首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献，搜索用时 62 毫秒
1.
Sixteen bull calves were born in the Spanish Central Pyrenees in spring. They were either early (EW, 90 days of age) or normal weaned (NW, 180 days of age). At day 90, EW calves were placed on an intensive diet while NW calves were turned out with their dams to high mountain pastures. After summer, at day 180, NW calves were weaned and placed with EW calves on a common finishing diet until slaughter at the fixed age of 1 year. From birth to early weaning date, no performance differences appeared. However, EW calves gained faster (1.549 kg/day) than their unweaned counterparts (0.783 kg/day) from early to normal weaning date (P < 0.001). During the finishing period, NW calves showed compensatory growth, with a 44% higher ADG than EW calves (P < 0.001), with a similar feed intake and a better feed conversion ratio. Early weaned calves had a longer fattening phase than NW calves (264 vs. 158 days, respectively; P < 0.001) and thus total feed intake and feed costs were greater. When slaughtered at 1 year of age, EW and NW calves attained similar weight (489 vs. 510 kg, respectively; P > 0.05), but dressing percentage was higher for EW calves (56.9%) than for NW calves (55.2%) (P < 0.01), which led EW calves to have heavier carcasses, without differences in fat score or conformation. The different growth paths, the result of weaning management, did not affect meat tenderness, chemical composition and fatty acid profile, but affected meat lightness, with higher values for compensating calves (NW) than calves in continuous growth (EW). In conclusion, advancing weaning age modified calf performance without affecting substantially carcass characteristics, except for an improvement in dressing percentage, or meat quality.  相似文献   

2.
The impacts of using a modified farrowing pen (MOD) on the performance of sows and their litters and on ambient air quality over a hot and a cool season were evaluated. Primiparous Yorkshire × Landrace sows farrowed either during the months of February and March (thermoneutralily, TN) or June and July (heat-stress, HS). Temperatures within each season were controlled to 21 and 29 °C, respectively, for TN and HS. Animals from each group were assigned to a standard farrowing crate (STD; TN, n = 17; HS, n = 16) or a MOD pen (TN, n = 19; HS, n = 19). The MOD pen consisted of a STD crate with a 1.5 × 1.6-m comfort zone in the back, equipped with rubber floor mats, a feeder and a nipple waterer. Litter size was standardized to 10 or 11. No creep feed was provided and piglets were weighed weekly. Sows were weighed on days 2 and 22. Feed intake of sows was monitored daily, a milk sample was obtained on day 21 for compositional analyses and jugular blood samples were collected on days 2 and 21 to measure prolactin, IGF-I and urea. Sows consumed less feed (3.4 vs. 4.7 ± 0.1 kg/day, P < 0.001) in a hot than in a cool season and, at 29 °C, sows in MOD pens consumed more feed (3.9 vs. 3.0 ± 0.2 kg/day, P < 0.01) than sows in STD pens. Sow lactation weight loss was greater (− 26.4 vs. − 19.1 ± 1.9 kg, P < 0.05) for sows in STD than MOD pens in a hot season. The reduction in prolactin concentrations from days 2 to 22 of lactation tended to be greater (P = 0.08) in a hot season for sows in STD pens. Concentrations of urea and IGF-I increased as lactation advanced (P < 0.01) and IGF-I was lower for HS compared to TN sows on both days (P < 0.01), whereas urea was greater for HS sows on day 2 only (P < 0.01). Milk DM was less in a hot than in a cool season (P < 0.01). Average piglet weight gain was reduced in a hot compared to a cool season during the second week of lactation (P < 0.05) and this reduction was less in MOD than STD pens during the third week of lactation (P < 0.01). During a hot season, even though not significant, average weight gain of piglets from days 2 to 21 of lactation was reduced by 6.0% in MOD pens compared to 9.7% in STD pens.  相似文献   

