South African Journal of Animal Science最新文献_第5页

Performance and meat quality of broiler chickens fed diets containing hydroethanolic extract of guavira seed or peel 番石榴籽或果皮氢乙醇提取物对肉鸡生产性能和肉品质的影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v52i5.14

P. O. Nesello, C. Eyng, R. Nunes, E. Argandoña, C. Correia, J. Broch, N. Rohloff Junior, V. Savaris, E. C. dos Santos

{"title":"Performance and meat quality of broiler chickens fed diets containing hydroethanolic extract of guavira seed or peel","authors":"P. O. Nesello, C. Eyng, R. Nunes, E. Argandoña, C. Correia, J. Broch, N. Rohloff Junior, V. Savaris, E. C. dos Santos","doi":"10.4314/sajas.v52i5.14","DOIUrl":"https://doi.org/10.4314/sajas.v52i5.14","url":null,"abstract":"The dietary inclusion of hydroethanolic extract of guavira seed or peel was evaluated on broiler performance, intestinal morphometry, carcass yield, and meat quality. A total of 1,680 male chicks, one day old, were distributed in a 2×5+2 factorial design (hydroethanolic extract of guavira seed (HEGS) or hydroethanolic extract of guavira peel (HEGP); 100; 200; 300; 400 and 500 mg/kg of inclusion and a positive control (PC) with antibiotics and negative control (NC) without growth promoter), with seven replicates and 20 birds each. A better feed conversion ratio (FCR) was observed from days 1–7 and days 1–21 on the PC diet than on the NC diet. FCR from 1–7d of broilers on PC was better than those on HEGS or HEGP, and this better FCR was maintained until 21 d for the HEGS treatment. The HEGP diet showed lower average feed intake and better FCR for the total period compared to NC diets. Higher carcass yield and a higher L15 value for breast meat was observed in the HEGP group compared to HEGS. Broilers fed the PC diet showed a higher a* value 15 min and 24 h postmortem, higher water retention capacity in breast meat compared to birds fed HEGS, and a higher value of a* 24 h postmortem than those receiving NC. The inclusion of 100 to 500 mg/kg of HEGP or HEGS did not improve performance, intestinal morphometry, and carcass characteristics when compared to the performance-enhancing antibiotic. However, the HEGP diet provided better performance of broilers than the non-use of growth promoter additives in the diet.","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"25 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90121595","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of far infrared ray illumination on the performance, blood biochemistry, and faecal microflora of laying hens at different production stages 远红外线照射对不同生产阶段蛋鸡生产性能、血液生化及粪便微生物群的影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v53i1.08

C. Lim, H. Kim, A. You, K. N. Heo, H. Choo

{"title":"Effects of far infrared ray illumination on the performance, blood biochemistry, and faecal microflora of laying hens at different production stages","authors":"C. Lim, H. Kim, A. You, K. N. Heo, H. Choo","doi":"10.4314/sajas.v53i1.08","DOIUrl":"https://doi.org/10.4314/sajas.v53i1.08","url":null,"abstract":"This study investigated the effect of far-infrared ray (FIR) illumination on performance, blood biochemistry, and faecal microflora of laying hens at different production stages. A total of 360 Hy-line brown laying hens were randomly allocated in a 2 × 2 factorial arrangement with six replicates. Hens were distributed in two production stages (30–39 and 45–54 weeks-old). Each group was exposed to two light types (light emitting diode; LED and LED+FIR) in separate rooms. The LED treatment illuminated a wavelength of 650 ± 10 nm (0.65 ± 0.01 μm), while LED+FIR treatment emitted 15 ± 10 μm with an LED wavelength. The results showed an interaction between egg production stages and light types on the serum triglyceride concentration. The hens exposed to the LED+FIR and LED treatments showed similar egg production, feed intake, egg weight, feed conversion ratio (FCR), as well as albumen height, haugh unit, and shell thickness of eggs. LED+FIR substantially decreased the concentration of serum cholesterol (CHOL), HDL cholesterol (HDLC), and triglyceride (TG) compared to LED lighting. LED+FIR substantially reduced the number of total microbes, Escherichia coli, and Salmonella in faeces compared to birds exposed to LED light. These findings suggest that LED+FIR lights may improve hen health and the hen house environment.","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"80 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90284823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Comparative energy value of cooked grease recovered from rinse-trap water lines used as dietary fat source for feedlot lambs 从冲洗疏水管道回收的熟油脂作为饲粮脂肪源的比较能值

