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1.
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2.
High-quality protein roughage is an important feed for productive ruminants. This study examined the effects of strategic feeding of lactating cows with cassava (Manihot esculenta) top silage (CTS) on rumen fermentation, feed intake, milk yield, and quality. Four early lactating crossbred dairy cows (75% Holstein-Friesian and 25% Thai) with body weight (BW) 410?±?30 kg and milk yield 12?±?2 kg/day were randomly allotted in a 4?×?4 Latin square design to four different supplementation levels of CTS namely, 0, 0.75, 1.50, and 2.25 kg/day of dry matter (DM). Strategic supplementation of CTS significantly affected ruminal fermentation end-products, especially increased propionate production, decreased protozoal population and suppressed methane production (P?<?0.05). Increasing the CTS supplementation level substantially enhanced milk yield and the 3.5% FCM from 12.7 to 14.0 kg/day and from 14.6 to 17.2 kg/day (P?<?0.05) for non-supplemented group and for the 2.25 kg/day supplemented group, respectively. We conclude that high-quality protein roughage significantly enhances rumen fermentation end-products, milk yield, and quality in dairy cows.  相似文献   

3.
Twenty nine Pelibuey × Katahdin hair ewes rearing single lamb were used during 42 days of lactation to evaluate the effect of including the Mucuna pruriens whole pods in the diets of lactating ewes on milk production and offspring performance. Animals were distributed at random into three experimental diets: a control diet without Mucuna (M0), and two more diets with the inclusion of 13 (M13) and 26% (M26), of milled pods of Mucuna pruriens, respectively. Dry matter intake, was not significantly different (P?>?0.05) among diets. Milk yield (P?>?0.05) was 734, 786, and 694 g/day for diets M0, M13, and M26, respectively. Milk fat (P?>?0.05), milk protein (P?>?0.05), and milk lactose (P?>?0.05) did not differ between treatments. Lambs had similar daily weight gain (P?>?0.05) among diets (180, 174, and 171 g/day for diets M0, M13, and M26, respectively). Diets with Mucuna whole pods were 5.6 and 12.9% more profitable (M13 and M26, respectively) than control diet. Under the conditions of this work, Mucuna pruriens whole pods can be included up to 26% in the diets of lactating crossbred hair ewes without negatively affecting their productive performance during the first 6 weeks of lactation.  相似文献   

4.
In the present study, we investigated the effect of grape seed and skin supplement (GSSS), on lactating dairy ewes’ production. Ten dairy pregnant ewes from northern Tunisia were allocated to two groups: control diet (C) and supplemented with 20 % (w/w) GSSS. The experiment lasted for 8 weeks and took place after 2 months of lambing. During the experiment, daily milk yield and milk composition were determined. Supplementation of the diet with GSSS increased milk production (P?<?0.001), calcium (P?<?0.01), free iron (P?<?0.01) and urea content (P?<?0.001) but had no effect on milk fat nor protein. From these data, it is concluded that the inclusion of GSSS in sheep diets increased significantly ewes’ milk yield.  相似文献   

5.
Staphylococcus aureus (S. aureus) is the most prevalent infectious microorganism affecting dairy cattle worldwide, and its pathogenic characteristics facilitate its spread in dairy herds. S. aureus intramammary infections (IMI) are mainly subclinical, and associated losses can exceed average herd losses where the pathogen is not isolated. However, the extent it affects milk composition at udder and quarter levels is still unknown, and cow composite milk losses may be underestimated due to the dilution effect. The aim of this study was to investigate the effects of S. aureus subclinical mastitis on mammary quarter milk yield and composition. In order to determine the effects of the pathogen on milk yield and composition at quarter level, a pairwise comparison of infected and non-infected mammary quarters (n?=?28) from two dairy herds was carried out. Quarters were individually milked, and milk production and composition were assessed. S. aureus has increased somatic cell counts at quarter level; however, no effect of S. aureus IMI on milk lactose, fat, and protein contents was observed. Fat yield from infected quarters decreased, but losses due to the infection caused by S. aureus were not associated with quarter positioning in cows.  相似文献   

