Abstract: The objective of this study was to determine the effects of environmental stressors on the performance of lactating dairy cows and discuss some future trends. There exists a relationship between the meteorological data and milk yield prediction accuracy in pasture-based dairy systems. New precision technologies are available and are being developed to improve the sustainability of the dairy industry. Some of these technologies focus on welfare of individual animals on dairy farms. These technologies allow the automatic identification of animal behaviour and health events, greatly increasing overall herd health and yield while reducing animal health inspection demands and long-term animal healthcare costs. The data set consisted of records from 489 dairy cows at two dairy farms and temperature measured from the nearest meteorological weather station in 2018. The effects of temperature on milk production and behaviour of animals were analyzed. The statistical results indicate different effects of temperature on milk yield and behaviour. The “comfort zone” for animals is in the range 10 °C to 20 °C. Dairy cows out of this zone had to decrease or increase their metabolic heat production, and it affected their milk production and behaviour.
Abstract: κ-casein is one of milk proteins which are very important for milk processing. Genotypes of κ-casein affect milk yield, fat, and protein content. The main factors which affect local Latvian dairy breed milk yield and composition are analyzed in research. Data were collected from 88 Latvian brown and 82 Latvian blue cows in 2015. AA genotype was 0.557 in Latvian brown and 0.232 in Latvian blue breed. BB genotype was 0.034 in Latvian brown and 0.207 in Latvian blue breed. Highest milk yield was observed in Latvian brown (5131.2 ± 172.01 kg), significantly high fat content and fat yield also was in Latvian brown (p < 0.05). Significant differences between κ-casein genotypes were not found in Latvian brown, but highest milk yield (5057 ± 130.23 kg), protein content (3.42 ± 0.03%), and protein yield (171.9 ± 4.34 kg) were with AB genotype. Significantly high fat content was observed in Latvian blue breed with BB genotype (4.29 ± 0.17%) compared with AA genotypes (3.42 ± 0.19). Similar tendency was found in protein content – 3.27 ± 0.16% with BB genotype and 2.59 ± 0.16% with AA genotype (p < 0.05). Milk yield increases by increasing parity. We did not obtain major tendency of changes of milk fat and protein content according parity.
Abstract: The age of first calving (AFC) is one of the most important factors that have a significant impact on cow productivity in different lactations and its whole life. A belated AFC leads to reduced reproductive performance and it is one of the main reasons for reduced longevity. Cows that calved in time period from 2001-2007 and in this time finished at least four lactations were included in the database. Data were obtained from 68841 crossbred Holstein Black and White (HM), crossbred Latvian Brown (LB), and Latvian Brown genetic resources (LBGR) cows. Cows were distributed in four groups depending on age at first calving. The longest lifespan was conducted for LBGR cows, but they were also characterized with lowest lifetime milk yield and life day milk yield. HM breed cows had the shortest lifespan, but in the lifespan of 2862.2 days was obtained in average 37916.4 kg milk accordingly 13.2 kg milk in one life day. HM breed cows were also characterized with longer calving intervals (CI) in first four lactations, but LBGR cows had the shortest CI in the study group. Age at first calving significantly affected the length of CI in different lactations (p30 months old in the fourth lactation had the longest CI in all study groups (421.4 days). The LBGR cows were characterized with the shortest CI, but there was slight increase in second and third lactation. Age at first calving had a significant impact on cows’ age in each calving time. In the analysis, cow group was conducted that cows with age at first calving 30 months (932.6 days) at the time of fifth calving were 2560.9 days (7.3 years) old.
Abstract: Three polyvinyl chloride membrane sensors were developed for the electrochemical evaluation of ferrous, manganese and zinc ions. The sensors were used for assaying metal ions in cervical mucus (CM) of Egyptian river buffalo-cows (Bubalus bubalis) as their levels vary dependent on cyclical hormone variation during different phases of estrus cycle. The presented sensors are based on using ionophores, β-cyclodextrin (β-CD), hydroxypropyl β-cyclodextrin (HP-β-CD) and sulfocalix-4-arene (SCAL) for sensors 1, 2 and 3 for Fe2+, Mn2+ and Zn2+, respectively. Dioctyl phthalate (DOP) was used as the plasticizer in a polymeric matrix of polyvinylchloride (PVC). For increasing the selectivity and sensitivity of the sensors, each sensor was enriched with a suitable complexing agent, which enhanced the sensor’s response. For sensor 1, β-CD was mixed with bathophenanthroline; for sensor 2, porphyrin was incorporated with HP-β-CD; while for sensor 3, oxine was the used complexing agent with SCAL. Linear responses of 10-7-10-2 M with cationic slopes of 53.46, 45.01 and 50.96 over pH range 4-8 were obtained using coated graphite sensors for ferrous, manganese and zinc ionic solutions, respectively. The three sensors were validated, according to the IUPAC guidelines. The obtained results by the presented potentiometric procedures were statistically analyzed and compared with those obtained by atomic absorption spectrophotometric method (AAS). No significant differences for either accuracy or precision were observed between the two techniques. Successful application for the determination of the three studied cations in CM, for the purpose to determine the proper time for artificial insemination (AI) was achieved. The results were compared with those obtained upon analyzing the samples by AAS. Proper detection of estrus and correct time of AI was necessary to maximize the production of buffaloes. In this experiment, 30 multi-parous buffalo-cows were in second to third lactation and weighting 415-530 kg, and were synchronized with OVSynch protocol. Samples were taken in three times around ovulation, on day 8 of OVSynch protocol, on day 9 (20 h before AI) and on day 10 (1 h before AI). Beside analysis of trace elements (Fe2+, Mn2+ and Zn2+) in CM using the three sensors, the samples were analyzed for the three cations and also Cu2+ by AAS in the CM samples and blood samples. The results obtained were correlated with hormonal analysis of serum samples and ultrasonography for the purpose of determining of the optimum time of AI. The results showed significant differences and powerful correlation with Zn2+ composition of CM during heat phase and the ovulation time, indicating that the parameter could be used as a tool to decide optimal time of AI in buffalo-cows.
