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1.
J Appl Anim Welf Sci ; 24(1): 39-55, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-32364808

RESUMEN

Behavioural and blood-based physiological responses of Nguni (NG) and Boran (BR) steers, following relocation to a new environment and herd regrouping were examined. Ten steers of each genotype aged 9 months and reared under similar conditions were studied over 16 weeks: 1 for acclimatization and baseline measurements in original groups, 15 for post regrouping measurements. Each sampling week, direct visual observations and durations of aggressive and affiliative interactions were recorded between 0500-1900h for 3 conservative days. Blood samples were drawn fortnightly by jugular venipuncture for plasma cortisol, glucose, creatine kinase (CK) and haematological analysis. In weeks 1-5, BR had higher instances of head-butting (P=0.0311), mounts (P=0.0142) and threats (P=0.0241) compared to NG (P<0.0001, P=0.0412 and P=0.0241, respectively). However, these significantly declined from weeks 7-15 in both genotypes. Grooming increased consistently over the weeks in both genotypes (P=0.0214). Head-butting correlated with cortisol (r=-0.116), CK (r=-0.295) and neutrophil-to-lymphocyte ratio (r=-0.144). Grooming correlated (r=0.137) with white-blood-cell-count. Herd regrouping temporarily disrupted social behaviour, with BR showing more aggression towards NG steers. Nevertheless, the two genotypes established some stability within five weeks of social mixing.


Asunto(s)
Bovinos/fisiología , Conducta Social , Agresión , Crianza de Animales Domésticos/métodos , Animales , Conducta Animal , Glucemia/análisis , Bovinos/sangre , Bovinos/genética , Creatina Quinasa/sangre , Aseo Animal , Hidrocortisona/sangre , Recuento de Leucocitos/veterinaria , Masculino , Sudáfrica
2.
Foods ; 9(12)2020 Dec 08.
Artículo en Inglés | MEDLINE | ID: mdl-33302550

RESUMEN

This study compared the use of pork backfat (PF) and fat-tailed sheep tail and backfat (SF) on the physicochemical, fatty acids and sensory attributes of warthog cabanossi. There were no differences between weight loss during drying, moisture content, pH, water activity, salt content and lipid oxidation between the cabanossi types. However, protein and ash contents were higher in PF cabanossi whilst fat content was higher in SF cabanossi. The PF cabanossi had higher polyunsaturated fatty acids (especially n-6), lower monounsaturated fatty acids whilst the saturated fatty acid content was similar between the two cabanossi products. The n-3:n-6 ratio was more beneficial in the SF cabanossi. The descriptive sensory analysis showed two distinct products where PF cabanossi scored higher for most attributes. Although SF cabanossi scored less for these attributes, this cabanossi had unique and acceptable sensory attributes. This study concluded that fat-tailed sheep tail and backfat could be used to produce a unique cabanossi product of acceptable quality.

3.
Parasitol Res ; 119(12): 4169-4175, 2020 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-33063130

RESUMEN

Nematodes and coccidia are major pathogens causing parasitic infections in livestock production. This study aimed to determine the prevalence and seasonality of gastrointestinal helminths and coccidia in communal sheep grazing in humid, semi-humid and arid zones of the Eastern Cape Province. A total of 3299 faecal samples were collected from sheep between January 2012 and December 2015. Of the collected roundworm species (faecal eggs and faecal cultures), Haemonchus contortus was the only species found. The prevalence of gastrointestinal parasites was significantly higher in the humid zone (H. contortus 81% and coccidia 37%), followed by a semi-humid zone (H. contortus 75% and coccidia 22%) and the arid zone was the lowest (H. contortus 71% and coccidia 14%). Haemonchus contortus had significantly higher faecal egg counts (FEC) during spring (1465.73 ± 143.56) and summer (1418.73 ± 160.73) and the lowest during autumn (496.67 ± 219.13) and winter (352.05 ± 164.44) in all agro-ecological zone. The humid zone had significantly higher FEC in seasonal occurrence of H. contortus and coccidia compared with other agro-ecological zones (P < 0.05). There was no significant difference (P > 0.05) observed in the seasonal occurrence of H. contortus species in arid zone. Surprisingly, higher coccidia counts (352.17 ± 43.58) during 2012 winter season in humid zone and in summer season (0.00 ± 559.72) of 2013 in the semi-humid zone than other agro-ecological zones. However, agro-ecological zone differences and seasonal variations had an influence on H. contortus and coccidia distribution and abundance. This study confirms that helminths and coccidia are major causative agents causing parasitic infections in livestock production, and therefore, good animal health management practices including proper hygiene should be followed to prevent parasitic infection in small ruminants.


