Response of plantain (Plantago lanceolata L.) supplementation on nutritional, endo-parasitic, and endocrine status in lambs.

The aim of the present study was to assess the effects of plantain herb (Plantago lanceolata L.) supplementation on growth, plasma metabolites, liver enzymatic activity, hormonal status, gastrointestinal parasites, and carcass characteristics of lambs. A total of 24 lambs, aged 6 months weighing 8.0 ± 0.5 kg were randomly allocated to one of two dietary treatments: (1) CL diet-roadside grass and concentrate mixture; (2) PL diet-CL diet + 5% fresh plantain supplementation on a DM basis. The PL diet group exhibited 23% higher (P = 0.01) average daily gain and 15% improved (P = 0.03) feed conversion efficiency. Circulating cholesterol concentrations were suppressed by 9% (P = 0.03), and liver enzyme activity was improved by 5-25% (P < 0.05) in the lamb fed PL diet, compared with CL diet only. The inclusion of plantain in the diet was highly effective at suppressing the parasites, Paramphistomum spp. (P = 0.003) and coccidial parasites (P = 0.04), but not stomach worms. Moreover, plantain supplementation increased growth hormone and insulin concentrations in plasma level, whereas decreased carcass fat by 32.7%. Therefore, supplementation of the lambs' diet with plantain showed some beneficial effects on productivity and parasitic infection, while it led to a leaner carcass.

Evaluation of tree lucerne (Chamaecytisus palmensis) dried leaves as a substitution for concentrate mixture on biological performance and socioeconomic of Washera sheep fed on desho grass hay.

BACKGROUND: The experiment was conducted to evaluate the effect of tree lucerne dried leaves (TLDL) as a substituting supplement for noug seed cake, and wheat bran concentrate mixtures (CM) on feed intake, digestibility, growth, carcass characteristics and economic benefits using Washera sheep fed desho grass hay as a basal diet. METHODS: Twenty-five male Washera sheep with an initial body weight of 16 ± 4.01 kg (mean ± SD) were used for both growth and digestibility trials which lasted for 90 and 10 days, respectively The experiment was conducted using a randomized complete block design having five blocks with five treatments (T1 = 0% TLDL + 100% CM; T2 = 25% TLDL + 75% CM; T3 = 50% TLDL + 50% CM; T4 = 75% TLDL + 25% CM and T5 = 100% TLDL + 0% CM). RESULTS: Significant (p < .05) differences were observed among treatments in total dry matter (DM), nutrients and metabolizable energy (ME) intake; as the level of TLDL increases total DM and nutrient intake decreased (p < .05) except neutral detergent fibre intake (NDFI) and acid detergent fibre intake (ADFI). Digestibility of DM, organic matter (OM) and crude protein (CP) were significantly reduced (p < .001) among the treatments increasing the substitution level of TLDL for local concentrate mixture, but non-significant for fibre fractions digestibility. Similarly, body weight, average daily gain and feed conversion efficiency were significantly different (p < .01) and highest in T1 than other treatments, whereas lowest values of the same parameters were observed for T5. Non-significant difference among treatments was observed in almost all of the carcass characteristics except for rib-eye area that showed significant difference among treatment and was highest in T1 and T2 (low level of TLDL inclusion). The economic analysis showed that supplementation TLDL was economically feasible in which the net return of the treatments were 31.66 (T1), 30.68 (T2) and 30.34 (T3), 27.88 (T4) and 26.32 (T5) USD (United States Dollar). CONCLUSIONS: It was concluded that TLDL could be used as alternative feed source by replacing concentrate mixture up to 75% (T4) which enhanced nutrient intake, digestibility and growth performance of Washera sheep. Finally, TLDL supplementation is recommended as replacement of CM up to 75% for its biological and economic feasibility.

Free ferulic acid supplementation of heat-stressed hair ewe lambs: Oxidative status, feedlot performance, carcass traits and meat quality.