3.
Aim of the study was to investigate the growth performance of weaned piglets fed either a medicated or not medicated diet supplemented with either a blend of formic and lactic (64/36) acids (FL, 11 kg/ton) or a microencapsulated blend of organic acids and flavors (T) (1 kg/ton, Tetracid®S, EU patent 1391155B1,Vetagro srl, Italy). 480 three-week old SCAAPAG × Goland piglets were fed four diets (4 pens of 30 piglets per diet): FL or T with or without the medication (M) comprising colistin 180 ppm + amoxicillin 600 ppm for the 1st phase and chlortetracycline 1000 ppm + sulphadiazine 1250 ppm + trimetoprim 250 ppm for the 2nd phase. The piglets received a two-phase diet (I:18% CP, 1.3% Lys, 7.5% CF and 2600 kcal/kg NE; II:18% CP, 1.2% Lys, 5.6% CF and 2400 kcal/kg NE). All data were analysed by ANOVA. After 49 days, animals fed the medicated diets had higher feed intake (+ 24.5% for group FL + M vs FL − M and + 22.3% for group T + M vs T − M; P < 0.01) and lower mortality (overall 1.2% for the medicated diets fed animals vs 9.2% for the non-medicated ones). Final weights were: 26.8 ± 1.0 kg, 25.7 ± 0.8 kg for FL + M, T + M, 20.9 ± 0.7 kg, 21.6 ± 0.8 kg for FL − M and T − M, respectively (P < 0.05). The medication resulted in maintaining animals in good health status. The microencapsulation technique allowed to lower the acids dose to be included in the feed by ten fold at least maintaining the same effects that a high dose can give without medication.  相似文献   

4.
A grazing experiment, conducted for 90 days compared the effect of polyethylene glycol (PEG) supplementation on postpartum reproductive traits and productivity of suckling goats grazing Acacia cyanophylla Lindl. A total of 54 native adult goats (34.4 ± 5.49 kg) were randomly allocated, 24 h after kidding, to 2 treatment groups balanced for age and the number of reared kids. Goats in both treatment groups designed C and PEG grazed in acacia for approximately 5 h every day and received each on daily basis 0.3 and 0.4 kg of hay and concentrate respectively. In addition, goats in treatment PEG were initially supplemented with 10 g/day of PEG and this supplement was then increased to 20 g /goat/day over the last 60 days of the trial. Goats receiving PEG tended (P > 0.05) to spend more time browsing acacia than those in treatment C. There were no treatment effects on live weight change of the goats, growth of their kids until 90 days of age or composition of their milk in terms of fat, protein and urea contents. Similar proportions of 74.1 and 77.8% of goats resumed postpartum ovulation with a mean ovulation rate of 1.50 ± 0.61 and 1.67 ± 0.47 (P > 0.05) in respectively the PEG and C treatments. PEG supplementation was associated with an increase (P < 0.05) in ovulation rate at the second postpartum ovulation occurring approximately 27 days after the application of the nutritional treatments (1.76 ± 0.60 versus 1.25 ± 0.45); 9 of the 13 goats ovulating in the PEG treatment were bearing more than one corpus lutuem in comparison to only 3 out of 12 females in the C group (P < 0.05). The likely increased availability of proteins in the PEG receiving goats could explain their higher ovulation rate.  相似文献   

5.
The objective of this study was to compare the effects of ad libitum and restricted computer-controlled milk replacer (MR) feeding strategies on performance of group-reared dairy calves during preweaning (from 0.5 to 2.0 months of age), weaning (2.0 to 2.5) and postweaning (2.5 to 6.0) periods. Two feeding trials comprised a total of 34 Finnish Ayrshire and 6 Holstein–Friesian bull calves. The calves were randomly (balanced for breed) allotted to pens (5 calves/pen) which were thereafter randomly allotted to two experimental treatments: 1) ad libitum MR feeding (F) with ad libitum access to MR and 2) restricted MR feeding (R) where the calves were given 6.0 L of MR daily. All the calves had free access to water, commercial starter and grass silage before weaning. The weaned calves had free access to water and silage and were given 3 kg/day (air-dry basis) of a concentrate mixture. Due to increased metabolizable energy intake (16.4 vs. 12.7 MJ/day; P < 0.05), the daily gain of the F calves was higher (690 vs. 543 g/day; P < 0.05) than that of the R calves during the preweaning period. Due to the more rapid increase in concentrate intake of the R calves during the weaning period the R calves grew better than the F calves (482 vs. 1038 g/day; P < 0.01) and the differences in live weight evened out during the weaning period. During the postweaning period there were no treatment differences in feed intake or gain. The average gain during the whole study was not affected by either of the treatments. Ad libitum feeding increased the variation in the MR intake and gain compared to restricted feeding.  相似文献   

