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1.
To determine how nutrient restriction and melatonin supplementation influence ewe and foetal hepatic and small intestinal energy use, 32 primiparous ewes on d 50 of gestation were fed 60% (RES) or 100% (ADQ) of NRC recommendations with 0 (CON) or 5 mg/d (MEL) of dietary melatonin. On d 130 of gestation, small intestine and liver were weighed and collected. Data were analysed as a completely randomized design with a 2 × 2 factorial arrangement of treatments. Liver weight (g/kg EBW) decreased (p = 0.02) in RES ewes. Jejunum weight (g/kg BW) increased (interaction p = 0.04) in ADQ‐MEL ewes compared with all other treatments. Total in vitro O2 consumption (mol/min/tissue) and total citrate synthase activity (mol/min/tissue and mol/min/kg EBW) in liver decreased (p ≤ 0.03) in RES ewes. Oxygen consumption (mol/min/kg EBW) increased (interaction p = 0.02) in jejunum of ADQ‐CON versus RES‐MEL and ADQ‐CON. Citrate synthase activity (mol/min/kg of EBW) increased (interaction p = 0.03) in jejunum of ADQ‐MEL compared with RES‐MEL and ADQ‐CON. Foetal liver weight (g/kg BW) decreased (p = 0.02) in RES versus ADQ. Foetal small intestine weight (g/kg BW) decreased (interaction p = 0.05) in RES‐MEL versus ADQ‐MEL. Total O2 consumption (mol/min/tissue) and total citrate synthase activity (mol/min/kg of BW) in foetal liver decreased (p ≤ 0.05) in RES versus ADQ. Foetal small intestinal O2 consumption (mol/min/kg of BW) was greater (interaction p = 0.03) in RES‐CON and ADQ‐MEL than RES‐MEL and ADQ‐CON. Maternal nutrient restriction had a greater effect than melatonin supplementation on liver and jejunum mass and energy utilization in dams and foetuses. Because intestinal mass and energy utilization were more responsive to melatonin supplementation in ewes fed adequate nutrition compared with restricted ewes, melatonin may have limited use as a therapeutic supplement to help overcome potential negative effects of nutrient restriction.  相似文献   

2.
This study's objective was to determine if nutrient restriction during late gestation affected beef heifer feed intake, body weight (BW) gain and endocrine regulation during a 10‐week feeding trial. During the last 100 days of gestation, control (CON) dams were fed to increase body condition score (BCS). Whereas, nutrient‐restricted dams (NR) and NR dams protein supplemented 3 days/week (NRS) were fed to decrease BCS by 1.2. After parturition, all cow‐calf pairs were moved to a common pasture and fed in excess of requirements until weaning. At 15 months of age, heifers were randomly sorted into two pens and adjusted to a commercial total mixed ration over a 2‐week period. Blood samples and BW were taken at the initiation of feeding and on a biweekly basis for the duration of the feeding trial. Feed intake was monitored for 10 weeks using a GrowSafe System. After 10 weeks, an intravenous glucose tolerance test (IVGTT) was performed on 21 randomly subsampled heifers. During the feeding trial, NR heifers consumed more feed than CON and NRS heifers. Heifers from NR dams tended to increase BW compared to NRS and CON heifers when adjusted for initial BW. Heifers from NR and NRS dams had a greater increase in BCS compared to heifers from CON dams. Plasma glucose and insulin concentrations during the feeding trial increased in NR heifers compared to the other groups beginning at 2 and 4 weeks respectively. Plasma leptin concentrations were increased in the NR and NRS heifers compared to the CON heifers beginning at week 4 of feeding. During the IVGTT at the conclusion of the feeding challenge, plasma glucose and insulin were increased in NR heifers compared to other treatment groups. These results show that nutrient restriction during late gestation alters appetite and endocrine regulation in heifer offspring.  相似文献   

