Production Performance Of Dairy Cows Research Articles

Ruminal degradability, feeding behavior and production performance in dairy cows fed ear corn silage

Ruminal degradability, feeding behavior and production performance in dairy cows fed ear corn silage

EFFECT OF LONG CHAIN FATTYACIDS ON THE PRODUCTION AND REPRODUCTIVE IMMUNITY OF HOLSTEIN DAIRY COWS

Twenty two multiparous and primiparous Holstein cows were utilized in a completely randomized design to determine the effects of feeding diets containing health, immunity, reproductive responses of heat stressed cows during the transition period. Dietary treatments were initiated 20-35 d prior to estimate calving date and continued till confirmed pregnancy postpartum. Diets were formulated to be isocaloric and isonitrogenous and started feeding the pre calving diets at July for the precalving cows and the post calving diets were fed tell conception. Dry matter intake (DMI) was measured and recorded , the average 1 three months postpartum milk production were calculated. Total mixed ration (TMR) ration were collected monthly , and analyzed. Milk samples were collected for analysis and measuring beta hydroxy buterate (BHB), lysozy me and nitric oxide concentration .The obtained results showed no difference in the average DMI between the two group sin pre calving stage (12.5for G1;12.4 for G2,Kg/h/d),while, it was higher in theG1(20.55) than in G2 (18.45) in the 1st three month post calving. Milk production was increased in G1(36.42±0.14kg)than in G2 (34.57±0.20kg) but they are not significantly different. Also there was no significant difference between the two groups in milk analysis for protein, fat, SNF, and lactose at W2, W4 and at W7 postpartum. BHB concentration at W2 PP was significantly lower in G1 (25±9.45µg/mol.) than those in G2 (81.25±9.15µg/mol.) , lysozyme at w2, w4 and w7 PP was significantly decreased in G1(94.10±30.73,45.56±9.86,26.15±11.12µg/ml) than those in G2 (246.34±6.11, 217.21±9.56, 192.68±11.048µg/ml) respectively. Nitric oxide concentration was significantly decreased in G1 (47.38±18.21, 18.43±3.45, 14.27±2.72 µm/ml) than those in G2 (91.79±9.55, 64.73±7.40, 42.53±6.31µm/ml) at W2,W4 and W7, respectively. Uterine cytology (neutrophil concentration) at day40±3PP was higher in G2 than G1 but they were not significantly different. Days to1st estrus and days to1st insemination were significantly lower in group one (36.92±0.52, 75.0793±0.68) than those in G2 (86.18±0.64, 88.94±0.53) respectively. Days open and I.N. in G1 (172.89±3.13, 3.19±0.06) were lower than those in G2(195.42±2.78,4.07±0.07) but they were not significantly different. Conception rate(CR%) at1st, 2nd and 3rdinsemination was higher in G1 (10%,50%,20%) than those in G2(8.33%,25%,8.33%) and also repeat breeder (%) was much greater in G2(58.33%) than in G1 (30%). This study concluded that, using omega-3FA may enhance there productive performance of dairy cows during summer season because of its anti-inflammatory potency, leading to a higher chance of survival of the embryo when supplemented during the per conceptual period by reducing the oxidative stress.

Use of 3-nitrooxypropanol as feed additive for mitigating enteric methane emissions from ruminants: a meta-analysis

This study aimed to perform a meta-analysis on the effect of 3-nitrooxypropanol (3-NOP) on enteric methane (CH4) emissions from ruminants. A total of 12 in vivo studies from 10 articles were integrated into a database. Ruminant species included were dairy cows, beef cattle and sheep. Concentration of 3-NOP in diets varied from 0 to 280 mg/kg dry matter intake (DMI). Parameters included were CH4 emissions, rumen fermentation, microbial population, nutrient digestibility and animal performance. Meta-analysis of data was performed by using mixed model methodology in which different studies were treated as random effects whereas 3-NOP addition levels in diets of ruminants were treated as fixed effects. Results showed that increasing level of 3-NOP addition in diets of ruminants decreased enteric CH4 emissions per unit of body weight, CH4/DMI, CH4/milk produced, CH4/digested organic matter or CH4/gross energy intake (p < .05). Production of H2 was higher with increasing level of 3-NOP addition (p < .001). Addition of 3-NOP decreased total VFA concentration (p < .01), and decreased and increased proportions of C2 and C3, respectively (p < .001). Addition of 3-NOP decreased archaea population (p < .01) but it did not change total bacteria and protozoa populations. The substance had minor effect on digestibility of nutrients. Production performance of dairy cows and beef cattle was limitedly influenced by the addition of 3-NOP in the diets, and it had no negative effect on DMI of ruminants. It is concluded that 3-NOP is an effective feed additive to mitigate enteric CH4 emissions without compromising productive performance of ruminants.