Asunto(s)
Agricultura/métodos , Coccidios/aislamiento & purificación , Parasitosis Intestinales/veterinaria , Nematodos/aislamiento & purificación , Enfermedades de las Ovejas/parasitología , Animales , Parasitosis Intestinales/epidemiología , Parasitosis Intestinales/parasitología , Ganado/parasitología , Recuento de Huevos de Parásitos/veterinaria , Prevalencia , Estaciones del Año , Ovinos , Enfermedades de las Ovejas/epidemiología , Sudáfrica/epidemiología
4.
Vet Anim Sci ; 9: 100104, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-32734966

RESUMEN

[This corrects the article DOI: 10.1016/j.vas.2017.06.001.].

5.
Parasite Epidemiol Control ; 10: e00157, 2020 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-32642567

RESUMEN

Elephantorrhiza elephantina is a medicinally important plant whose roots are used to control gastrointestinal parasites in goats. The use of plant-based anthelmintics as potential alternatives to synthetic anthelmintics in controlling gastrointestinal worms in ruminants is a promising area of research. The study was carried out to ascertain the efficacy of E. elephantina in controlling goat trematodes. Standard procedures were used to quantify the phytochemicals in the water, ethanol and methanol root extracts of E. elephantina. The quantitative phytochemical analysis revealed that alkaloids (93.24 ± 1.68%), condensed tannins (450.52 ± 0.15 mg CE/g), flavonoids (803.93 ± 0.13 mg QE/g), phenols (476.11 ± 0.37 mg GAE/g) and saponins (83.28 ± 1.72%) were present in E. elephantina root extracts. Paramphistomum cervi adult worms recovered from the rumen of freshly slaughtered goats were used. In vitro screening of ethanol, methanol and water extracts of E. elephantina for potential anthelmintic activity against adult P. cervi worm motility showed time and dose-dependent significant effects. Ethanol extracts showed a highly significant (P < 0.05) inhibition of motility (86.67 and 96.67%) at concentrations 7.5 and 15 mg/mL respectively, after 12 h of treatment, while methanol and water extracts exhibited a significant (P < 0.05) inhibition of motility (96.67 and 66.67% respectively) at concentration of 15 mg/mL 16 h post-exposure. Our findings confirm the efficacy of E. elephantina in controlling goat trematodes.

6.
J Sci Food Agric ; 100(14): 5023-5031, 2020 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29635774

RESUMEN

An increase in the acceptance, demand and production of game meat and venison has been experienced globally. Game meat and venison fit into consumers' ideology of healthy and environmentally friendly meat when compared to domesticated animals. Opportunities exist to explore the use of these meat sources in developing new products, particularly as game meat and venison in their fresh state are sometimes perceived as being tough. Consumers have shown a trend for trying exciting new products with different organoleptic qualities, and fermented sausages occupy a special niche in the gastro-economic trade. In this review, the production potential of game meat and venison and its prospective use in the development of fermented sausages are discussed. Emphasis is placed on the importance of meat characteristics in textural and sensorial development as well as the safety of fermented sausages. Additionally, consumers' perception of venison and game meat is discussed. Possible areas of research and knowledge gaps are highlighted, particularly the potential use of meat with high pH and microbial load. © 2018 Society of Chemical Industry.


