Dairy Milk Production Research Articles

English

Bovine mastitis is the most costly disease affecting dairy cows and milk production. As Staphylococcus aureus is considered as a major pathogen due to its prevalence in dairy herds, contagious nature of infection, economic impact of treatment and control and its resistance to antimicrobial agents is a well-documented challenge in dairy cows. Therefore, the purpose of this study was to investigate and determine the antibacterial activity of silver nanoparticles against S. aureus isolated from subclinical mastitis cows. The minimum inhibitory concentrations (MIC) distribution of the silver nanoparticles tested for S. aureus field isolates were determined by a broth dilution method. The results show MIC values ranging from 1.25 to 10 μg/ml. The MIC values that inhibited 50 and 90% of the population of the isolates tested of silver nanoparticles were 5 and 10 μg/ml for S. aureus , respectively. In addition, the results of this study demonstrated that the mean time of the antimicrobial action of silver nanoparticles against S. aureus is 7 min. This in vitro result clearly indicates that the silver nanoparticle might have a good activity against S. aureus with mastitis origin. Key words: Bovine mastitis, silver nanoparticles, Staphylococcus aureus.

Effect of biotin on milk performance of dairy cattle: A meta-analysis

A meta-analysis of the effect of biotin on production outcomes of dairy cattle was conducted following a literature review. A total of 11 studies from 9 papers, with information on the milk production and composition data from a total number of 238 cows were extracted and analyzed using meta-analysis software in Stata. Estimated size of effect of biotin was calculated for dry matter intake (DMI), milk production, and composition. Heterogeneity was not significant for all of the parameters (the highest I2=12%). Therefore, fixed effects models were used for analysis. With the addition of biotin to lactating dairy cattle, DMI and milk production increased by 0.87 and 1.66kg/d. No significant effect on percentage of milk fat and milk protein was observed. Additionally, Begg's test indicated no evidence of substantial publication bias for all variables. The influence analysis shows that the removal of any study did not change the direction or significance of the point estimates. It can be concluded that the use of biotin supplements increases DMI and milk yield in lactating dairy cows.

A model of civil society dialogue on dairy business for implementation of milk standards

Turkey has been preparing for the implementation of the common agriculture policy (CAP) in the last four decades. Reaching milk standards is one of the important and difficult components of CAP. Food and agricultural organization (FAO) undertook a milk sector study to review the sector and to provide an analysis of the challenges and constraints in the sector, and the possible measures that would need to be undertaken to prepare Turkey for EU membership. This research was conducted in milk sector in Konya province where there were about 26.226 milk producers and annual milk production was 442, 349 680 L in 2010. The study materials were collected from 4 workshops of dairy and dairy products beneficiaries’ participations in Konya. The workshop methods were moderation techniques. The overall objective is to create a model of civil society dialogue (CSD) on dairy business that can be a guiding model for the other agricultural sub-sectors. Dairy farms, milk production, processing, packaging, and related management functions were analyzed and the implementation of the CSD model for establishing milk standards were drawn as a result of the study. The CSD model which is described in this study may apply for solving related problems of agricultural sub-sectors in developing countries within sub-sector beneficiaries or stockholders. Key words: Dairy business, civil society dialogue, milk standards, Konya.

MASTITE CLÍNICA EM BOVINO CAUSADA POR Prototheca zopfii NO ESTADO DO CEARÁ

We report a case of clinical mastitis caused by Prototheca zopfii (unicellular algae) in the municipality of Iguatu, Ceara. A Holstein cow weighted 500 kg and was 4 years old, with dairy milk production of 18 liters, and was created under intensive system. The main clinical signs observed in the front right quarter, with drop in milk production and presence of flocks in the wired cup test. Two samples of milk were collected from the animals and sent to Laboratorio de Microbiologia Veterinaria at UFERSA. The samples were streaked on Sabouraud agar and incubated under aerobic conditions for 48 hours at 37 o C. After 72 hours the colonies had presented a diameter varying between 3 and 6 mm and irregular edges with central elevation. An antibiogram was also performed, and revealed resistance to all antibiotics tested: getamicin (10mg), chloramphenicol (30 mg), ceftriaxone (30 mg), cefoxitin (30 mg), vancomycin (30 mg), polymyxin (300mg), novobicin (30mg), streptomycin (10mg) and cephalothin (30mg). Keywords: Bovine mastitis, Prototheca, algae, antibiogram.