Twenty-two Katahdin × Dorper ewe lambs (average weight = 23.5 ± 2.8 kg) were individually housed during a 40-d feeding study and then slaughtered to evaluate effects of free ferulic acid (FA; 0 and 250 mg/kg of feed) on oxidative status, feedlot growth, carcass and non-carcass traits, wholesale cut yields and meat quality under heat stress conditions. Overall feeding FA decreased protein oxidation without affecting oxidative stress index, while growth rate and feed efficiency increased only in the hottest period (i.e., 28 to 45 °C). The FA supplementation increased kidney-pelvic-heart and mesenteric fat deposition, as well as yields of forequarter, shoulder, ribs, loin, and breast and flank, but decreased yields of hindquarter, neck, plain loin and leg. Carcass characteristics and meat quality were unaffected by FA. Overall, FA supplementation of heat-stressed hair ewe lambs enhanced feedlot performance under extreme heat stress and increased internal fat reserves, while changing muscle mass deposition, possibly because it prevented protein oxidation.

Inclusion of ripe mango as a source of energy in diets for Creole lambs in the dry tropics.

The aim of this investigation was to evaluate the use of ripe mango as a source of energy in an integral diet consisting of regional products for fattening lambs. Twenty-seven Creole lambs were used and given a 10-day period to adapt to the diet. Three treatments were evaluated: T1 = 40% mango; T2 = 50% mango; and T3 = control diet. In the in vitro analysis, partial and accumulated production of biogas and methane, degradation of dry matter, and neutral detergent fiber were determined. In the in vivo analysis, dry matter intake (DMI), daily weight gain (DWG), apparent digestibility of nutrients, and ruminal characteristics were estimated. The experimental design was completely random. The in vitro results helped hypothesize that the diets with low fiber content would not affect potential dry matter intake. With the exception of the protozoa count, ruminal characteristics were not different among diets (p > 0.05). In productive response, T3 was 13.73% higher DMI than T1, which was 32.24% higher than T2. T3 promoted 61.22% more DWG than T1 and T2. T2 displayed better digestibility of dry matter, organic matter, neutral detergent fiber, and crude protein than T3 (p < 0.05). Fattening lambs fed rations that contain 40% and 50% mango reduces the dry matter intake and daily weight gain relative to the control, although apparent digestibility is higher than for the control diet.

Growth-promoting effect of water-washed neem (Azadirachta indica A. Juss) fruit inclusion in West African dwarf rams.

In a study to determine the growth-promoting effect of water-washed neem (Azadirachta indica A. Juss) fruit (WN) in West African Dwarf (WAD) rams, a total mixed ration was formulated with 0 (WN0), 2.5 (WN2.5), 5.0 (WN5), 7.5 (WN7.5), and 10.0 (WN10) % of WN inclusion. Twenty-five yearling rams (12.3 ± 2.0 kg) were assigned to one of the five dietary groups with five animals per group in a completely randomized design. Each group received the diet for 90 days inclusive of the initial 28 days used for anticoccidial efficacy trial. After the growth trial, three rams from each group were used for digestibility and nitrogen metabolism trial. Anticoccidial efficacy linearly increased (P = 0.002) with increased inclusion of WN and duration of feeding (P = 0.003). Feed intake (P = 0.018) and weight gain (P = 0.009) quadratically increased with WN5 inclusion compared to WN10. Optimal inclusion level of WN for daily weight gain was 5.1% (R2 = 0.30). Digestibility of crude protein was linearly and quadratically increased (P = 0.032; P = 0.031, respectively) with up to WN7.5 inclusion. Nitrogen retention was similar among the treatments. Incorporation of water-washed neem fruit in the diets of West African dwarf rams improved nutrient utilization and animal health by increasing anticoccidial efficacy, feed intake, and weight gain. This is an indication that water-washed neem fruit could be used as growth promoter in sheep production.

