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Goat population world-wide is increasing, and the dairy goat sector is developing accordingly. Although the new technology applied to the goat industry is being introduced slowly because the weight of traditional subsector in the dairy sector, considerable advances have been made in the last decade. Present review focuses on the emerging topics in the dairy goat sector. Research and development of traditional and new dairy goat products are reviewed, including the new research in the use of goat milk in infant formula. The research in alternatives to brine, production of skimmed goat cheeses and the use of different modified atmosphere packaging are also addressed. Special attention is given to antibiotic residues and their determination in goat milk. Functional foods for human benefits are a trending topic. Health properties recently discovered in dairy goat products are included in the paper, with special attention to the antioxidant activity. The dual-purpose use of goats by humankind is affecting the way of how new technology is being incorporated in the dairy goat sector and will certainly affect the future development of dairy goat products. [ABSTRACT FROM AUTHOR]

Cheese production has increased more than 3.5-fold since 1960, while animal rennet production has declined, thus other proteolytic enzymes have been developed. Cheese quality depend on many factors, some of them are linked to milk composition (genetic aspects: species, breed and animal, lactation stage and number, type of kidding, animal feeding and health, offspring season, etc.) and other due to cheesemaking aspects and storage processing (raw or pasteurized milk, coagulation enzymes and coagulation parameters (temperature and time), moulding, drainage, salting, ripening, smoking, etc.). All these factors interact and only under experimental conditions it is possible to analyse the effect of any particular feature by itself. Between all these factors, milk coagulation process is one of the most important steps for the cheese final characteristics. The differences in protein matrix degradation due the origin of coagulant agents affect cheese texture, odour, flavour and taste and consequently consumer's preference. This last assertion is especially important for the economic choices of the dairy firm. In the past, cheesemakers used animal rennet for curdling milk; it was produced by macerating the stomachs obtained from suckling ruminants according to the local uses, although plant coagulant was used in some typical specific cheesemaking processes. Nowadays, several types of coagulant are available, with different origin and variability in proteases for milk coagulation: animal origin rennet and vegetable coagulants than can be both artisan or commercial, microbial proteases and recombinant from genetically modified microorganism with cDNA for chymosin. In this paper the state of the art of these enzymes used in goat´s cheese industry is presented, also focused on artisan cheeses. Coagulant effect in physical-chemical and sensory profile of cheeses is analysed, also under an ethical and religious point of view. Finally, the importance of the market target in producing new cheese with vegetable coagulant is met, with an overview on the trends on cheese labelling issue. • The market for dairy products made with non-animal rennet is increasing. • Several types of coagulant are available, different for origin and proteases. • Effect of coagulant on cheese quality must be taken into account when planning dairy products with non-animal rennet. [ABSTRACT FROM AUTHOR]

Simple Summary: The progressive abandonment of local breeds dramatically threatens livestock biodiversity. The knowledge of these breeds should be broadened to understand their adaptive strategies, optimize their performance, promote their conservation, and thus contribute to ecological restoration. Investigating colostrum quality could be meaningful for understanding the nutritive concentration capacities and immunological status of females, and, as a consequence, for the future health status and growth of newborns. We hypothesize that the composition of goat colostrum is influenced by the breed and its typical farming system making colostrum from local breeds different from cosmopolitan ones. This study aimed to characterize colostrum quality, including basic chemical composition (i.e., fat, protein, lactose, and total solids) and immune variables (i.e., IgG, IgM, and lactoferrin) in three different local goat breeds from Northern Italy (i.e., Frisa Valtellinese, Orobica, and Lariana) and a cosmopolitan one (i.e., Camosciata delle Alpi) reared under traditional semi-extensive and intensive systems, respectively. Results showed variability in the colostrum quality among breeds, which could be linked to the different farming systems, processes of artificial and natural selection, and meat or dairy aptitude of the animals. However, local goats had a higher quality of colostrum that could confer greater hardiness and rusticity to their kids. This study aimed to characterize the colostrum quality in three different local goat breeds of Northern Italy (i.e., Frisa Valtellinese, Orobica, and Lariana) and a cosmopolitan one (i.e., Camosciata delle Alpi) (n = 30 per breed), reared under traditional semi-extensive and intensive systems, respectively. Lariana showed the highest percentage of fat (10.18 ± 3.14%) and total solids (30.73 ± 4.89%) but the lowest percentage of lactose (1.87 ± 0.82%; p < 0.05); Orobica had the lowest percentage of fat (7.13 ± 2.48%), total solids (24.11 ± 5.48%), and protein (10.77 ± 4.53%) but the highest percentage of lactose (3.16 ± 0.73%; p < 0.05). This suggests that breeds which have a more pronounced meat aptitude (i.e., Frisa and Lariana) have a higher concentration of components than breeds with more dairy aptitude (i.e., Orobica and Camosciata). Uni- and multivariate analyses showed that IgG is the parameter that best differentiates local breeds from cosmopolitan ones (p < 0.01). Colostrum from Frisa goats showed the highest IgG concentration (100.90 ± 8.11 mg/mL), while the lowest concentration was in the Camosciata breed (74.75 ± 20.16 mg/mL). Finally, the highest lactoferrin concentration was in Frisa (1781.3 ± 892.6 µg/mL) and the lowest in Camosciata and Lariana (763.1 ± 357.9 and 1148.0 ± 858.6 µg/mL, respectively; p < 0.05). Differences between Camosciata and local breeds could be due to the different farming systems, in addition to the genetic characteristics. The higher quality of colostrum produced by some local goats could be an adaptive characteristic that helps the growth and survival of the kids. [ABSTRACT FROM AUTHOR]

