Intensive Feeding System Research Articles

Multiomics of yaks reveals significant contribution of microbiome into host metabolism

An intensive feeding system might improve the production cycle of yaks. However, how intensive feeding system contributes to yak growth is unclear. Here, multi-omics, including rumen metagenomics, rumen and plasma metabolomics, were performed to classify the regulatory mechanisms of intensive feeding system on yaks. Increased growth performance were observed. Rumen metagenomics revealed that Clostridium, Methanobrevibacter, Piromyces and Anaeromyces increased in the intensively fed yaks, contributing to amino acid and carbohydrate metabolism. The grazing yaks had more cellulolytic microbes. These microbiomes were correlated with the pathways of “Alanine aspartate and glutamate metabolism” and “Pyruvate metabolism”. Intensive feeding increased methane degradation functions, while grazing yaks had higher methyl metabolites associated with methane production. These rumen microbiomes and their metabolites resulted in changes in plasma metabolome, finally influencing yaks’ growth. Thus, an intensive feeding system altered the rumen microbiome and metabolism as well as host metabolism, resulting in improvements of yak growth.

Effects of dietary supplementation with Acaciamearnsii tannin extract on carcass characteristics and meat quality of lambs

BackgroundPlant extracts are used as possible methane mitigants and to replace antibiotic feed supplements previously used prophylactically to improve the adaptation of lambs in intensive feeding systems. This study investigated the effects of Acacia mearnsii tannin extract used as anti-methanogenic feed additives on carcass and meat quality of lambs.MethodsForty Dohne Merino lambs, with an initial mass between 23.90 kg and 37.40 kg, were first stratified according to their initial body weight and thereafter one of the eight lambs with similar body weight were randomly assigned to four treatment groups (n = 10 lambs/treatment). The lambs were fed ad libitum with a basal total mixed ration. Four experimental diets were formulated: TMR diet (control); TMR diet with Rumensin® at a dosage of 75 mg/kg of DM feed (Monensin; Positive control); TMR diet with raw condensed Acacia tannin at 20 g/kg of DM feed (Crude tannin); TMR with addition of encapsulated condensed Acacia tannin at 20 g/kg of DM feed (Encapsulated condensed tannins). The lambs were slaughtered at a live mass of about 50 kg after a 19 week trial period.ResultsDietary tannin additives did not affect the carcass composition or colour aspects of lamb meat. However, there were minor changes in fatty acid profiles, particularly in the intramuscular adipose tissue. The addition of encapsulated tannin extract resulted in a higher proportion of C18:2n6t (0.15% ± 0.03 vs. 0.19% ± 0.03; p < 0.05), C18.3n3 (0.24% ± 0.04 vs. 0.29% ± 0.04; p < 0.05), C22:6n3 (0.02 ± 0.01 vs. 0.05 ± 0.03; p < 0.05), in comparison to monensin. This improvement in fatty acid profiles is presumably beneficial for human health, but it could affect the sensory quality of meat.ConclusionOur results suggest that Acacia mearnsii tannin extracts can be included as anti-methanogenic feed additives in lamb diets without compromising product quality.

Performances of upgraded Dwarf-Fayoumi chicken genotype in different feeding systems under smallholder farm management