Expression of genes for Kisspeptin (KISS1), Neurokinin B (TAC3), Prodynorphin (PDYN), and gonadotropin inhibitory hormone (RFRP) across natural puberty in ewes.

Expression of particular genes in hypothami of ewes was measured across the natural pubertal transition by in situ hybridization. The ewes were allocated to three groups (n = 4); prepubertal, postpubertal and postpubertally gonadectomized (GDX). Prepubertal sheep were euthanized at 20 weeks of age and postpubertal animals at 32 weeks. GDX sheep were also euthanized at 32 weeks, 1 week after surgery. Expression of KISS1, TAC3, PDYN in the arcuate nucleus (ARC), RFRP in the dorsomedial hypothalamus and GNRH1 in the preoptic area was quantified on a cellular basis. KISS1R expression by GNRH1 cells was quantified by double-label in situ hybridization. Across puberty, detectable KISS1 cell number increased in the caudal ARC and whilst PDYN cell numbers were low, numbers increased in the rostral ARC. TAC3 expression did not change but RFRP expression/cell was reduced across puberty. There was no change across puberty in the number of GNRH1 cells that expressed the kisspeptin receptor (KISS1R). GDX shortly after puberty did not increase expression of any of the genes of interest. We conclude that KISS1 expression in the ARC increases during puberty in ewes and this may be a causative factor in the pubertal activation of the reproductive axis. A reduction in expression of RFRP may be a factor in the onset of puberty, removing negative tone on GNRH1 cells. The lack of changes in expression of genes following GDX suggest that the effects of gonadal hormones may differ in young and mature animals.

Supplementation of lamb diets with vitamin E and rosemary extracts on meat quality parameters.

BACKGROUND: Supranutritional supplementation of lamb diets with α-tocopherol is an effective method to reduce lipid oxidation and colour deterioration in meat products. However, alternative antioxidant sources have been proposed to replace the supranutritional vitamin E applications. RESULTS: Indoor concentrate-fed Rasa Aragonesa male lambs (n = 480) were supplemented with increasing levels of all-rac-α-tocopheryl acetate (0.25, 0.5, 1.0 g kg-1 compound feed), rosemary extract (0.20, 0.40, or 0.80 g kg-1 compound feed), or rosemary extract embedded in a fat matrix (0.20, 0.40, or 0.80 g kg-1 compound feed) for 14 days before slaughter. The longissimus thoracis et lumborum muscle from three lambs per pen (18 lambs per treatment) were modified-atmosphere packaged (70% O2 + 30% CO2 ) and maintained under retail conditions for 14 days. Supranutritional supplementation with antioxidants had no effect (P > 0.05) on average daily weight gain, feed intake, and feed efficiency. Rosemary extract supplementation (with or without fat embedment) had no effect on lipid oxidation, myoglobin forms, or colour stability parameters, regardless of the dose. All vitamin E supplementation levels significantly affected lipid oxidation, colour stability (L*, C*, and h), myoglobin forms, and meat discoloration parameters compared with non-supplemented lambs. CONCLUSIONS: This study demonstrates that, unlike vitamin E, neither dose nor protection of the rosemary extract had an effect on lipid oxidation or meat colour stability of lambs during the 14 days of storage under retail conditions. © 2020 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Impact of high-concentrate diets with cottonseed associated with calcium lignosulfonate on the metabolic, productive, and carcass characteristics of feedlot lambs.