Colostrum intake is a key factor for newborn ruminant survival because the placenta does not allow the transfer of immune components. Therefore, newborn ruminants depend entirely on passive immunity transfer from the mother to the neonate, through the suckling of colostrum. Understanding the importance of specific colostrum proteins has gained significant attention in recent years. However, proteomics studies of sheep colostrum and their uptake in neonate lambs has not yet been presented. The aim of this study was to describe the proteomes of sheep colostrum and lamb blood plasma, using sodium dodecyl sulfate-PAGE for protein separation and in-gel digestion, followed by liquid chromatography-tandem mass spectrometry of resulting tryptic peptides for protein identification. An isobaric tag for relative and absolute quantitation (iTRAQ)-based proteomics approach was subsequently used to provide relative quantification of how neonatal plasma protein concentrations change as an effect of colostrum intake. The results of this study describe the presence of 70 proteins in the ovine colostrum proteome. Furthermore, colostrum intake resulted in an increase of 8 proteins with important immune functions in the blood plasma of lambs. Further proteomic studies will be necessary, particularly using the selected reaction monitoring approach, to describe in detail the role of specific colostrum proteins for immune transfer to the neonate. [ABSTRACT FROM AUTHOR]

Most suckling kids are raised on farms for cheese production, and many goat farmers rear kids with milk replacers. The aim of this work was to study the influence of the use of milk replacers on the color of four muscles. A total of 246 suckling kids of eight breeds were slaughtered to achieve carcasses of 5 kg. The color of the biceps femoris, semimembranosus, semitendinosus, and longissimus thoracis muscles was measured with a spectrophotometer, and CIELab coordinates were registered. In addition, the pH of longissimus thoracis was measured. The effect of the rearing system (RS) on the color of the studied muscles is strongly modulated by breed. In general terms, there are two groups of kids according to the color of meat. The first group has great lightness and hue angle including Malagueña, Palmera, and Tinerfeña fed natural and artificial milk. The second group with great redness includes Retinta, Payoya, and Verata fed natural and artificial milk together with Florida fed natural milk and Cabra del Guadarrama fed milk replacers. Hence, farms should consider selecting a breed and RS together. Most of the kid meat with high pH comes from kids raised on milk replacers. Because artificial RSs use very early weaning, which might induce a high pH and dark meat, two artificial rearing strategies can be proposed. The first strategy is to choose less sensitive breeds that produce meat with a normal pH. The second strategy is to restrict suckling of natural milk but minimize separation from the mother. [ABSTRACT FROM AUTHOR]

Most suckling kids are raised on farms oriented toward cheese production, and many goat farmers' rear kids with milk replacers. The aim of the current study was to investigate the consumer preferences for the visual appearance of meat from suckling kids reared with milk replacers or natural milk. Meat colour was the major criterion used to select meat. The meat of Cabra del Guadarrama reared with milk replacers was preferred by 72% of consumers and had a preferred lightness and hue angle. The rearing system did not influence preference through the time of display. Web-based surveys provided similar information to information recorded with live surveys using actual products instead of pictures. Meat colour appears to be a recurring intrinsic cue to assess consumer preference. In general, consumers preferred meat of light suckling kids reared on milk replacers because this meat had a high lightness and hue angle as well as a low chroma. Meat colour was the major criterion used to choose meat. Rearing system did not influence consumer's preference through time of display. Consumers preferred meat with high lightness and hue angle, and low chroma. [ABSTRACT FROM AUTHOR]

Muscle fibres have an important impact on meat quality. There are different types of skeletal muscle fibres, mainly oxidative and glycolytic. The present study showed that dairy breeds and goat kids raised with milk replacer had less oxidative fibres than meat breeds and goat kids raised with their dams. In addition, the muscle fibres measured in this study were smaller in dairy breeds and kids raised with milk replacer than in meat breeds and goat kids raised with the dams. [ABSTRACT FROM AUTHOR]

