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1.
J Food Sci Technol ; 61(5): 950-957, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38487278

RESUMO

Although the identification of animal species and muscles have been reported previously, no studies have been found on the use of NIR spectroscopy to identify individual animals from the analysis of commercial meat cuts. The aim of this study was to evaluate the use of a portable near infrared (NIR) instrument combined with classical chemometrics methods [principal component analysis (PCA) and partial least squares discriminant analysis PLS-DA)] to identify the origin of individual goat animals using the spectral signature of their commercial cut. Samples were collected from several carcasses (6 commercial cuts x 24 animals) sourced from a commercial abattoir in Queensland (Australia). The NIR spectra of the samples were collected using a portable NIR instrument in the wavelength range between 950 and 1600 nm. Overall, the PLS-DA models correctly classify 82% and 79% of the individual goat samples using either the goat rack or loin cut samples, respectively. The study demonstrated that NIR spectroscopy was able to identify individual goat animals based on the spectra properties of some of the commercial cut samples analysed (e.g. loin and rack). These results showed the potential of this technique to identify individual animals as an alternative to other laboratory methods and techniques commonly used in meat traceability.

2.
Trop Anim Health Prod ; 52(6): 2769-2786, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32500411

RESUMO

In the intensification of sheep production systems, feedlot finishing plays a fundamental role in preparing lambs for slaughter, as well as relieving the grazing pressure on pasture. The profit margins in feedlot operations are often narrow and require the economics of scale to generate a sufficient income. In order to minimise expenses, intensive management and precision rearing of lambs to an ideal slaughter weight is needed to obtain premium carcass prices. The South African sheep industry is made up of wool, dual-purpose as well as meat type breeds, which also vary in terms of maturity. In order to implement precision finishing of South African lamb, a complete understanding of the growth, intake and fat deposition trends of growing lambs of different breed types is needed. This review outlines feedlot lamb production within the Southern African context for the major commercial breeds, while also providing insight in the considerations necessary to develop a decision support system for lamb rearing. Integrating such a decision support system into a lamb feedlot operation can then be used for precision finishing of lambs by predicting the optimal length of the feeding period and ideal slaughter weights of lambs.


Assuntos
Criação de Animais Domésticos , Carne Vermelha , Carneiro Doméstico , Animais , Peso Corporal , Carne , África do Sul ,
3.
Br Poult Sci ; 56(3): 325-9, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25735889

RESUMO

1. South Africa currently produces 70% of the world's ostrich products. The profit margin of South African producers from the sale of ostrich meat, leather and feathers currently stands at 20%, 65% and 15%, respectively. 2. Local producers want to increase the production of ostrich products but keep production costs as low as possible. Maintaining optimal nutrition of breeding stock is necessary to increase the production of ostrich chicks, thereby decreasing the fixed costs per chick. 3. This research examined the impact on ostrich reproduction of replacing soya oilcake (SOC) as a protein supplement with cheaper cottonseed oilcake (CSOC). Although there are no data available on the impact of CSOC feed on ostrich reproduction, it is well known that gossypol, a naturally occurring toxin in cotton plants, negatively affects male reproduction in other monogastric species and that it may also reduce appetite. 4. Ninety-six breeding ostrich pairs were divided into two groups to compare the effects of diet (CSOC and SOC) during the breeding season on ostrich-breeding parameters. The replacement of SOC with CSOC had no significant effect on the number of total eggs produced (47.8 ± 5.3 versus 48.3 ± 5.1 per breeding pair, respectively) or infertile eggs (31.5 ± 3.9 versus 38.0 ± 5.2, respectively). Also, the number of dead-in-shell chicks did not differ significantly between groups (20.2 ± 3.3 versus 26.8 ± 3.8, respectively). 5. Even though none of these breeding parameters differed, the replacement of SOC with CSOC in the diets of breeding birds led to significantly more chicks hatching per hen from breeding birds fed on the SOC (36.1 ± 4.8) than the CSOC diet (17.2 ± 3.8). 6. Although it would thus seem that feeding breeding ostriches CSOC instead of SOC as a protein supplement will have a detrimental effect on chick production, more data are required to deliver a definitive answer.