6.
Two trials with multiparous dairy cows were conducted. Experiment 1 tested the effects of increasing forage proportion in the diet (500, 600, and 700 g/kg DM) when a mixed sorghum (Sorghum bicolor) and jackbean (Cannavalia ensiformis) silage was used as forage. Experiment 2 studied the substitution of sorghum silage and soybean meal by jackbean silage or fresh cowpea (Vigna unguiculata) forage in the diet. All diets were iso-energetic and iso-proteic. In each experiment, 30 cows were used and separated into three groups. In experiment 1, there were no differences in dry matter intake (DMI), milk yield (MY), or apparent total tract digestibility (aTTd) among the three diets, but milk fat content increased with increasing forage proportion, even though the similar neutral detergent fiber of all diets. Nitrogen use efficiency was highest in the diet containing 600 g forage/kg DM, and some evidence was observed for a better profitability with this forage proportion. In experiment 2, feeding legumes increased DMI despite no effects on aTTd. Milk yield increased in line with DMI, with a larger increase for the fresh cowpea. Nitrogen use efficiency and milk composition were not affected by the diets. The increased MY and lower feed costs increased the economic benefits when feeding legumes, particularly when feeding fresh cowpea. Feeding fresh cowpea or jackbean silage to dairy cows appears to be an alternative to soybean as protein source, ideally at a forage proportions of 600 g/kg DM, without altering milk yield and quality and increasing the farm profitability.  相似文献   

7.
Feeding low-fiber and high-energy diets to dairy cows is one approach to ameliorate heat stress (HS) by reducing heat increment (HI) during digestion. However, rapidly and slowly fermentable cereal grains differ in their HI. The aim of this experiment was to quantify if feeding slowly fermentable grains ameliorated the physiological responses to HS and improved milk production (MP) in dairy cows. Holstein-Friesian lactating dairy cows were housed in shaded pens and were fed either a total mixed ration (TMR) plus wheat (TMRW), a TMR plus wheat treated with 2% of a commercial starch-binding agent (TMRB), or a TMR plus corn (TMRC) (n?=?8 cows per diet) during summer in Queensland, Australia. Respiration rate (RR) and panting score (PS) were measured four times a day; rumen temperature (RuT) was recorded every 20 min, and rectal temperature (RT) and milk samples were obtained every 4 days. Cows fed slowly fermentable grains had higher milk production (MP) than cows fed TMRW, and cows fed TMRC had lower RT than those fed TMRW and TMRB (P?<?0.001). Rumen temperature was positively correlated with temperature-humidity index and negatively correlated with MP (P?<?0.05). In summary, feeding TMRC ameliorated HS as indicated by lower RT and improved MP in dairy cows. Milk production was improved with starch-binding agents; however, this was not associated with efficient thermoregulatory responses. Furthermore, determination of RuT enabled the prediction of changes in physiological variables and productive responses due to HS in lactating dairy cows.  相似文献   

8.
The study investigated the effect of the following maize:legume (70:30) mixed crop silages: maize:cowpea, maize:velvet bean, and maize:lablab on milk production during the 2016 dry season. Using a 5?×?5 double Latin square design, five Holstein-Friesian crossbred cows in early lactation (30?±?15 days) and five Jersey crossbred cows in early lactation (25?±?10 days) were given the supplementary mixed crop silage diets at 0.5 kg/l of milk produced over 105 days. Commercial dairy meal and sole maize silage were used as positive and negative controls, respectively. Milk yield was significantly higher (P?< 0.05) in cows given the dairy meal compared to mixed crop silages; however, milk yield was also significantly higher (P?< 0.05) for cows given the three mixed crop silages compared to cows given sole maize silage. Cows given mixed crop silages produced milk of significantly higher protein content (P?< 0.05) than those given sole maize silage. There was no significant difference (P?> 0.05) in butterfat content of milk across all the dietary treatments. The dietary cost of producing 1 l of milk was highest at 0.31USD/l for cows given commercial dairy meal and lowest for cows given maize:velvet bean and maize:cowpea silage at 0.19USD/kg. The highest dietary gross margins of 68% were observed when cows were given maize:velvet mixed silage compared to commercial dairy meal (47%) and sole maize silage (57%). The 70:30 maize:legume mixed crop silages showed the capability to increase milk quantity and quality at very low production costs in smallholder dairy schemes.  相似文献   