Influence of digital dermatitis and sole ulcer on dairy cow behaviour and milk production

The aim of the study was to investigate whether the presence of digital dermatitis (DD) and sole ulcer (SU) in dairy cows was associated with changes in behaviour and milk production. Swedish Red and Swedish Holstein cows (mostly in the first to second lactation) were housed in a cubicle system with automatically scraped passageways. After maintenance claw trimming of all the cows in the herd, 10 cows with DD and 10 cows with SU were selected. For each DD- or SU-affected cow, a healthy control cow, matched according to breed, age, parity and lactation stage, was selected. The behaviour of each of the 20 focal cows was observed for 1 h during 2 to 3 weeks after claw trimming (WACT; period 1) and for 1 h during 5 to 6 WACT (period 2). Milk production parameters: energy-corrected milk (ECM), fat and protein percentages and somatic cell counts (SCCs) were recorded once monthly. Lameness was scored once at the start of the study and cows with SU and DD showed more score 2 lameness (42% v. 31%) than the healthy cows (12%). Most differences in behaviour were found during 2 to 3 WACT when DD- and SU-affected cows were lying less (P = 0.001 and P = 0.012, respectively) than healthy cows. Ruminating while standing was performed more in DD-affected cows (P < 0.001) and tended to be performed more in SU-affected cows (P = 0.079) than their controls. Vigilance was performed more in DD- and SU-affected cows than in healthy cows (P < 0.001 and P = 0.047). Cows with DD produced approximately 5.5 kg less ECM per day both at 2 to 3 WACT (P = 0.022) and at 5 to 6 WACT (P = 0.017) than healthy cows, whereas SU-affected cows tended to produce less ECM at 5 to 6 WACT (P = 0.059). No differences in milk fat and protein or SCC were found. It may be concluded that DD-affected cows showed a stronger behavioural response to the claw disease than the SU-affected cows. This shows the importance of regular claw checking and claw trimming of the cows in order to avoid the negative effects on behaviour and milk production.

Reasons for Variations in the Levels of Efficiency in Smallholder Dairy Milk Production in Sri Lanka: A Cross Sectional Data Analysis

In the light of poverty of dairy smallholders and the inability of the Sri Lankan dairy production sector to meet the national demand for dairy milk and milk products, this study looks into why there is a variation in the levels of efficiency achieved by farmers to highlight the policy measures to combat this issue. Using a production frontier, the average levels of efficiency was found to be very low at 52% relative to the most efficient farmer in the sample. This indicates that an efficiency gain of 48% can be achieved if this problem is properly addressed. Identified reasons for this high inefficiency is discussed in detail in this article. Findings suggest that a policy on development of smallholder dairy farming would essentially incorporate the development of veterinary services and knowledge transfer in the producing areas. Keywords: Efficiency; Dairy smallholders DOI: 10.4038/jfa.v1i2.1797 Journal of Food and Agriculture Vol.1(2) 2008 pp.30-39

Research and Findings

NZ Scientists Breakthrough in Dairy Milk Production. IBN Researchers Shine in Biomedical Breakthrough.

The Effect of Roughage Self Sufficiency on Dairy Management and Milk Production

The Effect of Roughage Self Sufficiency on Dairy Management and Milk Production

Effects of feeding increased amounts of wet corn gluten feed on dairy cow metabolism and milk production (2009)

An experiment was conducted to evaluate the effects of feeding increasing dietary amounts of wet corn gluten feed (WCGF). Eight lactating Holstein cows were housed in a tie-stall facility and fed 1 of 4 diets containing 0, 11, 23, or 34% WCGF on a dry matter basis. To maintain similar nutrient concentrations, alfalfa hay, corn silage, corn grain, soybean meal, expeller soybean meal, and mineral supplements varied across diets. Feed intake, milk production, body weight, and body condition score were monitored, and effects of WCGF inclusion rate were assessed. Increasing the level of WCGF in the diet led to increased feed intake, milk production, and body condition. Concentrations of milk components did not differ among treatments; therefore, yield of energy-corrected milk and solids-corrected milk increased as well. In contrast, increasing dietary WCGF decreased efficiency of production and also decreased ruminal pH, possibly because treatments with greater proportions of WCGF had a decreased mean particle size. As expected, the decreased ruminal pH coincided with changes in ruminal volatile fatty acid concentrations. Furthermore, the rate of fiber digestion after 24 hours decreased when more WCGF was incorporated into diets. Results indicate that adding WCGF to dairy rations can increase energy-corrected milk yield, and this increase seems to be driven, at least in part, by an increase in feed intake.