The experiment was conducted to evaluate the performance of upgraded Dwarf-Fayoumi genotype (IDC♂ × Fay♀) with three different feeding regimes from onset of lay to 72 weeks of age. A total of 90 IDC♂ × Fay♀ birds of third generation (F3) at 16 weeks of age were distributed to 15 selected farmers nearby three villages of Bangladesh Agricultural University, Mymensingh. The villages were Kewatkhali, Boyra and Sutiakhali that selected for intensive, semi-scavenging and scavenging feeding systems, respectively. Each farmer was also given 5 pullets and 1 cockerel. The birds of full feeding and semi-scavenging system were given 76 g and 38 g mash feed per day, respectively. Pullets of semi-scavenging condition were allowed to scavenge in the farmer homesteads. The birds under scavenging condition reared without supplementation and were allowed to scavenge all day long. Result showed a significant difference (p&lt;0.05) among the feeding systems (intensive, semi-scavenging and scavenging) in production and reproduction traits, where intensive full feeding system exerted better performances. However, performance efficiency index (52.24), egg-feed price ratio (2.81) and return over feed cost (4.48) were found to be significantly higher (p&lt;0.001) in semi-scavenging feeding system. The egg weight (p&lt;0.01), breaking strength (p&lt;0.01) and dry yolk weights (p&lt;0.05) were significantly lower in the birds reared under scavenging feeding system, however, these traits were found statistically similar in the birds of intensive and semi-scavenging feeding system. Feeding systems had no impact on survivability of the experimental birds. Taking altogether, it could be concluded that IDC♂ × Fay♀ upgraded chicken under semi-scavenging system performed better than intensive and scavenging system under smallholder farm management. Bangladesh Journal of Animal Science 53 (1): 13-22, 2024

A multi-omic assessment of the mechanisms of intestinal microbes used to treat diarrhea in early-weaned lambs.

Transplant of donor microbiota can significantly alter the structure of the host's intestinal microbiota and alleviate early weaning stress. Screening for alternative-resistant products by transplanting fecal bacteria from healthy lambs is a current research trend in the livestock industry. In the present study, fecal microbiota transplantation was performed in lambs with diarrhea during early weaning. The transplanted fecal microbiota greatly reduced the diarrhea and serum inflammatory factor levels caused by early weaning. Transcriptome sequencing revealed that fecal microbiota transplantation alleviated colonic inflammation and increased the expression of colonic ion transport proteins. In addition, the levels of Streptococcus, Enterococcus, and Escherichia Shigella decreased in the jejunum, cecum, and colon of the lambs; meanwhile, the levels of Bifidobacterium and multiple secondary bile acids, such as ursodeoxycholic acid, increased in the colon. Furthermore, the abundance of Bifidobacterium was significantly negatively correlated with the diarrhea index. The fecal microbiota transplantation reshaped the intestinal microbiota of early-weaned lambs, protected the intestinal physiology and immune barrier, and reduced weaning stress. In addition to making available bacteriological products for controlling intestinal inflammation in young lambs, this study offers a theoretical framework and technical system for the mechanisms by which microbiota transplantation regulates intestinal health in young lambs.IMPORTANCEBefore weaning, the digestive system of lambs is not well developed; hence, its resistance to infectious diseases is weak. Under intensive feeding systems, lambs can easily be stressed and the risk of bacterial infection is high, which causes diarrhea, which in turn may cause mortality and significant economic losses to the livestock industry. With the elimination of antibiotics in animal feed, the incidence of mortality due to intestinal illnesses in lambs has gradually increased. There are several types of probiotics routinely used in young animals, but the effects and processes of their usage have only been assessed in monogastric animals. The lack of data on ruminants, particularly sheep, has severely hampered the process of efficient and healthy sheep breeding. Therefore, there is an urgent need to identify effective and safe functional supplements for lambs.

Seasonal Variation in Raw Milk VOC Profile within Intensive Feeding Systems.

The study aimed to assess the seasonal variation in raw milk volatile organic compounds (VOCs) from three indoor feeding systems based on maize silage (n = 31), silages/hay (n = 19) or hay (n = 16). After headspace solid-phase microextraction (HS-SPME), VOC profiles were determined by gas chromatography (GC). Chemical and VOC (log10 transformations of the peak areas) data were submitted to a two-way ANOVA to assess the feeding system (FS) and season (S) effects; an interactive principal component analysis (iPCA) was also performed. The interaction FS × S was never significant. The FS showed the highest (p < 0.05) protein and casein content for hay-milk samples, while it did not affect any VOCs. Winter milk had higher (p < 0.05) proportions of protein, casein, fat and some carboxylic acids, while summer milk was higher (p < 0.05) in urea and 2-pentanol and methyl aldehydes. The iPCA confirmed a seasonal spatial separation. Carboxylic acids might generate from incomplete esterification in the mammary gland and/or milk lipolytic activity, while aldehydes seemed to be correlated with endogenous lipid or amino acid oxidation and/or feed transfer. The outcomes suggested that VOCs could be an operative support to trace raw milk for further mild processing.

