewes and wethers. Lamb flavor intensity was greater (P ≤ 0.05) for the LT of LW12 lambs and tended (P = 0.08) to be greater for HW12 lambs, compared with the LT from LW5 lambs. The off-flavor intensity of the LT was greater (P ≤ 0.01) for older lambs (LW12 and HW12) compared with LW5 lambs. Interestingly, the lamb flavor and off-flavor intensity scores of the ground shoulder exhibited a treatment × sex interaction. Lamb flavor intensity of LW12 lamb was greater (P ≤ 0.05) from ewes compared with wethers, whereas wethers had a greater (P ≤ 0.05) lamb flavor intensity compared with ewes for HW12 lambs, and LW12 ewe lambs had a greater (P ≤ 0.05) off-flavor intensity compared with all other treatment × sex treatment combinations. Overall, lambs in the present study possessed a mild lamb flavor, typically with greater lamb flavor and off-flavor intensities for older animals; while slice shear force and LT lipid percentage increased as animal age increased at the time of harvest.

PSIII-5 Delaying Weaning Age of Lambs Grazing Chicory (Cichorium Intybus) Increases Body Weight

Abstract Two common challenges in forage-based lamb production systems is the restriction of net energy from grass-based pastures and the production losses associated with parasitic infection. The inclusion of nutrient rich forage in the diet and delaying lamb weaning age has shown to improve lamb growth rates in some systems. The objective of this experiment was to investigate the effects of grazing chicory (Cichorium intybus) and delayed weaning on the growth and health of young pasture-raised lambs. We hypothesized that improving the quality of available forage and delaying weaning would increase the body weight and parasite resilience of lambs. A total of 18 cross-bred ewes and 36 cross-bred lambs (25.2 ± 0.5 kg) were stratified by weight, sex, and randomly assigned to one of two weaning treatments: lambs weaned at 60 days of age (weaned) and lambs remained with their dam and weaned at 120 days of age (delayed weaned). Data were analyzed using PROC MIXED in SAS. Lamb body weight and indices of parasitism were measured every 14 days. There was a treatment × day effect for body weight as delayed weaned lambs were heavier on days 28, 42, and 56 compared with the body weight of weaned lambs (P &amp;lt; 0.02). In addition, there was a treatment × day effect for average daily gain (ADG) whereas delayed weaned lambs demonstrated greater ADG on days 14, 28, 42, and 56 compared with the ADG of weaned lambs (P &amp;lt; 0.02). In monitoring lamb health, there was a treatment × day effect as weaned lambs had a greater packed cell volume (PCV) on day 14 compared with the PCV of delayed weaned lambs (P &amp;lt; 0.03). Conversely, on day 56, weaned lambs had a lower PCV compared with the PCV of delayed wean lambs (P &amp;lt; 0.004). Delayed weaning has shown to be beneficial in improving lamb growth; however, in this instance, delayed weaning demonstrated variable responses in supporting lamb health while grazing on improved pastures.

Evaluation of mathematical models to describe lamb growth during the pre-weaning phase

The aim of this study was to evaluate the use of different mathematical models to describe the growth of lambs during the pre-weaning phase and the effect of sex on their growth curve. Data from 51 lambs (26 males and 25 females) with a genetic constitution of at least 50% Santa Inês breed were used. Lamb weight was monitored during the entire pre-weaning phase (91 days) by weighing the animals weekly on a scale suitable for sheep, to draw the body-weight growth curve. The adequacy of the models was evaluated by the coefficient of determination, simultaneous F-test for parameter identity, concordance correlation coefficient, root mean square error of prediction and decomposition of the mean square error of prediction. Pairwise mean square error of prediction analysis and delta Akaike information criterion were used to compare the models in terms of accuracy and precision. The evaluation of the adequacy of the tested models showed that the data predicted by the linear, quadratic and exponential models were similar (P &gt; 0.05) to the observed data. In contrast, the monomolecular model generated predictions that could not be accepted as true. The linear and quadratic models showed better accuracy and precision. The first-degree linear model should be preferred over the other studied models to describe growth of sheep in the preweaning phase. Males and females exhibited distinct growth patterns.

