Mannheimia haemolytica-associated fibrinonecrotizing abomasitis in lambs.

Mannheimia haemolytica-associated abomasitis has been clinically described as a cause of sudden death in lambs, but it is poorly characterized. We describe the pathological features of a severe fibrinonecrotizing abomasitis in 3 lambs that died suddenly. All 3 abomasums had a thickened submucosa due to edema and necrotic areas delimited by bands of degenerate neutrophils with slender nuclei (oat cells) and angiocentric distributions. The overlying mucosa was congested. Myriads of gram-negative coccobacilli were observed within the oat cell bands. M. haemolytica was isolated from the abomasum in all 3 animals and was serotyped as A2 in one of them. Pericarditis and pleuritis were observed in 2 of the lambs. Clostridium spp. were isolated in 1 lamb and detected by immunohistochemistry in the 3 animals, suggesting clostridial co-infection. M. haemolytica should be considered among the differential diagnoses of necrotizing abomasitis in lambs.

The Effect of Orally Administered Multi-Strain Probiotic Formulation (Lactobacillus, Bifidobacterium) on the Phagocytic Activity and Oxidative Metabolism of Peripheral Blood Granulocytes and Monocytes in Lambs.

Probiotic feed additives have attracted considerable research interest in recent years because the effectiveness of probiotics can differ across microbial strains and the supplemented macroorganisms. The present study was conducted on 16 lambs divided equally into two groups (C-control and E-experimental). The examined lambs were aged 11 days at the beginning of the experiment and 40 days at the end of the experiment. The diet of group E lambs was supplemented with a multi-strain probiotic formulation (Lactobacillus plantarum AMT14, Lactobacillus plantarum AMT4, Lactobacillus rhamnosus AMT15, and Bifidobacterium animalis AMT30), whereas group C lambs did not receive the probiotic additive. At the beginning of the experiment (day 0) and on experimental days 15 and 30, blood was sampled from the jugular vein to determine and compare: phagocytic activity (Phagotest) and oxidative metabolism (Phagoburst) of peripheral blood granulocytes and monocytes by flow cytometry. An analysis of the phagocytic activity of granulocytes and monocytes revealed significantly higher levels of phagocytic activity (expressed as the percentage of phagocytic cells and mean fluorescence intensity) in lambs that were administered the multi-strain probiotic formulation compared with lambs in the control group. The probiotic feed additive also exerted a positive effect on the oxidative metabolism of both granulocytes and monocytes (expressed as the percentage of oxidative metabolism and mean fluorescence intensity) after stimulation with Escherichia coli bacteria and with PMA (4-phorbol-12-ß-myristate-13-acetate). These findings suggest that the tested probiotic formulation may have a positive effect on the immune status of lambs.

Growth performance, nutrient digestion, rumen fermentation and blood biochemistry in response to partially replacing cottonseed cake with sesame meal in a lamb feedlot diet.

Recently, it is necessary to formulate high-quality, balanced and low-cost rations for ruminants from nontraditional sources. The present study conducted to investigate the impact of partially replacing corticated cottonseed (CS) cake with sesame meal (SM) in a lamb feedlot diet on growth performance, nutrient digestion, rumen fermentation and blood biochemistry. Fifteen growing lambs with an initial body weight of 27.4 ± 1.2 kg (6-7 months old) were randomly assigned into three equal groups (n = 5). Lambs in control group (CS) fed a basal diet, while 8% and 16% SM were used to replace an equal portion of corticated CS cake in the second (8SM) and third (16SM) groups respectively. Results showed that most parameters of growth performance and nutrient digestibility were significantly improved (p < 0.05) with the partial replacement of SM (8SM and/or 16SM). Regarding ruminal parameters, ruminal pH and total volatile fatty acids concentration increased (p < 0.05), while ammonia level and total protozoa count decreased with the partial replacement of SM. Moreover, blood parameters showed variant responses to SM partial replacement. Total protein increased, and glucose decreased significantly with 16SM, while cholesterol showed a significant decreasing with both SM replacement levels. SM may substitute CS cake in lamb diet without detrimental effects on performance, digestibility and ruminal fermentation.

The effect of maternal organic manganese supplementation on performance, immunological status, blood biochemical and antioxidant status of Afshari ewes and their newborn lambs in transition period.