Seroprevalence and risk factors assessment of Brucella spp. in dairy buffaloes in mainland Greece.

Brucellosis is an infectious bacterial disease caused by members of genus Brucella, affecting both animals and humans, and resulting in both serious economic losses in animal production sector and deterioration of public health. A cross-sectional study was conducted from January to August of 2018 to determine the seroprevalence and associated risk factors of bovine brucellosis, in Central Macedonia and East Macedonia and Thrace, in mainland Greece. A total of 1,255 blood samples were collected using a simple random sampling technique from dairy buffaloes older than12 months. All serum samples were analyzed with Rose Bengal Test for screening and Complement Fixation Test for confirmation of the positive samples. Accordingly, the overall individual-level seroprevalence of dairy buffaloes in the study area was 0.72% (9/1,255, 95% CI:0.32-1.36%) while the overall herd-level seroprevalence was 15.38% (4/26, 95% CI:6.15-33.53%). Moreover, information was gathered on demographic characteristics of the owners, individual animals and herd level risk factors and other farm characteristics using a questionnaire. Higher prevalence of Brucella spp. was observed in buffaloes bred under intensive and semi-intensive feeding systems, compared to those bred under extensive ones. High seroprevalence of brucellosis was also observed in medium size herds. Two of the herds had recorded history of the disease, the last five years while, in these two herds delays in the implementation of brucellosis eradication programs were revealed. The present study indicated that the occurrence of brucellosis in Greece dairy buffalo farms is at a low magnitude. Even though the seroprevalence is low, it can still be potential hazard for both susceptible animals and humans

Genetic Variation in the Calpastatin Gene and its Association with Growth Traits in Batur Sheep

The present study aimed to investigate the association of the CAST genotype and growth traits in Batur sheep. Batur lambs were reared under an intensive feeding system. Bodyweight is measured monthly after weaning until six months of age. Blood representing thirty head were collected, genomic DNA was extracted as samples, and then 200 µl of whole blood samples were used. Specific primers were designed to amplify the CAST gene, samples were sequenced, then the researchers used the BioEdit program to identify any mutation. Calculation of genotypes, gene and allele frequencies, heterozygosities, and Chi-square test was performed. The analysis revealed a total of sixteen polymorphic sites in the CAST coding region. There are four alleles observed (A, G, C, and T), trans-versions at c.92T&lt;G and c.285G&gt;T loci, and transitions at c.214G&gt;A, c.280G&gt;A, c.301C&lt;T, and c.371A&gt;G. One individual disrupted the reading frame in the whole CAST sequenced. The genotype frequency analysis showed the highest predominance of the (TT, GG, CC, and AA) genotypes with frequencies (66.7 %, 62.9 %, 59.3 %, 66.7 %, and 55.6 %) as homozygous. In contrast, the heterozygous (TG, GA, GT, CT, and AG) genotypes were present at lower frequencies (29.6 %, 33.3 %, 37 %, 29.6 %, and 37 %), respectively with four difference alleles (T, G, C, and A). Post-weaning bodyweight till 6-month age of Batur sheep for the heterozygous genotypes at loci (c.92T&lt;G, c.214G&gt;A, c.280G&gt;A, and c.301C&lt;T) was slightly more massive than those carrying homozygous wild-type genotypes (c.285G&gt;T and c.371A&gt;G) with no significant differences (p &gt; 0.5). The lambs with the heterozygous genotype had a significantly higher muscle percentage as a whole, compared to the other genotypes. Polymorphic sites were present in Batur sheep for the first time about the association with the CAST gene. However, the CAST gene might not be a useful marker for developing future selection programs in Batur sheep unless further investigation of the CAST gene and its interactions with other genes involving muscle growth and carcass traits are analyzed through association studies at a large scale.&#x0D; Keywords: genetic variation, CAST gene, association, Batur sheep, growth traits

Effects of breed and fattening system on fatty acid and chemical composition of meat from male lambs