Background: Hot-iron disbudding is a common management procedure to prevent horn growth in calves. The study objective was to examine effect of age, breed and sex on horn bud size of dairy-bred and suckler-bred calves at time of disbudding. Results: The left and right horn bud size (diameter and height in mm) of 279 calves, including dairy-bred Holstein-Friesian (Male (M) = 88) and 191 suckler-bred (86 Charolais, CH; (M = 39, Female (F) = 47), 67 Limousin, LM; (M = 32, F = 35) and 38 Simmental, SI; (M = 22, F = 16) sired)) was measured using a digital calliper at time of disbudding. Calves were retrospectively assigned to two age categories at time of disbudding: 1), 14 to 28 days (d) old and 2), 29 to 60 d old. Holstein-Friesian M calves had a greater horn bud diameter (16.97 v.14.45 mm) and height (7.79 v. 5.00 mm) compared to suckler-bred M calves (P < 0.01), with no difference (P > 0.05) among the suckler-bred calves. Suckler-bred M calves had a greater horn bud diameter (14.46 vs 13.29 mm) and height (5.01 vs 3.88 mm) compared to suckler-bred F calves (P < 0.05). The slopes of the lines of best fit show that horn bud diameter and height increased with age (P < 0.05) for HF, SI male and CH female calves while there was no relationship with age (P > 0.05) for CH and LM male calves, or for SI and LM female calves. Linear regression of age with diameter and with height for each breed and sex showed high variability in the data as indicated by R-squared values ranging from 0.003-0.41 indicating that in the case of the diameter and the height, the weight of the fitting effect was poor. Conclusions: Calf age is not a good predictor of horn bud size and recommendations for the disbudding of calves should be based on horn bud size and not on age. The implications of these findings are that calves should be disbudded while horn development is still at the bud stage and when the bud is large enough to be easily palpable/visible, but not so large that disbudding could lead to severe tissue trauma. [ABSTRACT FROM AUTHOR]

Immature gilthead sea bream (Sparus aurataL.) with a mean initial weight of 25.6 g were reared over 11 months to market size under different photoperiods: 16L:8D; 24L:0D and a control. Differences in final mean weight were significant between the three treatments (P<0.001): 16L:8D, 465.0 g; 24L:0D, 445.9 g; control, 402.6 g. Fish from the 24L:0D consumed most while 16L:8D fish converted it most efficiently. The lipid content of fillets was lower (P<0.05) for the 24L:0D (5.37±0.16 g 100 g−1 of fillet) than for the control (6.02±0.12 g), and the moisture content lower for the control than for either treatment groups. Skin luminosity (L*) was directly related to the number of hours of light exposure. [ABSTRACT FROM AUTHOR]

Simple Summary: Goats are important species due to their contributions to the development of rural areas. Spain has one of the largest goat populations in Europe; however, literature on goat carcasses is very scarce and, therefore, it is crucial to study the specific productive potential of each breed. Previous studies by our team on other Spanish goat breeds have shown some interactions between breed and rearing systems and, consequently, further analysis is necessary. This paper aims to contribute to the general knowledge on the subject. Since goat milk has a higher value than kid meat in Europe, some farmers rear kids with milk replacers, although some studies have stated that kids raised on natural milk yield higher-quality carcasses. Our previous studies showed some interactions between breed and rearing system on carcass and meat quality. This study evaluated the influence of the use of milk replacers on several carcass characteristics of suckling kids from eight Spanish goat breeds (Florida, Cabra del Guadarrama, Majorera, Palmera, Payoya, Retinta, Tinerfeña, and Verata). A total of 246 kids fed milk replacer (MR) or natural milk (NM) were evaluated. Carcass, head, viscera, and kidney fat weights, as well as several carcass measurements (round perimeter, forelimb width, carcass length, forelimb length, and carcass compactness index), were registered. Forelimbs were dissected to study tissue composition. For all studied variables, interactions were found between rearing system and breed. In general, the MR rearing system increased the head and visceral weights, as well as the length measurements and muscle percentages. Conversely, the NM rearing system increased carcass compactness and resulted in higher fat contents, independent of the deposit. The choice of one or another rearing system should be made according to the needs of the target market. [ABSTRACT FROM AUTHOR]

