Non-destructive prediction of fertility and sex in chicken eggs using the short wave near-infrared region

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.

The ability of a portable near infrared instrument to evaluate the shelf-life of fresh and thawed goat muscles

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.

The Effect of Sex on the Chemical and Mineral Composition of the Meat, Bone and Liver of Giraffe (Giraffa giraffa angolensis)

Consumers tend to buy meat based on visual physical characteristics, which are affected by the chemical composition of the meat, and there is very little known about the chemical composition of the meat of giraffe. This study therefore aims to broaden the knowledge base on the chemical composition of giraffe meat, rib bone and liver. Eight different muscles from 15 giraffes were analyzed to determine the chemical composition, yielding an average moisture of 77.2 ± 0.09 g/100 g meat, an average protein of 20.8 ± 0.09 g/100 g meat, an average intramuscular fat (IMF) of 1.4 ± 0.03 g/100 g meat and an average ash of 1.1 ± 0.01 g/100 g meat. There was a significant interaction between sex and muscle for the moisture, protein and ash contents, while only muscle had an effect on the fat content. The mineral content of the bone, liver and Longissimus thoracis et lumborum muscle was also analyzed, and bone was found to be a rich source of calcium (highest concentration), whilst the liver had the highest concentration of iron. The chemical composition of the giraffe meat was such that it could be classified as lean meat.

Predicting Egg Storage Time with a Portable Near-Infrared Instrument: Effects of Temperature and Production System

Determining egg freshness is critical for ensuring food safety and security and as such, different methods have been evaluated and implemented to accurately measure and predict it. In this study, a portable near-infrared (NIR) instrument combined with chemometrics was used to monitor and predict the storage time of eggs under two storage conditions-room temperature (RT) and cold (CT) storage-from two production systems: cage and free-range. A total of 700 egg samples were analyzed, using principal component analysis (PCA) and partial least squares (PLS) regression to analyze the NIR spectra. The PCA score plot did not show any clear separation between egg samples from the two production systems; however, some egg samples were grouped according to storage conditions. The cross-validation statistics for predicting storage time were as follows: for cage and RT eggs, the coefficient of determination in cross validation (R2CV) was 0.67, with a standard error in cross-validation (SECV) of 7.64 days and residual predictive deviation (RPD) of 1.8; for CT cage eggs, R2CV of 0.84, SECV of 5.38 days and RPD of 3.2; for CT free-range eggs, R2CV of 0.83, SECV of 5.52 days and RPD of 3.2; and for RT free-range eggs, R2CV of 0.82, SECV of 5.61 days, and RPD of 3.0. This study demonstrated that NIR spectroscopy can predict storage time non-destructively in intact egg samples. Even though the results of the present study are promising, further research is still needed to further extend these results to other production systems, as well as to explore the potential of this technique to predict other egg quality parameters associated with freshness.

The Status of Marine Mussel Pollution Research in South Africa (2012-2022)

The growing human population requires more food each year, and seafood products can help meet this demand if clean water resources are available for their growth. Farmed and wild mussels are environmentally friendly seafood with many health benefits to human consumers, but they can also pose a health risk if they are harvested from areas where marine anthropogenic pollution is uncontrolled or unmonitored. While the coastline in South Africa has long been assumed to be pristine, a growing number of recent studies are raising contamination concerns. Baseline studies establish a wide range of anthropogenic pollutants to be present in the marine environment, specifically in urbanised or industrialised areas like major cities or harbours. This review summarises how mussels could pose health risks to human consumers and the current research that is being conducted by private researchers and institutions in South Africa. The review emphasises the need for more research in the field and for governmental pollution monitoring data to be released to the public.

Basic Hazard Control Plan for Small Wild Ungulates Slaughtered for Meat Production

Animal slaughter plans and related activities must not increase the number of hazards in meat. In their nature, these processes must reduce possible hazards to minimum or acceptable levels. This is a generally accepted concept worldwide; hence, authorities continue to develop regulations that seek to mitigate the scourge of meat hazards for consumer protection. The situation is similar with small wild ungulate meat, in which a hazard analysis plan needs developing to improve meat safety. This investigation follows a narrative review of articles published for a PhD program and other scholarly articles supporting the concept of a basic slaughter plan for small wild ungulate animals in South Africa. The findings of this investigation highlight the need to control hazards within one health concept plan, which should be implemented and propagated by establishing forums that will drive meat safety solutions in these communities. There should be a basic hygiene slaughter plan developed and endorsed by all members of the forum. The outcome must be the control of microbiological, chemical and physical hazards from farm-to-fork, and as part of a system imbedded in game meat policies and regulations.