It has been documented that adequate maternal manganese (Mn) status is vital for performance and health of ewes and their newborn lambs. However, required level and form of dietary Mn in ruminants are not well defined. The current study was conducted to evaluate the effect of maternal organic Mn supplementation on performance, immunological status, blood biochemical and antioxidant status of Afshari ewes and their newborn lambs in transition period. For this purpose, various organic Mn concentrations were utilized as a supplementary ingredient in formulating the diets of ewes. The ewes were randomly allocated into three groups, fed with 0, and 80 mg/kg organic Mn supplemented diet. At the end of the experiment, the parameters including the performance of newborn lambs, as well as biochemical factors, immune status and antioxidant status in ewes and their newborn lambs were evaluated. The results showed a significant increase in the plasma concentrations of Mn, glucose, insulin, thyroid hormones (T3 , T4 ) and enzymatic antioxidants (SOD, GPX , CAT) in ewes and their newborn lambs that were treated with maternal organic Mn. Moreover, inorganic Mn treatments, the concentration of IgG in newborn lamb's plasma, and colostrum of ewes increased. According to this research, organic Mn acts as a valuable and safe supplementary material that could be exploited for enhancing health of ewes and their newborn lambs.

Wheat germ meal replaces cottonseed meal at different levels in diets of Ossimi lambs: Impact on growth performance, feed utilization and economic efficiency.

This experiment aimed to evaluate the replacement of cottonseed meal (CSM) with wheat germ meal (WGM) in diets of growing lambs on feed utilization and growth performance. Twenty-eight Ossimi male lambs (38 ± 0.8 kg weight), and 180 ± 5 days were divided randomly into four experimental groups in a complete randomized design for 105 days. Cottonseed meal was replaced with WGM at 0 (WGM0 treatment), 50 (WGM50 treatment), 75 (WGM75 treatment) and 100% (WGM100 treatment). The chemical analysis of the total essential and non-essential amino acids showed an increase at the WGM diet compared to CSM. The replacement of CSM with WGM linearly and quadratically improved (p ˂ 0.05) lambs' growth performance and feed conversion. The WGM50 and WGM100 treatments lowered (p ˂ 0.05) feed intake, without affecting nutrient digestibility or diets' nutritive. Feeding WGM increased (p ˂ 0.05) total protein, albumin, and urea-N concentrations in blood of lambs. The WGM100 treatment showed the highest relative percentage of net revenue compared to the other treatments. It is concluded that the complete replacement of CSM with WGM showed positive effects on lambs' performance and economic efficiency.

Nutrient utilization, growth performance, and antioxidative status of Barki lambs fed diets supplemented with black (Nigella sativa) and rocket (Eruca sativa) seeds.

The current study aimed to determine the polyphenol compounds in Nigella sativa (NS) and Eruca sativa (ES) seeds, and evaluate the impact of their addition either as a sole additive or in combination on the growth performance, digestibility, some rumen and blood parameters and antioxidative status of Barki lambs. Forty-eight male lambs (27.18 ± 0.22 kg, 5-6 months), were divided into 4 balanced groups. The experimental diets were randomly distributed to the control group (CON); fed alfalfa hay plus concentrate feed mixture at a ratio of 30:70% without additives, while, NSD, ESD, and NESD groups: fed CON diet plus 2% NS, 2% ES or 1% NS + 1% ES, respectively as a ratio from total mixed ration (TMR). Results indicated that rutin and catechin were the most phenolic compounds observed either in NS or ES seeds. The NS and ES-supplemented groups recorded the highest (P < 0.05) values for dry matter digestibility, nutritive values, average daily gain, and the best feed conversion ratio. However, growth performance, nutritive value, and all nutrient digestibility except for dry matter were not significantly altered with the NESD group. Concentrations of ruminal NH3-N and TVFA were significantly (P < 0.05) reduced with the NESD group, with no significant differences in pH values among different groups. Values of blood parameters showed significant increases in WBCs, PCV, and T-AOC, and decreases in cholesterol, triglycerides, and MDA with the addition of NS and ES seeds or both. Therefore, the addition of NS and ES seeds is recommended to improve lambs' health and antioxidant status.

Effect of urea-treated rice straw, mixed with faba bean straw, on nutrient digestibility, blood metabolites and performance of growing lambs.