6.
The objective of this study is to characterize the influence of immune stress induced by lipopolysaccharide (LPS) on protein utilization and turnover for early-weaned pigs. A total of 15, crossbred weanling pigs (initial body weight 10.15 ± 0.39 kg) were assigned to one of three treatments. Pigs were injected with LPS and fed ad libitum (LPS-challenge), or injected with endotoxin-free physiological salt solution (PSS) and fed ad libitum (control), or injected with PSS and fed the same amount of feed as LPS-challenged pigs (pair-feed). All pigs received a 4-d nitrogen balance trial. On d 1 and 3 of the trial, LPS-challenged pigs were injected intramuscularly with 200 μg/kg BW of LPS dissolved in 1 ml PSS. Pigs in other treatments were injected with 1 ml PSS. 15N-Glycine (5 mg/kg BW) was gastrically infused after the second injection. Feces and urine were collected daily to determine the N output throughout the duration of the trial. Lymphocyte blastogenesis (LB) and serum immunoglobulins (IgA, IgG, IgM) were also detected to illustrate the LPS-induced immune responses. Results indicated that the injection of LPS significantly (P < 0.01) elevated the LB and resulted in lower average daily gain (ADG), feed intake (ADFI) and efficiency of feed utilization than control pigs. Pair-fed pigs had higher performance than LPS-challenged pig but poorer than control pigs. Injection of LPS also resulted in significantly (P < 0.01) lower nitrogen intake and efficiency of utilization than controls, and more fecal N excretion than Pair-fed pigs (3.19 ± 0.85 vs. 2.19 ± 0.67 g/d, P < 0.05). The whole-body nitrogen flux (4.34 ± 0.19 vs. 11.35 ± 0.12 g N/kg BW0.75/d) and N accretion (5.57 ± 0.59 vs. 10.17 ± 1.12 g Pr/kg BW0.75/d) were acutely (P < 0.01) reduced as the feed intake decreased, but there was no significant difference between LPS-challenged and pair-fed pigs. Injection of LPS markedly (P < 0.05) increased the protein degradation (16.76 ± 1.09 vs. 14.53 ± 1.24 g N/kg BW0.75/d). It is concluded that LPS-induced immune challenge depresses growth performance and feed utilization efficiency by enhancing protein degradation rate and decreasing protein utilization for body protein retention.  相似文献   

7.
In the present study, the effects of natural zeolite clinoptilolite on absorption of immunoglobulins from colostrum and incidence of enteric diseases were evaluated. In a completely randomised design, thirty Holstein calves were fed pooled colostrum and then milk containing zero (control), 0.5 (T1), 1.0 (T2), 1.5 (T3) and 2.0 (T4) g clinoptilolite per kg body weight per day through day 45. Blood was collected after birth and at 24 h of age and plasma IgG and IgM concentrations were determined. Fecal consistency score and severity of diarrhea were recorded for each calf twice daily. Calves receiving T3 and T4 had lower (P < 0.05) plasma IgG concentration than control and other treatments. Calves on T2 had higher (P < 0.05) plasma IgG concentration than T3 and T4, but not T1 and control. Inclusion of clinoptilolite to colostrum did not affect (P > 0.05) IgM absorption from the intestine of newborn calves. Fecal consistency scores were lower (P < 0.05) for calves on T1 and T2 and higher for calves on T3 and T4 than calves on control. Percent calf days with diarrhea followed the same trend. In overall, seven calves died, those being one each on control and T1, two on T3 and three on T4. Based upon these results, addition of 1.0 g clinoptilolite per kg body weight per day to colostrum and milk could reduce diarrhea, but its effect on passive immunity was negligible. Over 1.0 g/kg body weight per day, clinoptilolite had adverse effect on passive immunity and diarrhea.  相似文献   

8.
The low nutrient intake shortly after weaning is a major cause of post-weaning problems. Feed intake after weaning is strongly related to feed intake during lactation. Feed intake during lactation, however, varies considerably between litters. We hypothesised that prenatal and postnatal exposure to certain flavours would increase the intake of feed containing the same flavours pre- and postweaning. Multiparous sows did (n = 17) or did not (n = 14) receive 50 g garlic granulate/powder and 25 g aniseed as daily additive to their diet during the last month of gestation and during lactation. From day 14 of lactation, litters were submitted to intermittent suckling: 12 h separation form the sow each day. During lactation, all litters had 40 g garlic and 20 g aniseed per kg added to their creep feed. After weaning, half of the litters had no additive in their diet. Piglets were weaned at 4 weeks (13 litters) or at 6 weeks (18 litters). At 6 weeks of lactation, litters of which the dam received the flavour in her diet, had a higher feed intake (309 ± 43 vs 233 ± 35 g/p/d) than litters of dams without the flavour, although the difference was not significant. Sow diet had no effect on postweaning feed intake, but postweaning piglet diet did. Late (week 6) weaned litters receiving the flavoured feed had a higher feed intake from 3 to 10 days after weaning (833 ± 38 vs 687 ± 58 g/p/d). Weight gain during the first 10 days after weaning was not affected by sow or pig diets. Feed intake and weight gain shortly after weaning were strongly related to feed intake during lactation (overall R = 0.64, P < 0.05 and R = 0.77, P < 0.05). We conclude that early experience with flavours increases later acceptance and improves adaptation to post weaning conditions.  相似文献   