This study aimed to evaluate the metabolic, productive, and carcass parameters of feedlot lambs fed high-concentrate diets with cottonseed associated with calcium lignosulfonate. Treatments consisted of diets including whole cottonseed, crushed cottonseed, whole cottonseed with lignosulfonate (100 g/kg), crushed cottonseed with lignosulfonate (100 g/kg), and a control diet without cottonseed. Thirty ½ Dorper ½ Santa Inês, non-castrated male lambs with an average live weight of 24.9 ± 3.6 kg and an average age of 3.5 months were evaluated in a completely randomized design. There was no effect (P > 0.05) on the intakes of dry matter, organic matter, crude protein, and non-fibrous carbohydrates. The crushing of cottonseed and association with lignosulfonate increased (P < 0.01) the intake and digestibility of ether extract. No effect was observed (P > 0.05) for the concentrations of urine and plasma urea N, which averaged 616.2 and 108.6 mg/dL, respectively. There was a change (P < 0.01) in nitrogen balance for digested N in g/day. There was no effect (P > 0.05) on the urinary concentration of purine derivatives, except for uric acid excretions (P < 0.05). Lignosulfonate associated with cottonseed provided an average daily gain of 0.293 kg/day, which was higher than the 0.226 kg/day obtained without lignosulfonate, but lower than control (0.302 kg/day), which also showed higher values of carcass yield. High-concentrate diets formulated without cottonseed improve lamb production performance. The use of high-concentrate diets with cottonseed associated with calcium lignosulfonate provides greater weight gains in lambs.

Inclusion of the aerial part and condensed tannin extract from Cistus ladanifer L. in lamb diets - Effects on growth performance, carcass and meat quality and fatty acid composition of intramuscular and subcutaneous fat.

Thirty-six lambs were used to evaluate the effect of three levels of Cistus ladanifer condensed tannins (CT; 0, 1.25 and 2.5%) and two ways of CT supply (C. ladanifer aerial parts and C. ladanifer CT extract) on lamb growth performance, carcass composition, meat quality and FA composition of intramuscular and subcutaneous fat. The basal diet was composed of dehydrated lucerne supplemented with 60 g/kg of soybean oil. The highest amount of CT (2.5%) had detrimental effects on growth performance, particularly when the aerial part of C. ladanifer was used. Conversely, 1.25% CT in diets did not affect growth performance and meat quality, and inclusion of C. ladanifer CT extract in diet at this level increased t11-18:1, but not c9,t11-18:2 content in fat. Feeding C. ladanifer CT extract might be a good approach for enhancing the nutritional value of ruminant fat, but further studies are needed to ensure upregulation of endogenous synthesis of c9,t11-18:2.

Influence of Ascophyllum nodosum algae extract on finishing growth performance and nutrient digestibility of buffalo calves in warm climates.

The present experiment was conducted to investigate the effect of using an extract of Ascophyllum nodosum algae (Tasco®, AN) on feed digestibility and finishing performance of buffalo calves. Twenty-four buffalo calves (263.4 ± 7.1 kg, 6 ± 1.2-month-old) were allocated to three treatments as a completely randomized design. The experimental treatments included (1) basal diet without supplement (control diet, AN0), (2) basal diet supplemented with 1% (AN1), and (3) basal diet supplemented with 2% (AN2). The gas production parameters and digestibility of feed as well as growth performance of buffalo calves were investigated. The gas production parameters of the experimental diets were not affected by treatments. The average feed intake on the whole period of experiment in the control and AN1 was maximum and minimum, respectively. The AN1 buffalo calves had the largest final weight, total weight gain throughout the entire period (day 0 to 75) and from day 30 to 60 of the experiment (P < 0.05). In comparison with the control (i.e., AN0), overall, the feed conversion ratio in AN1 and AN2 calves improved by about 21.4 and 16.3%, with the AN1 indicating the most suitable feed conversion ratio (P < 0.05). In comparison with the control, supplementation of diets with algae extract linearly improved (P < 0.05) the digestibility of nutrients. Data suggested that inclusion of algae extract had the best beneficial effects on the performance and digestibility of nutrients in finishing buffaloes. Therefore, it may be beneficial to use algae extract especially in warm or hot regions of the world such as the Khuzestan province, though more experiment is required to ensure its effect on heat stress.

Understanding the health and production impacts of endemic Chlamydia pecorum infections in lambs.