3.
The objective of this study was to determine the effects of different forage sources on the growth performance, nutrient digestibility and blood metabolites of dairy calves. Individually housed calves (n = 40; body weight = 41.2 ± 3.5 kg) were randomly allocated (n = 10 calves per treatment: five males and five females) to one of the following four treatments: (i) starter without forage provision (CON), (ii) starter plus chopped alfalfa hay (AH), (iii) starter plus chopped wheat straw (WS) and 4) starter plus dried sugar beet pulp (BP) flakes. Calves fed AH diets had lowest (p < 0.05) starter intake than those fed other diets, and WS promoted a significant increase (p < 0.01) in starter intake during 43–80 days. Forage intake was greatest (p < 0.01) for calves fed AH than those fed WS and BP. Calves in the AH treatment consumed less (p < 0.01) total dry matter intake than those offered other forage treatments. Final body weight was greatest (p < 0.05), and age of weaning was lowest for calves fed BP than other treatments. Calves in the BP treatment had greater (p < 0.05) average daily gain (ADG) than CON and WS treatments, but similar to AH calves. Digestibility of NDF and ADF was greater (p < 0.05) in BP treatment than other treatments. Calves fed BP had greater (p < 0.05) digestibility of DM and OM than those fed CON diets and similar to those fed AH and WS diets. Calves in the AH treatment had greater (p < 0.05) CP digestibility than CON, but similar to WS and BP calves. Blood beta‐hydroxybutyrate concentration was lower in forage‐offered calves than CON one. Body measurements (with the exception of body barrel) did not differ across treatments. It was concluded that BP improves final body weight, ADG and nutrient digestibility of calves than starter without forage provision during weaning transition.  相似文献   

4.
The potential effect of dietary forage supplementation on the performance and rumen development in dairy calves is well established. However, limited research has been directed to the comparative effects of forage offering methods on calf performance. The objective of the present study was to determine the effects of forage provision methods (total mixed ration or free choice) on the performance, nutrient digestibility, rumen fermentation and nutritional behaviour in newborn calves. Forty‐five Holstein dairy calves (3 days of age and 41 ± 2 kg of body weight) were assigned to the following three groups (n = 15): (i) starter without forage provision (CON), (ii) starter supplemented with 10% alfalfa hay (AH) as a total mixed ration (AH‐TMR) and (iii) starter and AH as a free‐choice provision (AH‐FC) for a period of 70 days. All the calves were offered 5 l of milk/day from day 3 to 50, and 2.5 l/day from day 50 until weaning on day 56. Dry matter intake (DMI) was greater (p < 0.01) in the AH‐TMR and AH‐FC treatments than in the CON during the pre‐ and post‐weaning periods. Calves fed the AH‐FC diet showed the highest post‐weaning DMI among the treatments. The calves receiving ad libitum forage tended (p = 0.08) to increase crude protein digestibility and overall volatile fatty acids (VFA) concentrations in the rumen. No differences were observed among the treatments at the time spent on standing, lying, eating and performing non‐nutritive oral behaviours. Compared to CON calves, animals in the AH‐TMR treatment spent more time (p < 0.05) ruminating. In conclusion, our data suggest that forage supplementation in both forage offering methods increased total DMI, ruminal pH and ruminating time in dairy calves. Hence, there is no benefit in the free‐choice provision of AH in dairy calves.  相似文献   

5.
The effects on cow and calf performance of replacing grass silage with brewers grains in diets based on barley straw and fed to pregnant beef cows are reported. Using a 2 × 2 factorial arrangement of breed and diet, cows pregnant by artificial insemination (n = 34) of two breeds (cross‐bred Limousin, n = 19 and pure‐bred Luing, n = 15) were fed diets ad libitum which consisted of either (g/kg dry matter) barley straw (664) and grass silage (325; GS) or barley straw (783) and brewers grains (206, BG) and offered as total mixed rations. From gestation day (GD) 168 until 266, individual daily feed intakes were recorded and cow body weight (BW) and body condition score (BCS) measured weekly. Calving date, calf sex, birth and weaning BW, and calf age at weaning were also recorded. Between GD 168 and 266, cross‐bred Limousin cows gained more weight than Luing cows (p < 0.05) and cows offered BG gained more weight than cows offered GS (p < 0.001). Luing cows lost more BCS than cross‐bred Limousin cows (p < 0.05), but diet did not affect BCS. There were no differences in dry matter intake as a result of breed or diet. Calf birth BW, however, was greater for cows fed BG than GS (44 vs. 38 kg, SEM 1.0, p < 0.001) with no difference between breeds. At weaning, calves born to BG‐fed cows were heavier than those born to GS‐fed cows (330 vs. 286 kg, SEM 9.3, p < 0.01). In conclusion, replacement of grass silage with brewers grains improved the performance of beef cows and increased calf birth and weaning BW. Further analysis indicated that the superior performance of cows offered the BG diet was most likely due to increases in protein supply which may have improved both energy and protein supply to the foetus.  相似文献   