Asunto(s)
Productos de la Carne/análisis , Animales , Animales Salvajes , Comportamiento del Consumidor , Ciervos , Fermentación , Humanos , Gusto
7.
Asian-Australas J Anim Sci ; 33(6): 867-878, 2020 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-31480203

RESUMEN

A significant proportion of the African continent is conducive for animal agricultural production, due to its historical experience and available resources to accommodate and nurture various indigenous and exotic animal species and breeds. With food security being a global challenge, animal products can play an important role as nutrient dense food sources in human diets, particularly in Africa. However, this does not seem to reach its full potential in practice, due to numerous reasons that have not been adequately addressed. Animal welfare reservations can be highlighted as one of the major contributing factors to the curbed progress. The consequences have been scientifically proven to affect product quality and market access. However, in the African community, the concept of animal welfare has not been fully embraced. While there are international animal welfare standards in the developed world, there are inherent factors that hinder adoption of such initiatives in most developing regions, particularly among communal farmers. These include cultural norms and practices, social ranking, socio-economic status, available resources, information dissemination and monitoring tools. Therefore, there is need to harmonize what is internationally required and what is feasible to accommodate global variability. The protocols followed to ensure and evaluate farm animal welfare require regular investigation, innovation and a sustainable approach to enhance animal productivity, efficiency and product quality. Additionally, investing in animal wellbeing and health, as well as empowering communities with significant knowledge, has a potential to improve African livelihoods and contribute to food security. This review seeks to highlight the concept of animal welfare in relation to livestock and food production in African conditions.

8.
Meat Sci ; 157: 107887, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31323453

RESUMEN

The study evaluated shelf-life and sensory quality of meat from lambs fed finisher diets containing increasing levels of grape pomace (GP; 0, 5, 10, 15 and 20% GP/kg DM). Color, antioxidant activity and lipid oxidation of the longissimus lumborum were evaluated on different storage times (days 1, 3, 5, 7 and 9) post-slaughter using overwrapped air-permeable packaging. Treatments 0, 10 and 20% GP/kg DM were used for evaluation of protein oxidation and microbial counts on days 1, 5 and 7, while a trained panel assessed the sensory quality on day 1. Diet neither influenced meat color nor sensory quality. Diet × day interactions were observed for antioxidant activity, lipid and protein oxidation. Overall, the 20% GP/kg-diet finished lamb meat had the highest antioxidant activity and the lowest total viable bacterial counts, lipid and protein oxidation values during the shelf-life period. The 20% GP/kg DM in lamb diets, therefore, improved lamb meat shelf-life without negatively affecting sensory quality.


Asunto(s)
Dieta/veterinaria , Almacenamiento de Alimentos , Carne Roja/análisis , Vitis , Alimentación Animal/análisis , Animales , Antioxidantes/análisis , Color , Calidad de los Alimentos , Humanos , Músculo Esquelético , Oxidación-Reducción , Carne Roja/microbiología , Oveja Doméstica
9.
Animals (Basel) ; 9(7)2019 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-31323882

RESUMEN

The availability and sustainability of suitable and good quality drinking water is a global concern. Such uncertainties threaten livestock production with an attendant ripple effect on food security. Small ruminants, including sheep and goats, appear to be promising to smallholder farmers in solving this problem because of their ability to survive in water-limited areas and harsh environment when compared with large ruminants. Their small body size is also seen as an advantage, because less water will be required for proper digestion and feed utilization. Therefore, this review will provide information regarding the adaptive responses of small ruminants on thermoregulation, blood metabolites, immune status, drug pharmacokinetics, reproduction and hormonal indices during the period of water stress. Adaptable and indigenous breeds are known to be more tolerant to water stress than selected breeds. A drop in feed intake and weight reduced respiratory rate and increased concentration of blood metabolites are the general effects and/or observations that are encountered by small ruminants during the period of water stress. The concept of water tolerance either as deprivation and/or restriction of indigenous and adaptable breeds of small ruminants is gaining ground in research studies around the world. However, more research, however, seeking to explore water tolerance capacity of adaptable breeds especially in arid and water limiting areas are still needed.