Assuntos
Criação de Animais Domésticos/métodos , Óleo de Sementes de Algodão/metabolismo , Proteínas Alimentares/metabolismo , Struthioniformes/fisiologia , Ração Animal/análise , Criação de Animais Domésticos/economia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Óleo de Sementes de Algodão/administração & dosagem , Dieta/veterinária , Proteínas Alimentares/administração & dosagem , Suplementos Nutricionais/análise , Relação Dose-Resposta a Droga , Feminino , Gossipol/metabolismo , Masculino , Distribuição Aleatória
4.
Br Poult Sci ; 55(5): 610-8, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25266635

RESUMO

The effects of different dietary energy concentrations on ostrich production variables were examined in two separate trials. The first trial tracked changes in production variables from the pre-starter phase through the starter phase and grower phase. The second trial was based on the finisher phase per se. In both trials, the influence of dietary energy on feed intake, feed conversion ratio (FCR) and growth variables was investigated. Additionally, basic abattoir weights were recorded, and measurements of the feathers and skin were performed. In both trials, three diets with different concentrations of dietary energy were given during each phase where the low-, medium- and high-energy concentrations for each phase were as follows: 13.5, 14.5 and 15.5 MJ ME/kg feed pre-starter; 12.5, 13.5 and 14.5 MJ ME/kg feed starter; 10.5, 11.5 and 12.5 MJ ME/kg feed grower and 9.5, 10.5 and 11.5 MJ ME/kg feed finisher. Feed and water were available ad libitum in both trials. Overall, it was found that the best performance for growth, FCR, skin size and grade, live weight, carcass weight and thigh weight were obtained on the medium-energy diet during the pre-starter, starter and grower phases. During the finisher phase, improved growth rate and tanned skin size was found in birds given the diet with the highest energy concentration (11.5 MJ ME/kg feed). Carcass weight, growth rate and certain feather variables were also significantly influenced by gender.


Assuntos
Dieta/veterinária , Ingestão de Energia , Necessidades Nutricionais , Struthioniformes/crescimento & desenvolvimento , Struthioniformes/metabolismo , Ração Animal/análise , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Composição Corporal/efeitos dos fármacos , Feminino , Masculino
5.
Br Poult Sci ; 55(4): 510-7, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-25132424

RESUMO

1. Feeding costs are the largest expense in an ostrich production system, and protein is one of the more expensive components of the diet. This study evaluated the growth response of ostrich chicks on diets containing different concentrations of protein (amino acids). The diets were formulated to contain three concentrations of protein (one diet with 20% less protein than the conventional concentration, L; one diet with the conventional concentration of protein, M and one diet with 20% more protein than the conventional concentration, H) for each of the phase diets. The phase diets were pre-starter, starter, grower and finisher. 2. This study includes the analysis of ostrich body weight (BW) by modelling growth with linear polynomial and non-linear functions for all the data not separated for treatments. In total, 3378 BW recordings of 90 animals were collected weekly from hatch (d 0) to 287 d (41 weeks) of age. 3. Seven non-linear growth models and three linear polynomial models were fitted to the data. The growth functions were compared by using Akaike's information criterion (AIC). For the non-linear models, the Bridges and Janoschek models had the lowest AIC values for the H treatment, while the Richards curve had the lowest value for M and the von Bertalanffy for the L treatment. 4. For the linear polynomial models, the linear polynomial of the third degree had the lowest AIC values for all three treatments, thus making it the most suitable model for the data; therefore, the predictions of this model were used to interpret the growth data. Significant differences were found between treatments for growth data. 5. The results from this study can aid in describing the growth of ostriches subjected to optimum feeding conditions. This information can also be used in research when modelling the nutrient requirements of growing birds.


Assuntos
Aminoácidos/metabolismo , Fenômenos Fisiológicos da Nutrição Animal , Proteínas Alimentares/metabolismo , Struthioniformes/crescimento & desenvolvimento , Aminoácidos/administração & dosagem , Ração Animal/análise , Animais , Peso Corporal/efeitos dos fármacos , Dieta/veterinária , Proteínas Alimentares/administração & dosagem , Relação Dose-Resposta a Droga
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 322: 124716, 2024 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-38991617

RESUMO

The objective of this study was to evaluate the ability of a handheld near-infrared device (900-1600 nm) to predict fertility and sex (male and female) traits in-ovo. The NIR reflectance spectra of the egg samples were collected on days 0, 7, 14 and 18 of incubation and the data was analysed using principal component analysis (PCA), linear discriminant analysis (LDA) and support vector machines classification (SVM). The overall classification rates for the prediction of fertile and infertile egg samples ranged from 73 % to 84 % and between 93 % to 95 % using LDA and SVM classification, respectively. The highest classification rate was obtained on day 7 of incubation. The classification between male and female embryos achieved lower classification rates, between 62 % and 68 % using LDA and SVM classification, respectively. Although the classification rates for in-ovo sexing obtained in this study are higher than those obtained by chance (50 %), the classification results are currently not sufficient for industrial in-ovo sexing of chicken eggs. These results demonstrated that short wavelengths in the NIR range may be useful to distinguish between fertile and infertile egg samples at days 7 and 14 during incubation.