9.
The study assessed the effect of Acacia mearnsii tannin extract supplementation grazing dairy cows on dry matter (DM) intake, enteric methane (CH4) emission, and performance. Twelve Holstein cows were divided into two groups and subjected to two treatments that consisted of millet pasture (Pennisetum glaucum L.) plus supplementation with 6 kg of concentrate (750-g/kg ground corn and 250-g/kg soybean meal) including or excluding 120-g tannin extract. The trial design was a double reversal using three periods of 28 days each, with 21 days for the adaption period, and 7 days for sample collection. Herbage intake was measured using the n-alkane technique, and daily CH4 emission was measured with the sulfur hexafluoride tracer gas technique. Individual total DM intake (mean = 17.1 kg/day), herbage DM intake (mean = 11.8 kg/day), and milk production (mean = 19.2 kg/day) were similar between treatments. CH4 emission significantly decreased (32%, P < 0.05) in the animals supplemented with tannin extract, compared to non-supplemented animals. On the other hand, as proportion of DM intake or milk production, methane emission tended to decrease in tannin-supplemented animals. Supplementing dairy cows grazing a millet pasture with 120-g tannin extract reduced daily CH4 emission without affecting animal performance.  相似文献   

10.
This experiment was conducted to study the effect of reproductive disorders on reproductive efficiency and milk production in relation with pro-inflammatory cytokines in dromedary she-camels. Total of 20 late pregnant Maghrabi she-camels, aging 6–9 years, weighing 420–550 kg, and between the second and third parities were divided into two groups. Animals in the first group (n?=?12) showed normal reproductive status (G1) at parturition, while those in the second one (n?=?8) were suffered from reproductive disorders after parturition (G2). Results showed that during pre-partum, red blood cells (RBCs) count decreased (P?≤?0.05), while white blood cells (WBCs), packed cell volume (PCV) value, and neutrophils percentage increased (P?≤?0.05) in G2 than in G1. Percentages of monocytes, basophils, and eosinophils as well as hemoglobin concentration did not differ significantly (P?≥?0.05) in G1 and G2. During postpartum period, the same results were noticed in addition to increase (P?≤?0.05) in eosinophil and decrease (P?≤?0.05) in basophils percentages. During prepartum period, concentration of total proteins, albumin (AL) and IGF-1decreased (P?≤?0.05), cholesterol concentration, and activity of AST and ALT were higher (P?≤?0.05) in G2 than in G1. Globulin (GL), AL: GL ratio, glucose, urea-N, creatinine, and triglyceride concentrations did not differ significantly in G1 and G2. During postpartum period, the same results were noticed with decrease (P?≤?0.05) in GL and glucose concentrations in G2 as compared to G1. Concentration of all pro-inflammatory cytokines, including IL-6, IL-10, and IFN-γ, was higher (P?≤?0.05) in G2 than in G1 at different peri-parturient times. Milk yield, days in milk, protein and lactose percentages, and IgG concentration were higher (P?≤?0.05) in G1 than in G2. Fat, total solids, solid non-fat, and ash percentages did not show any significant differences between both groups. Reproductive traits, including length of estrous cycle, duration of estrous period, number of services/conception, gestation period, days open, and conception rate, were higher (P?<?0.05) in G1 than in G2. From the present study can be concluded that pro-inflammatory cytokines may be a necessary test for the early diagnosis to prevent related disease in dromedary camels suffering from reproductive disorders. This study indicated strong relationship between hematological parameters and concentration of blood biochemicals and cytokines with reproductive efficiency in camels, which may be helpful in elucidating the adverse effects associated with reproductive disorders.  相似文献   

11.
We studied the feed intake and milk production of Holstein × Zebu crossbred cows fed sorghum silage diets and concentrates, with and without the addition of crambe meal. Using a change-over design for a total of 120 days, eight cows were fed two diets (concentrates + silages with and without crambe meal) in four 30-day periods, with four replications (animals). The crambe meal diet increased (P < 0.05) the dry matter intake (DMI), crude protein intake (CPI), and non-fibrous carbohydrates intake (NFCI) as well as milk production (4.3%). No difference was noted (P > 0.05) for the milk composition between the treatments. Crambe meal as an additive in sorghum silage (100 g/kg in natural matter) showed a great potential for introduction in dairy farming as it substantially increases CP intake, does not reduce food intake, raises animal productivity, and does not affect milk composition.  相似文献   