6.
Study 1, pregnant crossbred, first-calf heifers (n = 149; BW 493.8 ± 6.3) received gestation diets: control (CON), or added safflower seeds (SAFF), raw soybeans (SOY), or sunflower seeds (SUN). Diets were formulated isocaloric-isonitrogenous, contained 2.4, 4.7, 3.8, or 5.1% fat, and were fed for the last 65.3 ± 4.6 d precalving. Supplemental fat feeding was terminated at calving. Diet effects on dam BW or condition scores and calf birth BW, calving difficulty, and dam estrous cyclicity were generally nonsignificant (P>0.10). Fat-supplemented dams had greater pregnancy rates (P<0.05) and fall calf BW (P=0.08): CON, 79%, 182.4 kg; SAFF 94%, 194.9 kg; SOY, 90%, 197.7 kg; SUN, 91%, 196.8 kg. Study 2, pregnant crossbred, first-calf heifers (n = 83; BW 439.8 ± 7.3) received gestation diets: control (CON2) or added sunflower seeds (SUN2). Diets were formulated isocaloric-isonitrogenous, contained 2.2 and 6.5% fat, and were fed for the last 68.2 ± 5.5 d before calving. Supplemental fat feeding was terminated at calving. Blood samples were collected during the feeding period. Diet effects on dam BW, condition scores, estrous cyclicity, and pregnancy percentage were nonsignificant. Calf birth BW from SUN2 dams tended (P=0.06) to be greater. Diet effects on blood components were nonsignificant except for NEFA concentrations tending to be lower in SUN2 dams at the initial (P=0.08) and mid-gestation feeding (P=0.06) sampling. Major differences were found in forage availability between Studies 1 and 2. We conclude that dietary fat or fatty acids may be an important “reproductive fuel,” and effects of supplemental gestation fat may be masked when adequate nutrients are available in forages consumed postpartum.  相似文献   

7.
The effects of dietary β‐hydroxy‐β‐methylbutyrate (HMB) supplementation during gestation on reproductive performance of sows and the mRNA expression of myogenic markers in skeletal muscle of neonatal pigs were determined. At day 35 of gestation, a total of 20 sows (Landrace × Yorkshire, at third parity) were randomly assigned to two groups, with each group receiving either a basal diet or the same diet supplemented with 4 g/day β‐hydroxy‐β‐methylbutyrate calcium (HMB‐Ca) until parturition. At parturition, the total and live litter size were not markedly different between treatments, however, the sows fed HMB diet had a decreased rate of stillborn piglets compared with the sows fed the control (CON) diets (p < 0.05). In addition, piglets from the sows fed HMB diet tended to have an increased birth weight (p = 0.08), and a reduced rate of low birth weight piglets (p = 0.05) compared with piglets from the CON sows. Nevertheless, lower feed intake during lactation was observed in the sows fed the HMB diet compared with those on the CON diet (p < 0.01). The relative weights of the longissimus dorsi (LD) and semitendinosus (ST) muscle were higher (p < 0.05) in neonatal pigs from the HMB than the CON sows. Furthermore, maternal HMB treatment increased the mRNA levels of the myogenic genes, including muscle regulatory factor‐4 (MRF4, p < 0.05), myogenic differentiation factor (MyoD) and insulin‐like growth factor‐1 (IGF‐1, p < 0.01). In conclusion, dietary HMB supplementation to sows at 4 g/day from day 35 of gestation to term significantly improves pregnancy outcomes and increases the expression of myogenic genes in skeletal muscle of neonatal piglets, but reduces feed intake of sows during lactation.  相似文献   