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v52i5.12

A. Estrada-Angulo, J. Ramos-Méndez, J. D. Urías-Estrada, B. I. Castro-Pérez, A. Barreras, R. Zinn, L. Corona, X. Perea-Domínguez, I. G. Martínez-Alvarez, Alejandro Plascencia

{"title":"Comparative energy value of cooked grease recovered from rinse-trap water lines used as dietary fat source for feedlot lambs","authors":"A. Estrada-Angulo, J. Ramos-Méndez, J. D. Urías-Estrada, B. I. Castro-Pérez, A. Barreras, R. Zinn, L. Corona, X. Perea-Domínguez, I. G. Martínez-Alvarez, Alejandro Plascencia","doi":"10.4314/sajas.v52i5.12","DOIUrl":"https://doi.org/10.4314/sajas.v52i5.12","url":null,"abstract":"The objective of this experiment was to compare the effects of dietary supplementation with cooking grease recovered from rinse-trap water lines (rinse-trap grease; RTG) versus conventional supplemental fats (tallow; TL, and yellow grease; YG) on 84-d growth performance, dietary energy, and carcass traits of feedlot lambs. Forty-eight Pelibuey × Katahdin lambs (27.7 ± 3.4 kg) were assigned in a randomized complete block design to evaluate: 1) basal diet without supplemental fat (Control); 2) 4% TL; 3) 4% YG, and 4) 4% RTG. Supplemental fats replaced maize in the control diet. Rinse-trap grease contained greater moisture (16.5 vs 0.92%) and impurities (3.6 vs 0.56%), and less total fatty acid (64.90 vs 89.60%) than that of conventional fats (TL and YG). Daily weight gain and gain efficiency were similar for control and RTG supplemental lambs, whereas ADG and gain efficiency were greater for lambs fed conventional fats than control or RTG-supplemented lambs. Both dietary net energy (NE) as well as ratio of observed-to-expected dietary NE were 4% greater for lambs supplemented with conventional fats vs RTG. Supplemental fat increased fat deposition but did not affect any other carcass measures or non-fat visceral mass. Estimated NE value for RTG was 57% of the average NE value (6.11 Mcal/kg) of tested conventional fats. Supplementation with RTG does not affect diet acceptability, and accordingly, is a suitable energy source for feedlot lambs. However, due to its lower total fatty acid content, its energy value is much lower than conventional supplemental fats.","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"33 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83943731","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Performance and egg quality of light laying hens fed with canthaxanthin and marigold flower extract 角黄素和金盏花提取物对轻型蛋鸡生产性能和蛋品质的影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v52i4.03

K. M. Maia, D. Grieser, A. Ton, D. R. Aquino, M. F. Paulino, J. Toledo, S. Marcato

{"title":"Performance and egg quality of light laying hens fed with canthaxanthin and marigold flower extract","authors":"K. M. Maia, D. Grieser, A. Ton, D. R. Aquino, M. F. Paulino, J. Toledo, S. Marcato","doi":"10.4314/sajas.v52i4.03","DOIUrl":"https://doi.org/10.4314/sajas.v52i4.03","url":null,"abstract":"The aim of this study was to determine the best level of inclusion of natural (marigold flower extract) and synthetic (canthaxanthin) pigments in the diet of light laying hens from 75 to 85 weeks old in terms of effects on performance, egg quality, and economic viability of production. A total of 288 laying hens were used in a completely randomized design, with a 4 x 4 factorial arrangement, with four levels of marigold flower extract (2.10; 2.40; 2.70; 3.00 ppm) and four of canthaxanthin (0. 40; 0.70; 1.00; 1.30 ppm), with three replications and six hens per experimental unit. The feed conversion by mass of eggs, egg mass, and egg laying rate showed linear improvement with the inclusion of canthaxanthin. The yolk index showed a quadratic effect with the inclusion of marigold and canthaxanthin, presenting a better estimate with diets containing 2.60 ppm/kg of marigold feed and 0.95 ppm/kg of canthaxanthin feed. The percentage of yolk and the Haugh unit increased linearly with the rising levels of marigold, whereas the percentage of albumen decreased linearly. In the evaluation of the YolkFan DSM® and the redness/yellowness, chroma (a*) presented a quadratic effect for the inclusion of marigold (2.73 and 2.80 ppm/kg of feed) and linear increase with canthaxanthin. It was concluded that the best yolk index was with 2.60 ppm/kg marigold flower extract and 0.95 ppm/kg canthaxanthin in the diet of light laying hens from 75 to 85 weeks old.","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"8 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81681394","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2