Milk Production Increase in a Dairy Farm under a Six‐Year Brucellosis Control Program

The present work aims to quantify milk production in a bovine dairy herd during a 6-year brucellosis control program in Hidalgo, Mexico, where bovine brucellosis is endemic. This 6-year longitudinal pilot study comprised 74 monthly samplings to determine the incidence of brucellosis and to quantify daily milk production. To determine the monthly incidence of brucellosis, an average of 346 Holstein cows was examined each month with the card and Rivanol tests. These animals had been vaccinated as calves with the normal dose of Brucella abortus RB51 and were revaccinated annually with a reduced dose. Brucellosis is endemic in Mexico, where the control programs include vaccination and diagnosis; nevertheless, it is uncommon to carry out other essential control practices, such as separation and elimination of positive cows. In this herd, the cows positive to the card and rivanol tests were separated in specific units, especially at the moment of delivery. These cows were placed at the end of the line for milking and were eliminated from the herd at the end of their productive cycle. In this dairy herd, cows were milked three times a day and there was a monthly average of 300 cows in production. At the beginning of this study the prevalence of brucellosis was 8.43%; from days 180-330 the incidence was from 0.51% to 0.90%. Between days 360-570, the incidence diminished to 0%; between days 600 to 1140, it increased to 4.46%; and from days 1440 to 2220 the incidence was kept beneath 1%. The average of dairy milk production for each cow per day started with 24 L, increasing in direct proportion to the decrease in the presence of new cases of brucellosis: in the subsequent years, the production increased successively to 25, 27, 28, 29, and 30 L. The daily average per year of milk production in the herd was also quantified: at the beginning of the study it was 7220 L and in subsequent years was 7470, 7710, 8340, 8790, 8970, and 9150 L, respectively. We conclude that a direct relation existed between the application of a program of brucellosis control and the increase in milk production.

White or red clover-grass silage in organic dairy milk production: Grassland productivity and milk production responses with different levels of concentrate

Red (RC) or white (WC) clover were grown in mixture with grasses, ensiled and offered to dairy cows in early lactation over two successive years (48 cows per year) to compare grassland yield, feed intake, milk production and milk quality. The crops were ensiled in round bales and proportional mixtures of the second and third cut prepared each year were used to ensure that the silage treatments were representative of the crop. In addition to silage type, concentrate supplementation, without and with (10 kg/day), was included as a factor in a 2 × 2 factorial, continuous experiment. Total dry matter (DM) yield, silage chemical composition and total DM intake was hardly affected by silage type. There was no effect of silage type on milk yield and milk constituents either, except for higher milk protein content ( P < 0.05) on WC and higher milk fat content of C18:3 n-3 ( P < 0.001), C18:2 n-6 ( P < 0.05) fatty acids (FAs) and sum of polyunsaturated FA ( P < 0.001) and lower n-6/ n-3 FA ratio ( P < 0.01) on RC. Concentrate supplementation increased total DM, N and net energy intakes ( P < 0.001), milk yield ( P < 0.001), milk fat ( P < 0.01) and protein ( P < 0.001) content, decreased the milk urea content ( P < 0.001), and increased the milk fat content of short- and medium-chained FAs (< C16, P < 0.001), C18:0 ( P < 0.01) and C18:2 n-6 ( P < 0.001), decreased the content of C16:0 ( P < 0.05), C18:1 t11 ( P < 0.001) and C18:3 n-3 ( P < 0.001), and increased the n-6/ n-3 FA ratio ( P < 0.001). The effect of concentrate supplementation was not affected by silage type, except for milk protein content where the positive effect of supplementation was stronger on WC than on RC diets ( P < 0.05). This study illustrates that the white- and red clover-grass mixtures investigated were widely similar with regard to their effects on grassland yield, silage intake and milk production and milk constituents, except for a higher milk fat content of C18:3 n-3 and C18:2 n-6 and lower n-6/ n-3 FA ratio on red clover diets. Our findings also show that N conversion efficiency from feed to milk on pure forage diets is more sensitive to changes in dietary protein intake than silage diets containing cereal based concentrates.