Role of niacin supplementation in dairy cattle: A review

Niacin (Vitamin B3) is significantly important for the metabolism of animals and human beings due to its incorporation into the coenzymes NAD and NADP. For dairy cows, the microbial synthesis of niacin in the rumen is an important source besides its availability from feed and endogenous formation. This vitamin is involved in various energy-yielding pathways and for synthesis of amino acid and fatty acid; for which it is important for milk production. Supplementation of niacin has beneficial effects on growth of cattle. The production performance of dairy cows fed with niacin at 6g/day may not be satisfactory, but supplementation of 12g of niacin per head per day can increase milk production by about 1lb. An optimistic return on asset is possible if the supplementation is limited to high producing early lactation cows. Supplementing the dairy animals with a dose of 6-12g of niacin will not only protect them from various metabolic diseases but will also help them defend from severe heat stress; ultimately leading to augmentation of their health, production potential and economy.

Energy and tannin extract supplementation for dairy cows on annual winter pastures

Energy supplementation can increase the consumption of metabolizable energy and substrate for microbial growth, while condensed tannins aid in increasing the duodenal flow of foodborne metabolizable proteins. The objective of this study was to evaluate the effects of energy supplementation and the inclusion of tannin extract (TE) from Acacia mearnsii (Weibull Black, Tanac S. A., Montenegro, Brazil) on the production performance of dairy cows grazing on winter pastures. Nine multiparous Holstein cows in mid lactation were distributed in a 3 × 3 Latin square experimental design over three periods of 28 days (21 adaptation and 7 sampling). The treatments were: without supplementation (WS), supplementation with 4 kg of corn grain (CG), and corn grain + 80 g of tannin extract (TE). The dry matter (DM) intake from pastures was similar among treatments, but the consumption of DM of the supplement was higher in the CG treatment than that in the TE treatment. The total DM intake was higher for the supplemented animals (17.3 kg?day-1) than that for the unsupplemented animals (14.9 kg?day-1) and in the TE treatment (17.7 kg?day-1) than in the CG treatment (16.7 kg day-1). Milk production increased from the unsupplemented to the supplemented animals (20.9 to 23.5 kg, respectively), while the content of urea N in the milk decreased (12.6 to 10.5 mg?100 mL-1, respectively). There were no differences in milk production or content of milk urea N between the CG and TE treatments. Energy supplementation is a tool for improving the nutritional profile and the performance of dairy cows in mid lactation grazing on annual winter pastures, while tannin extract aids in improving the energy balance.

Effect of Supplementing Area Specific Mineral Mixture on Productive Performance of Crossbred Cows

The study examined the efficacy of supplementing area specific mineral mixture on nutrient utilization and productive performance of lactating crossbred cows. Twenty lactating cows with average lactation yield of 2100 L and average days after calving of 95 were selected from the local dairy farms in village Lohali, Majhera in the vicinity of mid hills of Uttarakhand state and randomly divided into two groups of 10 each (T1-control; T2-experimental). The area specific mineral mixture (@ 2% of concentrate mixture) was supplemented in T2 group while the roughage source for animals in both the groups was oak tree leaves. The concentrate and roughage ratio was maintained at about 40: 60 level. A digestibility trial of six days duration was conducted at the end of experimental feeding i.e. 90 days. DM intake, milk yield and milk composition were recorded at fortnightly intervals. Average daily DM intake (kg/d) was not influenced by mineral mixture supplementation with values of 11.40 and 12.16 in control and treatment group, respectively. Nutrient digestibility of CP, EE and NDF was higher (P<0.05) in area specific mineral mixture supplemented animals than control group. Supplementation of area specific mineral mixture improved the mineral status of the animals as reflected in improved serum minerals level. The milk yield increased by 9.5% and FCM yield by 11.8%. It was concluded that dietary supplementation of area specific mineral developed for hills of Uttarakhand improved nutrient utilization, mineral bioavailability and milk production performance in dairy cows fed oak leaves based diet.