The effect of pre-slaughter electrical stunning on bleeding efficiency, meat quality, histology, and microbial count of several goat muscles 宰前电休克对几种山羊肌肉出血效率、肉质、组织学和微生物数量的影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v52i5.07

I. Al-Amri, I. Kadim, A. Alkindi, Q. Haq, D. Al-Ajmi, A. Haemd, R. Quibol, R. Al-Magbali, S. Khalaf, K. Hosni

{"title":"The effect of pre-slaughter electrical stunning on bleeding efficiency, meat quality, histology, and microbial count of several goat muscles","authors":"I. Al-Amri, I. Kadim, A. Alkindi, Q. Haq, D. Al-Ajmi, A. Haemd, R. Quibol, R. Al-Magbali, S. Khalaf, K. Hosni","doi":"10.4314/sajas.v52i5.07","DOIUrl":"https://doi.org/10.4314/sajas.v52i5.07","url":null,"abstract":"This study was designed to compare the effect of non-electrical stunning and electrical stunning on bleeding efficiency, meat quality characteristics, bacterial count, and histology of longissimus thoraces, semitendinosus, biceps femoris, infraspinatus, semimembranosus, and triceps brachii muscles of goats. Forty goats were randomly divided into two groups: electrical stunning and non-electrical stunning with 20 animals each. Low frequency head-only electrical stunning of 1 Amp for 3 s at a frequency of 50 Hz was used. The slaughter was performed by severing the carotid artery, jugular vein, trachea, and oesophagus. Six muscles were kept in a chiller at 3–4 ºC for 24 h before quality measurements. Samples from the infraspinatus, longissimus thoraces, and semitendinosus muscles were preserved to evaluate histological features. Muscle samples from the non-electrical stunning group had substantially higher blood loss and lower bacterial counts after 72 h across the six muscles compared to the electrical stunning group. No significant differences in meat quality parameters were evident between the two groups. The stained sections of the electrically-stunned muscle samples detected alteration phenomena due to the presence of muscle fibres with split myofibres and myofibres with central rather than peripheral nuclei. Electrical stunning prior to slaughter increased bacterial contamination, decreased blood loss, and altered the position of muscle nuclei.","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"20 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"89126410","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 1

Principal Component Analysis of morphometric traits and body indices in South African Kalahari Red goats 南非喀拉哈里红山羊形态计量性状和身体指数的主成分分析

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v53i1.04

Thobela Louis Tyasi, O. Tada

{"title":"Principal Component Analysis of morphometric traits and body indices in South African Kalahari Red goats","authors":"Thobela Louis Tyasi, O. Tada","doi":"10.4314/sajas.v53i1.04","DOIUrl":"https://doi.org/10.4314/sajas.v53i1.04","url":null,"abstract":"Principal component analysis (PCA) is a vital statistical technique for defining the morphological structure of livestock but has not been used in South African Kalahari Red goats. Thirteen morphometric traits and eleven body indices from two hundred and ninety-six (296) South African Kalahari Red goats (269 does and 27 bucks) aged 2–3 years were used to define morphological structure using PCA. The coefficient of determination (R2), root mean square error (RMSE), Akaike’s information criterion (AIC), Mallows' Cp-statistic (Cp), and coefficient of variation (CV) were used to select the best fit model. Body weight was correlated with all morphometric traits in both sexes. The first two principal components explained 87.31% of the variation in measurements from male goats and 62.32% of the trait variation in the females. The inclusion of head length, body length, canon circumference, rump length, rump width, body condition score, wither height, and rump height increased the accuracy to 98% with smaller RMSE (2.42), AIC (55.35), Cp (10.00), and CV (3.98), and the use of PC1 and PC2 included 94% of the variation (RMSE, 3.62; AIC, 72.26; Cp, 3.00; CV, 5.94 in males). In females, the inclusion of all morphometric traits included 87% of the variation (RMSE, 2.93; AIC, 590.63; Cp, 13.00; CV 5.87). The use of PC1 and PC2 included 82% of the variation (RMSE, 3.41; AIC, 663.60; Cp, 3.00; CV, 6.84). PCA can therefore be used in breeding programs to define the morphological structure of South African Kalahari Red goats with a severe reduction in the number of morphometric traits to be recorded.","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"17 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81369336","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of oregano essential oil and capsicum extract supplementation on slaughter characteristics, meat quality, and fatty acid composition of lambs 添加牛至油和辣椒提取物对羔羊屠宰特性、肉品质和脂肪酸组成的影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v52i6.04