10.
Poult Sci ; 98(9): 3557-3570, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-30839084

RESUMEN

This study evaluated the effects of feeding an expeller press canola meal (EPCM) supplement (20%) on the carcass, meat, and sensory quality characteristics of spent laying hens. Thirty EPCM-based and thirty conventionally (soybean based) fed Lohmann Brown-Elite spent laying hens were obtained from a commercial egg farm. Carcass, portions, physical quality, proximate composition, fatty acids, and sensory quality were determined. EPCM-fed hens had higher (P ≤ 0.05) drum yield, breast bone weights and percentages, but lower (P ≤ 0.05) thigh and breast meat yields. Conventionally fed hens had higher (P ≤ 0.05) thaw losses, skin yellowness (b*), Chroma values and breast fat content with lower (P ≤ 0.05) cooking losses, skin redness (a*) and hue angle values, as well as breast Warner-Bratzler shear force values (N) (15.43 ± 0.600 vs. 12.37 ± 0.411). Palmitic acid, stearic acid, heneicosanoic acid, palmitoleic acid, saturated fatty acids (SFA) (34.0 ± 0.56 vs. 38.7 ± 0.71), n-6:n-3 polyunsaturated fatty acids (PUFA) ratio (5.5 ± 0.13 vs. 7.2 ± 0.28), atherogenic index, thrombogenic index, delta-5 desaturase, elongase index, and thiosterase index were lower (P ≤ 0.05) for EPCM-fed hen breast meat. Myristic acid, lignoceric acid, nervonic acid, alpha-linolenic acid, docosahexaenoic acid (DHA), PUFA:SFA ratio (0.7 ± 0.05 vs. 0.9 ± 0.02), n-3 PUFA (3.4 ± 0.31 vs. 5.1 ± 0.17), hypocholesterolemic:Hypercholesterolaemic, stearoyl-CoA desaturase 16, and stearoyl-CoA desaturase 18 were higher (P ≤ 0.05) for EPCM-fed hen breast meat. Metallic flavor was decreased (P ≤ 0.05) for EPCM-fed hen breast meat. Generally, effects of EPCM supplementation were observed to have an effect on the carcass, physical quality, proximate composition, fatty acids, and health indices. The sensory profiles did not differ between EPCM and conventionally fed spent laying hen breast meat (except for metallic flavor). The EPCM improved the nutritional profile of spent laying hen meat with low intramuscular fat, low n-6:n-3 PUFA ratio, and favorable lipid health indices.


Asunto(s)
Ácidos Grasos/análisis , Calidad de los Alimentos , Carne/análisis , Aceite de Brassica napus/metabolismo , Alimentación Animal/análisis , Animales , Pollos , Dieta/veterinaria , Suplementos Dietéticos/análisis , Femenino , Aceite de Brassica napus/administración & dosificación
11.
Anim Nutr ; 5(1): 95-100, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30899816

RESUMEN

The experiment investigated the influence of forage drying methods on the dry-matter digestibility of foliage from Cajanus cajan varieties (ICEAP 00557, ICEAP 01514 and CIMMYT100/01). These leaves were harvested at week 20 of growth and either oven- or shade-dried and analysed for chemical components and rumen degradability. Three rumen fistulated lactating Holstein cows (430 ± 18 kg live weight) were used to evaluate ruminal degradation kinetics using in vitro and in sacco procedures. Samples were incubated for 0, 4, 8, 12, 24, 30 and 48 h in vitro (IV DaisyII) procedure. In the in sacco procedure, samples were incubated for 0, 4, 8, 12, 24, 30 and 48 h in the rumen of cows. Dry matter disappearance (DMD) data for both measures were fitted to the equation Y = a + b (1 - e -ct ), where b is the slowly degradable fraction and c is the degradation rate constant, to approximate rumen degradability characteristics of varieties. Shade dried leaves contained higher crude protein (CP) (P < 0.05) than oven dried leaves. Oven drying method increased (P < 0.05) neutral detergent insoluble nitrogen (NDIN) and acid detergent insoluble nitrogen (ADIN) content of varieties. However, shade drying method gave the higher concentration of NDIN and ADIN. Drying technique had no effect (P > 0.05) on ash, neutral detergent fiber (NDF), acid detergent fiber (ADF) and acid detergent lignin (ADL) of varieties. Drying method did not affect (P > 0.05) calcium (Ca) and phosphorus (P) concentration in the forage dry matter. Drying method had no effect (P > 0.05) on b and c of all varieties during in vitro procedure. However, shade-drying method increased (P < 0.05) b and c of all varieties during in sacco procedure. It was concluded that shade-drying, in contrast to oven-drying, would be the most suitable method as it improves the nutritive value of the forage for ruminants.