Productive Performance of Sheep in an Agropastoral System on the Coast of Oaxaca, Mexico

Objective: To determine the prolificacy and weight of lambs at birth (BW) in twogenotypes of hair sheep within an agropastoral system on the coast of Oaxaca, Mexico,and to evaluate the effect of two sources of selenium on the performance of lambs fromsaid system during the fattening phase.Design/Methodology/Approach: The study was carried out in an agropastoral system(coconut palm and Cynodon dactylon grass) in Río Grande, Oaxaca. Two experimentswere conducted; the first studied 58 ewes distributed in a completely randomized design(CRD) with factorial arrangement of 2x2x3, and focused on the following fixed effects:genotype, number of births, and body condition (BC). The measured variables wereprolificacy and BW. The second experiment studied 23 lambs of 4 months in age thatwere offspring of the females in experiment 1. They were distributed in a CRD withthree treatments: T1, without selenium provided; T2, with barium selenate provided; T3,with selenomethionine provided. The dependent variables were daily weight gain(DWG), dry material consumption (DMC), and feed conversion (FC). Results: The Pelibuey ewes with one and two births and the Black Belly ewes with onebirth demonstrated the highest averages in prolificacy (P?0.05). The lowest averages(P?0.05) were detected in ewes with BC 4 irrespective of number of births. The BW wasaffected (P?0.05) by genotype; Black Belly lambs weighed 680 g (P?0.05) more thatPelibuey lambs. The DWG, DMC and FC behaved similarly (P?0.05) betweentreatments and their general averages were 0.114 kg day -1 , 0.679 kg day -1 , and 6.18,respectively.Study Limitations/Implications: In the agropastoral system, the BC of ewes limitstheir reproductive performance. The weight of the lambs at the start of fatteningdetermines their performance during fattening.Findings/Conclusions: In the agropastoral system, Pelibuey and Black Belly femalespresent adequate prolificacy averages and BW; however, it is very important that theyremain within BC 3. Neither of the two sources of selenium improves DWG, DMC, andFC of lambs fattened in pens in the agropastoral system.

Effect of early shearing during gestation on the performance of the progenie

Research has shown the interesting contributions of shearing during mid or late gestation on the performance of lambs from birth to weaning. However, there is no information on the effects of shearing in the first third of pregnancy, on the well-being and productivity of the offspring in adult life. The aim of this study was to investigate whether shearing during the first third of gestation, in a critical time window for the development of the placenta and the fetus, can influence the live weight at parturition, weaning and the survival of the lambs. Additionally, it was studied whether shearing in the first third of gestation is capable of programming metabolic and physiological modifications in the fetus that affect the growth, health and reproductive performance in the adult life of the offspring. Shearing in the first third of gestation significantly increased birth weight of single lambs (P = 0.004) and twins (P = 0.05). The higher weaning weight (P &lt; 0.0001) was related to the higher daily live weight gain (P ˂ 0.0001) in birth-weaning period. The extension of the gestation period (P &lt; 0.0001) explained only 56% and 87% (single and twins) of the increase in total live weight at lambing. Twin lambs from prepartum shorn ewes attempted (P = 0.004) and succeeded in suckling earlier (P = 0.0004) than control lambs. The greater vigor at lambing, together with the greater weight at weaning, may explain the higher (P = 0.04) survival rate. Early prepartum shearing did not affect live weight of ewe lambs from weaning to 18 months old. However, the gastrointestinal parasite egg counts per gram of fecal matter (P = 0.07), as well as the Famacha index (P = 0.02) were significantly lower than in controls. Prepartum shearing affected live weight of male lambs (P = 0.02), although there were no differences in the response to the parasitic challenge. Prepartum shearing did not affect any of the reproductive variables studied in ewes and male lambs. The results of this thesis show that shearing in the first third of gestation is a technique capable of affecting the productive performance of the offspring in the short and long term.

Wool quality and daily weight gain in native lambs from the Central Region of Argentina

The ovine population of the central Argentine territory is the result of constant introductions of different animal biotypes, which determined the existence of ovine populations with great variability. The main objective of the breeders is to produce a lamb for self-consumption and sale of surpluses, without considering the wool product. The production of a lamb for the market is compatible with the production of wool for the textile industry, having to evaluate the feasibility for the commercialization of lamb wool that they produce. This work aimed to provide information and tools to evaluate the quality of lamb’s wool and the evolution of the weight of lambs belonging to the native flocks of the area. Characterization of the productive systems was carried out, seeking to highlight the attributes of meat and wool of native lambs. The characteristics of wool and meat lamb product were evaluated under two treatments, either in free rage conditions or lambs supplemented under confinement. The analysis of the behaviour of the productive systems did not show significant differences between lamb biotypes, which allows affirming that the variation within an animal biotype is even more important than the expected one between biotypes. This indicates that both treatments can be used according to the particular situation of each productive unit. Therefore, it is possible to produce wool and meat of outstanding quality looking for the goodness of the wool produced and optimizing through proper handling practices the meat product.

Maternal Supply of Fatty Acids during Late Gestation on Offspring's Growth, Metabolism, and Carcass Characteristics in Sheep.