8.
The objective of this study was to evaluate the effects of increasing garlic powder and monensin supplementation on feed intake, nutrient digestibility, growth performance and blood metabolites of growing calves. Forty Holstein calves (BW = 100 ± 11 kg) were randomly assigned to four dietary treatments (n = 10) in a complete randomized design. Experimental treatments consisted of the following: (i) basal diet (control), (ii) basal diet supplemented with 0.0003% of dietary dry matter (DM) sodium monensin, (iii) low level of garlic powder (Low‐GAR; 0.5% of dietary DM) and (iv) high level of garlic powder (High‐GAR; 1% of dietary DM). DM intake (DMI) and DM digestibility were (p < 0.05) decreased by High‐GAR. However, calves supplemented with Low‐GAR had a similar DMI to the control calves and similar DM digestibility to the control and monensin groups. The digestibility of other nutrients were not affected by the treatments. Although supplementing monensin relative to Low‐GAR increased the DMI (p < 0.05), average daily gain was similar between Low‐GAR and monensin supplemented calves, which were higher than the control and High‐GAR groups (p < 0.05). As a result, feed conversion ratio was improved in the Low‐GAR group versus other treatment groups (p < 0.05). Administrating garlic powder decreased the blood low‐density lipoprotein (LDL) and non‐esterified fatty acids (p < 0.05) without affecting the blood triglyceride, high‐density lipoprotein and beta‐hydroxybutyric acid concentrations. In conclusion, the calves fed the Low‐GAR showed an improved FCR and blood metabolites without changing the DMI and nutrient digestibility. It suggests that garlic powder could be used as an alternative to monensin for growing calves under the current feeding conditions.  相似文献   

9.
The objective of this experiment was to investigate the effects on performance, weaning age and rumen fermentation characteristics in Holstein calves when fennel powder was added to their starter diets. Thirty Holstein calves with a mean birth weight 40 kg (SD = 0.5) were allocated randomly to one of the following experimental diets: (i) control (starter diet without fennel powder), (ii) starter diet containing 0.4% of fennel powder and (iii) starter diet containing 0.8% of fennel powder (DM basis). The effect of treatments on mean dry matter intake was significant (p < 0.05) in the post‐weaning and total experimental periods. Average daily weight gain before (0.38, 0.49 and 0.47 kg/day) and after (0.6, 1.01 and 0.83 kg/day) weaning and during the entire study (0.45, 0.7 and 0.58 kg/day) was influenced by diets of 1, 2 and 3, respectively (p < 0.05). Maximum daily weight gain and the best feed conversion ratio were achieved with 0.4% fennel powder. Mean weaning age of the calves supplemented with fennel powder was lower (p < 0.05) than that of the control group. Ruminal fluid pH in calves offered starter containing 0.8% fennel powder was lower (p < 0.05) compared to calves fed the other diets. Ammonia nitrogen content increased (p < 0.05) in the third week of feeding fennel powder. The mean concentration of total short‐chain fatty acids (SCFA) and propionate molar percentage in the ruminal fluid of the calves fed with the fennel powder were higher (p < 0.05) at 6 weeks and 2 weeks after weaning than control group; however, acetate‐to‐propionate molar ratio was lower (p < 0.05). The results showed that adding 0.4% fennel powder to the starter increased the propionate molar percentage in the rumen and improved the calf performance, allowing the calves to be weaned at an earlier age.  相似文献   

10.
Our objectives were to examine the effects of added fat in late-gestation cow diets on neonatal response to cold. In Exp. 1, pregnant fall-calving heifers received control (n = 5), safflower seed (n = 5), or whole cottonseed (n = 5) diets. The hay-based, isonitrogenous, and isocaloric diets, fed for 47 d prepartum, contained 1.5, 4.0, and 5.0% fat for control, safflower, and whole cottonseed diets, respectively. At calving, calf BW and vigor score, as well as fat, lactose, and IgG in colostrum were not affected (P > 0.30) by diet. Heifers fed the safflower diet tended to have greater colostral solids (P < 0.10) than heifers fed the control or whole cottonseed diets. At 6.5 h of age, calves were placed in a 5 degrees C cold room for 90 min. Calf vigor, shivering, body temperature, and blood samples were taken every 15 min. During cold stress, calf body temperature decreased 0.7 degrees C (P < 0.03). Across all diets, shivering and serum glucose concentrations increased (P < 0.05), whereas calf vigor and cortisol concentrations decreased (P < 0.02) during cold exposure. In Exp. 2, pregnant spring-calving cows (n = 98) received a control (n = 47) or whole cottonseed (n = 51) supplement. Hay-based diets fed for 68 d prepartum contained 2.0 and 5.0% fat for control and whole cottonseed diets, respectively. Calf BW, vigor, shivering, dystocia score, time to stand, time to nurse, serum glucose concentrations, and serum IgG were not affected (P > 0.50) by diet. Between 30 and 180 min, body temperature of calves from dams fed the whole cottonseed supplement decreased (P < 0.05) more than calves from dams fed the control supplement. Serum glucose concentrations in calves were not affected by diet (P > 0.30). Serum cortisol concentrations tended (P < 0.09) to be greater for calves from dams fed whole cottonseed than control calves. When ambient temperature was < 6 degrees C, calves born to dams fed whole cottonseed had greater (P < 0.05) BW, tended (P < 0.1) to stand earlier, and had greater serum IgG concentrations. We conclude that calves from dams fed high-fat diets containing safflower or whole cottonseed respond similarly to cold stress, but these responses may not be consistent with greater cold resistance. In addition, high-fat dietary supplementation of late-gestation cows may only be beneficial during calving seasons with prolonged cold weather.  相似文献   