Simple Summary: The milk production systems in goats are mainly intensive and semi-extensive. In the former, the goats are housed and are fed a total mixed ration with vitamin supplementation. In the latter, the feeding of the goats is based on grazing, although with some supplementation with compound feed. Retinol and α-tocopherol that appear in these animals come from the feeding regime, since the animal cannot synthesize them. The objective of this study was to verify if the vitamins provided in different management systems of Payoya lactating goats are good markers of the production system. For this purpose, the content of carotenoids, retinol and α-tocopherol in the milk and plasma of the goats was quantified. Results showed an inverse relationship of the amount of these vitamins between milk and plasma. On the other hand, the metabolism of different vitamins depends on their origin (natural/synthetic), with natural α-tocopherol and synthetic retinol showing the highest amount in milk. Finally, it was found that these compounds can be good traceability tools which allows to guaranty to the consumer the origin of the products derived from these animals. The retinol and α-tocopherol concentrations were quantified (μg/mL) using high-performance liquid chromatography (HPLC) in both plasma and milk of goats from three management systems. The aim was to investigate if the compounds pass from feed to animals' fluids and to evaluate their potential use as feeding regime biomarkers. A total of 45 Payoya dams were distributed in three groups according to management system during the first month of lactation: mountain grazing (MG), cultivated meadow (CM) and total mixed ration (TMR). TMR group had higher concentrations of retinol in both plasma (25.92 ± 3.61 at 30 days postpartum) and milk (8.26 ± 0.79 at 10 days postpartum), and they were also the unique animals whose milk contained detectable concentrations of α-tocopherol (3.15 ± 0.19 at parturition). However, MG and CM goats showed higher plasma concentrations of α-tocopherol (64.26 ± 14.56 and 44.65 ± 5.75 at 30 days postpartum, respectively). These results could imply differences in the bioavailability of supplemented vitamin A and natural β-carotene and between the natural/synthetic forms of α-tocopherol. An inverse relationship between the fluids (plasma/milk) in the contents of α-tocopherol and retinol was observed as lactation progressed. Since 80% of the animals were correctly classified using a discriminant analysis based on these vitamins, these compounds could be used as traceability biomarkers of feeding system, but further studies are necessary to know the possible passage to kid meat. [ABSTRACT FROM AUTHOR]

Background: Seasonal weight loss (SWL) is a very important limitation to the production of ruminants in the Mediterranean and Tropical regions. In these areas, long dry seasons lead to poor pastures with low nutritional value. During the dry season, ruminants, particularly those raised in extensive production systems, lose around 30% of their body weight. Seasonal weight loss has important consequences on animal productive performance and health. In this study, RNA sequencing was used to characterize feed restriction effects in dairy goat of 2 breeds with different SWL tolerance: Majorera (tolerant) and Palmera (susceptible). Nine Majorera and ten Palmera goats were randomly distributed in a control and a restricted group: Majorera Control (adequately fed; MC; n = 4), Palmera Control (adequately fed; PC; n = 6), Majorera Restricted (feed restricted; ME; n = 5) and Palmera Restricted (feed restricted; PE; n = 4). On day 22 of the trial, mammary gland biopsies were collected for transcriptomics analysis. Results: From these samples, 24,260 unique transcripts were identified. From those, 82 transcripts were differentially expressed between MC and ME, 99 between PC and PE, twelve between both control groups and twenty-nine between both restricted groups. Conclusions: Feed restriction affected several biochemical pathways in both breeds such as: carbohydrate and lipid transport; intracellular trafficking, RNA processing and signal transduction. This research also highlights the importance or involvement of the genes in tolerance (ENPP1, S-LZ, MT2A and GPNB) and susceptibility (GPD1, CTPS1, ELOVL6 and NR4A1) to SWL with respectively higher expression in the Majorera restriced group and the Palmera restricted group in comparison to the control groups. In addition, results from the study may be extrapolated to other dairy ruminant species. [ABSTRACT FROM AUTHOR]

The viability of conventional goat farms, such as the native Payoya dairy goat, could be improved by switching to organic production, but product quality needs to be ensured. The present work assesses the carcass and meat quality of Payoya kids raised under conventional and organic grazing-based systems. Twenty-four kids (12 males, 12 females) were selected from each system (n = 48). The slaughter live weight (8.52 vs. 8.28 kg), cold carcass weight (4.44 vs. 4.29 kg) and farm dressing percentage (51.7 vs. 50%) of the conventionally raised kids were significantly higher than those of the organic kids. The shoulder (first category) (21.7 vs. 22.3%) and long leg (32 vs. 32.9%) percentages were lower in the conventional than in the organic kids. The percentage contribution of the intermuscular fat (10.70 vs. 8.11%) to the shoulder weight was greater in the conventional kids, while the percentages of muscle (59.7 vs. 57.2%) and bone (24.7 vs. 22.8%) were higher in the organic kids. For the chemical composition, there were only differences between the two sexes in the percentage of fat (6.64 and 7.99% on dry matter, for male and female, respectively). For rheological variables, only differences were found in the water holding capacity (% water expelled), the meat of the organic females had a higher value (17%) than that of the conventional females (14%). For the meat colour, the conventional male kids returned the highest values for C* and Hº (14.32 and 64.34, respectively). Farms following conventional grazing-based management could easily switch to organic production. Most of the meat and carcass quality variables studied were very similar across the systems. [ABSTRACT FROM AUTHOR]