The present study aimed to use poor quality roughages, such as rice and faba bean straw, treated with or without urea, and their impacts on digestibility, rumen fermentation, some blood parameters, and growth performance of lambs. Twenty crossbred male lambs (1/4 Finland ×¾ Ossimi, 25±1.13kg live body weight) were chosen and divided into four groups. All lambs were fed rations of concentrated feed mixture at 2% of live weight with the following roughages ad libitum: URS (control group, untreated rice straw), TRS (urea-treated rice straw), FBS (faba bean straw), and TRS+FBS (mixture of TRS and FBS, 1:1). Nutrient digestibility and feeding values improved (P<0.05) with TRS+FBS lambs versus FBS, TRS and URS lambs. The highest numerical values of ruminal total volatile fatty acid (VFA) concentration in TRS lambs were recorded 23.9 ml.eq/dl followed by TRS+FBS, URS and FBS. Regarding to the ruminal parameters, there were no differences (P>0.05) among evaluated groups except for NH3-N, the highest concentration (P<0.05) was recorded in TRS lambs at 3 h post-feeding. Lambs of TRS, FBS and TRS+FBS showed faster growth (P<0.05) than those of the control (i.e., URS). Intakes of dry matter, total digestible nutrients, and digestible crude protein were numerically increased for TRS, FBS, and TRS+FBS. Feed conversion, as kg dry matter/kg gain, was improved for TRS, FBS, and TRS+FBS lambs versus URS. Daily gain of lambs increased (P<0.05) with lambs of TRS, FBS, and TRS+FBS but URS lambs showed a decrease (P<0.05) in daily gain. Feed conversion as kg dry matter intake/kg gain was improved (P<0.05) by feeding on TRS, FBS and TRS+FBS rations versus URS. The TRS+FBS lambs tended to have the highest economic efficiency versus URS, TRS and FBS lambs. It was concluded that urea-treated rice straw could be used as sole roughage or mixed with faba bean straw (1:1) in growing lambs' ration to improve their performance and economic efficiency without adversely affecting their health.The present study aimed to use poor quality roughages, such as rice and faba bean straw, treated with or without urea, and their impacts on digestibility, rumen fermentation, some blood parameters, and growth performance of lambs. Twenty crossbred male lambs (1/4 Finland ×¾ Ossimi, 25±1.13kg live body weight) were chosen and divided into four groups. All lambs were fed rations of concentrated feed mixture at 2% of live weight with the following roughages ad libitum: URS (control group, untreated rice straw), TRS (urea-treated rice straw), FBS (faba bean straw), and TRS+FBS (mixture of TRS and FBS, 1:1). Nutrient digestibility and feeding values improved (P<0.05) with TRS+FBS lambs versus FBS, TRS and URS lambs. The highest numerical values of ruminal total volatile fatty acid (VFA) concentration in TRS lambs were recorded 23.9 ml.eq/dl followed by TRS+FBS, URS and FBS. Regarding to the ruminal parameters, there were no differences (P>0.05) among evaluated groups except for NH3-N, the highest concentration (P<0.05) was recorded in TRS lambs at 3 h post-feeding. Lambs of TRS, FBS and TRS+FBS showed faster growth (P<0.05) than those of the control (i.e., URS). Intakes of dry matter, total digestible nutrients, and digestible crude protein were numerically increased for TRS, FBS, and TRS+FBS. Feed conversion, as kg dry matter/kg gain, was improved for TRS, FBS, and TRS+FBS lambs versus URS. Daily gain of lambs increased (P<0.05) with lambs of TRS, FBS, and TRS+FBS but URS lambs showed a decrease (P<0.05) in daily gain. Feed conversion as kg dry matter intake/kg gain was improved (P<0.05) by feeding on TRS, FBS and TRS+FBS rations versus URS. The TRS+FBS lambs tended to have the highest economic efficiency versus URS, TRS and FBS lambs. It was concluded that urea-treated rice straw could be used as sole roughage or mixed with faba bean straw (1:1) in growing lambs' ration to improve their performance and economic efficiency without adversely affecting their health.

Effect of nonstructural carbohydrates on production performance, rumen metabolism and rumen health in lambs fed with isocaloric and isonitrogenous complete diets.