Carcass and Offal Yields of Farmed Common Eland (Taurotragus oryx) Males, as Affected by Age and Immunocastration

This study investigated the effects of immunocastration and slaughter age on the carcass yield performance of intensively farmed common eland males. Eighteen male eland (five immunocastrated juveniles, three intact juveniles, five immunocastrated sub-adults, and five intact sub-adults) were finished for four months, after which their carcass, offal, primal cut, and individual muscle yields were determined. Juveniles were ~6 months of age at the start of the experiment, while sub-adults were ~1.5 years old. Primal cuts were dissected to determine the percentage yields of meat, bones (with tendons), separable fat, and trimmings. Immunocastration had no effect on offal or carcass yields. While sub-adults had increased individual muscle yields, juveniles had greater proportionate yields of primal cuts and a greater total high-value: low-value meat ratio. Whilst slaughtering younger male eland could provide additional economic advantages, this should be considered being against changing marketing trends.

Unscrambling the Provenance of Eggs by Combining Chemometrics and Near-Infrared Reflectance Spectroscopy

Issues related to food authenticity, traceability, and fraud have increased in recent decades as a consequence of the deliberate and intentional substitution, addition, tampering, or misrepresentation of food ingredients, where false or misleading statements are made about a product for economic gains. This study aimed to evaluate the ability of a portable NIR instrument to classify egg samples sourced from different provenances or production systems (e.g., cage and free-range) in Australia. Whole egg samples (n: 100) were purchased from local supermarkets where the label in each of the packages was used as identification of the layers’ feeding system as per the Australian legislation and standards. The spectra of the albumin and yolk were collected using a portable NIR spectrophotometer (950–1600 nm). Principal component analysis (PCA) and linear discriminant analysis (LDA) were used to analyze the NIR data. The results obtained in this study showed how the combination of chemometrics and NIR spectroscopy allowed for the classification of egg albumin and yolk samples according to the system of production (cage and free range). The proposed method is simple, fast, environmentally friendly and avoids laborious sample pre-treatment, and is expected to become an alternative to commonly used techniques for egg quality assessment.

Rice Bran Makes a Healthy and Tasty Traditional Indonesian Goat Meatball, 'Bakso'

Meatballs are popular in Asia and traditionally made from beef or chicken with tapioca (≈8% wt/wt) as filler. Tapioca has a high glycaemic index (GI); therefore, rice bran was evaluated as a substitute to create a healthier meatball of acceptable quality. Substitution of tapioca with rice bran (100:0; 75:25, 50:50; 25:75; 0:100% tapioca: % rice bran) decreased the starch content (7.8 to 3.3%) and GI (56.08 to 43.85) whilst increasing the protein (10.9 to 12.8%) and fibre (8.1 to 10.3%) contents. Although consistency (995 to 776 N/mm) was affected, firmness (90.6 to 90.5 N) and shear force (300 to 312 N) were only slightly affected by the ratio of tapioca to rice bran. Sensory analysis revealed that the goat meatball with the substitution of tapioca with up to 25% rice bran was deemed acceptable by 40 Indonesian consumers.

Escherichia coli Antibiotic Resistance Patterns from Co-Grazing and Non-Co-Grazing Livestock and Wildlife Species from Two Farms in the Western Cape, South Africa

Although limited, studies have found conflicting results on whether co-grazing results in significant antibiotic resistance transfer between species. This type of farming system can act as a vector in the geographical spread of antibiotic-resistant bacteria in the environment. The aim of this study was to determine the antibiotic-resistant patterns between co-grazing and non-co-grazing livestock and wildlife species in South Africa. Escherichia coli was isolated from the faeces of various wildlife and livestock species from two farms in South Africa and was tested for antibiotic resistance using the Kirby–Bauer disk diffusion method against chloramphenicol, nalidixic acid, ampicillin, streptomycin, sulphafurazole, and tetracycline. A selection of some common antibiotic-resistant genes (blaCMY, aadA1, sul1, sul2, tetA, and tetB) were detected using PCR. The E. coli isolates from wildlife and livestock that co-grazed showed no significant differences in antibiotic resistance patterns. However, this was not the case for tetracycline resistance as the livestock isolates were significantly more resistant than the co-grazing wildlife isolates. The E. coli isolates from the non-co-grazing livestock and wildlife had significant differences in their antibiotic susceptibility patterns; the wildlife E. coli isolates were significantly more resistant to sulphafurazole and streptomycin than the livestock isolates, whilst those isolated from the cattle were significantly more resistant to ampicillin than the wildlife and sheep isolates. The results of this study suggest that there could be an exchange of antibiotic-resistant bacteria and genes between livestock and wildlife that co-graze.