9.
Fetal protein restriction is potentially associated with organ dysfunctions after birth (e.g. impaired gut growth, glucose tolerance and pancreatic β-cell function). Just after birth, gut growth and maturation is stimulated by enteral food intake, and inhibited by total parenteral nutrition (TPN), in part mediated via differential release of insulino- and intestino-tropic hormones like the Glucagon-Like Peptides 1 and 2 (GLP-1, GLP-2). We hypothesized that short-term co-infusion of GLP-1 and GLP-2 would stimulate pancreatic and intestinal growth in newborn TPN-fed pigs subjected to prenatal protein restriction. Two sows were fed a protein-restricted diet (PR: 8% crude protein during last 50% of gestation) while a third sow was fed a control diet (C: 15% crude protein). PR pigs were killed either at birth (n = 7) or after 3 days TPN with (n = 6) or without (n = 4) intravenous infusion of a mixture of synthetic human GLP-17–37 and GLP-21–33 (each 50 μg/kg/d). At birth, PR piglets did not show reduced body weight, relative to controls (1.45 vs. 1.50 kg), but significantly reduced weight of the small intestine (18.0 ± 0.6 vs. 21.9 ± 0.5 g/kg, P < 0.001) and a marginally reduced pancreas weight (0.85 ± 0.02 vs. 0.93 ± 0.04 g/kg, P = 0.10). Co-infusion GLP-1 and GLP-2 into PR pigs resulted in increased basal glucose levels (5.3 vs. 4.0 mM), and glucose-stimulated insulin release, but did not have any significant effect on body weight, or weight of internal organs (heart, lungs, spleen, kidneys, adrenals, stomach, colon, liver, intestine, pancreas). We conclude that short-term (3 days) infusion of native GLP-1 and GLP-2 does not stimulate gut growth or glucose tolerance in TPN-fed piglets born from protein-restricted mothers. Moderate maternal protein restriction does however cause significant reduction in intestinal growth in newborn piglets which may decrease the neonatal digestive capacity.  相似文献   

10.
Eighteen Iberian barrows of 100 kg initial BW were used in a comparative slaughter experiment to investigate the effects of feeding level (FL; 0.70 and 0.95 × ad libitum) on growth, protein- and fat-deposition rates and body composition. They were fed on a diet supplying the optimum level of digestible ideal protein:ME ratio (4.82 g/MJ) and slaughtered at 150 kg BW. The apparent digestibility of DM, OM, total N and GE, and the ME:GE and ME:DE ratios were not affected by FL. The average daily gain increased with the increase in FL (691 and 918 g/day respectively). Neither the gain:feed (g/g DM) nor the gain:ME intake (g/MJ) ratios were significantly affected however. An energy cost of 59.9 kJ ME/g gain was calculated. The rate of whole-body protein deposition was not significantly altered by FL. On average it reached 80 g/day. The pigs fed at the lowest level exhibited lower fat deposition (P < 0.01) and total energy retention (P < 0.01) than those in the group subjected to only a slight feed restriction. The overall efficiency of utilization of ME for energy gain (ER:ME intake) remained at 0.363 on average, irrespective of the FL imposed. Relative proportions of energy retained as protein and fat were not statistically altered by changes in FL. Mean values for ERP:ER and ERF:ER were 0.100 and 0.903 respectively. No differences between treatments were observed in fat, ash, water or energy content of the whole-body (g/kg) at 150 kg empty BW, the mean values (n = 12) being 512 ± 8.5, 27.6 ± 0.63 and 353 ± 6.7 g/kg for fat, ash and water respectively and 22.90 ± 0.31 MJ/kg for energy. Nevertheless, the proportion of protein tended to decline with the increase in FL (111 vs 104; P = 0.069). At 150 kg the Iberian pigs contained more fat and energy and less ash and water than at 100 kg. Whilst the percentage of lean tissue decreased significantly (P < 0.05) and protein content in the carcass showed a strong tendency to decline in the pigs fed close to ad libitum (104 vs 96; P = 0.056), the proportions of fat, ash, water and energy remained constant at 564 ± 9.0, 22.2 ± 0.91, 312 ± 6.6 g/kg, and 24.82 ± 0.32 MJ/kg, respectively. It was concluded that a degree of feed restriction may result in a discernible improvement in carcass quality.  相似文献   