The purpose of this study was to examine the fatty acid and chemical composition of the Longissimus dorsi (LD) from male Tuj and Hemşin lambs reared in extensive, semi-intensive and intensive feeding systems. At the end of 90 days eight lambs from each breed and feeding system were slaughtered to determine chemical composition, and six lambs in each group were selected at random to assess fatty acid composition. Breed and feeding system interaction affected the quantities of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), and polyunsaturated fatty acids (PUFA), and the atherogenic (AI), thrombogenic (TI), and nutritive value (NVI) indices. In Hemşin the ratio of PUFA to SFA was higher in lambs fed in the extensive system than those produced in the semi-intensive and intensive systems, which were similar, whereas in Tuj this ratio decreased from the extensive to semi-intensive to intensive feeding systems. The ratio of omega n-6 to omega n-3 fatty acids was lower in the extensive and semi-intensive systems than it was in intensively fed Hemşin lambs, but increased with the intensity of feeding in Tuj lambs. Intramuscular fat content was higher in Hemşin lambs than in Tuj lambs and increased with the intensity of the feeding system. Conjugated linoleic acid content (CLA) was affected by feeding system in Hemşin lambs, but not in Tuj lambs. Because of their high PUFA/SFA ratio and low TI value, Tuj lambs reared in extensive feeding system were deemed to have the best performance.

Subacute ruminal acidosis in dairy herds: Microbiological and nutritional causes, consequences, and prevention strategies.

Dairy cattle are frequently fed high-concentrate (HC) diets in modern intensive feeding systems, especially in the transition period. During this period, cows face many alterations that include hormonal changes and shifting to a lactating state. Switching to a HC diet that may disrupt the ruminal microbiota balance can lead to subacute ruminal acidosis (SARA). Moreover, the main factor shaping the rumen microbiota is dietary composition, especially the ratio of starch to fibrous carbohydrates. Feeding highly fermentable carbohydrate diets after adaptation to forage diets leads to a rumen fermentation rate that exceeds rumen absorption and buffering rates, resulting in a reduction in ruminal pH. As a result of Gram-negative bacterial cell lysis, an increase in harmful ruminal bacterial metabolites, including lipopolysaccharide, lactic acid, and histamine, is observed. The interactions between the host immune system and the ruminal microbiota play an essential role in many physiological processes and the development of the disorder. Progress in DNA sequencing and bioinformatics platforms provides new opportunities to investigate the composition of ruminal microbes and yields unique advances in understanding ecology of the rumen. Subacute ruminal acidosis is linked with a change in the ruminal microbiota structure and richness and with other metabolic disorders; such as rumenitis, milk fat depression, laminitis, and liver abscesses. Therefore, this review aims to explore a better understanding of the crosstalk between diet and microbiota in the prevalence of rumen acidosis and its consequences, which is crucial for control strategies such as feeding management, and supplementation with thiamine, prebiotics, and probiotics.

Comparison and analysis on sheep meat quality and flavor under pasture-based fattening contrast to intensive pasture-based feeding system

ObjectiveThe objective of this study was to investigate the effect of 4-month intensive feeding on the meat quality, fatty acid profile, flavor, and growth performance of grazing Hulunbuir sheep (HBS).MethodsThe HBS were selected 4-months after birth in a pasture rearing system as the experimental animals (n = 44, female, average body weight 23.8±2.2 kg) then divided equally into pasture-based grazing fattening (PAS) and concentrate-included intensive fattening (CON) groups for another 4-month finishing. When finished fattening, all animals were slaughtered to collect musculus longissimus dorsi subcutaneous adipose tissue and to investigate the influences on meat quality, fatty acid profile, flavor and growth performance.ResultsThe results showed lambs in CON group got significantly higher live weight, hot carcass weight, and dressing percentage. The CON group had significantly higher value of redness (a*), lightness (L*) and water holding capacity (p<0.05), significantly lower value of Warner-Bratzler shear force than the PAS group (p<0.05). The subcutaneous fat from CON group lambs demonstrated a significantly higher content of C18:1 and C18:2 (p<0.05), but lower C14:0 and C16:0, indicating an increased degree of unsaturated fatty acid. The content of 4-methyloctanoic acid, 4-ethyloctanoic acid and 4-methylnonanoic acid had increased 2 to 4 times, representing a more intense odor in the CON group. However, the values were still lower than most sheep breeds reported, indicating the indoor feeding system could not fundamentally deteriorate the excellent meat characteristic of HBS.ConclusionIt was evident that lambs in CON group exhibited a better meat production performance, improved in meat color, texture and healthier fatty acid profile through pasture-weaned concentrate included intensive fattening system, which offers a good alternative regimen for lamb finishing and has a wide prospection in the HBS meat industry.