Status of Assisted Reproductive Technologies for Genetic Improvement of Dairy Cattle in Ethiopia: Review

This review is aimed to summarize and synthesize the fragmented information on effectiveness of assisted reproductive technologies (ARTs) for enhancing genetic improvement of dairy cattle in Ethiopia. Like most developing countries, artificial insemination (AI) is the first and most commonly used ARTs in Ethiopia because of its relative simplicity. It had been applied for nearly fifty years. In order to enhance efficiency of AI service and improve heat detection problem of the dairy farmers, oestrous synchronization and mass artificial insemination (OSMAI) had also triggered as second reproductive technology and management. Even though the conception rate of conventional AI service which was 27 % improved to 39.3% for hormone treated dairy cows, the total number of cross breed cattle is only 705,526 (1.22%) from 57.83 million cattle population of the country. Furthermore, currently, the average milk yield per cow per day at country level is about 1.37 liters and the average lactation period per cow is estimated to be about six months. This indicates that the access of genetically improved dairy cows for smallholder farmers and the reproductive and productive performance of dairy cows have continued with little change from natural mating. The main reasons for this insignificant change were interrupted AI service delivery system, discrepancy between time of heat detection and appropriate time of insemination, shortage of AITs and low output from the available technicians, lack of appropriate collaborations between service provider and other stakeholders and absence of herd recording system. In order to improve the effectiveness of the technologies and ultimately enhance access of smallholder farmers for improved dairy cattle, emphasis should be given on identified problems.

Effect of feeding of different sources of NPN on production performance of dairy cows

Received: 2016-04-11 | Accepted: 2016-05-04 | Available online: 2016-12-22 http://dx.doi.org/10.15414/afz.2016.19.04.163-166 The aim of the study was to analyse the effect of feeding of different sources of NPN on nutrient utilization and production performance of dairy cows under field conditions. Balancing diets for crude protein without consideration of protein quality or rumen degradability often led to overfeeding of nitrogen and less than optimum production. High yielding dairy cows separated in two groups with 85 resp. 80 cows in each were set up for the trial. Groups were consistent according the stage of production and reproduction cycle as well as age structure. Both groups were fed concentrate mixture with the same composition with only difference in NPN/ microbial protein source, with same dosage of 100 g per cow and day. Field trial was performed for period of 3 subsequent months. Performance data were collected in accordance with official milk recording. In both groups majority of cows were on first lactation. Significant differences in daily milk production were observed 2.87 kg (P<0.01) for group 2, in fat content 0.07 % for group 2 non-significant, whereas in protein content 0.18% for group 1 significant (P<0.01) in case of first lactations. If considering first tree lactations, group 2 produced 1.7 kg milk per day more (P<0.08), with 0.05% fat more and 0.002 % protein less than group 1. The space created in dry matter intake by a concentrated slow-release NPN can be filled with high quality forage that could reduce the cost of feeding while maintaining levels of production. Keywords: Holstein, slow-release urea, microbial protein, milk yield References Biro, D., Galik, B., Juracek, M. et al. (2009) Effect of Biological and Biochemical Silage Additives on Final Nutritive, Hygienic and Fermentation Characteristics of Ensiled High Moisture Crimped Corn. Acta Veterinaria Brno , vol. 78 (4), pp. 691-698 doi: http://dx.doi.org/10.2754/avb200978040691 Bouska J. et al. (2006) Chov dojeneho skotu, Profi Press, Praha , 2006 Cantalapiedra-Hijar, G., Peyraud, J. L., Lemosquet, S. et al. (2014) Dietary carbohydrate composition modifies the milk N efficiency in late lactation cows fed low crude protein diets. Animal , vol. 8 (2), pp. 275-285 doi: http://dx.doi.org/10.1017/S1751731113002012 Cappellozza, B. I., Bohnert, D. W., Schauer, C. S. et al. (2013) Daily and alternate day supplementation of urea or soybean meal to ruminants consuming low-quality cool-season forage: II. Effects on ruminal fermentation Livestock Science , vol. 155 (2-3), pp. 214-222 doi: http://dx.doi.org/10.1016/j.livsci.2013.05.002 De Boever, J. L., Blok, M. C., Millet, S. et al. (2014) The energy and protein value of wheat, maize and blend DDGS for cattle and evaluation of prediction methods. Animal , vol. 8(11), pp 1839–1850 doi: http://dx.doi.org/10.1017/S1751731114001815 Harrison, G. A. and Karnezos T. P. (2005) Can we improve efficiency of nitrogen utilization in the lactating cow? Recent Advances in Animal Nutrition , vol. 15, 2005, 001-011pp. Hazuchova E. and Kasarda R. (2010) Evaluation of body condition score of lactating cows. 61st EAAP Annual Meeting, Heraklion. 2010 . Book of Abstracts. 34, 26,p. 375 Holder Vaughn B., El-Kadi, Samer W., Tricarico, Juan M. et al. (2013) The effects of crude protein concentration and slow release urea on nitrogen metabolism in Holstein steers. Archives of Animal Nutrition , vol. 67 (2), pp. 93-100 doi: http://dx.doi.org/10.1080/1745039X.2013.773647 Kudrna V. and Homolka P. (2009) Vliv diety, zejmena obsahu dusikatých latek, na množstvi a kvalitu mlecne bilkoviny a zdravi dojnic, Výskumný ustav živocisne výroby, Praha – Uhřiněves, 2009 McGuire D. L., Bohnert, D. W., Schauer, C. S. et al. (2013) Daily and alternate day supplementation of urea or soybean meal to ruminants consuming low-quality cool-season forage: I-Effects on efficiency of nitrogen use and nutrient digestion Livestock Science , vol. 155, (2-3), pp. 205-213 doi: http://dx.doi.org/10.1016/j.livsci.2013.05.015 Simko, M., Ceresňakova, Z. Biro, D. et al. (2010) Influence of Wheat and Maize Starch on fermentation in the Rumen, Duodenal Nutrient Flow and Nutrient Digestibility. ActaVeterinaria Brno , vol. 79 (4), pp. 533-541 doi: http://dx.doi.org/10.2754/avb201079040533 Zeman, L. et al.(2006) Výživa a krmeni hospodařských zviřat., Profi Press, Praha , 2006