12.
Inadequate quantity and quality of feed resources are major constraints limiting milk production and reproductive performance of dairy cattle in Ethiopia. The aim of this study was to assess dairy cattle feed resources, feeding practices, the farmers’ perceived ranking of feed resources, causes of feed shortage, and coping strategies to feed scarcity in smallholder dairy system in selected district towns of Jimma Zone, Ethiopia. Data were obtained by interviewing 52 randomly selected smallholder dairy farmers using structured questionnaires and through direct observations. Results showed that 20 main feed types used by dairy farmers were identified and categorized into natural pastures, crop residues, green feeds, hay, agro-industrial by-products, concentrate mix, and non-conventional feeds. Overall, natural pasture (mean rank = 0.453), non-conventional feeds (0.307), cut green feeds (0.086), conserved hay (0.076), crop residues (0.049), and concentrate feeds (0.029) were ranked as the main feed resources in decreasing order of importance. Natural pasture grazing (92.2% of the respondents), hay (35.6%), and green feeds (29.4%) were the most important conventional basal feeds used. Wheat bran (11.7% of the respondents) followed by commercial concentrate mix (9.4%), Noug seedcake (8.3%), grain (7.8%), and molasses (6.1%) were the concentrate supplements used. Overall, bulule-flour mill leftovers (67.2% of the farmers), bean and pea hulls (57.2%) and atella-local brew by-product (37.2%), enset (Ensete ventricosum, 34.4%), and sugarcane top (32.2%) were the non-conventional feeds available and used during feed scarcity. Barley and teff (Eragrostis teff) straws and maize and sorghum stovers were the main crop residues used in the dry seasons. Overall, 73.9, 12.2, 12.2, and 1.7% of the respondents practiced free grazing, zero grazing, semi-zero, and a combination of zero- and free-grazing systems, respectively. Over 84% of the respondents in the dry season and 50% in the wet season reported experiencing a shortage of feeds. Poor feed availability (73.9% of the respondents) was reported as the main causes of feed shortage followed by shortage of pastureland (7.8%). Increased use of bulule (55.6% of the respondents), crop residues (16.1%), non-conventional feed resources (14.4%), conserved hay (11.1%), purchased green feeds and concentrates (1.1%), and reducing herd size (1.1%) were the farmers’ adopted coping strategies to mitigate feed shortage. It is suggested that technical intervention to improve the quality and efficient utilization of the existing feed resources is crucial to enable sustainable feed supply and boost milk production. Technologies that are easy to adopt, feasible, and low cost are also needed to be developed in participatory manner.  相似文献   

13.
The objective of this experiment was to investigate the influence of ground date seed (GDS) on intake, digestibility, and milk yield and milk fatty acid (FA) composition of lactating Holstein cows. The experimental design was a 4?×?4 replicated Latin square with eight lactating dairy cows with an average milk production of 35.5?±?1.5 kg and 75?±?5 days in milk (DIM). Dairy cows were fed one of the four treatments contained 0, 2, 4, and 6% of diet dry matter (DM) GDS in replacement of wheat bran. All diets contained the same amount of forages (alfalfa hay and corn silage). Dietary treatments had no effect on DM intake (DMI), total tract apparent digestibility, milk yield, and milk composition. Increasing GDS linearly decreased concentration of C13:0 and increased cis-9 C14:1 and trans-11 C18:1 (vaccenic acid) (P?<?0.05). A linear tendency for more C16:1 content in milk fat was observed with increasing GDS (P?=?0.06). Feeding GDS resulted in a linear decrease (P?<?0.01) in saturated FA (SFA) but increased milk fat monounsaturated FA (MUFA) and trans FA (TFA) (P?<?0.05). Therefore, low levels of GDS (up to 6%) in the diet of Holstein dairy cows can beneficially modify milk FA composition without any adverse effects on intake, digestibility, and milk yield.  相似文献   

14.
Osteopontin gene is regarded as a plausible candidate in mammary gland differentiation and development, expressed by variety of cells, tissues, and biological fluids including milk. The current study was performed in two phases. In the first phase, Osteopontin gene polymorphisms were identified and associated with milk composition such as ash, milk fat, SNF, lactose, and protein. In the second phase, milk samples from five healthy mastitis-free Nili Ravi buffaloes were analyzed for expression of Osteopontin gene at transition (day 15), mid (day 90), and end (day 250) stage of their second lactation. Briefly, blood samples were collected from Nili Ravi buffalo to isolate the genomic DNA, specific primers were designed for PCR amplification. The amplified PCR products were sequenced bi-directionally. Six polymorphisms were identified in the coding region and four in the intronic region of the gene. The results showed that SNP g.38329758 T > C causing substitution of valine to alanine (V127A) was associated with high milk protein. For mRNA expression analysis, somatic cells were separated from milk samples for RNA isolation. Analysis of differential gene expression data has permitted us to illustrate the expression pattern of osteopontin gene in lactating buffalo. The Osteopontin gene was found to be transcribed among all three lactation stages, but expression was observed with the highest value (fold change) in peak lactation and remained elevated till the end of lactation. Identified gene marker may be helpful for the prediction of superior animal for selection. The presented study also gave an insight into the genetic screening and lactation biology of riverine buffalo, offering direction for future research in lactating buffalo.  相似文献   