Assuntos
Galinhas , Fertilidade , Análise de Componente Principal , Espectroscopia de Luz Próxima ao Infravermelho , Máquina de Vetores de Suporte , Animais , Espectroscopia de Luz Próxima ao Infravermelho/métodos , Feminino , Masculino , Fertilidade/fisiologia , Análise Discriminante , Óvulo/química , Análise para Determinação do Sexo/métodos , Embrião de Galinha
7.
Food Res Int ; 180: 114047, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38395546

RESUMO

The objective of this study was to evaluate the use of a portable near infrared (NIR) instrument to monitor the shelf-life of four goat muscles [longissimus thoracis et lumborum (LTL), semimembranosus (SM), semitendinosus (ST) and biceps femoris (BF)] stored for up to 8 days (4 °C). The NIR spectra of the muscle samples were collected at day 0, and after 1, 4 and 8 days of storage using a MicroNIR instrument (900-1600 nm). The coefficient of determination in cross-validation (R2) and the standard error in cross validation (SECV) obtained for the prediction of days of storage ranged between 0.76 and 0.86, where the SECV ranged from 0.32 to 0.41. The best statistics in cross-validation were obtained for the prediction of days of storage in the BF samples, followed by the ST and LTL muscles. Differences in the PLS loadings for the cross-validation models were observed due to the interactions between the different muscle samples and days of storage. Overall, these results showed the potential of NIR spectroscopy to identify the time of storage in four different goat muscles. Similar data and techniques could be used to predict the remaining shelf life of meat derived from different species under storage. This information can then be used as a tool to predict and guarantee the safety of meat samples to the consumer along the meat supply and value chains.


Assuntos
Cabras , Músculos Isquiossurais , Animais , Músculos , Espectroscopia de Luz Próxima ao Infravermelho , Carne/análise
8.
J S Afr Vet Assoc ; 82(3): 170-5, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22332302

RESUMO

The health and quality compliance of game carcasses (n = 295) intended for the South African export market and aspiring to comply with the strict hygiene requirements of the European Union were compared with game carcasses (n = 330) available for the local market and currently not subjected to meat safety legislation. Samples were collected in similar seasons and geographical areas in South Africa from 2006 to 2009. Aerobic plate counts (APC) of the heart blood verified that both groups possessed similar ante mortem bacterial status. For health compliance APC, tests for Escherichia coli, Salmonella spp. and Staphylococcus aureus were performed on the carcasses. Surfaces of the local carcasses were swabbed using the European Enviro-biotrace sponge technique at 3 and 72 h post mortem. Unskinned but eviscerated export carcasses in the abattoir were skinned and sampled by incision using a corkborer 72 h post mortem. Temperature and pH readings were recorded at 3 and 72 h post mortem from the longissimus dorsi muscle and the readings at 3 h differed (P = 0.035). Temperatures at 72 h were lower for export than local carcasses (P < 0.001) because of earlier introduction and maintenance of the cold chain. The pH readings also differed between groups at 3 and 72 h (P < 0.001). APC results for the local group exceeded the maximum permissible count (< 10(5)). S. aureus results showed differences (P < 0.001), with readings from the local group being higher. The same tendency was exhibited for E. coli (P = 0.008). Imposition of hygiene guidelines for game ranchers producing meat for the local market is therefore recommended.