Nonstructural carbohydrates (NSC) are readily fermentable in the rumen and, are a critical factor while preparing protracted feed for higher animal performance. Four isocaloric and isonitrogenous complete feeds were prepared for this investigation to contain varying levels of nonstructural carbohydrates viz., 40.13 (NSC1), 45.21 (NSC2), 50.00 (NSC3) and 55.85 (NSC4) per cent, respectively. The four isocaloric and isonitrogenous complete feeds were tested in 32 Mecheri ram lambs (around three months of age) in a completely randomised block design (n = 8), and the lambs were fed their respective feed for six months. The study revealed that the increased NSC level in the complete diet increased the body weight and weight gain linearly (P < 0.05). The dietary NSC level affected the dry matter consumption in a quadratic manner (P < 0.05) and the lambs of the NSC4 group consumed significantly (P < 0.05) less DM compared to other dietary groups. The overall average feed conversion efficiency differed significantly (P < 0.05) among dietary groups. The correlation between dietary NSC level and faecal score was quadratic (r2 = 62.7, P < 0.05). The rumen pH, total nitrogen and NH3-N concentration were linearly decreased (P < 0.05) and the molar proportion of total short-chain fatty acids and propionic acid were increased (P < 0.05). The energy loss expressed as methane production was significantly (P < 0.01) lower for the high NSC diet-fed lambs. The lambs fed on a low NSC diet had significantly (P < 0.05) lower carcass weights, dressing percentage and loin eye area. The per cent share of rumen weight in the total fore stomach and the rumen papillae measurements length, width and surface area were significantly (P < 0.05) higher in high NSC diet-fed lambs. Increased levels of NSC in the diet increased (P < 0.05) fat deposition in the internal organs. The saturated fatty acids content in the meat was significantly (P < 0.05) lowered, whereas, the oleic acid and linoleic acid were increased (P < 0.05) as the NSC level increased in the diet. The study revealed that as the level of NSC increased in the complete diet there was a concomitant improvement in the final body weight, ADG and feed efficiency of post-weaned Mecheri lambs. It can therefore be recommended that the complete feed with 50 per cent NSC levels would be optimum to reap maximum returns from fattening Mecheri lambs.

The role of olive leaves and saccharomyces cerevisiae supplementation in enhancing the performance and economic feasibility of fattening lambs.

Objectives were to assess the use of olive leaves (OL) to replace wheat straw, the forage source, and the supplementation of Saccharomyces cerevisiae (SC) on nutritional intake, growth performance, blood parameters, and carcass quality in lambs. A total of twenty-one newly weaned Awassi lambs, weighing an average of 19 ± 0.6 kg, were randomly distributed to three groups. These three diets were: CON: 0% OL control diet; OL diet of 25%; and OL plus 0.4 g SC/head/d (OLSC) diet of 25% of dietary dry matter (DM). The first seven days were devoted to adaptation and the next sixty days were devoted to gathering data. Daily records of nutrient intake were made. On the 49th day of data collection, four animals were randomly selected from each group and kept in individual metabolism cages (1.0 × 0.8 m) with slatted mash for eight days (four days for data collection and four days for cage adaptation) to evaluate N balance and nutrient digestibility. All lambs were slaughtered after the study to assess the quality of the meat and the carcass features. No difference in DM consumption (P > 0.05) between the treatment groups. When OL-containing diets were compared to the CON diet, the consumption of acid detergent fiber and neutral detergent fiber (NDF) was lower (P ≤ 0.0002), whereas metabolizable energy and ether extract were higher (P < 0.0001). While the OL diet was intermediate, the final BW, total gain, and average daily gain for the OLSC diet tended to be higher (P < 0.087) than the CON diet. Lambs fed the OL-containing diets had a lower (P = 0.0020) cost of growth ($US/kg) than lambs in the CON group. All other nutrient digestibilities were comparable between the treatment diets, except NDF digestibility, which was greater (P = 0.045) in the OLSC group than in the CON group. The N balance variables showed a similarity between the various diets (P > 0.05). Lambs fed the OLSC diet tended to have higher weights (P ≤ 0.098) for fasting live weight, hot carcass weight, carcass cuts weights, and cold carcass weight than lambs on the CON diet. The OLSC diet resulted in higher (P < 0.025) loin weight and intermuscular fat in comparison to the CON and OL diets. No difference (P ≥ 0.05) in the dissected tissues between diets. The longissimus dorsi muscle's dimensions and physicochemical characteristics did not alter (P > 0.05) across the treatment diets. In comparison to the CON and OL diets, the OLSC diet resulted in higher serum glucose levels (P = 0.044). Nonetheless, there were similarities (P ≥ 0.05) in various serum blood parameters between the treatment diets. In conclusion, using OL or/and supplemented SC is positively associated with nutrient intake, growth performance, some carcass parameters, and loin cut tissue, and the most effective aspect is decreasing production cost ($US/kg gain), which makes it a good solution to pass inflation feedstuff prices and cover animal needs.

First identification of Cryptosporidium parvum virus 1 (CSpV1) in various subtypes of Cryptosporidium parvum from diarrheic calves, lambs and goat kids from France.