H. B. Ünlü, H. İpçak, Ç. Kandemir

{"title":"Effects of oregano essential oil and capsicum extract supplementation on slaughter characteristics, meat quality, and fatty acid composition of lambs","authors":"H. B. Ünlü, H. İpçak, Ç. Kandemir","doi":"10.4314/sajas.v52i6.04","DOIUrl":"https://doi.org/10.4314/sajas.v52i6.04","url":null,"abstract":"The aim of this study was to evaluate the effect of oregano essential oil (OEO) and capsicum oleoresin extract (CAO) supplementation on lamb slaughter characteristics, meat quality, and fatty acid composition. In the study, 18 male and 18 female lambs were divided into three equal groups for a 56- day feeding period. The first group was fed the control diet, while the other groups were fed a control diet containing either 300 mg OEO/kg or 300 mg CAO/kg of diet. Feeding OEO or CAO had no effect on the slaughter and carcass quality of the fattening lambs. However, when compared to the female lambs, the male lambs were found to have higher slaughter weights, hot and cold carcass weights, and dressing percentage, while having lower back fat thickness. In addition, OEO substantially increased the intramuscular fat. Dry matter, protein, pH24, meat colour (L*, a*, and b*), drip loss, and cooking loss were not affected by dietary treatment or sex. The addition of OEO or CAO to the diets did not change the meat lipid oxidation or sensory quality characteristics at different storage times. However, meat from the female lambs was found to have thiobarbituric acid reactive substances (TBARS) values lower than that of the meat from the male lambs after 2 d and 4 d of storage. However, the female lamb meat was more preferred in terms of flavour and general acceptance. The ΣMUFA, ΣPUFA, ΣUFA, Σn-6, Σn-3, and Σn-6/Σn-3 contents of the lamb meat were not affected by the dietary treatment. As a result, the inclusion of 300 mg of oregano essential oil/kg of DM in lamb diets is considered appropriate because of its significant contributions to the fat composition of lamb meat. ","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"153 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78202957","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Influence of a Piriformospora indica plant-specific fungus and clove essence on broiler health and performance parameters during oxidative stress 一种印度梨状孢子虫植物特异性真菌和丁香香精对氧化应激期间肉鸡健康和生产性能参数的影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v52i6.11

Abolfazl Farmani, M. Hedayati, M. Yari, Mehdi Ghabooli

{"title":"Influence of a Piriformospora indica plant-specific fungus and clove essence on broiler health and performance parameters during oxidative stress","authors":"Abolfazl Farmani, M. Hedayati, M. Yari, Mehdi Ghabooli","doi":"10.4314/sajas.v52i6.11","DOIUrl":"https://doi.org/10.4314/sajas.v52i6.11","url":null,"abstract":"The aim of this study was to evaluate the effects of dietary Piriformospora indica (PI) and clove essence (CE) and a combination of them (synbiotic) on performance and biochemical parameters after induction of stress using dexamethasone. The experiment was performed with 320 male, one-day-old chicks (Ross 308) using eight experimental groups and five replications. In each replication, eight chickens were fed a maize–soy-based diet. Experimental groups included group 1 (T1): control diet (based on maize and soybean without any feed additives); group 2 (T2): control diet with 0.2 cc dexamethasone injection; group 3 (T3): control diet with 11.6 cc CE; group 4 (T4): control diet with 10 mg PI; group 5 (T5): control diet with 11.6 cc of CE with 0.2 cc injection of dexamethasone; group 6 (T6): control diet with 10 mg PI and 0.2 cc of dexamethasone; group 7 (T7): control diet with synbiotic containing 10 mg of PI with 11.6 cc of CE; group 8 (T8): control diet with synbiotic containing 10 mg of PI and 11.6 cc of CE with 0.2 mg dexamethasone injection. PI and CE were poured into the drinking water during the rearing period. After 31, 33, 38, and 40 days, 2 mg/kg BW of dexamethasone was injected in the right breast muscle of experimental groups 2, 5, 6, and 8; after 35 and 42 days, samples were taken. The addition of CE, PI, and the synbiotic, caused an increase in body weight gain, feed intake, and reduced FCR compared to the control group in experimental groups 3, 4, and 7. The addition of 11.6 cc CE and 10 mg of PI caused an increase in body weight gain and feed intake and reduced FCR compared to the control group. Dexamethasone (0.2 mg) led to damage of the lymph organs, body weight loss, a reduction in humoral immunity, and side effects on performance parameters. Clove extract and the prebiotic reduced the adverse effects of dexamethasone. ","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"51 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82263620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of production stage and fertility traits on milk production of pasture-grazed Holstein and Jersey cows in a Mediterranean-type climate region 地中海型气候区放牧荷斯坦奶牛和泽西奶牛产奶量的产期和育性性状影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v52i4.15