Several physiological and metabolic changes take place in dairy ruminants around parturition (late pregnancy, parturition, and early lactation). Dairy species are genetically selected for their higher milk production compared with non-dairy species. This fact causes a constant stress that impairs the immune status of the animal, with consequences for its welfare and performance. In the present study, we assessed the immune status of high-yield dairy sheep and goats by quantifying IgG and IgM concentrations, as well as chitotriosidase (ChT) and complement system [total complement system (TC) and alternative complement pathway (AC)] activity in blood plasma around parturition. We also measured IgG and IgM concentrations and ChT activity in colostrum and milk during the first 40 d postpartum. The lowest blood IgG concentration was at parturition in both species. We detected no differences in blood IgG concentrations between species. Blood IgM concentrations were constant in both species throughout the study period. However, blood IgM concentrations were greater in sheep than in goats. Blood ChT activity was greater in goats than in sheep, and both species showed constant activity of this enzyme throughout the study period. We observed no differences in complement system (TC and AC) activity between sheep and goats. In addition, both TC and AC activity were constant in both species throughout the experiment. In general, IgG and IgM concentrations were greater in sheep colostrum than in goat colostrum, but these differences disappeared after d 4 (IgG) and d 3 (IgM) postpartum. In both species, the highest IgG and IgM concentrations were measured in colostrum, gradually decreasing during the first days postpartum. Chitotriosidase activity decreased in both species from colostrum to milk, although goats always showed greater ChT activity than sheep. Both sheep and goats seemed to be more susceptible to infectious diseases around parturition. As well, goats showed greater ChT activity in blood, colostrum, and milk than sheep. This fact may give these animals additional protection against parasite and fungal infections. [ABSTRACT FROM AUTHOR]

Most of European Union goats are slaughtered with carcase weights between 5 kg and 11 kg. Some farmers rear kids with milk replacers to produce cheese with the dams' milk. The aim of this experiment was to study the volatile compounds (VOCs) of meat of suckling light kids reared with natural milk or milk replacers and to study the influence of consumers' psychographic characteristics on the sensory preference for meat. Gas chromatography-mass spectrometry was performed to identify the VOCs and consumers evaluated the flavour, juiciness and overall acceptability. Thirty-five VOCs were detected and 44.3%, 25.1%, 6.9% and 2.3%, were aldehydes, hydrocarbons, ketones and alcohols, respectively. The influence of the rearing system on VOCs clearly depended on the breed. The use of milk replacers did not affect the percentage of linear aldehydes compared to the use of natural milk. However, the major aldehyde, hexanal (34.8%), was related to the use of natural milk and correlated positively with both the flavour (r = 0.21) and overall acceptability (r = 0.24). On the other hand, hydrocarbons such as hexane were related to MR, and 2-methyl-pentane and 3-methyl pentane were correlated with the acceptability of flavour (r = −0.22 and −0.25, respectively) and with the overall acceptability (r = −0.21 and −0.24). The 2-penthyl furan and 2-ethyl-1-hexanol were correlated with the overall acceptability (r = −0.22 and −0.22, respectively). Therefore, the acceptability of meat from suckling kids fed natural milk was greater for older consumers and people with a moderate consumption of meat. Goat farmers remove the kids from their dams at a very young age and rear them with milk replacers, but this practice may alter the flavour of meat. The major aldehyde, hexanal, was related to the use of natural milk and correlated positively with the flavour and overall acceptability. Acceptability of meat from suckling kids fed natural milk was greater for older consumers and people with a moderate consumption of meat. [ABSTRACT FROM AUTHOR]

The number of organic farms is growing, but switching from conventional to organic production requires farms continue to produce high quality products. This study compares the carcase and meat quality of Blanca Andaluza goat suckling kids raised under organic and conventional grazing-based stock raising production systems. Twenty-four twin kids (12 males, 12 females) were selected from representative farms of each system. Body weight, dressing percentage, carcase linear measurements, non-carcase components, primary carcase and minor cuts, tissue composition, chemical composition and rheological variables, pH and colorimetric variables, were examined. No significant differences were seen between the production systems or sex with respect to most of the variables studied. However, some non-carcase components and colorimetric variables were affected, with the organic kids' meat returning lower values for lightness, yellow index, chroma and Hue angle. Indeed, some of the meat colour variables examined easily discriminated between the animals raised under the different production systems. These results show that conventional grazing–based farms raising these goats could easily turn to organic production without carcase or meat quality being affected. Organic farms are growing in number. The transformation to organic kid-raising is easy, with meat quality unaffected. These results are of interest with respect to the viability of conventional goat farms. [ABSTRACT FROM AUTHOR]