Potassium carbonate as a cation source for early-lactation dairy cows fed high-concentrate diets

Previous studies reported that addition of K2CO3 to high-concentrate diets improved milk fat synthesis, although the mechanism is yet to be established. The objective of the current experiment was to investigate the effects of dietary cation-anion difference (DCAD), cation source, and buffering ability of the mineral supplement on rumen biohydrogenation of fatty acids and production performance in dairy cows fed a high-concentrate diet. Thirty-five early-lactation Holstein cows (25 multiparous ruminally fistulated and 10 primiparous nonfistulated) were used in a randomized complete block design (7 blocks) with 33-d periods, including a 5-d pre-treatment collection period used as a covariate. Diets were (1) control, a basal diet [47% nonfibrous carbohydrates, DCAD (Na + K - Cl - S) = 65 mEq/kg of dry matter (DM)] containing 40% forage (including 60% corn silage) and 60% concentrate, (2) K2CO3 (control + K2CO3, 1.8% of DM, DCAD = 326 mEq/kg of DM), (3) KHCO3 (control + KHCO3, 2.6% of DM, DCAD = 324 mEq/kg of DM), (4) KCl (control + KCl, 2.0% of DM, DCAD = 64 mEq/kg of DM), and (5) Na2CO3 (control + Na2CO3, 1.4% of DM, DCAD = 322 mEq/kg of DM). Pre-planned orthogonal contrasts were used to assess the effects of K2CO3 (control vs. K2CO3), buffering ability (K2CO3 vs. KHCO3), DCAD (K2CO3 vs. KCl), and cation type (K2CO3 vs. Na2CO3). Supplementing K2CO3 in a high-concentrate diet did not improve milk fat yield or 4% fat-corrected milk yield. Milk fat concentration was greater in cows fed K2CO3 compared with control (4.03 vs. 3.26%). Milk yield tended to decrease (34.5 vs. 38.8 kg/d) and lactose yield decreased in cows fed K2CO3 as compared with KCl (1.64 vs. 1.87 kg/d). Milk fat concentration of trans-10 18:1 was increased when cows were fed Na2CO3 as compared with K2CO3. A positive relationship was observed between concentrations of anteiso 15:0 and trans-10,cis-12 18:2 in milk fat from cows receiving K2CO3. Milk Na concentration was increased, whereas milk Cl was decreased with K2CO3 as compared with KHCO3 or KCl. A positive relationship was established between milk Cl concentration and milk yield (R2 = 0.34) across all dietary treatments. Cation-anion difference (Na + K - Cl - S) in ruminal fluid was increased with K2CO3 as compared with control or KCl. Blood pH tended to decrease in cows fed KCl compared with K2CO3. Our results suggest that mineral supplementation tends to affect milk and milk fat synthesis and that factors other than DCAD, potassium ion, or buffer ability may be implicated. The variations observed in mineral composition of milk suggest an allostatic process to maintain an ionic equilibrium in mammary epithelial cells in response to mineral composition of the diet.