Lamydia pecorum is a globally recognised livestock pathogen that is capable of causing severe and economically significant diseases such as arthritis in sheep and cattle. Relatively little information is available on the clinical progression of disease and the long-term effects of asymptomatic and symptomatic chlamydiosis in sheep. Recent studies in calves indicate that endemic C. pecorum infections may reduce growth rates. To investigate the clinical health parameters and production impacts of endemic C. pecorum infection in an Australian commercial lamb flock, we performed bimonthly sampling and clinical health assessments on 105 Border Leicester lambs from two to ten months of age. Chlamydial status was investigated via serology and species-specific quantitative PCR. Throughout the study period, conjunctivitis remained a persistent clinical feature while signs of arthritis (e.g. palpable synovial joint effusions) resolved in a subset of lambs while persisting in others. Clinical disease and C. pecorum infection were highest at six months of age (weaning). As previously reported, peak seroconversion tends to occur two months after the onset of clinical symptoms (6 months of age), with lambs clearing chlamydial infection by 10 months of age, despite ongoing disease still being present at this time. Notably, the presence of chlamydial infection did not affect lamb mass or growth rates throughout the study. At necropsy, C. pecorum was not detected within the joints of lambs with chronic arthritis. Molecular analysis of the strains in this flock suggest that the infecting strains circulating in this flock are clonal C. pecorum pathotypes, denoted ST 23, commonly associated with conjunctivitis and polyarthritis in Australian sheep. This study provides a platform for further research in the epidemiology and disease transmission dynamics of C. pecorum infections in sheep.

Influence of Nigella sativa seeds, Rosmarinus officinalis leaves and their combination on growth performance, immune response and rumen metabolism in Dorper lambs.

The objective of this study was to determine the effects of dietary supplementation of Nigella sativa L. seeds, Rosmarinus officinalis L. leaves and their combination on rumen metabolism, nutrient intake and digestibility, growth performance, immune response and blood metabolites in Dorper lambs. Twenty-four entire male Dorper lambs (18.68 ± 0.6 kg, 4-5 months old) were randomly assigned to a concentrate mixture containing on a dry matter basis either, no supplement (control, T1), 1% R. officinalis leaves (T2), 1% N. sativa seeds (T3) or 1% R. officinalis leaves +1% N. sativa seeds (T4). The lambs had ad libitum access to urea-treated rice straw (UTRS) and were raised for 90 days. Supplemented lambs had greater (P < 0.05) intake of DM and UTRS than the control lambs. The T4 lambs had lower (P < 0.05) nutrient digestibility than those fed other treatments. Total and daily weight gain was greater (P < 0.05) in T2 lambs than those fed other diets. The T3 and T4 lambs had greater (P < 0.05) ruminal pH than the T1 and T2 lambs. Supplemented lambs had lower (P < 0.05) ruminal total volatile fatty acids, acetate, propionate, NH3-N and C18:0 than the control lambs. The T4 lambs had lower (P < 0.05) population of Fibrobacter succinogenes, Ruminococcus albus, methanogens and total protozoa compared with those fed other diets. Supplemented lambs had lower (P < 0.05) neutrophils, basophils and serum urea and greater (P < 0.05) serum IgA and IgG compared with the control lambs. The current results emphasised the variation in the efficacy of medicinal plants in ruminant nutrition.

Nutritional enhancement of sheep meat fatty acid profile for human health and wellbeing.