Effects of Donkeys Rearing System on Performance Indices, Carcass, and Meat Quality.

This study compared growth rates, carcass, and meat quality obtained from 24 male crossbred donkey foals reared for meat production under an intensive (I) or extensive (E) feeding system. Donkeys were slaughtered at 16 months of age; the average final body weight, hot and cold carcass weight, and hot and cold dressing percentage were significantly higher (p < 0.05) in the I group. Samples of Longissimus Thoracis et Lumborum (LTL) were taken from each foal for chemical and physical analysis. Group I showed significant (p < 0.05) higher intramuscular fat, while the E group showed significantly (p < 0.05) higher protein and unsaturated fatty acids (UFA) contents, including n-3 essential fatty acids. Saturated fatty acids (SFA) and glycogen were significantly higher (p < 0.05) in the intensive system, monounsaturated fatty acids (MUFA) were significantly higher in the extensive system. The ratio PUFA/SFA was significantly higher (p < 0.05) in group E. The Thrombogenic Index (TI) was significantly higher (p < 0.05) in the I group. Meat tenderness was significantly higher (p < 0.05) in group I. The feeding system had no effect on cholesterol content and meat color characteristics. Donkeys average daily gain, carcass weight, and some meat quality parameters were significantly affected by the rearing system.

Effects of total mixed ration with various silage on growth performance, serum parameters, ruminal fermentation, and bacteria community profile in beef cattle.

The possibilities of using high‐quality forages in incorporation with total mixed ration (TMR) during the fattening period of beef cattle have been investigated. A total of 30 Simmental bulls (438.94 ± 11.45 kg) were selected and randomly divided into two groups, TMR with single corn silage (SS) and TMR with various silage (MS). The whole experiment consisted of 15 days preparation period and 69 days experimental period. Rumen fluid and blood samples were taken from six beef cattle per treatment at the end of the experiment. The results showed that the average daily gain of the MS group (1.56 kg/day) was higher than (p < .05) the SS group (1.30 kg/day), and a decrease of feed conversion ratio in the MS (10.83) group was observed compared with SS group (12.36) (p < .05). The concentration of total volatile fatty acids for MS group was greater than (p < .05) the SS group. The activities of total antioxidant capacity and superoxide dismutase from MS group were also higher than the SS group, but lower urea nitrogen was found in the MS group from serum (p < .05). In addition, the abundances of the Prevotella‐1 and Verrucomicrobia were higher in the MS group than the SS group (p < .05). An increase in the flavonoid biosynthesis was detected in the MS group compared with the SS group by Kyoto Encyclopaedia of Genes and Genomes analysis. The present findings suggest that it is economical and healthy to substitute high‐quality forage +low level of concentrate for a relatively low proportion forage +high level of concentrate in a finishing diet of beef cattle, which was a feasible and healthy strategy in the intensive feeding system.

Intramuscular Fatty Acids in Meat Could Predict Enteric Methane Production by Fattening Lambs.