Reproductive and Lactation Performance of Crossbreed Dairy Cows in Bishoftu, Ada’a Distict of East Shoa, Eastern Ethiopia

For several years, Ethiopia ranked first in cattle population in Africa. However, the dairy industry is not as developed as that of East African countries including Ethiopia. This study was conducted to assess the reproductive and lactation performance and factors affecting crossbreed dairy cattle in intensive dairy farm in Bishoftu, Ada’a district of Ethiopia. A total of 215 dairy cows’ data were recruited for the study from Ethiopian meat and dairy industry development institute from 2008-2014 data records on 4 upgraded genetic groups of crossbreeds (50% Friesian x 50% Borana F 1 75% Friesian x 25% Borana F 2 , 87.5% Friesian x 12.5% Borana F 3 , 93.75% Friesian x 6.25% BoranaF 4 ). The traits studied were age at first service (AFS), age at first calving (AFC), calving interval (CI), number of service per conception (NSPC), dry period (DP), lactation length (LL) and milk yield per lactation (MYPL). It was revealed that the mean age at 1st service (23.7±4.08months) and mean age at 1 st calving (33.36±4.6months) of F 4 were lower (p 0.05). The lowest number of service per conception (1.2±0.34) was determined from F 2 as compared to other genetic groups with statistically difference (p 0.05). Comparatively, highest mean for lactation length and milk yield per lactation recorded from F 4 were 12.68±3.12months and 3579±842 litters, respectively with the absence of statistically difference (p>0.05). In short, the overall mean values for AFS, AFC, CI and NSPC were 24±4.16, 34.6±5.37, 14.64±2.2 and 1.35±0.423 months, respectively was observed. Also the overall mean values for DP, LL and MYPL were 81.32±18.671days, 11.96±2.5months and 3386.22±898.719litters obtained in this finding. Generally, good reproductive and lactation of performances were recorded during this study and the reproductive and productive performance of dairy cows still needs better management practices, improved nutrition and use of new reproductive technology for more improvement.

Fetal sex influence in the productive performance of dairy cows

Investigating factors that could affect milk production of cows is an important way to improve the efficiency of production systems. This purpose of this study was to verify and quantify the influence of calf sex on milk production and lactation length in herds of Holstein, Gir, and Guzera cows. Data from 10,780 lactations of 4,807 Holstein cows that calved between 2001 and 2013; 18,898 lactations of 13,172 Gir cows that calved between 1985 and 2013; and 5,277 lactations of 3,972 Guzera cows that calved between 1987 and 2013 were used. Both the accumulated 305-day milk yield (P305) and the length of the lactation period up to 305 days (DL305) were evaluated. Analysis of variance was performed by the least squares method using the GLM procedure in the SAS statistical program. The P305 was not influenced by the sex of the calf in the Holstein breed. However in the zebu breeds (Gir and Guzera), both P305 and DL305 were significantly affected (P &amp;lt; 0.01) by the sex of the calf, with higher production and average length of lactation in cows that calved males. In addition, a significant difference was also nested within sex of calf and age at first calving (P &amp;lt; 0.05) in the Gir breed. The results indicate that for the zebu breeds, calf sex influences production characteristics.

Nutritional and productive performance of dairy cows fed corn silage or sugarcane silage with or without additives.

The objective of this study was to compare the intake, digestibility, and performance of dairy cows fed corn silage, fresh sugarcane, and sugarcane ensiled in three different forms. Twenty-five Holstein cows at 114 ± 12.6 days in milk (DIM) were used. A randomized block design was adopted, using an arrangement of repeated measures over time. The following treatments were tested: corn silage (CS); fresh sugarcane (FS); sugarcane silage without additives (SCS); sugarcane silage enriched with calcium oxide at 5 g/kg of forage (SCSc); and sugarcane silage enriched with Lactobacillus buchneri at 5 × 10(4) cfu/kg of forage (SCSb). The roughage to concentrate ratio was 60:40 for the CS diet and 40:60 for the sugarcane-based diets. The dry matter intake (DMI) as a function of body weight had a downward trend for the cows fed sugarcane silage, compared with those fed FS. The sugarcane silages had higher digestibilities of dry matter (DM), organic matter (OM), and neutral detergent fiber (NDFap), compared with FS. The use of L. buchneri or calcium oxide improved the diet's digestibility. The use of FS, sugarcane silage, or sugarcane silage with additives had no effects on milk and fat-corrected milk yield, compared to corn silage. Cows fed FS presented lower milk total solids content and had a downward trend for milk fat, compared with cows fed sugarcane-silage diets. Cows fed sugarcane silages produced milk with higher casein stability in the alcohol test than cows fed fresh-sugarcane diet. Sugarcane silage, with or without additives, did not reduce the intake of dairy cows, and the use of additives improved the fiber's digestibility.