Assuntos
Contaminação de Alimentos/análise , Manipulação de Alimentos/métodos , Inocuidade dos Alimentos , Carne/normas , Controle de Qualidade , Matadouros , Animais , Animais Selvagens , Microbiologia de Alimentos , Humanos , Higiene , Legislação sobre Alimentos , África do Sul
9.
J S Afr Vet Assoc ; 82(4): 205-12, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22616433

RESUMO

A confirmed case of human brucellosis motivated an investigation into the potential source of infection in Namibia. Since domestic animals are principal sources of Brucella infection in humans, 1692 serum samples were screened from sheep, goats and cattle from 4 presumably at-risk farms and 900 springbok (Antidorcas marsupialis) serum samples from 29 mixed farming units for Brucella antibodies by the Rose-Bengal test (RBT) and positive cases confirmed by complement fixation test (CFT). To assess the prevalence of human brucellosis, 137 abattoir employees were tested for Brucella antibodies using the standard tube agglutination test (STAT) and by enzyme linked immunosorbent assay (ELISA). Cattle and sheep from all 4 farms were negative by RBT and CFT but 2 of the 4 farms (Ba and C) had 26/42 and 12/285 seropositive goats, respectively. Post mortem examination of seropositive goats revealed no gross pathological lesions typical of brucellosis except enlarged mesenteric and iliac lymph nodes seen in a single buck. Culture for brucellae from organs of seropositive animals was negative. None of the wildlife sera tested positive by either RBT or CFT. Interviews revealed that besides the case that prompted the investigation, a family and another person from other farms with confirmed brucellosis shared a common history of consumption of unpasteurised goat milk, home-made goat cheese and coffee with raw milk and prior contact with goats, suggesting goats as the likely source of infection. All 137 abattoir employees tested negative by STAT, but 3 were positive by ELISA. The 3 abattoir workers were clinically normal and lacked historical connections with clinical cases. Although goats are often associated with B. melitensis, these studies could not explicitly implicate this species owing to cross-reactivity with B. abortus, which can also infect goats. Nevertheless, these data reinforce the need for a better National Control Programme for brucellosis in Namibia.


Assuntos
Anticorpos Antibacterianos/sangue , Brucelose/transmissão , Brucelose/veterinária , Contaminação de Alimentos/análise , Zoonoses , Matadouros , Animais , Brucella/imunologia , Brucelose/epidemiologia , Bovinos , Doenças dos Bovinos/epidemiologia , Doenças dos Bovinos/transmissão , Queijo/microbiologia , Feminino , Microbiologia de Alimentos , Doenças das Cabras/epidemiologia , Doenças das Cabras/transmissão , Cabras , Humanos , Masculino , Leite/microbiologia , Namíbia/epidemiologia , Estudos Soroepidemiológicos , Ovinos , Doenças dos Ovinos/epidemiologia , Doenças dos Ovinos/transmissão
10.
J S Afr Vet Assoc ; 81(4): 224-7, 2010 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21526737

RESUMO

Information on the effect of road transportation conditions and lairage times on the meat quality of pork under South African conditions is very sparse. In this investigation, the effects of 2 road conditions (rough road with frequent stops - A; smooth road, few stops - B) and 2 lairage holding periods (2 h and 24 h) on the physical meat quality attributes of commercially produced pigs during summer (ambient temperatures > 30 degrees C) in the Western Cape (South Africa) were investigated. Pig meat from pigs transported on a road that caused more stress (A), had lower pH 45 (measured 45 min post mortem) values after 2 h lairage than pigs transported over a smoother road. Pigs B had a lower muscle pH 24 (measured 24 h post mortem) than group A, indicating that they had more glycogen reserves available for post mortem glycolysis. Road conditions A were more stressful resulting in a higher incidence of PSE pork, as shown by the percentage drip loss and the L* values. When the lairage period was increased to 24 h prior to slaughter, pigs transported under road conditions A had time to replenish their energy reserves and the pH 45, drip loss and L* values were within an acceptable range. However, pigs transported under road conditions B had lower pH 45 and higher pH 24 values, indicating that the lairage period was too long and that energy reserves were depleted in order to adapt to the stressful conditions. Results from this investigation indicate that improvement of the transport/road conditions will result in better pork quality.


Assuntos
Carne/normas , Criação de Animais Domésticos , Animais , Clima , África do Sul , Estresse Fisiológico , Suínos/fisiologia , Fatores de Tempo , Meios de Transporte
11.
J S Afr Vet Assoc ; 81(3): 151-5, 2010 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21247040

RESUMO

The prevalent microbial growth on carcasses before and after overnight cooling in an ostrich abattoir and de-boning plant was investigated. The effect of warm or cold trimming of the carcasses was examined together with possible causes of contamination along the processing line. An attempt was made to link the prevalent microorganisms that were identified from carcasses to those from specific external contamination sources. Samples of carcasses and possible contaminants were collected in the plant, plated out and selected organisms were typed using a commercial rapid identification system. It was indicated that the cold trim (mainly of bruises) of carcasses was advantageous in terms of microbiological meat quality. Results indicated pooled water in the abattoir as the most hazardous vector for carcass contamination and that contaminants from this source are mostly Gram-negative pathogens. Pseudomonas and Shigella were frequently isolated from surface and air samples and indicated that the control of total plant hygiene is a requirement for producing ostrich meat that is safe to consume and has an acceptable shelf-life.