12.
Int J Food Sci ; 2019: 2628747, 2019.
Artículo en Inglés | MEDLINE | ID: mdl-30713849

RESUMEN

The global meat industry is characterised by a growing interest in natural preservative additives. This study determined the effect of sweet basil (Ocimum basilicum L.) essential oil (SBEO) on colour and lipid oxidation in minced beef. The phytoconstituents of SBEO were analyzed by gas chromatography mass spectrometry. Thereafter, minced beef samples from Nguni and Boran cattle were treated with either no additives (control, C) or SBEO added at 2% (SB2), 4% (SB4), or 6% (SB6). The meat samples were aerobically packaged and stored (4 ± 1°C) for seven days for measurement of lightness (L⁎), redness (a⁎), yellowness (b⁎), hue, chroma, and lipid oxidation (acid-reactive substances, TBARS) on days 0, 4, and 7. Thirty-two bioactive compounds with reported antioxidant and antimicrobial and activities were identified in SBEO, including Estragole (41.40%), 1, 6-Octadien-3-ol, 3,7-dimethyl (29.49%), and trans-.alpha.-Bergamotene (5.32%). On days 0, 4, and 7, SB2, SB4, and SB6 had higher (P < 0.05) L⁎, a⁎, b⁎, hue, and chroma values; and on days 0 and 4 TBARS were lower (P < 0.05) in SB2 and SB4 than C and SB6. The addition of 2% and 4% SBEO improved colour and lipid oxidative stability, demonstrating potential for its use as a natural antioxidant additive in meat.

13.
Vet Anim Sci ; 8: 100073, 2019 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-32734090

RESUMEN

The objective of this study was to evaluate the effects of forage legume diets on haematological and biochemical indices of Xhosa goats. Eighteen animals, one-year-old, of average live weight 14.13 ±â€¯0.24 kg were assigned, in a completely randomized design, to three treatment diets. Animals were housed individually and sex was equally represented among treatments with 6 animals per treatment. Weights and blood samples were taken every fortnight. A pair of blood samples (5 ml each) were collected from each goat, via jugular vein puncture and were subjected to either haematological or biochemical analysis. The results show that treatment diets and sex significantly (P < 0.05) affected DMI, total gain, ADG, and feed conversion ratio. Treatment diets and sex had no effects (P > 0.05) on serum total proteins, globulins, urea, creatinine, alanine aminotransferase, alkaline phosphatase (ALP), and gamma- glutamyl transferase concentrations. The diet influenced albumin was (P < 0.05) while sex influenced ALP concentration (P < 0.05). Measured over time, the plasma concentration of urea and ALP significantly increased (P < 0.05) while creatinine and cholesterol concentration decreased (P < 0.05). Although the overall blood biochemical properties remain unchanged among the treatments and between sexes; treatment by sex, treatment by day and sex by day interactions were significant (P < 0.05). The white blood cells, red blood cell, mean corpuscular haemoglobin, mean corpuscular haemoglobin concentration, haemoglobin, haematocrit, and platelet and mean platelet volume levels were similar among treatments and between sexes (P > 0.05). The mean cell volume and red cell distribution width were different among treatments (P < 0.05). Treatment diets significantly (P < 0.05) influenced neutrophil (%) content while sex influenced basophile (%) content. In conclusion forage legumes did not cause toxicity in goats or any pathological condition.