Effects of rutin and buckwheat seeds on energy metabolism and methane production in dairy cows

Flavonoids are secondary plant metabolites with several health promoting effects. As dairy cows often suffer from metabolic imbalance and health problems, interest is growing in health improvements by plant substances such as flavonoids. Our group has recently shown that the flavonoids quercetin and rutin (a glucorhamnoside of quercetin) are bioavailable in cows when given via a duodenal fistula or orally, respectively, affect glucose metabolism, and have beneficial effects on liver health. Furthermore, flavonoids may reduce rumen methane production in vitro through their antibacterial properties. To test the hypothesis that rutin has effects on energy metabolism, methane production, and production performance in dairy cows, we fed rutin trihydrate at a dose of 100mg/kg of body weight to a group of 7 lactating dairy cows for 2wk in a crossover design. In a second experiment, 2 cows were fed the same ration but were supplemented with buckwheat seeds (Fagopyrum tartaricum), providing rutin at a dose comparable to the first experiment. Two other cows receiving barley supplements were used as controls in a change-over mode. Blood samples were taken weekly and respiration measurements were performed at the end of each treatment. Supplementation of pure rutin, but not of rutin contained in buckwheat seeds, increased the plasma quercetin content. Methane production and milk yield and composition were not affected by rutin treatment in either form. Plasma glucose, β-hydroxybutyrate, and albumin were increased by pure rutin treatment, indicating a possible metabolic effect of rutin on energy metabolism of dairy cows. In addition, we did not show that in vivo ruminal methane production was reduced by rutin. In conclusion, we could not confirm earlier reports on in vitro methane reduction by rutin supplementation in dairy cows in established lactation.

Effect of puerperal metritis on reproductive and productive performance in dairy cows in Argentina

The objectives of this study were to evaluate the reproductive and productive performance of dairy cows with and without puerperal metritis and to evaluate the effectiveness of using a long-acting ceftiofur preparation. Dairy cows in one dairy farm, calving from July 2009 to January 2010, were examined between 3 and 14 days postpartum and classified on the basis of vaginal discharge into three groups: cows with normal discharge (control; C); cows with a bloody mucus purulent or pathologic nonfetid discharge (PnFD), and cows with bloody mucopurulent or purulent fetid discharge (PFD). Cows in C and PnFD groups were not treated, whereas those in the PFD group were randomly allocated to receive 2.2 mg/kg of ceftiofur subcutaneously behind the ear (PFD-T) or remain untreated (PFD-No T). From the 640 cows examined, 58.2% formed the C group, 13.4% formed the PnFD group, and 28.4% formed the PFD group. Survival curves differed between cows in the C group and PFD-No T group (P = 0.0013) and between PFD-No T versus PFD-T group (P = 0.0006). Survival curves of PnFD were intermediate and did not differ from those in the C group (P = 0.2) and PFD-T group (P = 0.1) but tended to be different from the PFD-No T group (P = 0.056). The postpartum interval to achieve a 25% pregnancy rate was 72 days for cows in the C group, 73 days for the PFD-T group, 83 days for PnFD group, and 95 days for the PFD-No T group. The chance of pregnancy in a cow in the C group was 1.98 times higher (95% confidence interval = 1.33, 3.08) and in cows in the PFD-T group was 2.16 times higher (95% confidence interval = 1.37, 3.50) than that in the PFD-No T group. Finally, the chance of pregnancy in cows in the PnFD group tended to be higher (P = 0.08) than that in the PFD-No T group but did not differ from the other two groups. Cumulative 305-day milk production was higher (P < 0.0001) in C group than those with vaginal discharge, regardless of fetidness and regardless of treatment. It is concluded that puerperal metritis affects the reproductive and productive performance of dairy cows and the treatment with ceftiofur was effective in reducing the adverse effects on reproductive performance but not on milk production.

Productive performance of dairy cows fed with hydrolyzed sugarcane

This study aimed to evaluate the productive performance of dairy cows fed with sugarcane treated with 5g kg-1 of calcium oxide (CaO) or hydroxide [Ca(OH)2]. Eight Holstein cows with 638.01±12.52kg of body weight and milk yield of 20.32±1.5kg d-1 were randomly assigned into two 4x4 Latin squares, fed with the following diets composed of corn silage (CS), fresh sugarcane (FS), sugarcane treated with calcium oxide (STCO) or calcium hydroxide (STCH) as only forage. Data collection lasted five days, after 15 days of adaptation to diets and facilities. The dry matter intake (% of body weight) was higher in diets with CS (3.08) compared to those with FS (2.67), STCO (2.73) or STCH (2.73), which did not differ. Diets with CS determined milk production adjusted for 4% fat (20.05kg d-1) similar to diets containing STCO and STCH (18.01 and 17.89kg d-1, respectively) and higher than those with FS (17.33kg d-1). The experimental diets did not alter the composition of milk. The use of sugarcane treated with Ca(OH)2 is a viable option for feeding Holstein cows with average genetic potential for milk production because it allows production and composition similar to milk dairy cows fed with corn silage, besides benefiting the logistics of feeding in the rural properties.