Cryptosporidium spp. remain a major cause of waterborne diarrhea and illness in developing countries and represent a significant burden to farmers worldwide. Cryptosporidium parvum virus 1 (CSpV1), of the genus Cryspovirus, was first reported to be present in the cytoplasm of C. parvum in 1997. Full-length genome sequences have been obtained from C. parvum from Iowa (Iowa), Kansas (KSU) and China. We aimed at characterizing the genome of CSpV1 from France and used sequence analysis from Cryptosporidium isolates to explore whether CSpV1 genome diversity varies over time, with geographical sampling location, C. parvum genetic diversity, or ruminant host species. A total of 123 fecal samples of cattle, sheep and goats were collected from 17 different French departments (57 diseased animal fecal samples and 66 healthy animal fecal samples). Subtyping analysis of the C. parvum isolates revealed the presence of two zoonotic subtype families IIa and IId. Sequence analysis of CSpV1 revealed that all CSpV1 from France, regardless of the subtype of C. parvum (IIaA15G2R1, IIaA17G2R1 and IIdA18G1R1) are more closely related to CSpV1 from Turkey, and cluster on a distinct branch from CSpV1 collected from C. parvum subtype IIaA15G2R1 from Asia and North America. We also found that samples collected on a given year or successive years in a given location are more likely to host the same subtype of C. parvum and the same CSpV1 strain. Yet, there is no distinct clustering of CSpV1 per French department or ruminants, probably due to trade, and transmission of C. parvum among host species. Our results point towards (i) a close association between CSpV1 movement and C. parvum movement, (ii) recent migrations of C. parvum among distantly located departments and (iii) incidental transmission of C. parvum between ruminants. All together, these results provide insightful information regarding CSpV1 evolution and suggest the virus might be used as an epidemiological tracer for C. parvum. Future studies need to investigate CSpV1's role in C. parvum virulence and on subtype ability to infect different species.

Astragalus additive in feed improved serum immune function, rumen fermentation and the microbiota structure of early-weaned lambs.

AIM: The purpose of this study was to determine the mechanism of Astragalus activity on the immune function, rumen microbiota structure, and rumen fermentation of early-weaned lambs. METHODS AND RESULTS: Thirty healthy early-weaned lambs with similar body weights (17.42 ± 2.02 kg) were selected for the feeding experiment. The control group (KB) was fed a basal diet, and the Astragalus group (HQ) was fed 0.3% Astragalus additive on the basis of a basic diet. The formal trial period was 60 days. The results showed that the concentrations of blood immunoglobulin A (IgA) and immunoglobulin M (IgM) in the HQ group were significantly higher than those in the KB group (P < 0.05). Compared with the KB group, the concentrations of acetic acid, butyric acid, and total volatile fatty acids (VFAs) in the HQ group were higher (P < 0.01). The expression levels of the rumen epithelial-related genes MCT1, MCT4, NHE2, and ZO1 in the Astragalus group were significantly higher than those in the KB group (P < 0.05). 16S rRNA analysis showed that at the phylum level, Bacteroidetes in the HQ group significantly increased (P < 0.01); at the genus level, Prevotella (P < 0.01) and Succiniclasticum (P < 0.01) in the HQ group were found at significantly higher abundances than those in the KB group, and the results of microbiota gene and function prediction showed that "energy metabolism," "glycan biosynthesis and metabolic" pathways were significantly enriched in the HQ group (P < 0.05). CONCLUSION: As a feed additive, Astragalus can improve the immunity of early-weaned lambs, the structure of the rumen microbiota of lambs, and the fermentation capacity of the rumen.

Exploring the rumen microbiota of Hu lambs in response to diet with paper mulberry.

Paper mulberry (Broussonetia papyrifera), as a new woody forage with high-protein characteristic, is being widely used in ruminant feeding. However, little is known about the comprehensive microbiota picture of whole ruminal niches (liquid, solid, and epithelium) under paper mulberry diet. To gain a better understanding of feeding paper mulberry on the rumen microbiota, the effects of fresh paper mulberry, paper mulberry silage, or a conventional high-protein alfalfa silage on rumen fermentation products and microbiota in rumen niches of Hu lambs were studied. Forty-five Hu lambs were randomly divided into 3 treatments with 15 replicates in each treatment. No significant difference was observed among treatments in the average daily gain (ADG). The fresh paper mulberry treatment had lower (P < 0.05) pH and higher (P < 0.05) total volatile fatty acids (TVFA) compared with silage treatments, but the fermentation parameters did not show significant differences between paper mulberry silage and alfalfa silage treatments. The Shannon index did not show a significant difference (P < 0.05) among treatments except between fresh paper mulberry and alfalfa silage treatment in rumen epithelial niches. Butyrivibrio and Treponema were the predominant genera in the rumen epithelial fraction, while Prevotella and Rikenellaceae_RC9 dominated in both rumen liquid and solid fractions. These results indicated the paper mulberry supplement did not have distinct impact on the microbial diversity and growth performance compared with alfalfa silage, especially for paper mulberry silage, which might help us develop an alternative animal feeding strategy of replacing alfalfa with paper mulberry. KEY POINTS: • Feeding paper mulberry silage did not show significant impact on the growth performance compared with alfalfa silage treatment. • Feeding fresh paper mulberry reduced rumen pH value and increased total volatile fatty acid. • The microbial diversity did not show significant difference among treatments.