Simple SummaryGrowth is an important factor that drives animal production, and it can be manipulated through maternal nutrition. In ruminants, previous studies suggested that maternal nutrition during late gestation with polyunsaturated fatty acids altered growth, energy metabolism, muscle development, and body composition of the offspring. This study investigates the effect of supplementing different sources of fatty acids during late gestation on offspring energy metabolism and growth during the finishing period. Maternal fatty acid supplementation during late gestation modified growth, insulin sensitivity, and hot carcass weight in lambs; these changes depended on the unsaturation degree of the fatty acid supplement and lamb sex. Hence, fatty acid supplementation of the gestating ewe can potentially have a lifelong impact on offspring’s growth performance and metabolism, and could be used as a possible management alternative to enhanced offspring productivity.Lambs born from dams supplemented with different sources of fatty acids (FA) during late gestation have a different growth rate and plasma glucose concentration. The main objectives of this experiment were to evaluate the effect of supplementing different sources of FA during late gestation on offspring plasma metabolite concentrations, growth, and on a glucose tolerance test (GTT) during the finishing phase. Fifty-four lambs (18 pens, 3 lambs/pen) were born from ewes supplemented during late gestation with one of three treatments: (1) no FA (NF); (2) a source of monounsaturated FA (PDS, 1.01% of Ca salts); or (3) a source of eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) (EDS, 1.01% of Ca salts containing). At birth (day 0), supplementation ceased, and all ewes and lambs were placed in a common pen. On day 60, lambs were weaned, grouped by sex, blocked by body weight (BW), and placed on a common finishing diet for 54 days (FP). One lamb per pen was used for the GTT after the FP. There was a tendency for FA × Sex × Day interaction (p = 0.08) on lamb growth during the finishing period, with PDS females being heavier than PDS males, while EDS males were heavier than EDS females at day 60. There was a tendency for FA × Sex interaction (p = 0.06) for plasma insulin concentration for the GTT. Plasma insulin concentration of wethers increased as FA unsaturation degree increased during the GTT; the opposite happened with the plasma insulin concentration of female lambs. In conclusion, FA supplementation during late gestation tended to modified growth and insulin response to a GTT; these changes differed with the degree of FA unsaturation of the supplement and lamb sex.

Consumer Perceptions of Meat Redness Were Strongly Influenced by Storage and Display Times

Lamb (n = 79) meat colour was scored by 879 untrained consumers using a scale of 0 (brown) to 100 (red). This consumer colour score (CCS) was obtained on m. longissimus lumborum (loin) and m. semimembranosus (topside), stored for short (5–7 days), medium (33–35 days), and long periods (110–112 days) and a retail display time of up to 4 days. Consumers perceived topside to be less red initially and changed from red to brown more rapidly when stored for the long-storage period (p < 0.01). Whereas, the initial CCS of loin samples were similar across the storage periods (p > 0.05). CCS and the instrument measure oxy/met (reflectance of light at wavelengths 630 nm and 580 nm) had a low correlation coefficient of 0.33 (p < 0.01). The propensity for lamb growth and leanness indicated by sire breeding values for lamb weight, eye muscle depth, eye muscle fat depth, and loin intramuscular fat had varied and inconsistent effects on CCS. Therefore, even the selection on CCS.

Body condition score at lambing and performance of Santa Inês ewes with an offspring during lactation

The main objective of this research work was to evaluate the performance of Santa Inês ewes according to their body condition score (BCS) at lambing. Data from 135 adult ewes, with singletons, were used. Ewes were divided into three distinct groups: 1) Bellow average: BCS less than 2.5 points (n = 44); 2) Average: BCS between 2.5 and 3.0 (n = 53); and 3) Above average: BCS greater than 3.0 (n = 38). The scale for BCS varied from 1 (very poor) to 5 (very fat). The individual BW, BCS, metabolic profile, milk production and composition of ewes as well as their lambs’ performance until weaning were considered. Metabolic profile was monitored at -7, +7 and +60 days relative to lambing. It was observed that ewes with higher BCS were also heavier; however, there were no differences among the groups for weights of lambs at birth and weaning (70 days). As there was no difference in milk production and composition, the average daily weight gain of the lambs was also similar for the different BCS groups. The metabolic profile (glucose, ?-hydroxibutyrate, cholesterol, creatinine, urea, hemoglobin, albumin, total protein and aspartate aminotransferase - AST) was also similar among the groups. However, when the metabolic profile was compared among the different physiological stages relative to lambing, some differences were observed. For example, ?-hydroxibutyrate was greater during the peripartum period, and glucose was greater in the lactation phase. As conclusion we could say that even in a situation of poor BCS, Santa Inês ewes have the physiological capacity to adapt themselves to the negative energy balance like those of the periparturient period. It seems that irrespective of the BCS, ewes prioritized lactation and were able to produce enough milk to accordingly nurse their lambs