15.
We studied influence of distance to urban markets on smallholder dairy farming system development. Farms were chosen from three locations that varied in distance to the urban market of Nakuru Town in the Kenyan highlands: urban location (UL, n?=?10) at less than 15 km distance, mid-rural location (MRL, n?=?11) in between 20 and 50 km west of Nakuru and extreme rural location (ERL, n?=?9) beyond 50 km west and south-west of Nakuru. In-depth interviews with farmers and focus group discussions with eight groups of stakeholders were held to collect narratives and data about market quality, production factors, farm performance and functions of dairy cattle. We applied thematic content analysis to qualitative information by clustering narratives according to predefined themes and used ANOVA to analyse farm data. In UL, markets were functional, with predominantly informal market chains, with a high milk price (US $ 45.1/100 kg). Inputs were available in UL markets, but prices were high for inputs such as concentrates, fodder, replacement stock and hired labour. Moreover, availability of grazing land and the high opportunity costs for family labour were limiting dairy activities. In UL, milk production per cow (6.9 kg/cow/day) and per farm (20.1 kg/farm/day) were relatively low, and we concluded that farm development was constrained by scarcity of inputs and production factors. In rural locations (MRL and ERL), markets were functional with relatively low prices (average US $ 32.8/100 kg) for milk in both formal and informal market chains. Here, concentrates were relatively cheap but also of low quality. Fodder, replacement stock and labour were more available in rural locations than in UL. In rural locations, milk production per cow (average 7.2 kg/cow/day) and per farm (average 18.5 kg/farm/day) were low, and we concluded that farm development was constrained by low quality of concentrates and low price of milk. In all locations, production for subsistence was valued since income generated was used for non-dairy expenses. A tailor-made package of interventions that targets the above constraints is recommended for farm development.  相似文献   

16.
Johne's disease (JD) is caused by infection with the organism Mycobacterium avium spp. paratuberculosis, leading to chronic diarrhoea and ill thrift in adult cattle. JD is considered to adversely affect farm performance and profitability. This retrospective case study was undertaken on a single commercial dairy herd in the south west of Ireland. Animal production records were interrogated to assess the effect of JD on milk yield (total kg per lactation), somatic cell count (the geometric mean over the lactation), reasons for culling, cull price and changes in herd parity structure over time. JD groups were defined using clinical signs and test results. One control animal was matched to each case animal on parity number and year. Specific lactations (clinical, pre-clinical and test-positive only) from 1994 to 2004 were compared between JD case and control cows. A significantly lower milk yield (1259.3 kg/lactation) was noted from cows with clinical JD in comparison to their matched control group. Clinical animals had an average cull price of €516 less than animals culled without signs of clinical disease. In contrast, little effect was noted for sub-clinical infections. These direct effects of JD infections, in combination with increased culling for infertility and increasing replacement rates, had a negative impact on farm production. Results from this study provide preliminary information regarding the effects of JD status on both herd and animal-level performance in Ireland.  相似文献   

17.
Milk yield (MY), composition, and fatty acid profiles of purebred Holstein (HO) cows, Brown Swiss (BS), and their F1 crossbreds (HS) were compared under subtropical climate in Egypt. Pure HO had significantly greater 305-MY, total-MY, and daily-MY (p?<?0.05) than pure BS and crossbred HS. Furthermore, HO and HS had significantly higher peak-MY (44.2 and 43.3 kg, respectively) than BS (36.1 kg). In comparison with HO, BS had significantly higher milk fat, protein, total solids, and solid-not-fat % (p?<?0.05); however, no significant differences were observed between BS and HS for milk fat %. The milk fat of BS had higher concentrations of saturated (C17:0 and C18:0) fatty acids (FA) than that of the HO and HS (p?=?0.001 and 0.008, respectively). Content of C4:0, C6:0, C8:0, C12:0, and C15.0 FA did not differ between genotypes. Milk from HO and BS had significantly higher concentrations of unsaturated (C20:1 and C20:5) FA than that from HS (p?<?0.05). C14:1 (myristoleic), C16:1 (palmitoleic), and C18:2 (linoleic) FA contents were similar for all genotypes. In conclusion, BS surpassed HO for all milk composition traits and some FA components; however, HS had comparable milk fat percentage with BS. There appears to be an opportunity to modify the concentration of certain FA by breeding.  相似文献   