14.
Meat Sci ; 147: 6-12, 2019 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-30172086

RESUMEN

This study investigated the effects of feeding graded levels of sun-dried red grape pomace (GP; 0, 5, 10, 15 and 20%) on growth, carcass and meat physico-chemical quality attributes of Dohne Merino lambs for 42 days. Dry matter intake increased quadratically with a critical value (i.e., optimum inclusion level) of 11.3% GP (P ≤ 0.05). Diet exhibited similar quadratic responses for average daily gain, live, hot and cold carcass weights with optimum inclusion levels at 9.6, 9.7, 12, 2 and 12.1, respectively (P ≤ 0.05). Overall, meat quality traits were not negatively affected by GP inclusion (P > .05). Gross profit was influenced by diet, with an optimum inclusion level at 12.2% (quadratic; P ≤ 0.05). Overall, inclusion of 12.2% GP in lamb finishing diets at the expense of oat bran and wheat bran middlings improved lamb productivity, without compromising meat quality.


Asunto(s)
Alimentación Animal/análisis , Carne Roja/análisis , Oveja Doméstica/crecimiento & desarrollo , Vitis , Alimentación Animal/economía , Fenómenos Fisiológicos Nutricionales de los Animales , Animales , Dieta/veterinaria , Masculino , Residuos Sólidos
15.
Acta Trop ; 190: 129-136, 2019 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-30408462

RESUMEN

Salmonella enterica is a leading cause of human gastroenteritis in both developed and developing countries, causing significant economic losses on humans and animals worldwide. There are several routes for contracting salmonellosis, but the consumption of contaminated foods is by far the most frequent cause of human infections. This study aimed to assess the prevalence and resistance determinants of S. enterica isolates obtained from meat. Swab samples from meat were cultured for the identification of Salmonella spp., and 239 presumptive S. enterica isolates were recovered, purified and kept in glycerol stocks. The S. enterica. confirmed by polymerase chain reaction (PCR) were further tested against 15 antimicrobials using the disc-diffusion method on Muller-Hinton agar and the genotypic antimicrobial resistance determinants by PCR. Resistance among tetracyclines, bêta-lactams, and 3rd generation cephalosporins was found to be most frequent with a noticeable rise in the number of multi-drug resistance ranging from two to seven antimicrobials. A total of 20 resistance determinants were assessed with their prevalence and distributions obtained as follows; [aminoglycosides: aadA (89%), aacC2 (100%), aphA1 (38%), aphA2 (0%) and strA (7%)], [ß-lactams: (ampC 100%), blaTEM, (33%), blaZ (17%) and blaOXA (10%)], [Chloramphenicol: catI (9%), catII (7%), and cmIA1 (10%)] and [tetracyclines: tetA (57%), tetB (30%), tetC (11%), tetD (73%), tetK (20%) and tetM, (43%)], and [sulfonamides: sulI (82%), sulII (7%)]. The findings signify a high prevalence of multidrug-resistant (MDR) S. enterica isolates and resistance determinants indicating increased public health risks associated with the consumption of contaminated meat.


Asunto(s)
Antibacterianos/farmacología , Farmacorresistencia Bacteriana Múltiple/genética , Carne/microbiología , Salmonella enterica/efectos de los fármacos , Animales , Humanos , Pruebas de Sensibilidad Microbiana , Salmonella enterica/genética , Sudáfrica
16.
Asian-Australas J Anim Sci ; 32(5): 734-741, 2019 May.
Artículo en Inglés | MEDLINE | ID: mdl-30056671