The Use of Bulk Tank Milk Samples to Monitor Trends in Antimicrobial Resistance on Dairy Farms

The routine monitoring of bacteria obtained from bulk tank milk (BTM) may be an important tool for detecting farm-level trends in antimicrobial resistance on dairy farms. This study describes and compares antimicrobial susceptibility patterns of Salmonella enterica subspecies enterica (Salmonella) and Escherichia coli recovered from dairy BTM. BTM from more than 400 dairies in a dairy-intense region of California were sampled eight times at 2- to 3-month intervals over a 29-month period. From Salmonella positive and Salmonella negative herds any one Salmonella and three E. coli isolates per sample were tested for susceptibility to 12 antimicrobials. The prevalence of multiple drug resistant (MDR) E. coli was assessed in relation to Salmonella on the farm, farm size, season, MDR Salmonella, and serovar. At each sampling period, 10-21% and 54-77% of the dairy farms were positive for Salmonella and E. coli, respectively. The most commonly recovered Salmonella serovars were Montevideo (33%), Typhimurium (14%), Dublin (13%), and Give (11%). Two-thirds, respectively, of 478 Salmonella and 1577 E. coli isolates were pan-susceptible. The antimicrobial resistance patterns of MDR Salmonella tended to be serovar dependent and were different from the antimicrobial resistance patterns of MDR E. coli. MDR E. coli were more likely to be recovered from dairies with MDR Salmonella. There were no associations between MDR E. coli and season, Salmonella serovar detected in the BTM, or dairy herd size. Bulk milk E. coli and Salmonella could be valuable to monitor the dynamics of antimicrobial resistance in dairy milk production.

Projected change in climate thresholds in the Northeastern U.S.: implications for crops, pests, livestock, and farmers

Most prior climate change assessments for U.S. agriculture have focused on major world food crops such as wheat and maize. While useful from a national and global perspective, these results are not particularly relevant to the Northeastern U.S. agriculture economy, which is dominated by dairy milk production, and high-value horticultural crops such as apples (Malus domestica), grapes (Vitis vinifera), sweet corn (Zea mays var. rugosa), cabbage (Brassica oleracea var. capitata), and maple syrup (sugar maple, Acer saccharum). We used statistically downscaled climate projections generated by the HadCM3 atmosphere–ocean general circulation model, run with Intergovernmental Panel on Climate Change future emissions scenarios A1fi (higher) and B1 (lower), to evaluate several climate thresholds of direct relevance to agriculture in the region. A longer (frost-free) growing season could create new opportunities for farmers with enough capital to take risks on new crops (assuming a market for new crops can be developed). However, our results indicate that many crops will have yield losses associated with increased frequency of high temperature stress, inadequate winter chill period for optimum fruiting in spring, increased pressure from marginally over-wintering and/or invasive weeds, insects, or disease, or other factors. Weeds are likely to benefit more than cash crops from increasing atmospheric carbon dioxide. Projections of thermal heat index values for dairy cows indicate a substantial potential negative impact on milk production. At the higher compared to lower emissions scenario, negative climate change effects will occur sooner, and impact a larger geographic area within the region. Farmer adaptations to climate change will not be cost- or risk-free, and the impact on individual farm families and rural communities will depend on commodity produced, available capital, and timely, accurate climate projections.

Principais métodos de controle e diagnósticos de mastite bovina

Bovine mastitis is a disease with great important for dairy milk production. Adoption of control practices against mastitis promotes significant increment of milk productivity. The present paper reviews the principal methods for diagnostics and control of this disease. Keywords: Mastitis, mammary gland, dairy cattle

Effects of Maturing Stage of Corn Hybrids on Silage Yield, Feeding Value for Dairy Cows and Milk Production in a Cold Region of Japan

