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SIMPLE SUMMARYMuscle 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.

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.

AbstractMost 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.HighlightsMeat 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.

AbstractMost 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.HighlightsGoat 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.

AbstractThe 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.HighlightsOrganic 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.

ABSTRACTRefractometry 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 r2for 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.

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.

Tissue percentages (secretory, connective, ductal and vascular tissues) and the number and size of the alveoli in the udders of three dairy goat breeds under two milking frequencies (once- vs. twice-daily milking) were studied. Nine dairy goats, three of each breed studied (Majorera, Tinerfeña and Palmera), were milked during 6 weeks beginning at the tenth week of lactation. The right udder half was milked twice daily, and the left udder half was milked once daily. Moreover, during the experimental period, morphological udder data, milk yield, milk fractioning and milk composition were recorded. The goats were sacrificed and two samples for each gland were taken for the histological study. The statistical analyses revealed that the histological parameters were not influenced by the milking frequency, and that the breed determines different percentage of tissue components. Correlations between morphological parameters of the udder and milk-yielding parameters were high and determined the greater importance of the globosity and the structure of the udder in the milk production. Furthermore, it was determined that the percentage of secretory tissue in the mammary parenchyma has no correlation with the milk yield parameters in different high-production dairy breeds. Histological parameters (secretory and connective tissues) only have an impact in the milk fractions.

The market for goat milk cheese has grown due to the new tendencies to consume innovative products, and the fact that it has provided a profitable alternative to cow milk cheese due to its inherent health-promoting attributes. The trends toward healthier eating have increased the interest in low-fat cheese (LFC). The objective of this study is to enable an understanding and provides a baseline of the effect of fat reduction on sensory analyses and consumer acceptability of cheeses made from raw goat milk with three different fat contents and ripened for 28 days using an artisanal method. Odour and flavour intensity was lower as fat decreased in cheese, and LFC and reduced-fat cheese (RFC) were firmer, friable, grainier, drier, acidic and less adhesive and sweet than full-fat cheese (FFC). Both judges and consumers preferred the FFC, mainly because of the greater intensity and the combination of this with excessive hardness and high masticability was likely the main cause of non-acceptance.

The primary focus of this study was the accurate classification of limb skeletal muscle fiber types in adult goats (Capra hircus) according to the myosin heavy chain (MHC) isoform they express. Combined methodologies of gel electrophoresis, immunoblotting, immunohistochemistry, myofibrillar ATPase (mATPase), and quantitative metabolic enzyme histochemistry of M. semitendinosussamples were developed. Three MHCs were identified and tentatively designated as types I, IIA, and IIX. Five fiber types were defined immunohistochemically according to their MHC content: I, I+IIA, IIA, IIAX, and IIX. The hybrid fast‐twitch fibers (IIAX) totaled 21% of the fiber population analyzed. The three major pure fibers (I, IIA, and IIX) could be objectively separated upon the basis of their mATPase activities after acid and alkaline preincubations. The prominent number of hybrid fibers, however, could not be delineated with these mATPase methods. Metabolic and size properties of muscle fibers varied according to their MHC content, but overlapped the full range of muscle fiber phenotypes. These integrated data demonstrate that type II skeletal muscle fibers of small ruminants have been misclassified in previous studies. The immunohistochemical approach developed in the present study offers new prospects for muscle fiber typing in caprine experimental studies and meat production technologies. Anat Rec 264:284–293, 2001. © 2001 Wiley‐Liss, Inc.

The primary focus of this study was the accurate classification of limb skeletal muscle fiber types in adult goats (Capra hircus) according to the myosin heavy chain (MHC) isoform they express. Combined methodologies of gel electrophoresis, immunoblotting, immunohistochemistry, myofibrillar ATPase (mATPase), and quantitative metabolic enzyme histochemistry of M. semitendinosus samples were developed. Three MHCs were identified and tentatively designated as types I, IIA, and IIX. Five fiber types were defined immunohistochemically according to their MHC content: I, I+IIA, IIA, IIAX, and IIX. The hybrid fast-twitch fibers (IIAX) totaled 21% of the fiber population analyzed. The three major pure fibers (I, IIA, and IIX) could be objectively separated upon the basis of their mATPase activities after acid and alkaline preincubations. The prominent number of hybrid fibers, however, could not be delineated with these mATPase methods. Metabolic and size properties of muscle fibers varied according to their MHC content, but overlapped the full range of muscle fiber phenotypes. These integrated data demonstrate that type II skeletal muscle fibers of small ruminants have been misclassified in previous studies. The immunohistochemical approach developed in the present study offers new prospects for muscle fiber typing in caprine experimental studies and meat production technologies. Anat Rec 264:284–293, 2001. © 2001 Wiley-Liss, Inc.

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). 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.

Although most of the European goat farms are dairies, there are a significant number of herds dedicated to meat production as the main product. Due to the current policy of food safety in European Union, the traceability, particularly the electronic identification, is taken into consideration; however, the effect of this electronic identification has not been studied on goat kids for fattening. For this reason, the effect of the ruminal bolus on the growth of goat kids and the development of their stomachs were studied. At 16 kg, animals were randomly assigned in two groups: control (n=23) and bolus (n=27), the latter identified with Inoxeramic Bolus. Both of them were slaughtered at 24 kg. Statistical differences in growth parameters and stomach development were not observed, except in the reticulum-omasal orifice diameter, which was bigger in the bolus group. Moreover, when the breed was taken into account (Majorera, Palmera and Tinerfeña), interbreed differences were found in orifice diameter and empty rumen–reticulum weight, due to treatment (P<0.05).

To identify the host range of potential vectors of Dirofilaria immitis Leidy, the causal agent of canine dirofilariasis, we studied the bloodmeal origin of mosquitoes trapped on two of the Canary Islands, Gran Canaria and Tenerife, where this disease is considered hyperendemic. On Gran Canaria, mosquitoes were captured using Centers for Disease Control and Prevention (CDC) traps (outdoors) and resting in a bathroom (indoors). Only CDC traps were used to capture mosquitoes in Tenerife. The species captured in decreasing order of abundance were Culex theileri Theobald, Culex pipiens L., Culiseta longiareolata Macquart, Anopheles atroparvus van Thiel, and Anopheles cinereus Theobald. The origins of bloodmeals were identified for 121 Cx. theileri and 4 Cx. pipiens after amplification and sequencing of a fragment of the vertebrate cytochrome oxidase I (COI) gene. Cx. theileri fed on goats, sheep, dogs, cattle, cats, humans, and chickens, and Cx. pipiens fed on goats and chickens. A lower success of bloodmeal identification was obtained in mosquitoes captured resting indoors than outdoors in CDC traps, probably because of a longer time period between feeding and capture. Although most Cx. theileri fed on ruminants, this species also fed on different mammal species susceptible to dirofiliarasis, including humans, suggesting it could play a role on parasite transmission.