Assuntos
Bactérias/isolamento & purificação , Carne/microbiologia , Struthioniformes/microbiologia , Matadouros , Animais , Microbiologia de Alimentos , África do Sul
12.
Meat Sci ; 83(4): 737-43, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20416629

RESUMO

Game meat has distinct sensory characteristics and favourable fatty acid profiles which differ between species. The SFA's percentage was found to be higher in impala meat (51.12%) than kudu meat (34.87%) whilst the total PUFA was higher in kudu (38.88%) than impala (34.06%). Stearic acid (22.67%) was the major fatty acid in impala and oleic acid in kudu (24.35). Linoleic acid, C20:3n-6 and C22:6n-3 were higher in kudu while C20:4n-6, C20:5n-3 and C22:5n-3 were higher in impala. The PUFA:SFA ratio for kudu (1.22) was higher than for impala (0.73) while impala had a higher n-6 PUFA's to n-3 PUFA ratio (3.76) than kudu (2.20). Kudu was higher in cholesterol (71.42±2.61mg/100gmuscle) than impala (52.54±2.73mg/100gmuscle). Sensory evaluation showed impala had a more intense game aroma and flavour while the initial juiciness of cooked samples of kudu was higher. The results show kudu and impala can be marketed for their unique flavours and aromas as well as being a healthy substitute for other red meats.

13.
Meat Sci ; 83(4): 788-95, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-20416621

RESUMO

The meat quality of kudu and impala was compared. Live weight and carcass weight differed between species, genders and age groups. Impala had the highest dressing percentage while kudu had the highest live weight and carcass weight. Kudu had the lowest fat content while female animals had a higher fat and myoglobin content than males. Sub-adults had a higher ash content than adults. Species, gender and age had no effect of pH, drip loss, cooking loss or tenderness although kudu had higher L∗, a∗, b∗ and chroma values than impala. Impala sub-adults had significantly higher insoluble collagen, soluble collagen, total collagen and hydroxyproline content than kudu sub-adults. Kudu had the highest potassium levels while impala had the highest phosphorus levels. Potassium, sodium, iron and copper levels also differed between species.

14.
Animal ; 13(9): 1952-1961, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30654851

RESUMO

Immunocastration provides a less invasive means of castrating lambs. Considering increasing consumer awareness, the efficacy of this technique on commercial slaughter lambs needs to be further investigated and its effects on growth and stress responses need to be established. This study compared the growth rate, testes size and stress responses of immunocastrated lambs with that of lambs physically castrated with a Burdizzo clamp, as well as intact rams. A total of 40 Dohne Merino ram lambs (average live weight = 45.4±3.68 kg) were randomly allocated to the following four treatment groups: control (intact; R), Burdizzo-castrated (on day 2; B), immunocastrated with a 4-week (ICS4), or a 6-week (ICS6) interval between the second immunocastration vaccination and slaughter. Within the immunocastration treatments, the reaction to vaccination was assessed through injection site scoring, recording the local injection site surface temperature and assigning a walking score. The response to Burdizzo castration was assessed by scoring the reaction during the procedure, testes palpation reaction, walking gait and measuring testis temperature. Additional parameters recorded included BW, serum cortisol concentration, scrotal circumference and rectal temperature. Pain behaviours were described for the short-, medium- and long-term effects after the two methods of castration. Predominantly, tissue-hardening and bruising occurred at the injection sites of immunocastrates, but little effect was observed on walking comfort and no effect on injection site temperature or rectal temperatures. After Burdizzo castration, lambs spent more time in abnormal postures, and from day 3 (D3) to D8 of the trial, discomfort was observed during testes palpation and walking in B lambs. Serum cortisol concentrations were elevated in B lambs on D3 and D15, indicating physiological stress. Thus, immunocastration improved the welfare of castrated lambs as assessed by cortisol secretion, scrotal swelling and pain behaviours, without influencing growth rate.