N. Bangani, C. Muller, K. Dzama, C. Cruywagen, V. Imbayarwo-Chikosi

{"title":"Effects of production stage and fertility traits on milk production of pasture-grazed Holstein and Jersey cows in a Mediterranean-type climate region","authors":"N. Bangani, C. Muller, K. Dzama, C. Cruywagen, V. Imbayarwo-Chikosi","doi":"10.4314/sajas.v52i4.15","DOIUrl":"https://doi.org/10.4314/sajas.v52i4.15","url":null,"abstract":"The aim of this study was to compare the milk production of Holstein and Jersey cows on pasture as affected by parity, lactation stage, calving season, age at first calving, and calving interval. Test-day lactation records of 122 Holstein and 99 Jersey cows, varying from parities 1 to 6, were collected using standard milk recording procedures. Cows were managed and kept as one herd on kikuyu over-sown with ryegrass pasture and received 7 kg of concentrate (as fed) containing 170 g/kg crude protein per day. Across parities, the means for milk yield, milk fat, milk protein, dry matter intake, and body weight were 23.8 ± 6.2 and 17.9 ± 4.4 kg/day; 3.89 ± 0.03 and 4.66 ± 0.03%; 3.17 ± 0.02 and 3.59 ± 0.02%; 17.8 ± 2.6 and 14.4 ± 2.1 kg/day; and 567 ± 3.49 and 411 ± 3.84 kg for Holstein and Jersey cows, respectively. Milk yield increased by 26.5% in Holsteins and 23.7% in Jerseys from first to fourth lactation. Mean lactation number was 2.5 ± 0.15 and 3.0 ± 0.17; test-day milk yield for summer was 21.2 ± 0.28 and 16.5 ± 0.31 kg/day; and winter was 21.3 ± 0.28 and 16.4 ± 0.32 kg/day; age at first calving was 26.4 ± 0.3 and 26.2 ± 0.3; and inter-calving period was 13.9 ± 0.18 and 13.2 ± 0.17 months, for Holstein and Jersey cows, respectively. With inter-calving periods of 13 months, 13.1 to 15.0 and above 15 months, the 305-day Holstein cow milk yield was 7324 ± 181, 7768 ± 193, and 7927 ± 211 kg, whereas that of Jerseys was 5400 ± 135, 5621 ± 244, and 5724 ± 234 kg, respectively. In this study, Jerseys performed better than Holsteins in lactation number and calving interval. Holsteins, however, had a higher increase in milk yield from first to fourth lactation, whereas age at first calving did not differ.","PeriodicalId":21869,"journal":{"name":"South African Journal of Animal Science","volume":"1 1","pages":""},"PeriodicalIF":0.8,"publicationDate":"2023-04-17","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81885704","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Effects of mulberry leaves on growth performance, carcass characteristics, and meat quality of Japanese quail 桑叶对日本鹌鹑生长性能、胴体特性和肉品质的影响

IF 0.8 4区农林科学

South African Journal of Animal Science Pub Date : 2023-04-17 DOI: 10.4314/sajas.v53i1.09

A. Ustundag, M. Ozdogan

引用次数: 0