Simple SummaryThe rearing of ruminant animals is an environmental issue related to greenhouse gas emissions, mainly methane. In the current study, a regression analysis was carried out to obtain a regression equation able to successfully estimate methane production of lambs fattened under intensive feeding systems from their meat fatty acid profile and average body weight during the fattening period. The optimized model exhibited high precision, accuracy and reproducibility. It showed a clear relationship between methane emissions and the fatty acid profile of lamb meat. Our predictive model indicates that fatty acid contents in intramuscular fat could be used to establish the environmental footprint of meat from ruminants.Methane (CH4) emissions pose a serious problem for the environmental sustainability of ruminant production. The aim of the present study was to explore the usefulness of the intramuscular fatty acid (FA) profile to estimate CH4 production of lambs fattened under intensive feeding systems. A statistical regression analysis of intramuscular FA derived from ruminal metabolism was carried out to assess the best predictive model of CH4 production (g/d) in lambs fed with different diets. CH4 was calculated with three distinct equations based on organic matter digestibility (OMD) at maintenance feeding levels. The OMD of the experimental diets was determined in an in vivo digestibility trial by means of the indicator method. Regression models were obtained by stepwise regression analysis. The three optimized models showed high adjusted coefficients of determination (R2adj = 0.74–0.93) and concordance correlation coefficients (CCC = 0.89–0.98), as well as small root mean square prediction errors (RMSPE = 0.29–0.40 g/d). The best single predictor was vaccenic acid (trans-11 C18:1), a bioactive FA that is formed in the rumen to a different extent depending on dietary composition. Based on our data and further published lamb research, we propose a novel regression model for CH4 production with excellent outcomes: CH4 (g/d) = −1.98 (±1.284)–0.87 (±0.231) × trans-11 C18:1 + 0.79 (±0.045) × BW (R2adj = 0.97; RMSPE = 0.76 g/d; CCC = 0.98). In conclusion, these results indicate that specific intramuscular FA and average BW during fattening could be useful to predict CH4 production of lambs fed high concentrate diets.

Avaliação de sistemas de produção e análise econômica de cabritos lactentes criados na região semiárida da Paraíba

The objective of this study was to evaluate the performance and economic indicators of baby goats region submitted to different feeding systems in the Semiarid. A total of 30 baby goats of breed Parda Alpina × without defined racial pattern (SPRD) with initial weight of 3.35 kg ± 0.65 kg and final weight of 12.3 kg ± 0.5 kg were used, distributed in a completely randomized design in three breastfeeding systems with ten replicates each: traditional system (with natural breastfeeding), intensive breastfeeding system without concentrated supplementation, and intensive breastfeeding with concentrated supplementation. Goats submitted to the intensive artificial feeding system without concentrated supplementation showed a similar weight gain (121 g/day) when compared to the goats submitted to the system of suckling with concentrated supplementation (126 g/day). The highest income was provided by the animals submitted to the intensive system of suckling with concentrate. The gross margin for the two centenarians was positive, that is, revenues are higher than the effective operating cost, allowing us to conclude that the activity is paying off and will survive, at least in the short term. The diet of kids using concentrate provided better dry matter intake, greater weight gain and consequently presented better economic indicators.

Effect of pasture and intensive feeding systems on the carcass and meat quality of buffalo.

ObjectiveThis work was carried out to evaluate the effect of pasture (PA) feeding on buffalo meat quality compared with buffaloes reared intensively with the use of corn silage as a forage base or alternatively with polyphite meadow hay (PH).MethodsThirty Mediterranean bull buffaloes were distributed into three experimental diet groups: maize silage (MS), PH, and PA. The animals were slaughtered at a live weight of 250 kg, and carcass and meat quality were evaluated. After 7 days of ageing, physical and chemical parameters of longissimus thoracis muscle were determined. To evaluate lipid oxidation the thiobarbituric acid reactive substances was tested at 7 and 14 days, and also the fatty acid profile was recorded by gas chromatography.ResultsThe PA group, even if it showed carcass parameters lower than those of the silage maize group, reported a good meat percentage (60.59% vs 58.46%, respectively) and lower fat percentage (p<0.001). PA-fed animals showed meat redness, and even if only on raw meat, shear force was higher than the others. Low values of conjugate linoleic acid, polyunsaturated fatty acids, and n-3 were reported in the silage maize group. Principal component analysis (PCA) clearly showed the influence of different diets on meat quality, and PCA1 and PCA2 explained 82% of the variability.ConclusionBuffaloes reared on PA had meat with high nutritional value even if they showed poor carcass performance compared to the animals fed on MS. Buffaloes fed on polyphite hay were in an intermediate position, similar to grazing animals, according to the same nutritional determinations.