11.
Effect of floor cooling on performance of lactating sows during summer   总被引：2，自引：0，他引：2  
Forty Landrace × Large White lactating sows were used to evaluate the effects of cooling of the floor when maintained under high temperature conditions during summer on their productive and reproductive performance. The sows were allocated in a completely randomized design with two treatments with 20 replicates according to parity number and body weight, with each animal being considered an experimental unit. The treatments consisted of cooling of the floor under the sow with water circulation at about 17 °C and no cooling. The resulting temperatures of the floor were 27.6 and 35.8 °C for the cooled and the control treatments, respectively. The sows from both treatments were exposed to average maximum and minimum environmental temperatures of 26.9 and 20.8 °C, respectively. Sows maintained on a cooled floor had a higher feed intake (6.47 vs. 5.61 kg/day; P < 0.01). Despite this higher intake, sows maintained on a cooled floor had higher body weight and body protein losses during the lactation period (P < 0.01) in connection with a higher milk yield and subsequent growth of the litter (2280 vs. 1798 g/day; P < 0.01). There was an effect of treatment on rectal temperature, surface temperatures and respiratory rate (P < 0.01) with lower values in sows submitted to floor cooling. It is concluded that floor cooling under the lactating sow improves its productive and reproductive performance, as well as the performance of its litter.  相似文献   

12.
Outdoor reared pigs are reported to be larger at weaning than indoor reared pigs and respond better to the weaning process. This may be due to enhanced gut development associated with increased size. Eighty sows were allocated to either indoor or outdoor farrowing on the basis of size, parity and past performance. Resulting litters were weaned at either 4 or 6 weeks of age. On days 26 and 40 of age, 40 (10/treatment) and 20 piglets (10/treatment still unweaned) were killed to measure intestinal morphology. Data were analysed as a 2 × 2 factorial using the GLM procedures of Minitab 12.2. Pigs reared outdoors were larger than those reared indoors at both weaning ages, pigs weaned at 6 weeks were heavier than those weaned at 4 weeks, 8.4 versus 7.4 kg at 4 weeks and 12.9 versus 10.5 kg at 6 weeks respectively (± 0.25, P ≤ 0.001). There were no differences in small intestine size relative to body weight due to rearing environment and no differences in gut morphology. When corrected for body weight, 6 week pigs had heavier small intestines than 4 week pigs, 0.39 (± 0.010) versus 0.34 (± 0.007) g/cm length, respectively (P ≤ 0.001). Six week unweaned pigs had similar villus heights to 4 week unweaned pigs but wider villi (P < 0.05) and deeper crypts, for example, at the 25% site crypt depths were 236 and 193 μm (± 7.7/5.5) respectively (P < 0.001). Hence increased piglet size due to outdoor rearing did not advance gut maturation whereas increased piglet size due to age did influence maturation of gut structure.  相似文献   

13.
In a 2 × 2 factorial arrangement, 16 groups of 12 pigs (approximately 25 kg) were assigned to either barren or straw housing and to native or pregelatinized potato starch included in the diet (35%) to investigate effects on intestinal weight and gastric lesions. Pigs were fed restrictedly (2.5 × MEm) for 5 weeks. At slaughter, weights of empty small intestine and stomach were determined. Stomachs were inspected for incidence of lesions in the pars oesophagea. No starch type × housing interactions were found. In pigs fed pregelatinized starch, weight of the small intestine (26.8 ± 0.4 g/kg BW) and stomach (7.6 ± 0.1 g/kg BW) were higher than in pigs fed native starch (24.9 ± 0.4; 7.1 ± 0.1 g/kg BW, respectively; P < 0.01). Straw bedding increased empty stomach weight (7.9 ± 0.1 vs. 6.8 ± 0.1 g/kg BW; P < 0.001), but not small intestine weight. Starch type did not affect stomach scores, but straw bedding reduced the incidence of gastric lesions to a very low level (scores 0.5 and 3.0 for straw and barren housing, P < 0.001). In conclusion, straw bedding reduced gastric lesions, reflecting either reduced environmental stress or a positive effect of physical stimulation. Pregelatinization of starch increased the empty weight of the proximal GI tract, possibly reflecting increased nutrient uptake.  相似文献   