This experiment was conducted to evaluate the effects of differently maturing corn hybrids on silage production and milk production per unit area in the northern part of Japan, where grain development occurs under decreasing ambient temperature. Both hybrids were harvested at the same time. The stages of maturity for the early-maturing hybrids (EH; 80 d relative maturity) and the midmaturing hybrids (MH; 93 d relative day) were early dent and late dough stage, respectively. The plant yields for MH were higher than those for EH. The dry matter (DM) content of MH was lower than that for EH, and the effluent loss for MH silage was greater than that for EH silage. Therefore, the DM yields of prepared silage per area were similar for both treatments. Twelve multiparous mid-lactation Holstein cows (58±13 days in milk) were fed diets based on EH or MH silage in a crossover design with two 3-week periods. Cows were fed 3 kg of hay crop silage (DM basis) and either EH or MH silage ad libitum, and concentrates were supplied to meet NRC requirement for dairy cows. Silage DM intake for EH was found to be higher (p<0.05) than that for MH (10.0 vs. 9.1 kg/day). Milk production and milk composition for EH were similar to those for MH. Feed efficiency per total feed intake was similar in both treatments, although the feed efficiency per concentrate intake tended to be higher for the EH than that for the MH diet. These results indicate that differences in maturation in corn hybrids affect the effluent production of silage and the silage intake of dairy cows. It may be advantageous to plant early hybrid corn with a reduction in effluent production of silage as well as a reduction in purchased feed costs for dairy cows under the climatic conditions of the northern part of Japan.

Genetic Parameters For The Somatic Cells Count In The Milk Of Buffaloes UsingOrdinary Test Day Models

The buffaloes dairy milk production (BDMP) has increased in the last 20 years, mainly for the manufacturing of mozzarella cheese, which is recognized by its high nutritional quality. However, this quality can be affected by several factors i. e. high somatic cells count (SCC) provokes changes in the milk’s constituents. As in bovine dairy milk, the SCC is used as diagnostic tool for milk quality; because it enables the diagnosis of sub-clinic mastitis and also allows the selection of individuals genetically resistant to that disease. Based on it, we collected information about SCC and BDMP along the lactation in Murrah breed buffaloes, during the period between 1997 and 2005. Curves were designed to estimate genetic parameters. These parameters were estimated by ordinary test-day models. There were observed variations in the estimated heritability for both characteristics .The lowest score for somatic cells count (SSCC) was seen at first month (0.01) and the highest at sixth months (0.29 The genetic correlation between these traits varied from -1 at the 1 and 9th months to 0.31 and 0.30 in the2 and 4th month of lactation. Phenotypic correlations were all negative (-0.07 in the second month and up to -0.35 in the eighth month of lactation). These results showed that environmental factors are more important than genetics in explain SCC, for this reason, selection for genetic resistance to mastitis in buffalos based in SCC should not be done. In the other hand, negative phenotypic correlations demonstrated that as the SCC increased, the milk production decreased.

Diet and cooling interactions on physiological responses of grazing dairy cows, milk production and composition

The objective of this trial was to evaluate the effects of diet and cooling in the holding pen before milking on rectal temperature, respiration rate and milk production and composition. Fifty-eight lactating Holstein cows were used in a factorial split-plot design, at Rafaela Experimental Station from 12 January to 3 March 2003. The treatments were combinations of two diets: control (CD) and balanced (BD) with two levels of cooling before milking: none (NSF) and a sprinkler and fans (SF). Forage:concentrate ratios for CD and BD were 81:19 and 68:32, respectively. Cows were milked twice daily. Milk production was recorded daily, and milk composition (fat, protein, lactose and urea) was analysed twice a week. The physiological data were recorded once a week, before the cattle entered the holding pen and after milking, in the afternoon. Average maximum weekly temperature humidity index was 75.4 and ranged from 61.4 to 83. There were highly significant effects of cooling on physiological responses. Milk production was affected by diet and cooling, with no interaction; the highest and lowest production of milk was 22.42 and 20.07 l/cow per day, for BD+SF and CD+NSF, respectively. Protein was affected by diet, and was higher for BD (3.17 vs. 3.08%). There were interaction effects on milk fat at the 8% level, the highest concentration being 3.65% for BD+NFS. It was concluded that under grazing conditions, cooling by sprinkler and fans before milking improves the comfort of dairy cows, and that the effects on milk production and composition are enhanced when diets are specially formulated for heat-stress periods.