Seasonal weight loss (SWL), is a major limitation to animal production. In the Canary Islands, there are two dairy goat breeds with different levels of tolerance to SWL: Majorera (tolerant) and Palmera (susceptible). Our team has studied the response of these breeds to SWL using different Omics tools. The objective of this study was to integrate such results in a data driven approach and using dedicated tools, namely the DIABLO method. The outputs of our analysis mainly separate unrestricted from restricted goats. Metabolites behave as "hub" molecules, grouping interactions with several genes and proteins. Unrestricted goats upregulated protein synthesis, along with arginine catabolism and adipogenesis pathways, which are related with higher anabolic rates and a larger proportion of secretory tissue, in agreement with their higher milk production. Contrarily, restricted goats seemingly increased the synthesis of acetyl-CoA through serine and acetate conversion into pyruvate. This may have occurred to increase fatty acid synthesis and/or to use them as an energy source in detriment to glucose, which was more available in the diet of unrestricted goats. Lastly, restricted Palmera upregulated the expression of PEBP4 and GPD1 genes compared to all other groups, which might support their use as putative biomarkers for SWL susceptibility. Seasonal weight loss (SWL) is a major issue influencing animal production in the tropics and Mediterranean. By studying its impact on the mammary gland of tolerant and susceptible dairy goat breeds, using Omics, we aim at surveying the tissue for possible biomarkers that reflect these traits. In this study, data integration of three Omics (transcriptomics, proteomics and metabolomics) was performed using bioinformatic tools, to relate putative biomarkers and evaluate all three levels of information; in a novel approach. This information can enhance selection programs, lowering the impact of SWL on food production systems. [Display omitted] • Majorera and Palmera goats are resilient and susceptible to seasonal weight loss (SWL). • Multi-omics data integration can reveal and relate biomarkers of interest. • PEBP4 and GPD1 genes are possible indicators of SWL susceptibility. [ABSTRACT FROM AUTHOR]

Refractometry has been proposed as a farm technique to estimate the IgG concentration in colostrum. In order to validate the method in goat colostrum using a clinical refractometer, 216 colostrum and milk samples were obtained from 54 dairy goats. Samples were evaluated for protein concentration using a clinical refractometer and IgG concentration was measured using a commercial ELISA. The r2 for the linear regression between refractometry value and IgG concentration measured by ELISA was 0.79, and the area under the receiver operating characteristics curve was 0.99. The proposed cut-off value using the clinical refractometer was 10 mg/mL. At this point, the sensitivity, specificity, negative predictive value, positive predictive value, Youden's index and accuracy were 100%, 95.19%, 100%, 76.32%, 0.95% and 95.83%, respectively. [ABSTRACT FROM AUTHOR]

Abstract: BACKGROUND: The use of milk replacers to feed suckling kids could affect the shelf life and appearance of the meat. Leg chops were evaluated by consumers and the instrumental color was measured. A machine learning algorithm was used to relate them. The aim of this experiment was to study the shelf life of the meat of kids reared with dam's milk or milk replacers and to ascertain which illuminant and instrumental color variables are used by consumers as criteria to evaluate that visual appraisal. RESULTS: Meat from kids reared with milk replacers was more valuable and had a longer shelf life than meat from kids reared with natural milk. Consumers used the color of the whole surface of the leg chop to assess the appearance of meat. Lightness and hue angle were the prime cues used to evaluate the appearance of meat. CONCLUSION: Illuminant D65 was more useful for relating the visual appraisal with the instrumental color using a machine learning algorithm. The machine learning algorithms showed that the underlying rules used by consumers to evaluate the appearance of suckling kid meat are not at all linear and can be computationally schematized into a simple algorithm. © 2017 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The South American guinea pig rodent has become a livestock animal acceptable for human consumption in different parts of the world. Its white meat has a great potential as a new protein source, and its social and economic importance for different human populations is considered key for development. Scarce data are found in the literature when the statistical livestock information is checked, and few researches have been done about morphological characteristics of guinea pigs carcasses. These works do not follow the same procedures, using different criteria, overall the jointing, making it difficult to compare different studies. The aim of the present study is to suggest a practical and normalized method to analyse the guinea pig carcass characteristics allowing their evaluation. It describes the main traits to be considered from the birth of the animal to the carcass analysis. This work concerns: (1) growth, feeding, pre-slaughter and slaughter processing, (2) method for the definition, hanging and presentation of the carcass, (3) carcass morphological characteristics, (4) jointing procedure based on four anatomically defined regions, (5) methods for evaluating meat pH and colour and (6) method for tissue separation. This proposal could be useful to compare data of these animals under different conditions. [ABSTRACT FROM PUBLISHER]