14.
The relationship between passage rate of digesta (PRD) and apparent faecal dry matter digestibility (DMD) was investigated in five trials. In trial 1, 2, and 3, 36 weanling (16.9 ± 3.0 kg), 24 growing (51.3 ± 8.8 kg), and 23 finishing (104.8 ± 5.2 kg) barrows were housed in metabolic crates. The beginning and end of 5-day collection periods were marked by the addition of 0.5% indigo carmine to the feed for total faeces collection and PRD determination by observing the time required for the marker to appear. In trial 4 and 5, 21 gestating gilts (215.0 ± 15.0 kg), and 19 lactating sows were individually penned. Addition of 0.5% chromic oxide to the feed enabled indirect determination of DMD and PRD. The PRD, which ranged from 12 to 80 h, was positively correlated with DMD in weanling (R2 = 0.483, P < 0.001), growing (R2 = 0.425, P < 0.01), and finishing (R2 = 0.553, P < 0.001) pigs. Body weight and DMD were not significantly correlated in weanling (R2 = 0.001, P = 0.893), growing (R2 = 0.000, P = 0.995), or finishing (R2 = 0.092, P = 0.156) pigs. A positive correlation between PRD, which ranged from 27 to 102 h, and DMD occurred in gestating gilts (R2 = 0.231, P < 0.05), but not in lactating sows (R2 = 0.014, P = 0.633). The results indicate that longer retention times of digesta improve DMD in swine. Also the results indicate the importance of PRD as a potential independent variable in digestibility assessments.  相似文献   

15.
The objective of this study is to investigate the effect of contrasting spring grazing dates (GD) and stocking rate (SR) on sward characteristics, grass dry matter intake and milk production performance of autumn calving dairy cows during the spring period. Two swards were created by grazing in March (early grazing; E) or by delaying first grazing until mid-April (late grazing; L). Two stocking rates, high (H; 5.5) and medium (M; 4.5) were applied across each sward. Forty eight autumn calving Holstein cows (160 ± 35 days in milk) were assigned to one of four (n = 12) different grazing treatments. The experiment began on April 17th and finished after 2 grazing rotations on June 20th. Later spring grazing significantly increased herbage mass (kg DM/ha) above ground level (+ 933, P < 0.05) and > 50 mm (+ 738, P < 0.05). Compressed sward height (+ 22.1 mm, P < 0.05), extended tiller height (+ 73 mm, P < 0.001) and pseudostem height (+ 35 mm, P < 0.001) were also significantly higher for later grazed swards. In the grazing horizon (> 80 mm— extended tiller height), later grazed swards had significantly lower leaf proportion (− 0.09, P < 0.05) and higher dead material (+ 0.05, P < 0.001). Daily herbage allowance (> 50 mm) was on average 12.7, 15.9, 18.2 and 21.9 kg DM/cow for EH, EM, LH and LM, respectively. Daily leaf allowance (> 80 mm) was 10.1, 12.3, 13.3 and 14.5 kg DM/cow for EH, EM, LH and LM, respectively. The EM (16.2 kg DM/cow), LH (+ 0.1 kg) and LM (0.8 kg) treatments all had similar grass DM intake, however there was evidence of an interaction (P < 0.10) between GD and SR, this was due to the low grass DM intake of the EH (13.9 kg DM/cow) treatment. When expressed as UFL (Fill unit) intake the EM treatment recorded the highest value. There was a significant interaction between GD and SR (P < 0.01) for milk, protein yield, 4% fat corrected milk yield (P < 0.05) and protein concentration (P < 0.001). Cows grazing the EM treatment produced 23.9 kg of milk, 876 and 685 g of fat and protein yield. The difference in milk production (cow/day) between EM and EH treatments was + 3.6 kg milk, + 98 g fat and + 107 g protein. The production yield difference between LM and LH treatments was + 1.1 kg milk, + 27 g fat and + 29 g protein in favour of the LM treatment (23.9 kg of milk, 877 and 687 g fat and protein yield). Herbage quality and morphological characteristics are clearly improved with early spring grazing as herbage mass is reduced on subsequent rotations. Swards grazed in early spring allow higher grass utilisation and high milk production performance when grazed at a medium stocking rate. Improved milk production from herbage can be achieved provided herbage mass and allowance are maintained at levels where herbage quality decreases are minimised.  相似文献   