50 Sex ratio at birth in dairy cattle is affected by the invitro embryo production process

Data from a herd of 3,000 high-producing milking dairy cows under an intensive feeding system was analysed. The IVF laboratory at the farm uses a co-culture system (Vivanco-Mackie; page 30-48 in Proc. 2000 Australian Embryo Transfer Society) and transfers ∼1000 embryos per year. The semen used for IVF and for inseminations (AI) in the herd was female-sexed (F-sexed) and non-sexed (conventional). During the 4 years of evaluation (2016–2019) 1123 calves were born to AI with F-sexed semen and 6,456 to AI with conventional semen; the proportion of males born to AI with F-sexed semen was 9% (91% females), which was not different (P&amp;gt;0.05) from the expected ratio of 10% males and 90% females. The proportion of male calves born to AI with conventional semen was 53.2% (46.8% females), which agrees with the expected ratios for the population. During the same period of evaluation, 805 calves were born to IVF embryos transferred; 240 calves were born from embryos produced using F-sexed semen, of which 29.6% were males and 70.4% females, which was different (P&amp;lt;0.05) from the expected ratio of 10% males and 90% females. The proportion of male calves born from embryo transfer of IVF embryos produced with conventional semen was 82.7%, higher (P&amp;lt;0.05) than the expected 53.2% of males for the population; the proportion of females was 17.3%, significantly lower (P&amp;lt;0.05) than the expected 46.8% females for the population. For IVF, the proportion of males was significantly higher (P&amp;lt;0.05) than expected in all cases; for AI, there was no difference (P&amp;gt;0.05) between the observed sex proportion and the expected values. We conclude that the invitro embryo production process affects the sex ratio at birth in this population, and some factor in the IVF process is affecting the survival to calving of female embryos and consequently increasing the proportion of male calves born from invitro-produced embryos. Gutierrez et al. (2001 Reprod. Fertil. Dev. 13, 361–365) found a similar effect in dairy cattle and linked it to glucose imbalance in the media. Larson et al. (2001 PNAS 98, 9677-9682) found that female cattle embryos had a lower ability to progress in development in glucose-rich media, but the mechanism is not yet fully understood. Xu et al. (1992Mol. Reprod. Dev. 31, 249-252) and others indicate that invitro-produced male bovine embryos predominate among blastocysts, expanded and hatched stages. Meanwhile, embryos lagging in development are predominantly female. Kun Tan et al. (2016 Reproduction 151, 443-543) found that IVF in mice favours the birth of males because of dysregulated expression of representative dimorphic genes. Further studies in cattle are necessary to determine the cause of the increased proportion of males born from invitro embryos and to find ways to control it.

Carcass characteristics of Patanwadi ram lambs maintained under intensive feeding system

The present study was aimed to evaluate the carcass traits of Patanwadi ram lambs at 6.9 months (207 days; Gr-1) and 9.6 months (288 days; Gr-2) maintained under an intensive feeding system. The study involved 10 Patanwadi ram lambs maintained on Cenchrus ciliaris grass and supplemented 300 g concentrate daily. The lambs were slaughtered after fasting for 18 h to assess the carcass traits. The body length and live weights were significantly higher in Gr-2 lambs. Empty body weights, hot carcass weights, and dressing yields were significantly higher in Gr-2 than Gr-1. Loin eye area was significantly lower in Gr-1. In primal cuts, weights of the leg, loin, rack, neck and shoulder and breast, and foreshank were significantly different between the groups. The chilling losses were comparable among the groups. The lean yields did not differ significantly for Gr-1 and Gr-2. The subcutaneous fat was significantly higher in loin cut in Gr-2. The intermuscular fat contents were significantly lower for Gr-1. The dissected bone yields were comparable for Gr-1 and Gr-2. Lean: fat and meat: bone ratios were comparable. The present study indicated that Patanwadi ram lambs produce a desirable carcass with lean, fat and bone contents at 6-7 months of age with 30 kg body weight. Though carcass yield was higher at 9-10 months of age it-s not economical to rear ram lambs after 6 months because of poor growth rate and feed efficiency.