11.
Altering the composition of the bovine vaginal microbiota has proved challenging, with recent studies deeming the microbiota dynamic due to few overall changes being found. Therefore, the objectives of this study were to determine whether gestational age, endogenous progesterone, maternal nutrient restriction, or dietary melatonin altered the composition of the bovine vaginal microbiota. Brangus heifers (n = 29) from timed artificial insemination to day 240 of gestation were used; at day 160 of gestation, heifers were assigned to either an adequate (ADQ; n = 14; 100% NRC requirements) or restricted (RES; n = 15; 60% NRC requirements) nutritional plane and were either supplemented with dietary melatonin (MEL; n = 15) or not supplemented (CON; n = 14). Samples for vaginal microbiota analysis were taken on day 0 (prior to artificial insemination), day 150 (prior to dietary treatments), and day 220 of gestation (60 d post-treatment initiation) using a double guarded culture swab. The vaginal bacterial overall community structure was determined through sequencing the V4 region of the 16S rRNA gene using the Illumina Miseq platform. Alpha diversity was compared via 2-way ANOVA; β diversity was compared via PERMANOVA. The linear discriminant analysis for effect size (LEfSe) pipeline was utilized for analysis of taxonomic rank differences between bacterial communities. Gestational age, progesterone concentration, and maternal nutritional plane did not alter α or β diversity of the vaginal microbiota. However, gestational age resulted in compositional changes at the order, family, and genus level. Moreover, dietary melatonin supplementation did not alter α diversity of the vaginal microbiota but did alter β diversity (P = 0.02). Specifically, melatonin altered the composition at the genus level and increased the prevalence of aerobic bacteria in the vaginal tract. To date, melatonin is the first hormone associated with altering the composition of the bovine vaginal microbiota.  相似文献   

12.
Hy‐Line Gray commercial pullets were maintained under 8‐h photoperiods, 16‐h photoperiods and 16‐h photoperiods supplemented with a diet containing 20 or 200 mg/kg melatonin (MEL) to investigate the role of MEL in sexual development. A total of 256 Hy‐Line Gray commercial pullets were placed, four birds to a cage, in four similar light‐proof rooms (8‐h photoperiod) at 6 weeks of age. At 70 day, three rooms containing a total of 192 birds were transferred to a 16‐h photoperiod, whereas 64 birds were maintained under the 8‐h photoperiod. Diets containing MEL at 20 and 200 mg/kg were fed to birds in two of the rooms under 16‐h photoperiods. Birds maintained under an 8‐h photoperiod matured 11.25 day later than those maintained under a 16‐h photoperiod (p < 0.05). The group of birds receiving 20 mg/kg MEL matured 1.19 day later than those maintained under the 16‐h photoperiod and 10.06 day earlier than those maintained under the 8‐h photoperiod. The group of birds receiving 200 mg/kg MEL matured 3.13 day later than those maintained under a 16‐h photoperiod and 8.12 day earlier than those maintained under an 8‐h photoperiod. The average body weight of birds maintained under the 8‐h photoperiod was greater than that of birds maintained under the 16‐h photoperiod (p < 0.05) and was similar between the different MEL groups. The abdominal fat weight was lower in 16L:8D group compared with 8L:16D group (p < 0.05). The concentrations of follicle‐stimulating hormone, luteinizing hormone, oestrogen and insulin did not differ significantly among the groups. The melatonin concentration in 200 mg/kg melatonin group was higher than that observed in the other groups; however, this concentration did not differ significantly (p > 0.05). These data suggest that the birds did not perceive the final 8‐h photoperiod as being part of the night when they were given the MEL diets; continuously high plasma MEL was not observed in birds that responded as if they were in constant darkness. However, the later maturity of the groups administered MEL diets compared with the groups maintained under a constant 16‐h photoperiod clearly indicated that MEL has some influence on the sexual maturity of pullets.  相似文献   