Seasonal weight loss (SWL) is a significant limitation to animal production. Breeds that have evolved in harsh climates have acquired tolerance to SWL through selection. Herein, label free proteomics was used to characterize the effects of SWL in two goat breeds with different levels of adaptation to nutritional stress: Majorera (tolerant) and Palmera (susceptible). Nine Majorera and 10 Palmera dairy goats were used, divided in 4 sets, 2 for each breed: underfed and a control group: Majorera Control (MC), Palmera Control (PC), Majorera Restricted (ME) and Palmera Restricted (PE). At day 22, mammary gland biopsy samples were obtained. Label free proteomic analysis enabled the identification of over 1000 proteins, of which 96 showed differential expression between two of the groups within studied comparisons. Majorera breed showed higher expression of immune system related proteins. In contrast, Palmera breed showed higher expression of proteins related to apoptosis. Results indicate that the two goat breeds have a distinct metabolism reaction to SWL, and that proteins related to the immune system and apoptosis such as cadherin-13, collagen alpha-1, nidogen-2, clusterin and protein s100-A8 could be considered putative candidates as markers of tolerance to SWL. Biological significance Seasonal weight loss (SWL) is one of the major constraints to animal production in the tropics. We compared the proteomics profiles of two dairy goat breeds with different levels of tolerance to SWL under control and feed restriction conditions using label free proteomics. We have identified over 1000 proteins in the goat mammary gland, of which 96 showed differential expression. Despite the fact that both breeds showed a decrease in the number of proteins related to protein, carbohydrates and fat biosynthesis, the tolerant breed showed higher expression of immune system related proteins compared to the susceptible breed. On the contrary, the susceptible breed had higher expression of apoptosis related proteins indicating that both breeds reacted differently to weight loss and that proteins related to the immune system and apoptosis such as cadherin-13, collagen alpha 1, nidogen-2 or clusterin may be suggested as markers of tolerance to SWL. [ABSTRACT FROM AUTHOR]

Background: Colostrum intake by newborn lambs plays a fundamental role in the perinatal period, ensuring lamb survival. In this study, blood plasma samples from two groups of newborn lambs (Colostrum group and Delayed Colostrum group) at 2 and 14 h after birth were treated to reduce the content of high abundance proteins and analyzed using Two-Dimensional Differential in Gel Electrophoresis and MALDI MS/MS for protein identification in order to investigate low abundance proteins with immune function in newborn lambs. Results: The results showed that four proteins were increased in the blood plasma of lambs due to colostrum intake. These proteins have not been previously described as increased in blood plasma of newborn ruminants by colostrum intake. Moreover, these proteins have been described as having an immune function in other species, some of which were previously identified in colostrum and milk. Conclusions: In conclusion, colostrum intake modified the low abundance proteome profile of blood plasma from newborn lambs, increasing the concentration of apolipoprotein A-IV, plasminogen, serum amyloid A and fibrinogen, demonstrating that colostrum is essential, not only for the provision of immunoglobulins, but also because of increases in several low abundance proteins with immune function. [ABSTRACT FROM AUTHOR]

Abstract: To enhance the nutritional quality of meat, dietary strategies have been developed to manipulate the fatty acid profiles of muscle tissue. Fatty acids affect meat attributes, including hardness, colour and lipid stability, and flavour. Little research has been done, however, on the effects of dietary omega-3 polyunsaturated fatty acid (PUFA) supplementation on the sensory characteristics of meat. To address this issue, six diets were fed to goat kids: goat''s milk, powdered whole cow''s milk, powdered whole cow''s milk plus docosahexaenoic acid (DHA) (low dose), milk replacer, milk replacer plus DHA (low dose), and milk replacer plus DHA (high dose). A descriptive, semi-trained sensory evaluation and a consumer triangular test were performed to analyse the resulting meat. High doses of omega-3 PUFA produced meat with unusual odours, unpleasant flavours, and low overall appreciation scores. Low doses of DHA maintained a positive sensory perception. [Copyright &y& Elsevier]

Bird susceptibility to attacks by blood-sucking flying insects could be influenced by urogypial gland secretions. To determine the effect of these secretions on biting midges and black flies, we set up a series of tests. First, we placed uropygial gland secretions from blue tit Cyanistes caeruleus broods inside empty nest boxes while empty nest boxes without gland secretions were treated as controls. Blue tit broods, from which we had obtained uropygial secretions, were affected by biting midges and black flies. However, these insects were absent in nest boxes both with and without secretions from nestlings' uropygial glands. We subsequently tested for the effects of uropygial gland secretions from feral pigeons Columba livia monitoring the number of biting midges captured using miniature CDC traps. There was no significant difference in the number of biting midges captured. Overall, our results did not support a potential role of avian uropygial gland secretions in attracting biting midges and black flies. [ABSTRACT FROM AUTHOR]