Performance of early-lactation dairy cows as affected by dietary starch and monensin supplementation

The objective of this study was to evaluate the effect of postpartum dietary starch content and monensin supplementation throughout the periparturient period and into early lactation on production performance of dairy cows during early lactation. Prior to parturition, primiparous (n=21) and multiparous (n=49) Holstein cows were fed a common controlled-energy close-up diet with a daily topdress of either 0 or 400mg/d monensin. From d 1 to 21 postpartum, cows were fed a high-starch (HS; 26.2% starch, 34.3% NDF, 22.7% ADF, 15.5% CP) or low-starch (LS; 21.5% starch, 36.9% NDF, 25.2% ADF, 15.4% CP) total mixed ration with a daily topdress of either 0mg/d of monensin or 450mg/d monensin (MON), continuing with prepartum topdress treatment assignment. From d 22 through 63 postpartum, cows were fed HS and continued with their assigned daily topdress. Interactions of starch content and MON supplementation were not significant for any of the variables measured. Cows fed HS from wk 1 to 3 postpartum had higher early-lactation milk yields (starch × week interaction) compared with LS cows, but HS cows also had lower percentages of milk fat, true protein, lactose, and total solids during the same period, resulting in similar yields of energy-corrected milk (ECM) between starch treatments. Cows fed HS had higher early-lactation dry matter intake (DMI; starch × week interaction) and lost less body condition score during wk 1 to 3, contributing to improved energy balance postpartum. No effect of starch treatment was observed on apparent total-tract dry matter or starch digestibilities assessed during d 18 to 19 (±2) postpartum, although cows fed the LS diet had greater apparent total-tract NDF digestibility compared with cows fed the HS diet. Cows fed MON had higher DMI and higher milk yields during the first 9 wk of lactation. However, all cows had similar yields of ECM because of trends for lower milk fat content during early lactation. In part because of similar yields of ECM between these treatments and higher DMI for cows fed MON, ECM per DMI during the first 9 wk of lactation was not affected by MON treatment. There was no effect of MON treatment on apparent total-tract dry matter, NDF, or starch digestibilities. Overall, cows fed more propiogenic diets in early lactation (HS or MON) had increased milk yield and DMI during the immediate postpartum period, indicating that diets with greater propiogenic capacity do not have detrimental effects on early-lactation DMI.

Effects of partial replacement of dietary starch from barley or corn with lactose on ruminal function, short-chain fatty acid absorption, nitrogen utilization, and production performance of dairy cows

In cows fed diets based on corn-alfalfa silage, replacing starch with sugar improves milk production. Although the rate of ruminal fermentation of sugar is more rapid than that of starch, evidence has been found that feeding sugar as a partial replacement for starch does not negatively affect ruminal pH despite increasing diet fermentability. The mechanism(s) for this desirable response are unknown. Our objective was to determine the effects of replacing barley or corn starch with lactose (as dried whey permeate; DWP) on ruminal function, short-chain fatty acid (SCFA) absorption, and nitrogen (N) utilization in dairy cows. Eight lactating cows were used in a replicated 4×4 Latin square design with 28-d periods and source of starch (barley vs. corn) and level of DWP (0 vs. 6%, DM basis) as treatment factors. Four cows in 1 Latin square were ruminally cannulated for the measurement of ruminal function, SCFA absorption, and N utilization. Dry matter intake and milk and milk component yields did not differ with diet. The dietary addition of DWP tended to increase ruminal butyrate concentration (13.6 vs. 12.2mmol/L), and increased the Cl−-competitive absorption rates for acetate and propionate. There was no sugar effect on minimum ruminal pH, and the duration and area when ruminal pH was below 5.8. Minimum ruminal pH tended to be lower in cows fed barley compared with those fed corn (5.47 vs. 5.61). The duration when ruminal pH was below pH 5.8 tended to be shorter (186 vs. 235min/d), whereas the area (pH×min/d) that pH was below 5.8 was smaller (47 vs. 111) on the corn than barley diets. Cows fed the high- compared with the low-sugar diet had lower ruminal NH3-N concentration. Feeding the high-sugar diet tended to increase apparent total-tract digestibility of dry matter and organic matters and increased apparent total-tract digestibility of fat. Apparent total-tract digestibility of N tended to be greater in cows fed barley compared with those fed corn, whereas apparent total-tract digestibility of acid-digestible fiber was greater in cows fed corn compared with those fed barley. In conclusion, partially replacing dietary corn or barley starch with sugar upregulated ruminal acetate and propionate absorption, suggesting that the mechanisms for the attenuation of ruminal acidosis when sugar is fed is partly mediated via increased SCFA absorption.