Assuntos
Hormônio Liberador de Gonadotropina/metabolismo , Ovinos/fisiologia , Vacinação , Animais , Humanos , Hidrocortisona/sangue , Masculino , Orquiectomia/veterinária , Escroto/crescimento & desenvolvimento , Ovinos/crescimento & desenvolvimento , Ovinos/imunologia , Estresse Fisiológico , Testículo/fisiologia , Fatores de Tempo
15.
Animal ; 13(9): 1962-1971, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30651155

RESUMO

Immunocastration improves the welfare of castrated commercial slaughter lambs; however, the time-point at which this technique influences semen quality and sperm production has not yet been established for various vaccination schedules. Furthermore, the effect of extended intervals between second vaccination and slaughter needs to be investigated regarding continued testosterone suppression in immunocastrated lambs. The effect of extending the interval between second immunocastration vaccination and slaughter from four to six weeks on the reproductive capacity of Dohne Merino lambs was examined. A total of 40 Dohne Merino lambs were stratified according to initial weight (45.4±3.68 kg) and randomly assigned to four treatments that included intact control rams (R), Burdizzo-castrated lambs (B) and lambs immunocastrated with either four (ICS4) or six (ICS6) weeks between second vaccination and slaughter. Blood and semen samples were collected throughout the study period to determine serum testosterone concentrations, evaluate semen quality and assess sperm viability. Semen samples from R showed improvement over the trial. Throughout the collection period, B lambs had low serum testosterone concentrations, poor sperm motility and sperm viability, as expected. However, a slight increase in the percentage of live sperm in semen samples from B lambs towards the end of the collection period indicated poor success rates of the technique in some lambs. Burdizzo-castration also caused testes tissue necrosis and abscessing, indicating physiological stress. Semen appearance scores varied for both immunocastrated treatments, but the mass motility scores decreased over time. The ICS6 lambs showed a consistent and continuous decline in serum testosterone concentrations and sperm viability, with an increased percentage of dead abnormal sperm in the semen samples at the end of the study. The ICS4 treatment was successful in interrupting serum testosterone production and reducing semen quality; however, not as consistently as the ICS6 treatment. Primary immunocastration vaccination influenced serum testosterone concentrations but consistently low levels were only realised for both treatments after secondary vaccination. Although all castration treatments influenced testes size and colour, the six-week vaccination-to-slaughter interval caused a greater decrease in testes cut surface L* (lightness) colour values and in seminiferous tubule circumference. Extending the interval between second immunocastration vaccination and slaughter resulted in a more consistent and reliable influence on reproductive capacity of immunocastrated lambs. Thus, immunocastration is a suitable alternative to Burdizzo-castration regarding the interruption of testosterone production and testis functioning.


Assuntos
Bem-Estar do Animal , Reprodução , Ovinos/fisiologia , Vacinação/veterinária , Animais , Peso Corporal , Hormônio Liberador de Gonadotropina/metabolismo , Masculino , Orquiectomia/veterinária , Análise do Sêmen/veterinária , Ovinos/imunologia , Motilidade dos Espermatozoides/fisiologia , Espermatozoides/fisiologia , Testículo/fisiologia , Testosterona/sangue , Fatores de Tempo
16.
Mar Pollut Bull ; 141: 529-534, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30955765

RESUMO

Mussels pose health risks to consumers through accumulation of trace metals from the ocean. Saldanha Bay, South Africa, has heavy industry and international shipping, creating concerns over pollution levels for aquaculture facilities. Samples of C. meridionalis and M. galloprovincialis were collected from mussel rafts over two-years and analysed for trace metal content using Inductively Coupled Plasma Mass Spectrometry. Aluminium, Cr, Fe, Zn, Cd and Pb were higher in M. galloprovincialis, while C. meridionalis accumulated more Cu and Mn. Temporal fluctuations occurred for Fe and As concentrations in C. meridionalis, and Fe, As, Hg and Pb in M. galloprovincialis. Arsenic exceeded South African regulatory limits (3 mg/kg) once in each species (max = 3.4 mg/kg w.w.). Lead concentrations in M. galloprovincialis were within EU regulatory limits for bivalves (1.5 mg/kg) but exceeded SA regulatory limits for fish (0.5 mg/kg) four times. Overall, farmed mussels from Saldanha Bay were determined to be safe for human consumption.