A Preliminary Study: Antibiotic Resistance of Escherichia coli and Staphylococcus aureus from the Meat and Feces of Various South African Wildlife Species

This study determined the antibiotic resistance patterns of Escherichia coli and Staphylococcus aureus from the raw meat and feces of three game species from three different farms across South Africa. The Kirby-Bauer disk diffusion method was used according to the Clinical and Laboratory Standards Institute 2018 guidelines. E. coli was tested against ampicillin, ceftazidime, chloramphenicol, streptomycin, sulphafurazole and tetracycline. S. aureus was tested against tetracycline, erthromycin, vancomycin, penicillin, oxacillin and cefoxitin. There were no significant differences in the E. coli antibiotic resistance profiles between the meat and fecal samples (except towards ceftazidime where 5% of the meat isolates were resistant and 0% of the fecal isolates). The S. aureus meat isolates showed high (75%) resistance towards penicillin and on average, 13% were resistant to oxacillin/ cefoxitin, indicating methicillin resistance. The results from this study indicate that there is incidence of antibiotic resistant bacteria from the feces and meat of wildlife species across South Africa, suggesting that cross contamination of the meat occurred during slaughter by antibiotic resistant bacteria from the abattoir personnel or equipment and or from carcass fecal matter. In addition, the results highlight the importance of food safety and hygiene procedures during slaughter to prevent cross-contamination of antibiotic resistant bacteria, as well as pathogens, onto raw meat.

Putting the Spring back into the Hare (Pedetes capensis): Meat Chemical Composition of an Underutilized Protein Source

Alternative protein sources are gaining increasing global attention as a solution to address future protein demands. Determining the chemical composition of meat alternatives is vital to confirm that it is nutritious, but also to increase product value and promote its utilization. The carcass characteristics and chemical composition of springhare, an underutilized protein source, was found to be comparable to that of commercially reared rabbits. Hence, its introduction into the commercial supply chain would likely not offset consumers accustomed to purchasing rabbit/hare meat. Springhare meat had a high protein content (~22.5 g/100 g meat) and low lipid (<1.3 g/100 g meat) content. The meat's fatty acids mainly comprised C18:2n6c (γ-linoleic acid; 24%), C18:0 (stearic acid; 20%), C16:0 (palmitic acid; 19%), C20:4n6 (arachidonic acid; 15%) and C18:1n9c (oleic acid; 13%). Although sex did not significantly influence the carcass characteristics and meat composition, season did have an effect (p < 0.05) on the fatty acid profile. The meat harvested in summer had higher (p < 0.05) concentrations of favorable unsaturated fatty acids, C18:2n6c, C18:3n6, C18:3n3 (α-linolenic acid), C20:2n6 (eicosadienoic acid), C20:3n3 (eicosatrienoic acid), compared to the meat obtained in winter, which contained more (p < 0.05) saturated fatty acids. The results verify that springhare can be utilized as a viable alternative protein source.

The Effects of Production System and Sex on the Sensory Quality Characteristics of Dorper Lamb

The effect of production systems on the sensory quality characteristics of Dorper lambs was investigated. Sixty lambs (ewes, rams, castrates) were allocated into two production groups (feedlot or free-range) at weaning with equal numbers of each sex represented in each group. The lambs were fed for five (slaughter group 1) or six (slaughter group 2) weeks. Feedlot lambs were fed a commercial pelleted diet while free-range lambs utilized natural shrub pastures. Samples of the Longissimus thoracis muscle were used for sensory evaluation. Feedlot lambs produced meat that was juicier and more tender than meat from free-range lambs. Initial juiciness was also higher in the meat from the feedlot lambs. No aroma or flavour differences were observed. The meat from the free-range ram lambs (slaughter group 1) was the least tender, whereas the lamb flavour was also compromised in the free-range ram lambs. Free-range meat may not necessarily be distinguished from feedlot meat as far as aroma and flavour are concerned.