Dietary fatty acids (FA) consumed by sheep, like other ruminants, can undergo biohydrogenation resulting in high proportions of saturated FA (SFA) in meat. Biohydrogenation is typically less extensive in sheep than cattle, and consequently, sheep meat can contain higher proportions of omega (n)-3 polyunsaturated FA (PUFA), and PUFA biohydrogenation intermediates (PUFA-BHI) including conjugated linoleic acid (CLA) and trans-monounsaturated FAs (t-MUFA). Sheep meat is also noted for having characteristically higher contents of branched chain FA (BCFA). From a human health and wellness perspective, some SFA and trans-MUFA have been found to negatively affect blood lipid profiles, and are associated with increased risk of cardiovascular disease (CVD). On the other hand, n-3 PUFA, BCFA and some PUFA-BHI may have many potential beneficial effects on human health and wellbeing. In particular, vaccenic acid (VA), rumenic acid (RA) and BCFA may have potential for protecting against cancer and inflammatory disorders among other human health benefits. Several innovative strategies have been evaluated for their potential to enrich sheep meat with FA which may have human health benefits. To this end, dietary manipulation has been found to be the most effective strategy of improving the FA profile of sheep meat. However, there is a missing link between the FA profile of sheep meat, human consumption patterns of sheep FA and chronic diseases. The current review provides an overview of the nutritional strategies used to enhance the FA profile of sheep meat for human consumption.

Dietary vitamin E dosage and source affects meat quality parameters in light weight lambs.

BACKGROUND: Supra-nutritional vitamin E supplementation is a commonly used approach to delay lipid oxidation and colour deterioration in lamb and beef meat marketed under modified atmosphere packaging. However, these applications lack a precise calibration of dose for the desired effect and, in addition, limited information is available regarding the use of natural vitamin E for this purpose. RESULTS: Three hundred and sixty Rasa Aragonesa lambs were fed diets supplemented with all-rac-α-tocopheryl acetate (250, 500, 1000 and 2000 mg kg-1 compound feed), RRR-α-tocopheryl acetate (125, 250, 500 and 1000 mg kg-1 compound feed) and a basal diet without vitamin E supplementation for 14 days before slaughter at 25.8 ± 1.67 kg body weight. Vitamin E supplementation had no effect (P > 0.05) on average daily weight gain, feed intake and feed efficiency. Display time had larger effects on lipid oxidation, colour stability, myoglobin forms and meat discolouration parameters compared to vitamin E supplementation. However, vitamin E source and dosage significantly extended meat shelf-life as indicated by lipid oxidation, redness, hue angle, metmyoglobin formation, deoxymyoglobin formation, A580-630 and ISO2 . CONCLUSION: The quantification of these effects demonstrated that the biological activity value of 1.36 used to distinguish both vitamin E sources is not appropriate for meat quality enhancing properties. © 2017 Society of Chemical Industry.

Effect of dietary Tartary buckwheat extract supplementation on growth performance, meat quality and antioxidant activity in ewe lambs.

The objective of this study was to investigate the effect of dietary Tartary buckwheat extract (TBE) supplementation on animal growth performance, meat quality and antioxidative activity in the Longissimus thoracis et lumborum muscle of lambs. The results showed that dietary TBE increased body weight, average daily gain, carcass weight, dry matter intake, and digestive organ weight. Dietary TBE had no effect on the pH, color, shear force or intramuscular fat of Longissimus muscle examined, whereas the cooking loss was decreased. The total antioxidative capacity and glutathione peroxidase 4 (GPx4) activity of Longissimus muscle were increased in lambs fed TBE. The mRNA contents of superoxide dismutase, catalase, GPx4 and nuclear factor-like-2 factor (Nrf2) did not vary among the groups, and greater protein levels of GPx4 and Nrf2 were observed. Taken together, these results suggest that TBE can be used as a feed ingredient in lamb production to improve its growth performance, and relieve oxidative stress and increase water holding capacity of meat.

Effect of dietary supplementation with carnosic acid or vitamin E on animal performance, haematological and immunological characteristics of artificially reared suckling lambs before and after road transport.