13.
Relationships among plasma hormonal and metabolic variables in the last trimester of gestation in 59 Piedmontese dams (n = 15 heifers, n = 44 cows) and the calf birth weight (BWT) class of their offspring were investigated in seven herds. The BWT data were categorized as follows: > 50 kg (BWT-A), 46 to 50 kg (BWT-B), 41 to 45 kg (BWT-C), and < 41 kg (BWT-D). Blood samples were collected at 33, 36, and 39 wk of gestation. Packed cell volume (PCV) and plasma concentrations of insulin, estrone sulfate (E1SO4), NEFA, and creatinine were determined and correlated to BWT class. Creatinine: E1SO4 ratio also was calculated. Duration of gestation was greater for dams producing a BWT-A calf than for the other BWT classes, and calf BWT was heavier (P < 0.001) for calves in the BWT-A vs. BWT-D class. The heaviest calf in BWT-A was associated with the highest calving difficulty score. Insulin and PCV values were not affected by week of gestation, whereas plasma E1SO4, NEFA, and creatinine content increased (P < 0.001) and creatinine:E1SO4 decreased (P < 0.001) during late gestation. Calf BWT class did not affect PCV value. Plasma E1SO4 concentrations were lower (P < 0.01) in BWT-D dams than the other dams, showing the greatest difference at 39 wk of gestation. At 36 and 39 wk of gestation, dams bearing BWT-C and BWT-D calves had a higher (P < 0.01) plasma insulin concentration than those bearing BWT-A and BWT-B calves. Plasma NEFA concentrations at 39 wk of gestation were higher (P < 0.05) in dams of calf BWT-A than in the other dams. We conclude that plasma E1SO4 level is a variable that can be used to monitor problems related to a small size calf. Conversely, the forthcoming birth of a calf with a heavy BW seems to be preceded by a pronounced increase in plasma NEFA level in the dam just a few days before calving.  相似文献   

14.
The objective of the present research was to evaluate the effect of a calf's genetic group on the productive and reproductive efficiency of its Nellore dam. Fixed‐time artificial insemination was applied to 800 cows using semen extracted from Nellore, Simmental and Angus Red bulls. Four hundred eleven cows calved, producing 119 Nellore, 103 ½Simmental–½Nellore and 189 ½Nellore–½Angus Red calves. The second mating period, which paired Nellore cows with Simmental bulls, was initiated 10 days after parturitions began and lasted for 5 months. Based on the two successive parturitions, the cumulative parturition rate for calving periods of 3, 4 and 5 months was calculated. Although no significant difference was observed for birth weight among the genetic groups, cross‐bred calves weighed, on average, 10% more than did pure‐bred calves at the age of 205 days. Nellore dams experienced a gestation period that was 7 days longer than did the cross‐bred dams, and the former showed a higher parturition rate at 90 and 120 days of the calving season, but not at 150 days (calving rates of 80.6, 76.4 and 76.2% for mothers of Nellore, ½Nellore–½Angus Red and ½Nellore–½Simmental, respectively, p > 0.05). At 90 and 120 days, Nellore dams produced more kg of calf per mated dam. In conclusion, in a short breeding season, Nellore dams nursing pure‐bred Nellore calves were found to have a higher biological efficiency compared with Nellore dams nursing cross‐bred calves.  相似文献   

15.
A study was conducted to assess the growth performance and nutrient utilization of cross‐bred calves serially infected with Fasciola gigantica and/or supplemented with deoiled mahua seed cake (DMSC) during pre‐patent period of infection. Twenty healthy cross‐bred (Holstein Friesian × Haryana) male calves aged 6–7 months with an initial average live weight of 79.6 ± 2.71 kg were divided into four treatment groups (CON, CON‐INF, DMC and DMC‐INF) of five animals each following randomized block design. DMSC was included in the concentrate mixture of DMC and DMC‐INF groups at 100 g/kg level. Animals of groups CON‐INF and DMC‐INF were given an infection of 200 metacercariae (mc) of F. gigantica as serial infection dose of 50 mc twice weekly over a period of 2 weeks. A metabolism trial at 40–49 days post‐infection and growth trial of 145 days duration were conducted. The average daily gain (ADG) and feed conversion ratio (FCR) were significantly (p < 0.05) lower in CON‐INF group as compared to others. The ADG and FCR were significantly (p < 0.05) higher in DMC‐INF as compared to CON‐INF. The intake and digestibility of nutrients were not affected by serial infection with F. gigantica during pre‐patent period. However, significantly (p < 0.001) higher urinary excretion and significantly (p < 0.001) lower nitrogen balance were observed in CON‐INF group as compared to other three groups. The nitrogen balance was significantly (p < 0.001) improved in DMC‐INF group as compared to CON‐INF group. From the results, it may be deduced that the supplementation of deoiled mahua seed cake at 100 g/kg level in the concentrate mixture has improved the growth performance and nitrogen utilization in cross‐bred calves infected with F. gigantica.  相似文献   