RESUMEN

OBJECTIVE: The objective of the study was to determine the relationship between plasma and salivary cortisol concentrations in beef cattle that were subjected to handling prior to sampling. METHODS: Twenty-one Nguni cows of three age categories; 5 to 7 yr (n = 7), 8 to 10 yr (n = 6), and 11 to 13 yr (n = 8) were handled for five consecutive weeks. In the pen, a human avoidance test was performed and cattle responses to restraint in the chute and crush were observed. In addition, rectal temperature readings were taken and, faecal samples were collected and analysed for glucocorticoid metabolites. Through the handling and restraint process, excretory and vocalisation behaviour, as a sign of stress were observed and recorded. Thereafter, six cows were randomly selected and subjected to an adrenocorticotropic hormone (ACTH) challenge. Blood and saliva samples were extracted to determine cortisol concentrations. RESULTS: Repeated handling affected (p<0.05) faecal glucocorticoid metabolites, rectal temperatures, avoidance distance, crush scores as well as urination and defaecation behaviour. Acclimation to handling was variable based on each respective parameter. Saliva cortisol concentrations increased and decreased significantly (p<0.001). A peak value of 136.78± 15.869 nmol/L was observed 30min after administration of ACTH, from a baseline value of 8.75± 15.869 nmol/L. Plasma cortisol concentrations did not differ (p>0.05) across the time of sampling. A low and insignificant correlation (r = 0.0131, p>0.05) between plasma and saliva cortisol was therefore observed. CONCLUSION: We conclude that if beef cows are subjected to handling prior to sampling, a weak relationship exists between plasma and salivary cortisol levels.

17.
J Food Sci Technol ; 55(12): 4833-4840, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30482978

RESUMEN

Droëwors are traditional South African salted and dried sausages, made without nitrites/nitrates and non- fermented. Different meat sources (beef, game and ostrich) are traditionally used in droëwors processing, while the use of pork is uncommon, as it is said to lead to rancidity. The first part of the study analysed the physico-chemical composition of commercially available beef, game and ostrich meat droëwors (n = 20). On average, they were composed of 26.3-29.2 g/100 g moisture, 41.3-44.0 g/100 g protein, 26.2-33.1 g/100 g fat and 5.9-6.5 g/100 g ash and 5.0-5.4 pH. Water activity (0.76-0.82) was sufficiently low to ensure shelf stability at ambient temperatures. In the second part beef and pork droëwors were formulated in accordance with these results and with similar fat content, dried for 2 days (30 °C, 40% relative humidity) and stored for 26 days (25 °C, 50% relative humidity); measuring moisture, water activity, pH and lipid oxidative stability (thiobarbituric acid reactive substances (TBARS)) weekly. At day 5, moisture and thus water activity of pork droëwors was slightly higher compared to beef ones and fat and ash content slightly lower (P ≤ 0.05) despite similar weight loss. Even with slightly less fat, TBARS in pork droëwors were significantly higher after drying and throughout storage (3.83 vs 0.99 mg MDA equivalents/kg dry matter at a maximum).

18.
Food Res Int ; 112: 400-411, 2018 10.
Artículo en Inglés | MEDLINE | ID: mdl-30131152

RESUMEN

The effect of the addition of seaweed extracts from three brown algae species [Ascophyllum nodosum (AN), Fucus vesiculosus (FV) and Bifurcaria bifurcata (BB)], which are a great source of natural antioxidants, on the oxidative stability of refrigerated low-fat pork liver pâtés was studied. In the studied pâtés, half of pork fat was replaced with a mixture consisting of canola and high-oleic sunflower oil (75:25, v/v), thus improving their fatty acid profile in terms of polyunsaturated fatty acids (PUFA). In order to avoid the oxidation of PUFA in the new samples, seaweed extracts (500 ppm) were added. In addition, some samples were formulated with a synthetic antioxidant (BHT at 50 ppm) (BHT) and a control batch (CON) (without antioxidant) was also prepared, for comparison purposes. Thus, in total, five batches of liver pâté were prepared: CON, BHT, AN, FV and BB. Pâté samples were analyzed at 0, 45, 90, 135 and 180 days of refrigerated storage at 4 °C. The addition of seaweed extracts did not modify significantly (P > 0.05) the chemical composition or microbial characteristics of healthy pork liver pâté, except for the protein content, which resulted in a significant increase (≈2-3%) in the batches manufactured with addition of seaweed extracts compared to control samples. At the end of storage (180 days), L* values were significantly lower in the FV and BB batches than in the other batches. Moreover, the a* and b* values were also significantly lower in CON batches than in the samples with antioxidants added. Differences in oxidative parameters (conjugated dienes, TBARs and carbonyls) among batches were observed at the end of the storage time, showing samples with seaweed extracts a similar degree of protection against oxidation compared to BHT formulated samples. A decline of the volatile compounds was noted in all the batches during storage. The total volatile compounds at the end of the storage were significantly lower in BTH, AN, or BB batches than in control batches.