To elucidate the influence of dietary carnosic acid (CA) and vitamin E on animal performance, immune response indicators and haematological parameters before and after transport stress, 24 lambs were individually fed ad libitum with milk replacer (MR) using an auto-feeder. Once daily the lambs received MR alone (Group CON, n = 8), MR + 0.096 g CA/kg live weight (LW) (Group CARN, n = 8) or MR + 0.024 g of α-tocopheryl acetate per kg LW (Group VitE, n = 8). After reaching the target slaughter weight (12 ± 0.5 kg), blood samples were collected to measure haematological and immunological parameters. Then, lambs were subjected to 4-h road transport and blood samples were collected again for haematological assessment. The animals were subsequently slaughtered. Before road transport, dietary CA supplementation promoted a descent of circulating white blood cells (WBC), red blood cells (RBC), haematocrit and haemoglobin concentration when compared with Groups CON and VitE (p < 0.05), but it did not affect production of cytokines by blood mononuclear cells. Road transport did not affect either RBC or haematocrit significantly. Nevertheless, transport affected leucocyte profile similarly in all the treatments, increasing granulocytes and monocytes proportions and decreasing lymphocytes. In contrast, after transport, WBC was increased in Group CARN, reaching similar values than Groups CON and VitE. However, under conditions of the present study, those modifications did not influence animal performance or immunity parameters of artificially reared suckling lambs.

Selenium-methionine and chromium-methionine supplementation of sheep around parturition: impacts on dam and offspring performance.

To examine the effects of maternal energy restriction along with selenium-methionine (Se-Met) and chromium-methionine (Cr-Met) supplementation on performance of pregnant sheep and their offspring, the following treatments were allotted randomly to 40 multiparous Baluchi ewes (53.9 ± 1.15 kg of body weight [BW]) from 5 weeks prior to 5 weeks after parturition: (1) Control diet (60% and 100% of NRC energy requirements in pre- and post-partum, respectively); (2) Control diet plus 5 mg Se-Met/kg dry matter (DM); (3) Control diet plus 3 mg Cr-Met/kg DM and (4) Control diet plus 5 mg Se-Met and 3 mg Cr-Met/kg DM (Se-Cr-Met) of concentrate diet. The results indicated that Cr-Met alone or in combination with Se-Met increased average DM intake of ewes. In addition, Group Cr-Met had higher average BW than the Control (p < 0.05). Se-Met and/or Cr-Met supplementation led to decreased average serum cholesterol of the ewes (p < 0.05). Groups Cr-Met and Se-Cr-Met displayed decreased average serum malondialdehyde compared to the Control (p < 0.05). At 24 h post-partum, Group Se-Cr-Met had a greater serum Se content than the Control (p = 0.006). Compared with the Control, the Se concentration in milk was significantly increased from 30 to 138 µg/l and 197 µg/l in Groups Se-Met and Se-Cr-Met, respectively (p < 0.01), which proved that Se-Met supplementation can increase the Se concentration of ewe milk. Furthermore, feeding Cr-Met may attenuate BW loss post-partum and Se-Met and/or Cr-Met supplements may ameliorate oxidative stress condition in ewes around parturition.

Effects of different dietary inclusion levels of macadamia oil cake on growth performance and carcass characteristics in South African mutton merino lambs.

Growth performance and carcass characteristics of South African mutton merino fed graded levels of macadamia oil cake were assessed. A total of 60 South African mutton merino lambs were used in the experiment (initial live weight 25.0 ± 0.45 kg). Five diets with different inclusion levels of macadamia oil cake (MOC) were formulated: T1 (0% MOC, control), T2 (5% MOC), T3 (10% MOC), T4 (15% MOC) and T5 (20% MOC). Effects of inclusion level of MOC on average daily gain (ADG) and average daily feed intake (ADFI) were not significant (P > 0.05). Effects of inclusion levels of MOC on feed conversion ratio (FCR) of sheep were significant (P < 0.05). Highest proportion (71.2%) of sheep in the study had a carcass fat classification of 2, followed by a proportion of 17.3% sheep with a carcass fat classification of 3 and lastly 11.5% sheep had carcass fat classification of 4. Warm and cold carcass mass, chest circumference, carcass length and dressing percentage were higher in sheep fed on 5% MOC compared to other treatment diets (0, 10, 15 and 20% MOC) (P < 0.05). Fat rib eye had a greater area in sheep fed on 5% MOC (P < 0.05). It was concluded that 5% MOC provided the best results in terms of carcass characteristic measurements in sheep.