Detection and molecular characterization of Clostridium perfringens, Paeniclostridium sordellii and Clostridium septicum from lambs and goat kids with hemorrhagic abomasitis in Turkey.

BACKGROUND: The pathogenic Clostridia cause neurotoxic, histotoxic and enterotoxic infections in humans and animals. Several Clostridium species have been associated with abomasitis in ruminants. The present study aimed to investigate the frequency, and the presence of virulence genes, of Clostridium perfringens, Paeniclostridium sordellii and Clostridium septicum in lambs and goat kids with hemorrhagic abomasitis. RESULTS: A total of 38 abomasum samples, collected from lambs and goat kids of 1 week to 1 month of age in different farms located in eastern Turkey between 2021 and 2022, were evaluated by histopathology, culture and PCR. At necropsy, the abomasum of the animals was excessively filled with caseinized content and gas, and the abomasum mucosa was hemorrhagic in varying degrees. In histopathological evaluation, acute necrotizing hemorrhagic inflammation was noted in abomasum samples. The examination of swab samples by culture and PCR revealed that C. perfringens type A was the most frequently detected species (86.84%) either alone or in combination with other Clostridium species. P. sordellii, C. perfringens type F and C. septicum were also harboured in the samples, albeit at low rates. Beta2 toxin gene (cpb2) was found in three of C. perfringens type A positive samples. CONCLUSION: It was suggested that vaccination of pregnant animals with toxoid vaccines would be beneficial in terms of protecting newborn animals against Clostridial infections. This study investigated the presence of clostridial toxin genes in abomasal samples for the first time in Turkey.

Effects of starter feeding and early weaning on developmental expressions of IGF-I gene in liver and IGF-IR gene in rumen of lambs from birth to eighty-four days of age.

The early weaning and starter feeding have significant effects on lamb growth and digestive tract development. However, it is not clear whether the expression of IGF-1/IGF-1R genes could be affected by feeding starter and weaning. Therefore, a total of 102 Hu male neonatal lambs were randomly divided into 3 groups: fed with starter at 42d + weaned at 56d (group A), fed with starter at 7d + weaned at 28d (group B) and fed with starter at 7d + weaned at 56d (group C), to explore the effects of starter feeding and weaning age on developmental expressions of IGF-I gene in liver and IGF-IR gene in rumen of Hu sheep. The results showed that IGF-I and IGF-IR genes were expressed extensively in various tissues of lambs, the expression of IGF-I was significantly higher in liver (p < 0.01), while the expression of IGF-IR was higher in rumen among gastrointestinal tissues. The mRNA level of IGF-I of group C was strikingly higher than that of group A at 28, 70, and 84d (p < 0.01) in liver, respectively. Rumen mRNA level of IGF-IR of group C was prominently higher than that of group A at 70d and 84d (p < 0.05), respectively. However, IGF-IR expression of group A was higher than that of group C at 14 and 42d (p < 0.05). The mRNA level of IGF-I of group B was significantly higher than that of group C at 42, 56, 70, and 84d (p < 0.01) in liver, while IGF-IR expression of group B was higher than that of group C at 70d (p < 0.01). In conclusion, early weaning and starter feeding affected liver IGF-I mRNA and rumen IGF-IR mRNA expression.

Dietary rumen-protected choline supplementation regulates blood biochemical profiles and urinary metabolome and improves growth performance of growing lambs.