Asunto(s)
Antioxidantes/química , Ascophyllum/química , Conservación de Alimentos/métodos , Conservantes de Alimentos/química , Fucus/química , Productos de la Carne/análisis , Carne Roja/análisis , Algas Marinas/química , Animales , Antioxidantes/aislamiento & purificación , Dieta con Restricción de Grasas , Microbiología de Alimentos/métodos , Conservantes de Alimentos/aislamiento & purificación , Productos de la Carne/microbiología , Valor Nutritivo , Oxidación-Reducción , Aceite de Brassica napus/química , Carne Roja/microbiología , Refrigeración , Aceite de Girasol/química , Sus scrofa , Factores de Tiempo , Compuestos Orgánicos Volátiles/análisis
19.
Meat Sci ; 146: 87-92, 2018 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-30138886

RESUMEN

Drying kinetics and changes in proximate composition, pH, salt content, water activity (aw) and lipid oxidation through processing of salami made using five different game meat species were evaluated and compared to pork. Eight batches of salami from each species were made and sampled for analysis throughout processing. Processing time was a significant factor on all measured attributes whilst species affected (P ≤ .05) pH and moisture but not drying kinetics. Black wildebeest meat exhibited higher (P ≤ .05) pH than pork and other game meat (6.30 vs 5.63-5.80), which translated to higher (P ≤ .05) salami pH throughout and at the end of processing (5.77). Final pH of all other salami ranged from 5.01 to 5.28, aw ranged from 0.88 to 0.92. TBARS remained lower than 1 mg MDA equivalent/kg. The study suggests that salami from these game species, excluding black wildebeest, can be produced using the same processing parameters as conventional pork salami and obtaining similar physico-chemical attributes.


Asunto(s)
Manipulación de Alimentos/métodos , Productos de la Carne/análisis , Animales , Fermentación , Concentración de Iones de Hidrógeno , Rumiantes , Porcinos , Sustancias Reactivas al Ácido Tiobarbitúrico/análisis , Factores de Tiempo , Agua/química
20.
Food Res Int ; 111: 379-390, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-30007699

RESUMEN

Oxidative damage is one of the main reasons for loss of quality in sheep and goat meat and meat products. Synthetic antioxidants are the current solution to stabilize oxidative process and extend the shelf life of such products; however, the negative impact on health may impose a risk to consumers. Natural antioxidants, extracted from several vegetable sources, have been considered an attractive alternative for this conflicting situation. Phenolic compounds are minor components in herbs, spices, tea and fruits that display potential application against the progression of lipid and protein oxidation and their consequences for meat quality, which can even overcome the protective effect of synthetic compounds. This review aims to discuss the mechanisms associated to lipid and protein oxidation and their implications on meat quality attributes and provides recent data regarding the application of natural antioxidants in sheep and goat meat products, which have a high susceptibility to oxidative processes compared to other red meats.


Asunto(s)
Antioxidantes/farmacología , Conservación de Alimentos/métodos , Calidad de los Alimentos , Almacenamiento de Alimentos/métodos , Productos de la Carne/análisis , Extractos Vegetales/farmacología , Animales , Cabras , Peroxidación de Lípido , Oxidación-Reducción , Ovinos , Verduras
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