Brief neonatal nutritional supplementation has sex-specific effects on glucose tolerance and insulin regulating genes in juvenile lambs.

BACKGROUND: The nutritional plane and composition during fetal life can impact upon growth and epigenetic regulation of genes affecting pancreatic ß-cell development and function. However, it is not clear whether ß-cell development can be altered by nutritional factors or growth rate after birth. We therefore investigated the effect of neonatal nutritional supplements on growth, glucose tolerance, and pancreatic development in lambs. METHODS: Newborn lambs were randomized to daily nutritional supplements, calculated to increase macronutrient intake to a similar degree as human breast milk fortifier, or an equivalent volume of water, for 2 wk while continuing to suckle ewe milk. Intravenous glucose tolerance test (IVGTT) was performed at 4 mo of age, and pancreata collected for molecular analysis. RESULTS: Supplemented lambs had slower weight gain than controls. In supplemented lambs, insulin response to IVGTT was increased in males but decreased in females, compared to same sex controls, and was unrelated to growth rate. mRNA expression of key genes in ß-cell development showed sexually dimorphic effects. Epigenetic change occurred in the promotor region of PDX1 gene with decreased suppression and increased activation marks in supplemented lambs of both sexes. CONCLUSION: Nutritional interventions in early life have long-term, sex-specific effects on pancreatic function.

Intravenous maternal -arginine administration to twin-bearing ewes, during late pregnancy, is associated with increased fetal muscle mTOR abundance and postnatal growth in twin female lambs.

The aims of this study were to determine whether parenteral Arg administered to well-fed twin-bearing ewes from 100 to 140 d of pregnancy influences fetal skeletal muscle growth, the abundance and activation of mechanistic target of rapamycin (mTOR) protein, and postnatal muscle growth of the offspring. Ewes fed 100% of NRC-recommended nutrient requirements for twin-bearing ewes were administered an intravenous bolus of either 345 µmol Arg HCl/kg BW or saline solution (Control) 3 times per day. At 140 d of pregnancy (P140), a group of 11 Control and 9 Arg-treated ewes were euthanized and hind leg muscles and longissimus dorsi (LD) were excised and weighed. A sample of LD was snap frozen in liquid nitrogen for later analysis of free AA (FAA) concentration, mTOR abundance and phosphorylation, and biochemical indices (DNA, RNA, and protein content). For the remaining 25 ewes (Arg, = 13, and Control, = 12), Arg administration was continued until the initiation of parturition and ewes were allowed to lamb. Lambs were weaned at postnatal Day 82 and grazed on pasture until postnatal day 153 (PN153), when a subset of 20 lambs ( = 10 per group) was euthanized. At P140, only the psoas major was heavier in the Arg-administered group compared with the Control group. Female lambs from ewes supplemented with Arg (Arg-F) had increased abundance of total mTOR, RNA concentration, and RNA:DNA ratio in LD compared with female lambs from Control ewes (Con-F), whereas males did not differ. At PN153, Arg-F were heavier than Con-F and had heavier LD and plantaris and a trend for heavier psoas major muscles compared with Con-F. In contrast, BW and individual muscle weights did not differ in male lambs. Lambs from Arg-treated ewes had heavier semimembranosus and tended to have heavier biceps femoris compared with Control lambs. The RNA concentration in LD was greater in Arg-F compared with Con-F, and DNA concentration was greater in the Arg group compared with the Control group. In conclusion, Arg administration to the ewe during gestation increases female lamb weight and muscle weight after birth and these changes are associated with altered mTOR protein abundance and have potential implications for sheep production.