Occurrence of antibodies to Neospora caninum and Toxoplasma gondii in dairy cattle from the northern region of the Paraná State, Brazil

Three-hundred and eighty-five serum samples were taken from dairy cows on 90 farms in 12 counties from the northern region of the Paraná State, Brazil. The samples were analyzed by IFAT for the detection of anti-Neospora caninum and anti-Toxoplasma gondii IgG antibodies. Forty-five (12%) samples were seropositive to N. caninum, while 102 (26%) samples were seropositive to T. gondii. Only four animals were seropositive to both coccidia. No significant difference was observed between the N. caninum serology and any of the variables studied, such as dairy cattle management, milk production, reproductive problems, feeding, and presence of dogs, cats and rodents. These data suggest that neosporosis is present among dairy cattle in the studied geographic region and the simultaneous detection of serum positive animals to both types of coccidian parasite demonstrates the independent occurrence of these coccidia in dairy cows.

Impact of de-coupling agricultural support on dairy investment and milk production volume in Finland

This study analyses the impacts of de-coupling of agricultural support from production in Finland. A dynamic agricultural sector model, which includes 17 production regions and endogenous investments and technical change, is used in the analysis. Investment in different production techniques is dependent on the relative profitability and the spread of each technique in the population of heterogeneous farms. There are relatively few large farms which use efficient production techniques in Finland. De-coupling weakens the incentive for investment in dairy production and causes a temporary but significant slow down in dairy investments and technical change. Consequently, de-coupling is likely to result in a significant drop in milk and beef production in the next 10–20 year period if no corrective measures are taken in agricultural policy in less-favoured areas such as Finland. However, a slow recovery of investment and output levels are expected in the long run.

HYGIENIC ASPECTS ON FUNGAL CONTAMINATION OF MILKING ENVIRONMENT OF SOME DAIRY FARMS الجوانب الصحية للملوثات الفطرية فى بيئة إنتاج اللبن لبعض مزارع الماشية الحلوب

Dairy environment is an integral part of dairy herd management and milk production. Proper management of herd health involves, preventing animal infection and milk contamination. The present investigation was conducted in three different dairy farms in Assiut Province, included Fac. of Agriculture; Fac. of Vet. Medicine and Secondary School of Agriculture. A total number of 432 random samples (represented by 72 samples of air; 72 wall surfaces swabs; 72 udder and teat surfaces swabs; 54 milker’s hands swabs; 18 teat cups swabs; 72 milk equipments swabs and 72 milk samples) were collected from the milking units of the experimented dairy farms and examined mycologically to evaluate the distribution of pathogenic and potentially pathogenic moulds and yeasts and their role in milk contamination. Variable loads of total mould and yeast counts/unit were detected. Maximum mean count of total moulds and yeasts of 3.52 x10 4 1.26 / m 3 was estimated in air samples, while minimum mean count of 2.6 x10  0.78 / ml was detected in milk samples of the milking stalls of Vet. Medicine Hospital. Maximum of total mould and yeast counts were (6x10 4 / m 3) in air samples of the milking premise of Vet. Medicine Hospital, and (6 x 10 4 / m 2) in inner wall surfaces swabs; (4.2x10 4 / m 2) in udder and teat surfaces swabs in Fac. of Agriculture farm. Minimum of total mould and yeast counts were (0.1x10 / ml) and (0.2x10 / ml) in examined milk sampled from Secondary School of Agricultu re and Fac. of Vet. Medicine farms respectively. Wide varieties of 790 isolates of fungi and yeasts belonged to 13 genera of moulds and yeasts could be isolated from all examined specimens with variable incidence and frequency percentages of major animal and public health significance included Aspergilli (A. flavus; A. fumigatus; A. clavatus; A. glaucus; A. candidum; A. terreus; A. versicolor and A. niger); Cladosporium; Pacilomyces; Mucor; Curvolaria; Trichoderma; Microsporum gypseum; Trichophyton terrestre; Penicillium (P. chrysogenum; P. citrinum; P. funiculosum and P. species); Cladosporum; Fusarium; Alternaria; Demataciae; Rhodotorula; Candida albicans and other mould and yeast species. The obtained results revealed a positive correlation between the load of fungal contamination of milk and contamination loads of its surrounding environment that represented by the high counts of moulds and yeasts in examined milk samples which were also corresponded by high mould and yeast counts of the same pattern in case of examined swabs of the inner wall surfaces; udder and teat surfaces and milker’s hands. The major of animal and public health significance of the isolated mould and yeast