18.
The aim of this work was to evaluate the effect of quebracho tannins extract (QTE) on feed intake, dry matter (DM) digestibility, and methane (CH4) emissions in cattle fed low-quality Pennisetum purpureum grass. Five heifers (Bos taurus × Bos indicus) with an average live weight (LW) of 295 ± 19 kg were allotted to five treatments (0, 1, 2, 3, and 4% QTE/kg DM) in a 5 × 5 Latin square design. Intake, digestibility, and total methane emissions (L/day) were recorded for periods of 23 h when cattle were housed in open-circuit respiration chambers. Dry matter intake (DMI), organic matter intake (OMI), dry matter digestibility (DMD), and organic matter digestibility (OMD) were different between treatments with 0 and 4% of QTE/kg DM (P < 0.05). Total volatile fatty acid and the molar proportion of acetate in the rumen was not affected (P < 0.05); however, the molar proportion of propionate increased linearly (P < 0.01) for treatments with 3 and 4% QTE. Total CH4 production decreased linearly (P < 0.01) as QTE increased in the diet, particularly with 3 and 4% concentration. When expressed as DMI and OMI by CH4, production (L/kg) was different between treatments with 0 vs 3 and 4% QTE (P < 0.05). It is concluded that the addition of QTE at 2 or 3% of dry matter ration can decrease methane production up to 29 and 41%, respectively, without significantly compromising feed intake and nutrients digestibility.  相似文献   

19.
Lippia javanica leaves may have nutraceutical bioactivity and thus could be a viable alternative to antibiotic growth promoters in poultry diets. To test this hypothesis, a feeding trial was carried out to determine the effects of dietary inclusion of Lippia javanica leaf meal (LJ) on growth performance, blood parameters, carcass characteristics and meat quality of indigenous Potchefstroom Koekoek (PK) chickens. The leaf meal was used to dilute a commercial chicken grower diet at a rate of 25 or 50 g/kg diet. Two additional experimental diets, a positive control (commercial chicken grower diet with antibiotics, CON+) and a negative control (commercial chicken grower diet without antibiotics, CON–), were also formulated. Feed intake and growth performance were measured over a period of 13 weeks before slaughtering for carcass and meat quality measurements. Blood was collected in week 11 to determine haematological and serum biochemical parameters. Diet had no effect on overall FCE but significantly (P?<?0.05) affected bilirubin, alanine aminotransferase (ALT), aspartate transaminase (AST), sodium, potassium, cholesterol and magnesium levels in blood. When included at 50 g/kg, LJ increased carcass weight (P?<?0.05). Meat from CON– (6.07) and LJ50 (6.08) chickens had a higher pH than from CON+ (5.9) and LJ25 (5.8) chickens. Breast muscle in CON– chickens had higher (P?<?0.05) lightness (L*) value (53.2) compared to chickens fed on other diets. It was observed that meat from LJ25 chickens had the highest for redness value (2.3). It was concluded that L. javanica leaf meal can be included up to 50 g/kg in Potchefstroom koekoek chicken diets without causing negative effects on the birds’ feed intake, utilisation and weight gain. Diet-induced changes observed in blood parameters and meat quality fell within the expected normal ranges for indigenous chickens.  相似文献   

20.
In vitro activities of 16 antibiotics were tested against 36 Staphylococcus aureus (SA) strains isolated from raw sheep’s milk cheese from six dairies. The minimum inhibitory concentration (MIC) was determined using a broth microdilution method (CLSI). All 36 isolates were analyzed for the presence of the accessory gene regulator gene, agr (I–IV), and genes encoding resistance to methicillin (mecA), erythromycin (ermA), penicillin (blaZ), and vancomycin (vanA-B). The isolates were also analyzed for similarities in pulsed-field gel electrophoresis (PFGE) patterns. SA strains showed resistance to ampicillin (36.1%), penicillin (33.3%), tetracycline (11.1%), and cloxacillin (2.8%) but were susceptible (≥94.4%) to 12 out of 16 tested antimicrobials. The overall susceptibility of the strains to oxacillin, vancomycin, and erythromycin was confirmed by the absence of the mecA, vanA-B, and ermA genes. The PFGE results showed that 32 strains belonged to 10 different clusters (P1–P10) while four strains were untypeable.  相似文献   

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