This study aimed to assess the growth performance and blood metabolites, as well as metabolic profiles in the urine of lambs fed on dietary rumen-protected choline (RPC). Thirty-six Dorper × Hu lambs weighing approximately 20 kg were equally assigned to three groups, and fed on three diets supplemented with different RPC concentrations (0, 0.25% and 0.75%) for 45 days. Supplementation of RPC significantly increased average daily gain (ADG) and decreased feed-to-gain ratio (F/G) of lambs (p < 0.05). Dietary RPC was significantly associated with elevated plasma high-density lipoprotein (HDL) and suppressed low-density lipoprotein (LDL) levels when compared to the control group (p < 0.05). Moreover, concentrations of very-low-density lipoprotein (VLDL) exhibited an increasing trend (p = 0.065), whereas ß-hydroxybutyrate (BHBA) levels decreased (p = 0.086) in plasma. Analysis of urine metabolome revealed that RPC supplementation significantly suppressed urinary concentrations of pyruvate (p < 0.05), while increased urinary concentrations of trimethylamine oxide, p-cresol, phenylacetylglycine and hippurate (p < 0.05). These findings suggest that RPC supplementation can promote weight gain, alter plasma lipid metabolism and modify urinary metabolome which is correlated with energy metabolism, lipid metabolism and intestinal microbial metabolism in lambs. In conclusion, based on our findings, we recommend 0.25% RPC as a supplement for growing lambs.

Variation in the ovine FOXP3 gene and its effect on growth traits in Egyptian Barki sheep.

The aim of the present study was to detect the FOXP3 gene polymorphisms in Barki sheep at a variable region covering exon 13, intron 13 and the coding sequence in exon 14 and to test the association of these polymorphisms with growth traits. 122 Barki lambs were phenotyped for various growth traits, viz., birth weight (BW), weaning weight (WW), pre-weaning daily gain in weight (ADG1), post-weaning daily gain in weight (ADG2) and marketing bodyweight (MW). The polymerase chain reaction - single-strand conformational polymorphisms (PCR-SSCP) and DNA sequencing methods were used to identify the genetic variants in the FOXP3 gene. The associations between the variation in FOXP3 gene and growth traits were tested using a general linear model. Two variants (F1 and F2 with gene frequencies of 0.64 and 0.36, respectively), and three genotypes (F1F1, F1F2 and F2F2 with frequencies of 0.37, 0.53 and 0.10, respectively) were detected. The association of FOXP3 genotype was significant (p < 0.05) with ADG2 and MW. It is concluded that FOXP3 genotype might be helpful for sheep breeders to produce fast-growing lambs. However, further studies are needed in a large population to confirm the association we found.

Transcriptome profiling reveals differential gene expression in the rumen of Hu lambs at different developmental stages.

The development of the rumen is a critical physiological challenge in newborn ruminants. However, the molecular mechanism underlying different stages of rumen development in sheep remains poorly understood. Here, RNA sequencing and bioinformatics analysis were performed to compare the transcription profiles of rumen development at 7, 28 and 56 days of birth (D7, D28 and D56). We identified 1246, 2257 and 627 differentially expressed genes (DEGs) between D7 and D28, between D7 and D56, between D28 and D56, respectively. Also, 70 DGEs were co-expressed at these three time points. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses indicated most DEGs mainly related to transporter activity, channel activity and metabolism pathways. Noteworthy, the expression levels of most genes (CA4, CA9, CA12 and CA14) in nitrogen metabolic pathways were negatively correlated with the papilla length and width, but the papilla length and width were positively correlated with the expression of genes (PLA2G3, SLC26A9, SLC34A3) in ion transport pathway, suggesting that these genes may be involved in nitrogen metabolic and ion transport pathway and thus affect rumen development. These results provide new insight into the changes in RNA expression at different time points of rumen development in Hu sheep.

Practices and opinions of New Zealand sheep farmers towards pain management in lambs during castration and/or tail docking.

AIMS: To collect baseline data from New Zealand sheep farmers on techniques for docking and castrating lambs, their perceptions of the level of pain lambs experience following these procedures, and their opinions about the use of pain relief. METHODS: From a voluntary cross-sectional survey of New Zealand sheep farmers, descriptive statistics were provided for quantitative study variables. Thematic analysis was performed on the free-text comments. Univariable logistic regression was used to assess factors associated with farmers indicating they would consider using a device allowing administration of pain relief simultaneously with castration and tail docking. RESULTS: There were 432 survey responses containing sufficiently complete data for analysis. Of the 340 individuals (77.5%) always or sometimes performing castration of ram lambs, 242 (72.2%) used rubber rings for complete castration, 23 (6.9%) used the short scrotum method for cryptorchid castration, and 75 (22.4%) used a combination of both methods. Of the 423 individuals (97.9%) who indicated that they always or sometimes performed tail docking, 245 (57.9%) used a hot iron only, 148 (35.0%) used a rubber ring only, 26 (5.8%) used both methods, 3 (0.7%) used a surgical knife, and 1 (0.2%) provided no response. Less than 2% of respondents always or sometimes used pain relief for these procedures. Of the 432 respondents, 139 (32.2%) and 180 (41.7%) strongly agreed that castration and tail docking do not cause sufficient pain to warrant using pain relief, respectively. Time and cost were identified as major barriers to providing pain relief. In the unadjusted logistic regression analyses, respondents who were female, had high levels of education, had been farming < 20 years, who believed lambs experienced high levels of pain following the procedures, and who believed pain lasted longer than 6 hours, were more likely to indicate willingness to use pain control devices. CONCLUSION AND CLINICAL RELEVANCE: Our results suggest very few New Zealand sheep farmers currently provide lambs with pain relief following tail docking or castration. This is likely due to the perception that the procedures are not painful enough to warrant pain relief, and concern over time and cost. This highlights the need to educate farmers about lamb pain and distress following tail docking and castration, and its negative impact on animal welfare. Farmers also need pain relief techniques and tools that can be administered simultaneously with these procedures to save time and labour cost.