16.
A 2 × 2 factorial experiment was used to investigate the interaction between dietary crude protein (CP) concentration (200 vs 140 g/kg) and inulin supplementation (0 vs 12.5 g/kg) on nitrogen (N) excretion and intestinal microflora from 16 boars (n = 4, 74.0 kg live weight). The diets were formulated to contain similar concentrations of digestible energy and lysine. Pigs offered the high CP diets had a higher excretion of urinary N (P < 0.01), faecal N (P < 0.01) and total N (P < 0.001) than the pigs offered the low CP diets. Inulin supplementation increased faecal N excretion (P < 0.05) and decreased urine: faeces N ratio (P < 0.05) compared to the inulin free diets. There was no significant effect (P > 0.05) of dietary treatment on N retention. There was an interaction (P < 0.05) between dietary CP concentration and inulin supplementation on caecal E.coli. Pigs offered the diet containing 200 g/kg CP plus inulin decreased the population of E.coli compared to the inulin supplemented 140 g/kg protein diet. However, CP concentration had no significant effect on the population of E.coli in the unsupplemented diets. Inulin supplementation increased caecal bifidobacteria (P < 0.01) compared to the inulin free diets. In conclusion, inulin supplementation favourably altered N excretion and lowered the population of E.coli at high CP concentrations.  相似文献   

17.
The experiment studied the effects of long-term cold climatic housing conditions at a latitude of 62°N on pregnant Hereford cows and their progeny. Thirty-five cows in their third parity were overwintered in outdoor facilities with either a rain-shelter or a three-wall shelter, or in an uninsulated barn. Whole-crop barley silage was offered to the cows either ad libitum or restricted supplemented with oats. The dry matter intake on the restricted diet was 75% of that on the ad libitum diet. The cow live weight (LW) averaged 670 kg at the onset of the experiment. During winter the cows outdoors on the restricted diet maintained their LW while those on the ad libitum diet gained LW (P < 0.05, − 3 vs. 41 kg). On pasture, the LW gain (LWG) was 61 and 32 kg (P < 0.05) for the cows overwintered outdoors on the restricted and on the ad libitum diets, respectively. The initial body condition score (BCS, Scale: 0–5) of the cows averaged 2.90. During winter the cows outdoors on the restricted diet decreased and those on the ad libitum diet increased the BCS (P < 0.01, − 0.14 vs. 0.21). On pasture, the cows overwintered outdoors on the restricted diet increased the BCS more than those overwintered on the ad libitum diet (P < 0.05, 0.31 vs. 0.08). No signs of extraordinary stress, massive consumption of energy stores, frequent muscle injuries or severe inflammations occurred in any of the groups according to blood analyses of cows, e.g. cortisol, long-chain fatty acids, aspartate aminotransferase, creatine kinase and white blood cell count. The calving period was from 11 March to 21 April. Only one indoor calving was classified as difficult due to faulty disposition leading to the loss of the calf. All outdoor calvings were easy. The LWG of the indoor calves of cows on the ad libitum diet was poorer (P < 0.05) pre the grazing period than that of the outdoor calves of cows on the ad libitum diet. On pasture and during the entire experiment the LWG was similar for all calves, averaging 1335 and 1251 g/d, respectively. The breeding season was 82 days. Thirty cows out of 33 were observed to be pregnant after the mating period. All the facilities offered adequate shelter for the mature, pregnant suckler cows. The restricted offering of whole-crop barley silage provided, on average, 101 MJ metabolizable energy/d and gave enough energy for the cows.  相似文献   