Slaughter Characteristics of Feedlot-Finished Premium South African Lamb: Effects of Sex and Breed Type

This study compared the carcass characteristics of ram and ewe lambs from South African wool, dual-purpose, meat, and fat-tailed sheep types, reared to produce premium lamb carcasses. The lambs were reared on a feedlot diet (10.41 MJ ME/kg feed and 19.06% crude protein) from weaning (30 kg live weight) until they attained a back-fat depth of ~4 mm, measured using ultrasound. After slaughter, the carcasses were assessed for retail cut yields, composition, and physical meat quality. Later, maturing lambs attained heavier carcass weights than early maturing breeds (~20.7 kg vs. 16.9 kg, respectively; p ≤ 0.05), and differences in carcass composition and retail cut yields were ascribed to differences in the frame size and pattern of fat deposition of the respective breeds. Small differences in physical meat quality were observed, with meat from Dormer and Namaqua lambs having notably higher shear-force values (~46 N) than that from Meatmaster carcasses (~34 N). These differences though are expected to have little influence on the perceived quality of the meat.

Effects of honeybush (Cyclopia subternata) extract on physico-chemical, oxidative and sensory traits of typical Italian salami

Honeybush (Cyclopia subternata Vogel) is an indigenous South African shrub enjoyed as hot brewed tea. "Unfermented" honeybush is also a potential antioxidant bioactive extract for foodstuffs due to its polyphenol content. The effect of "unfermented" honeybush extract (Hob; 0.5%) was evaluated in typical Italian salami and compared with nitrate (Nit; 100 mg/kg) and a control (Ctl; without nitrate or honeybush). After 35 days of ripening, Hob had a higher (p < .01) water activity (0.928), compared with Ctl (0.923) and Nit (0.924). Final pH (5.35-5.24) was not affected by treatments. Lower lipid oxidation was observed in Hob and Nit treatments (p < .001) compared with Ctl. Internal color and odor intensity were similar among treatments. Salami with honeybush extract had less spontaneous outer surface mold growth whereas the Ctl showed intermediate growth (p < .05). Honeybush extract seems a promising natural ingredient with antioxidant action.

A Preliminary Study: Antibiotic Resistance Patterns of Escherichia coli and Enterococcus Species from Wildlife Species Subjected to Supplementary Feeding on Various South African Farms

Simple Summary

Supplementary feeding of wildlife allows more opportunity for disease and antibiotic resistant genes to be transferred directly between species due to increased herd density, more frequent direct contact at feeding and water points and increased human contact. The feed itself can also be a direct source of antibiotic compounds and of antibiotic resistant bacteria. This study aimed to determine whether the practice of wildlife supplementary feeding could have an influence on the antibiotic resistance of the bacteria harboured by the supplementary fed wildlife, and thus play a potential role in the dissemination of antibiotic resistance throughout nature. Overall, the E. coli and Enterococcus isolates from the supplementary fed wildlife were found to be more frequently resistant to the selection of antibiotics than from those which were not supplementary fed. Game farmers should be knowledgeable of the ingredients that are used in the game feed that is used to feed both their livestock and wildlife, as certain feed ingredients, such as antibiotics or bone meal, can have a detrimental effect on health and safety. Game farmers should also be aware that farm history can have an impact on the animals which graze on the pastures with regards to antibiotic resistance transfer.