Simple Summary: In Spain, goat farms are mainly oriented to milk production, although kid meat contributes to their sustainability, particularly in autochthonous breeds such as Payoya. Usually, kids are fed artificial milk until slaughter, allowing the use of goat milk for the commercialization of cheese, but several studies indicate that feeding kids natural milk improve the quality of their meat. The aim of the present study was to find traceability markers to discriminate between kids that are fed natural milk (with different goat management systems) and those fed a milk replacer. For this purpose, we proposed the quantification of retinol and α-tocopherol contents in plasma and fat, the amount of kidney fat, lipid oxidation, and some fat color parameters as potential markers. The results showed that plasma retinol concentrations were higher in kids fed feeding systems with synthetic vitamins. The plasma α-tocopherol concentrations were higher in kids fed grass-based feeding systems (which contain the natural forms of these vitamins). A dilution effect was shown for the retinol concentration in fat. Collectively, the analyzed variables allowed a discriminant analysis to correctly classify kids according to their feeding system and could ensure traceability to consumers. The effects of Payoya kid feeding systems on the fat-soluble vitamin (retinol/α-tocopherol) contents, fat content, fat color, and the oxidation index were evaluated to determine their potential for use as feeding system traceability tools. Four groups of Payoya kids (55 animals in total) fed milk exclusively were studied: a group fed a milk replacer (MR) and three groups fed natural milk from dams reared with different management systems (mountain grazing (MG), cultivated meadow (CM) and total mixed ration (TMR)). Kids were slaughtered around one month of age and 8 kg of live weight. Kids from the MG and CM groups presented lower retinol (5.56 and 3.72 µg/mL) and higher α-tocopherol plasma (11.43 and 8.85 µg/mL) concentrations than those from the TMR and MR groups (14.98 and 22.47 µg/mL of retinol; 2.49 and 0.52 µg/mL of α-tocopherol, respectively) (p < 0.001). With respect to fat, kids with a higher intramuscular fat percentage (CM and TMR groups) had lower retinol contents (16.52 and 15.99 µg/mL, respectively) than kids from the MG and MR groups (26.81 and 22.63 µg/mL, respectively) (p < 0.001). A dilution effect of vitamins on fat was shown: the higher the amount of fat, the lower the vitamin concentrations, the higher the lipid oxidation index (MDA), and the lower the SUM (absolute value of the integral of the translated spectra between 450 and 510 nm). A discriminant analysis that included all studied variables showed that 94.4% of the kids were classified correctly according to their feeding system and could allow traceability to the consumer. [ABSTRACT FROM AUTHOR]

The demand for animal products (e.g. dairy and beef) in tropical regions is expected to increase in parallel with the public demand for sustainable practices, due to factors such as population growth and climate change. The necessity to increase animal production output must be achieved with better management and production technologies. For this to happen, novel research methodologies, animal selection and postgenomic tools play a pivotal role. Indeed, improving breeder selection programs, the quality of meat and dairy products as well as animal health will contribute to higher sustainability and productivity. This would surely benefit regions where resource quality and quantity are increasingly unstable, and research is still very incipient, which is the case of many regions in the tropics. The purpose of this review is to demonstrate how omics-based approaches play a major role in animal science, particularly concerning ruminant production systems and research associated to the tropics and developing countries. Environmental conditions in the tropics make livestock production harder, compared to temperate regions. Due to global warming, the sustainability of livestock production will become increasingly problematic. The use of novel omics technologies could generate useful information to understand adaptation mechanisms of resilient breeds and/or species. The application of omics to tropical animal production is still residual in the currently available literature. With this review, we aim to summarize the most notable results in the field whilst encouraging further research to deal with the future challenges that animal production in the tropics will need to face. Unlabelled Image • Tropical animal production systems are subjected to harsh conditions that limit production sustainability • Omics technologies provide insight to resilience mechanisms and product quality at the molecular level • Application of omics in the tropical animal production context could help improve the productivity of low-resource areas [ABSTRACT FROM AUTHOR]

Simple Summary: The consumption of docosahexaenoic acid (DHA) has beneficial effects on human health. Meat from suckling goat kids is highly valuable, especially in Mediterranean countries. Based on this, several strategies have been implemented to increase the content of DHA in foodstuffs such as meat and meat products. Several studies have observed how feeding diverse sources of DHA can improve the fatty acid profile in goat kid meat. However, few studies have focused on the effect of using these DHA supplements on growth and the immune system development in these animals. Consequently, this study aimed to evaluate the effect of different levels of DHA supplementation on growth and the immune system development in newborn goat kids. The current study showed that the DHA supplementation did not affect either growth or the immune status of goat kids during the first 35 days of life. Consumption of polyunsaturated fatty acids (PUFA), especially docosahexaenoic acid (DHA), has beneficial effects for consumers' health. Consequently, there is an increased interest in enhancing meat fatty acid profiles (i.e., PUFA and DHA content) through diverse nutritional strategies. This study aimed to investigate the effect of supplementing a microalgae-derived product rich in DHA on growth and immune system development in newborn goat kids. In this experiment, newborn goat kids were fed milk replacer (MR) supplemented with three levels of a microalgae-derived product rich in DHA (DHA-Gold®, Martek Biosciences, MD, USA). Groups were designed as follows: MR-NS (milk replacer without DHA-Gold® supplementation; n = 10), MR-DHA-9 (9 g of DHA-Gold®/L milk replacer; n = 10) and MR-DHA-18 (18 g of DHA-Gold®/L milk replacer; n = 10). The immune status of the kids was evaluated by the plasma IgG and IgM concentrations, as well as by the complement system and chitotriosidase activities. Dietary supplementation with DHA did not affect either growth or innate and humoral immunity (p > 0.05). This study concludes that supplementation with DHA does not cause negative effects on growth and immune status in newborn goat kids. [ABSTRACT FROM AUTHOR]