Effects of physical forms of a high grain-based diet on fattening performance, ruminal health, feeding behaviour, nutrient digestibility and carcass traits of finishing Lohi lambs.

This study aimed to evaluate the influence of different physical forms of complete diets on performance, feeding behaviour, digestibility, ruminal health, blood and carcass indices in fattening lambs. A randomised complete block design was used to assign thirty male Lohi lambs (300 ± 15 d old) with an initial body weight of 33 ± 1.4 kg in ten replications to one of three physical forms of the diet. For different treatments, the dietary ingredients were ground and mixed as (I) ground conventional mash (CM), (II) whole corn grains were mixed with the remaining pelleted ingredients as a texturised diet (TX), and (III) whole corn grains and the remaining ingredients were mixed as an unprocessed diet (UP). During the 60-d growth trial and 7-d digestibility experiment, individually housed lambs were fed ad libitum. Feeding diet UP improved (p < 0.05) dry matter intake, average daily gain and feed-to-gain ratio of fattening lambs. The ruminal pH tended to be lower in group TX compared with the other groups. The incidence of loose faeces consistency was 3.5 times higher (p < 0.05) in group TX compared to group UP. The daily intakes of dry matter (DM) and neutral detergent fibre (NDF), the rumination time and chewing activities were highest (p < 0.05) for lambs fed on the UP diet. The digestibility of DM, NDF and ether extract were greater (p < 0.05) for diet UP as compared to diet TX. The chilled and hot carcass weights were highest (p < 0.05) for group UP. The papillae density tended to be greater for group UP. However, blood metabolites, intestinal morphology, carcass marbling, tenderness, meat pH, cooking loss, and meat composition were similar across the treatments. It can be concluded that the unprocessed diet based on whole corn grain and soybean hulls improved growth performance, feeding behaviour and carcass yield through better nutrient utilisation and a stable ruminal environment.

Improving the productive performance of growing lambs using prebiotic and probiotic as growth promoters.

The feed additives (prebiotics and probiotics) are used to stabilize the healthy gut microbiome by supporting beneficial microorganisms, thereby improving the animal growth rate. Thirty growing lambs, with around 20.50 ± 0.65 kg live weight were placed into five equal groups (6 animals each). The concentrate feed mixture (CFM) + roughage was given to the control groups. The treatments (T) of T1, T2, and T3 treatments were fed the control ration with three levels of prebiotic supplementation: 0.50, 1.00, and 1.50 g/kg CFM of mannan oligosaccharids + beta glucan, respectively. The T4 received the control ration and was supplemented with 1.0 g/kg CFM probiotic (3.0 × 108 CFU/g, Bacillus amyloliquefaciens). The roughage was provided ad libitum, and the animals were supplemented with CFM at 2.00% of the body weight. A digestibility trial was conducted at the end of the 150-day feeding trial. The results demonstrated that increasing the prebiotic to 0.15% enhanced average daily gain and feed efficiency (P < 0.05) when compared to the control group. Although daily gain and feed efficiency in probiotic-fed animals were higher (P < 0.05) than in the control group, they were lower in prebiotic-fed lambs. The blood parameters were within normal range. The animals that received 0.10% prebiotic had the highest economic feed efficiency when compared to the other groups. Prebiotic treatment improved nutrient digestibility and nutritive values; however, the results for control and probiotic treatment were practically identical. Additionally, further research is needed to investigate the effects of prebiotics, probiotics and synbiotics as feed additives on productive and reproductive performance in ruminants.