Abstract

Studies have shown that antibiotic resistance among wild animals is becoming a public health concern, owing to increased contact and co-habitation with domestic animals that, in turn, results in increased human contact, indirectly and directly. This type of farming practice intensifies the likelihood of antibiotic resistant traits in microorganisms transferring between ecosystems which are linked via various transfer vectors, such as rivers and birds. This study aimed to determine whether the practice of wildlife supplementary feeding could have an influence on the antibiotic resistance of the bacteria harboured by the supplementary fed wildlife, and thus play a potential role in the dissemination of antibiotic resistance throughout nature. Escherichia coli and Enterococcus were isolated from the faeces of various wildlife species from seven different farms across South Africa. The Kirby-Bauer disk diffusion method was used according to the Clinical and Laboratory Standards Institute 2018 guidelines. The E. coli (F: 57%; N = 75% susceptible) and Enterococcus (F: 67%; N = 78% susceptible) isolates from the supplementary fed (F) wildlife were in general, found to be more frequently resistant to the selection of antibiotics than from those which were not supplementary fed (N), particularly towards tetracycline (E. coli F: 56%; N: 71%/Enterococcus F: 53%; N: 89% susceptible), ampicillin (F: 82%; N = 95% susceptible) and sulphafurazole (F: 68%; N = 98% susceptible). Interestingly, high resistance towards streptomycin was observed in the bacteria from both the supplementary fed (7% susceptible) and non-supplementary fed (6% susceptible) wildlife isolates. No resistance was found towards chloramphenicol and ceftazidime.

Hermetia illucens Larvae Reared on Different Substrates in Broiler Quail Diets: Effect on Physicochemical and Sensory Quality of the Quail Meat

This research aimed at improving the fatty acid (FA) profile of Hermetia illucens larvae (HI) and evaluating the effects of their inclusion in growing broiler quails' diets on the meat physicochemical quality, including detailed amino acid (AA) and FA profiles, sensory traits, and retail display. HI larvae were reared on two different substrates: layer mash (HI1) and 50:50 layer mash/fish offal (HI2). A total of 300 10-day-old quails were allocated to the three dietary groups (five replicates/each): a soybean meal-based diet was formulated (Control), and two other diets were formulated that included either 10% HI1 or HI2. Quails were fed the experimental diets until slaughter. Diets were formulated to be isonitrogenous and isoenergetic. Breast meat quality was affected by the dietary treatments, which displayed different proximate compositions and AA and FA profiles. Meat physical quality, sensory profile, and retail display remained unaffected for the most part. Overall, results showed that it is possible to improve the FA profile of the HI-fed quails' meat and thus lipid quality through substrate modulation of the HI's diet.

Monitoring of trace metal accumulation in two South African farmed mussel species, Mytilus galloprovincialis and Choromytilus meridionalis

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.

Profile of cabanossi made with exotic meats and olive oil

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.

Effect of sex and time to slaughter (transportation and lairage duration) on the levels of cortisol, creatine kinase and subsequent relationship with pork quality

The study determined the effect of sex and time to slaughter on cortisol and creatine kinase levels, and pork quality in commercial crossbred pigs. Saliva samples were before collected transportation, on arrival at the abattoir, and after a 20 hour lairage period. Cortisol levels from saliva (SC), serum (SeC) and urine (UC) were determined. Creatine kinase (CK) levels were determined from serum samples. Fifteen boars vs. 15 gilts were immediately slaughtered on arrival (SOA), and the other 15 boars vs. 15 gilts were rested for 20 h before slaughter. Meat quality parameters were also determined. In both sexes, SC significantly increased in response to time to slaughter. There was a significant interaction of sex and time to slaughter on SeC. Gilts had higher CK levels and lower muscle L* values than boars. There were correlations among baseline SC, SeC, UC and most meat quality parameters. Time to slaughter influenced levels of SC, UC, CK and pork quality between boars and gilts.

Physical meat quality and chemical composition of the Longissimus thoracis of entire and immunocastrated pigs fed varying dietary protein levels with and without ractopamine hydrochloride

Physical and chemical attributes of the Longissimus thoracis (LT) of 96 PIC(©) entire (E) and immunocastrated (C) pigs were evaluated. The study followed a 2 × 2 × 3 factorial design where three diets of low, medium and high proteins (7.50, 9.79 and 12.07 g digestible lysine/kg) were fed either with (10mg/kg) or without ractopamine (RAC) for the last 28 days of growth. Vaccination of C occurred at 16 and 20 weeks and slaughtering at 24 weeks of age. The LTs were analysed for moisture, protein, fat and ash contents as well as CIE L*, a*, b* colour, drip loss, cooking loss and Warner-Bratzler shear force (WBSF). Various sex and protein interactions were observed for LT protein content, L* values and WBSF. Cooking loss was decreased in C and by the medium protein diet. Feeding RAC increased WBSF values, whilst decreasing a* and b* values. However, the differences observed are minor and might be considered negligible when evaluated by a consumer.