16.
The main objective of this study was to determine if administration of meloxicam, a cyclooxygenase (COX) two inhibitor, to heifers in which embryo transfer (ET) is more difficult and requires a greater manipulation of the tract, would be beneficial. Nulliparous recipient heifers were divided in two groups: CON (n = 102), in which animals received 10 ml of saline IM (the same volume of meloxicam) and MEL (n = 105) animals that were treated with meloxicam. According to the degree in passing the catheter, recipients from both groups were classified as Grade I, easy (< 60 s), and Grade II (more than 80 s), difficult. Immediately after embryo transfer, MEL recipients received an injection of 200 mg of meloxicam (10 ml).There was no difference in the pregnancy rates on Day 35 considering animals which presented Grade I cervix independently whether the treatment was performed or not (p = 0.22). There was a statistical difference in the pregnancy rates (p < 0.01) between both groups (49.0% and 66.7% for CON and MEL, respectively) when cervical grade was not considered, on Day 35. Considering the animals that presented Grade II cervix, the pregnancy rate was higher for MEL (21.15% and 78.84%, respectively) in both examinations (p < 0.01).The authors concluded that meloxicam had a positive influence on general pregnancy rate of treated heifers in comparison to non‐treated heifers. It was also observed that pregnancy rate was not influenced by meloxicam administration in Grade I heifers. Treatment increased the pregnancy rate of Grade II heifers.  相似文献   

17.
Potential vertical transmission of wild-type bluetongue virus serotype 8 (BTV-8) in cattle was explored in this experiment. We demonstrated transplacental transmission of wild-type BTV-8 in one calf and oral infection with BTV-8 in another calf. Following the experimental BTV-8 infection of seven out of fifteen multi-parous cows eight months in gestation, each newborn calf was tested prior to colostrum intake for transplacental transmission of BTV by RRT-PCR. If transplacental transmission was not established the calves were fed colostrum from infected dams or colostrum from non-infected dams spiked with BTV-8 containing blood. One calf from an infected dam was born RRT-PCR positive and BTV-specific antibody (Abs) negative, BTV was isolated from its blood. It was born with clinical signs resembling bluetongue and lived for two days. Its post-mortem tissue suspensions were RRT-PCR positive. Of the seven calves fed colostrum from infected dams, none became infected. Of the six calves fed colostrum from non-infected dams spiked with infected blood, one calf became PCR-positive at day 8 post-partum (dpp), seroconverted 27 days later, and remained RRT-PCR and Abs positive for the duration of the experiment (i.e., 70 dpp). This work demonstrates that transplacental transmission in late gestation and oral infection of the neonate with wild-type BTV-8 is possible in cattle under experimental conditions.  相似文献   