Effect of water extract from spent mushroom substrate after Ganoderma balabacense cultivation by using JUNCAO technique on production performance and hematology parameters of dairy cows.

The spent mushroom substrate of Ganoderma balabacense cultivation (SMSGB) contains a large amount of bioactive substances. However, the potentials of SMSGB for improving milk production in dairy cows have not been thoroughly studied. In this study, the effects of hot water extract (HWE) from spent mushroom substrate after G. balabacense cultivated with JUNCAO, the herbaceous plants long-known to be suitable for cultivating edible and medicinal fungi, on production performance and hematology parameters of dairy cows, were determined. Holstein dairy cows were fed different doses of HWE. After a 60-day administration period with 100 g/day of HWE, milk yield, milk protein and triglyceride (TG) levels increased by 4.02% (P < 0.01), 4.49% (P < 0.05) and 32.65% (P < 0.05), respectively; somatic cell count (SCC) and alanine aminotransferase (ALT) were significantly decreased (P < 0.05). The production performance of dairy cows suggests that HWE with SMSGB treatment is effective in improving milk yield (P < 0.01) and hematology parameters of dairy cows, and may be useful as a functional feed additive.

Effect of restricting time at pasture and concentrate supplementation on herbage intake, grazing behaviour and performance of lactating dairy cows

Restricting time for grazing and concentrate supplementation affects feeding motivation, altering grazing behaviour, and performance of grazing ruminants. This study evaluated the combination of three lengths of restricting time at pasture and two levels of concentrate supplementation on behaviour, intake, and productive performance of dairy cows. Times out of pasture were 0, 4 (0800–1200h) and 8.5 (0800–1630h) hours. Levels of concentrate supplementation were 3 and 6kgDM/cow/day. Measurements were: herbage dry matter intake and digestibility, grazing, ruminating and idling time, bite rate, milk yield and composition, as well as changes in live weight and body condition score. Restricting time at pasture increased (P<0.01) grazing time and length of the initial grazing bout (P<0.01) and reduced (P<0.01) rumination and idling times. Restricting time at pasture did not affect herbage intake or milk yield; however, it reduced milk fat concentration (P<0.01). Supplementation level reduced (P<0.05) grazing time, but did not affect rumination and idling times. Bite rate was the greatest in cows that were not restricted and had the lowest level in R8,5S6 groups (P<0.01). Supplementation reduced herbage dry matter intake, and herbage and total organic matter digestibility (P<0.01). Supplementation increased milk yield (P<0.05) without effects on milk composition. Modulation of grazing behaviour in response to restricting time at pasture maintained herbage dry matter intake. Changes in grazing behaviour in response to restricting time at pasture plus concentrate supplementation counteract restrictions of restricted time at pasture and thereby help to maintain herbage and energy intake without negative effects on milk production.

Productive performance of indigenous and HF crossbred dairy cows in Gondar, Ethiopia

Aim: To study the magnitude of variation in lactation length (LL), lactation milk yield (LMY) and peak-yield (PY)due to genetic and non-genetic cases in indigenous and crossbred cattle reared under private dairy unit in and around Gondar, Ethiopia. Materials and Methods: The study was conducted on 411 milch animals from 86 dairy farmers comprising of 172 indigenous and 239 Holstein-Friesian (HF) crossbred cows. These cows were maintained under farmer's management system in and around Gondar (Ethiopia) and were analyzed by Least squares analysis to study the magnitude of variation in their LL, LMY and PY due to genetic and some non-genetic factors. Result: The overall Least squares means for LL, LMY and PY were estimated to be 275.1165.23 days, 1407.3471.34 litres and 6.880.38 litres respectively. Genetic group and lactation order had significant effect (P0.01) on LL, LMY and PY. Season of calving had significant effect (P0.01) on LMY and PY but its effect on LL was non-significant. Effect of location of herd was significant (P0.05) on LMY and PY while its effect on LL was non-significant. Variations in all the traits due to herd size and farming system were statistically non-significant. Conclusion: Productive performance of dairy cows in this study was found to be lesser than the optimum values desirable for profitable milk production.