18.
Two experiments were undertaken to examine the direct and residual responses of late lactation (mean of 232 days calved) autumn calving dairy cows (Experiment 1), and late lactation (mean of 240 days calved) spring calving dairy cows (Experiment 2), to once-daily milking. Experiments 1 and 2 involved 50 and 44 Holstein–Friesian dairy cows respectively. In each of the two experiments, cows were milked either once daily (ODM) or twice daily (TDM), during the late lactation period (mean of 79 and 66 days in Experiments 1 and 2 respectively). Cows in Experiment 1 were managed within a grazing system, and were offered 3.0 kg of concentrate/day, while cows in Experiment 2 were housed, and offered grass silage supplemented with 6.0 kg concentrate/day. Forty-one cows from Experiment 1, and 32 cows from Experiment 2, completed the first eight weeks of the subsequent lactation on a twice-daily milking regime. Food intakes were not measured in Experiment 1, while treatment had no significant effect on dry matter intake in Experiment 2 (P > 0.05). In each of Experiments 1 and 2, total milk output was increased with twice-daily milking (P ≤ 0.05), while milk fat (P ≤ 0.01) and protein (P < 0.001) concentrations increased with once-daily milking. Somatic cell counts were higher with animals milked once daily in Experiment 1 (P < 0.001), while not being significantly affected by milking frequency in Experiment 2 (P > 0.05). Milking frequency had no significant effect on cow live weight or on cow condition score at the point of drying off in either Experiment (P > 0.05). Milking time per cow during morning milking was unaffected by treatment in either experiment, while total daily milking time per cow (morning and evening combined) was significantly longer with the TDM treatment (P < 0.001). In Experiment 1, milk flow rates during the morning milking were higher with animals on the ODM treatment, compared to those on TDM treatment (P < 0.001), while being unaffected by treatment in Experiment 2 (P > 0.05). Neither daily milk yield, milk fat content, milk protein content, or somatic cell count during the subsequent lactation, were affected by previous lactation milking frequency in either of Experiments 1 or 2 (P > 0.05).  相似文献   

19.
Belgian Blue (BB) beef cattle is particularly prone to selenium (Se) deficiency due to the poor Se content of soil and roughages on rearing farms and the higher requirements of this hypermuscled breed. The goal of this trial was to compare the effects of different forms and concentrations of Se supplementation on Se status, health and performance in 60 pregnant Se-deficient BB cows. Cows were allocated to 3 experimental groups receiving selenized-yeast at 0.5 ppm Se on total ration (Y–Se 0.5), Na–selenite at 0.5 ppm Se on total ration (Na–Se 0.5) and Na–selenite at 0.1 ppm Se on total ration (Na–Se 0.1), respectively. Cows were supplemented from 2 months before calving until 2 months after calving. Data on performance, health and Se status of the dams and their calves were analyzed using a linear model, least squares means and logistic regression. At the end of the study, plasmatic Se (pSe) was significantly higher (P < 0.01) in cows receiving Y–Se than in cows from other groups. Glutathion-peroxidase in erythrocytes (GSH-pxe) was higher in Y–Se and Na–Se 0.5 than Na–Se 0.1 group (P < 0.01). Se content in colostrum and milk was significantly higher (P < 0.01) in Y–Se than other groups. At birth, Se status of calves from group Y–Se was significantly higher than those of other groups (P < 0.01). Plasmatic Se in calves remained higher for 75 days after birth in Y–Se compared to other groups (P < 0.01). Diarrhoea was the most commonly observed disease in the calves and, during the first 15 days of life, diarrhoea occurred in 6%, 21% and 35% of calves from groups Y–Se, Na–Se 0.5 and Na–Se 0.1, respectively. Over the whole 75 days trial period, incidence of diarrhoea was 19, 29 and 65%, respectively. Average daily gain (ADG) in calves born from Y–Se group of cows tended to be higher than in Na–Se 0.5 (P = 0.06) and Na–Se 0.1 (P < 0.05) but there was no difference between Na–Se 0.5 and Na–Se 0.1 (P > 0.1). At the same dosage, Y–Se conferred better Se status in both dams and their calves than did Na–Se. Requirement of 0.1 ppm Se seems to be insufficient in BB to optimise health and performance. Regarding health status and ADG in calves, Y–Se seems also to result in better performance.  相似文献   

20.
Forty multiparous cows (599 kg ± 18 kg BW) were fed with a basal diet (19.6% CP, 35% RUP, and 1.7 Mcal kg− 1 NEl) with alfalfa, corn silage and concentrate (49% forage: 52% concentrate). After calving, cows were randomly assigned to the treatments, which consisted in four levels of ruminally protected methionine (RPM): 0, 8, 16 and 24 g d− 1 of Mepron®M85 (Degussa Co.). Experiment was conducted for 120 days with measurements of milk production, composition, body weight, body condition score and DM intake every 15 days (3 consecutive days) starting on day 5 postpartum. Data were analyzed with the repeated measures model (four treatments in 8 periods through lactation). No treatment effects were detected on DM intake (20.38 ± 2.51 kg d− 1), body weight (599.78 ± 19.78 kg), body condition score (2.51 ± 0.19 units) and milk fat. However, milk production and protein yield were increased with addition of RPM (P < 0.01). Milk production responded quadratically to methionine level. Holstein cows with a mean production of 35 kg d− 1 milk require addition of ruminally protected methionine (16 g d−1) to improve milk production.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号