Significance of Feeding Practices for Small Ruminants: A Reveiw

Current study was carried in order to understand the significance of feeding practices for small ruminants. In this regards a detailed review of already conducted researches was performance, whereby obtained facts were found to be much interesting and valuable. It was indicated that the profitable small ruminants farming depends upon feeding practices because the feed cost about 70% in farming. Small ruminants are often offered grazing on summer and winter fodders for maintenance and production requirements. However, commercial production demands a change in feeding practice with a trend for more efficient utilization of scarce feed resources. It was further stated that goats spent more time on eating than sheep, while ruminating time remain higher in sheep than goats. Drinking time appears different among these species. Goats spent more time on playing and resting than sheep. Moreover, in extensive, semi-intensive and intensive feeding systems, dry matter intake was noticed higher in sheep than goats. Crude protein intake was reported significantly higher in sheep than goats fed intensively. NDF and ADF intake was higher in goats than sheep. Average daily weight gain was higher in sheep than goats on the extensive system followed by the semi-intensive system. Feed efficiency was similar in both species, while the cost of gain per kg was more economical in goats compared sheep. In conclusion both species performed better on extensive feeding system than the other systems. It might be because of natural grazing behavior.

Stall feeding of sheep and goats: An alternative system to traditional grazing on community lands

Sheep and goats in the country are mostly raised on grazing resources. But these resources are gradually shrinking over the periods both in term of areas under them and also in yield and quality. On the contrary, populations of sheep and goat are increasing rapidly to meet the demand of meat. This is resulting in overstocking and overcrowding on available grazing lands and sharp deterioration of grazing resources. The intensive system (stall feeding) as an alternative to traditional grazing and semi-intensive system, may be useful to maintain pace with growing meat demand in the changing scenario of grazing resources in the country. Studies have shown that lambs and kids on stall feeding with adequate nutrition and management attain faster growth, attain slaughter weights at an early age and produce heavier carcass weights, more dressing yield and desirable lean, fat and bone contents. Although initially intensive system seems costly due to more feed cost and more capital investment, but this is justified by higher economic returns to farmers. Therefore, it can be concluded that intensive feeding system for sheep and goats is better than extensive system and at par or better than semi-intensive system for lamb and kid fattening purpose from 3–6 months of age. This review article also discusses the possibility of economic viability of sheep and goats rearing under stall feeding.

Rangeland Grazing Strategies to Lower the Dependency on Imported Concentrates in Norwegian Sheep Meat Production

Norway has vast rangeland resources (292,361 km2) with an estimated carrying capacity of nearly four million sheep and lambs, twice the current number. However, the intensive production system currently applied has led to more concentrate dependency, resulting in heavier animals in addition to poorer utilization of rangelands and homegrown feed. Intensive feeding systems indirectly influence the sustainability of ecosystems by promoting intensive cropping that can deplete soil fertility and threaten landscape preservation and biodiversity. By contrast, extensive grazing systems can produce environmentally and animal-friendly food products and contribute to regulating soil health, water and nutrient cycling, soil carbon sequestration, and recreational environments. In this paper, the economics of current sheep feeding practices in Norway, using a linear programming model, were compared with more extensive systems which allow for higher usage of on-farm feed resources. Changes in current sheep farming practices have the potential to increase lamb meat production relative to mutton production, in addition to improving the year-round supply of fresh meat. The investigated alternatives, using the Norwegian White Sheep (NWS) breed, suggest that delayed lambing is useful only on farms with abundant pastures available for autumn feeding. Lambs achieve a better market price than hoggets and mature sheep. Therefore, based on the current Norwegian meat market and price offered per kilogram of meat for lamb, an increase in NWS lamb production improves farm profits. On the other hand, when the aim is on greater use of homegrown feed and rangelands, this can be achieved through hogget production, and the quantity of concentrates required can be reduced substantially.