18.
The effects of supplementing ewe diets with either DL‐methionine (DL‐Met) or 2‐hydroxy‐4 (methylthio) butanoic acid isopropyl ester (HMBi) were investigated on ruminal in situ degradability of grain and forage diets, in vivo digestibility, rumen fermentation, blood metabolites and antioxidant status. Six ruminally cannulated ewes were used in a replicated 3 × 3 Latin square design with 28‐day periods. The dietary treatments were as follows: (i) no supplemental Met (control; CON), (ii) DL‐Met at 1.2 g/kg DM intake and (iii) HMBi at 1.8 g/kg dry matter (DM) intake. Corn grain, barley grain and alfalfa hay were evaluated for their ruminal degradability by both in situ incubation and effective degradability measurements of DM, neutral detergent fibre (NDF) and acid detergent fibre (ADF). Compared to other treatments, HMBi supplementation increased (p < 0.05) the digestibility of organic matter, crude protein and NDF and also tended (p = 0.08) to increase the digestibility of DM and ADF. Moreover, HMBi supplementation increased (p < 0.01) total VFA concentrations, the molar proportions of valerate and iso‐butyrate in the rumen. Compared to the CON treatment, DL‐Met and HMBi treatments tended (p = 0.08) to increase the molar proportion of acetate but decreased (p < 0.05) ruminal ammonia‐N concentration. Ewes supplemented with HMBi and DL‐Met recorded greater (p < 0.05) serum concentrations of glutathione peroxidase, total antioxidant capacity and superoxide dismutase than the CON treatment. Serum concentrations of glucose, total protein, albumin, high‐density lipoprotein and very low‐density lipoprotein were greater (p < 0.01) and serum urea nitrogen (p < 0.05), malonyl dialdehyde and triglyceride were lower (p < 0.02) in the HMBi and DL‐Met animals than in the CON ewes. The results concluded that HMBi is a very effective form of dietary Met supplementation for ewes with a positive effect on digestion, rumen fermentation and serum antioxidant function.  相似文献   

19.
The objectives of this study were to determine the effect of parity of the dam on age at which a scrotal circumference (SC) ≥ 28 cm was attained and the LH response to Luteinizing Hormone Releasing Hormone (LHRH) in bull calves. We also wanted to confirm, in a large group of bull calves, that the LH response to LHRH could be used to select early maturing bulls. Body weight and SC of the bull calves were measured every other week. At 15, 20 and 25 weeks of age, calves received 4.12 nm /kg body weight of LHRH ischio‐rectally and blood samples were taken every 15 min for 4 h. Calves from primiparous and multiparous dams were separated into two sub‐groups based on age at which an SC ≥ 28 cm was attained (early or late). An SC ≥ 28 cm was attained earlier in calves born to multiparous as compared with primiparous dams (p < 0.05). At 20 and 25 weeks of age, peak serum LH concentrations (LH‐peak) and area under the LH response curve (LH‐AUC) in response to LHRH were higher (p < 0.01) in calves born to multiparous as compared with primiparous dams. In calves born to multiparous dams the LH‐peak at 15 and 25 weeks of age and the LH‐AUC at 15 weeks of age were lower (p < 0.05) in calves that attained an SC ≥ 28 cm early as compared with late. The LHRH‐challenge test sensitivity and specificity ranged from 46% to 86%. We concluded that parity of the dam affected age at which SC ≥ 28 cm was attained and the LH response to LHRH in bull calves. Serum LH responses to LHRH at 15 and 25 weeks of age, in calves born to multiparous dams, show some promise for development into a test to select early maturing bull calves.  相似文献   

20.
The study aimed to investigate the effects of maternal dietary methyl donors on the performance of sows and their offspring, and the associated hepatic insulin‐like growth factor‐1 (IGF‐1) expression of the offspring. A total of 24 multiparous sows were randomly fed the control (CON) or the CON diet supplemented with methyl donors (MD) at 3 g/kg betaine, 15 mg/kg folic acid, 400 mg/kg choline and 150 μg/kg VB12, from mating until delivery. After farrowing, sows were fed a common lactation diet through a 28‐days lactation period and six litters per treatment were selected to be fed until at approximately 110 kg BW. Maternal MD supplementation resulted in greater birthweight (p < 0.05) and increased the piglet weights (p < 0.01) and litter weights (p < 0.05) at the age of day 28, compared with that in CON group. The offspring pigs in the MD group had greater ADG (p < 0.05) and tended to lower F:G ratio (p = 0.07) compared with that of CON group from day 28 to 180 of age. The offspring pigs from MD group had greater serum IGF‐1 concentrations and expressions of hepatic IGF‐1 gene and muscular IGF‐1 receptor (IGF‐1r) protein at birth (p < 0.05), and greater hepatic IGF‐1 protein (p = 0.03) and muscular IGF‐1r gene expressions (p < 0.05) at slaughter, than that from the CON group. Moreover, the methylation at the promoter of IGF‐1 gene in the liver of newborn piglets and finishing pigs was greater in the MD group than that of the CON group (p < 0.05). In conclusion, maternal MD supplementation throughout gestation could enhance the birthweight and postnatal growth rate of offspring, associated with an increased expression of the IGF‐1 gene and IGF‐1r, as well as the altered DNA methylation of IGF‐1 gene promotor.  相似文献   

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