Assuntos
Bivalves/química , Contaminação de Alimentos/análise , Metais/análise , Frutos do Mar/análise , Poluentes Químicos da Água/análise , Animais , Aquicultura , Arsênio/análise , Bivalves/metabolismo , Monitoramento Ambiental/métodos , Humanos , Concentração Máxima Permitida , Mercúrio/análise , Mytilus/química , Mytilus/metabolismo , Medição de Risco , África do Sul
17.
Meat Sci ; 147: 20-27, 2019 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-30179719

RESUMO

The effect of olive oil inclusion on the chemical and sensory characteristics in cabanossi made with ostrich and warthog meat was investigated. Ostrich meat from soybean oilcake (SBOC) and cottonseed oilcake dietary inclusion levels (CSOC), and olive oil were included at three levels (0%, 1% and 2%) resulting in six treatments. The fat content in the cabanossi increased with increasing levels of oil inclusion but were all <10%, which allows it to be classified as a low fat meat product. Total monounsaturated fatty acids in the cabanossi increased whilst total saturated fatty acids and total polyunsaturated fatty acids decreased as olive oil increased. The SBOC cabanossi had a lower fat and higher crude protein content. The inclusion of olive oil at 2% resulted in a cabanossi with increased tenderness, juiciness and cured red meat colour, all factors that appeal to the consumer, while the overall flavour descriptors were not adversely affected by the inclusion of olive oil.


Assuntos
Ração Animal/análise , Ácidos Graxos/análise , Produtos da Carne/análise , Azeite de Oliva , Animais , Cor , Óleo de Sementes de Algodão , Dieta/veterinária , Humanos , Glycine max , Struthioniformes , Suínos , Paladar
18.
Meat Sci ; 80(1): 94-100, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22063174

RESUMO

The current knowledge of the yield and nutritional (proximate and fatty acid) composition of meat derived from African ungulates, camelidae, rodents, ratites and reptiles is reviewed. Although most of the species discussed give low cholesterol levels consistent with their low meat lipid contents, the tegu lizard gives a very low level (18.2mg/100g tissue). The fatty acid profiles of the various species all have low saturated fatty acids and high polyunsaturated fatty acids resulting in favourable saturated to polyunsaturated fatty acid ratios. Although the springbok, camel, ostrich and crocodile are marketed and exported to sophisticated markets, the rodents are the species that show most promise in becoming large commercial commodities. Not only is their meat desirable and nutritional, but they are also highly adaptable to extensive and intensive production systems.

19.
Meat Sci ; 80(4): 1055-60, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22063836

RESUMO

Consumers expect beef products to be juicy and tender. In the present investigation four beef muscles, i.e. Biceps femoris (BF), Longissimus lumborum (LL), Rectus femoris (RF) and Semitendinosus (ST), were infused with a blend consisting of sodium and potassium salts, di- and triphosphates and lactates. The muscles were stored at 4°C for 24h, followed by storage at -18°C until the descriptive sensory analysis could be performed on all four muscles. BF and LL were also subjected to consumer sensory analysis to determine the overall degree of liking. The infused and non-infused samples did not differ significantly with regard to aroma and flavour. The infused samples were significantly more juicy and tender than the untreated samples. Although the infused samples were rated significantly higher in salty taste than the untreated samples, both treatments illustrated a relatively low mean value for saltiness. Both the infused LL and BF samples illustrated a high degree of liking. Therefore, the infusion of beef muscles with a blend containing phosphates and lactates could be applied successfully to enhance the sensory attributes of beef.

20.
Meat Sci ; 79(2): 365-74, 2008 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22062765

RESUMO

Meat derived from three genotypes of ostrich, resulting from breeding South African Black (Black) ostriches and Zimbabwean Blue (Blue) ostriches as well as their hybrid, was analysed for physical and sensory quality. Ostriches of a commercially standard slaughter age of 14 months, raised under the same environment were used. The pH(24) was the highest in the pure Blue genotype and therefore meat from this genotype was the darkest and the percentage drip loss and cooking loss the lowest. When comparing the pure Blue genotype to the pure Black genotype, 70% of the muscles had a higher pH(24), 50% of the muscles were redder and significantly less saturated in colour, 67% of the muscles had a lower percentage drip loss and 50% of the muscles had a lower percentage cooking loss. No significant genotypic differences were found regarding the instrumental toughness, nor the sensory attributes of the meat.

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