Abstract: To evaluate the effect of intramuscular administration
of vitamin A in pregnant dairy cows during late stages of pregnancy,
on vitamin A status of neonatal calves, a total of 30 cows were
randomly selected and divided into three groups; two treatment
groups and one control group. Single intramuscular injection of
2000000 IU vitamin A; was carried in 10 dairy cows at 7 months of
pregnancy (group 1). In second group of treated animals (10 cows)
the injection was performed in 8 months of pregnancy (group 2). Ten
pregnant dairy cows were received saline injection as placebo and
selected as control group. Blood samples were collected from
experimental dairy cows at 7 and 8 months of pregnancy as well as
their newborn calves’ pre and after colostrum intake. There was no
significant difference between vitamin A and β-carotene
concentration of dairy cows of three groups in two last months of
pregnancy (P> 0.05). Vitamin A concentration of calves of two
treatment groups before and after receiving of colostrum were
significantly higher than that in control group (P< 0.05). There was
no significant difference between serum concentrations of vitamin A
in calves of two treated groups (P> 0.05). β-Carotene concentration
of serum samples of dairy cows and neonatal calves of three groups
were not significantly different as compared with together. From
results of the present study it can be concluded that single injection of
vitamin A during at 7 or 8 month of pregnancy can significantly
increase level of vitamin A in their colostrum and neonatal calves.
Abstract: The objective of this study was to evaluate the
effects of calving season on the production and economic efficiency
of dairy farms in Egypt. Our study was performed at dairy
production farms in the Alexandria, Behera, and Kafr El-Sheikh
provinces of Egypt from summer 2010 to winter 2013. The
randomly selected dairy farms had herds consisting of Baladi,
Holstein-Friesian, or cross-bred (Baladi × Holstein-Friesian) cows.
The data were collected from production records and responses to a
structured questionnaire. The average total return differed
significantly (P < 0.05) between the different cattle breeds and
calving seasons. The average total return was highest for the
Holstein- Friesian cows that calved in the winter (29106.42
EGP/cow/year), and it was lowest for Baladi cows that calved in the
summer (12489.79 EGP/cow/year). Differences in total returns
between the cows that calved in the winter or summer or between
the foreign and native breeds, as well as variations in calf prices,
might have contributed to the differences in milk yield. The average
net profit per cow differed significantly (P < 0.05) between the cattle
breeds and calving seasons. The average net profit values for the
Baladi cows that calved in the winter or summer were 2413 and
2994.96 EGP/cow/year, respectively, and those for the Holstein-
Friesian cows were 10744.17 and 7860.56 EGP/cow/year,
respectively, whereas those for the cross-bred cows were 10174.86
and 7571.33 EGP/cow/year, respectively. The variations in net profit
might have resulted from variation in the availability or price of feed
materials, milk prices, or sales volumes. Our results show that the
breed and calving season of dairy cows significantly affected the
economic efficiency of dairy farms in Egypt. The cows that calved
in the winter produced more milk than those that calved in the
summer, which may have been the result of seasonal influences,
such as temperature, humidity, management practices, and the type
of feed or green fodder available.
Abstract: Stress of slaughter animals starting long before until at the time of process of slaughtering which cause misery and decrease of meat quality. Meanwhile, determination of animal stress using hormonal such as cortisol is expensive and less practical so that portable stress indicator for cows based on Fourier Transform Infrared Spectroscopy (FTIR) must be provided. The aims of this research are to find out the comparison process of slaughter between Rope Casting Local (RCL) and Restraining Box Method (RBM) by measuring of cortisol and wavelength in FTIR methods. Thirty two of male Ongole crossbred cattle were used in this experiment. Blood sampling was taken from jugular vein when they were rested and repeated when slaughtered. All of blood samples were centrifuged at 3000 rpm for 20 minutes to get serum, and then divided into two parts for cortisol assayed using ELISA and for measuring the wavelength using FTIR. The serum then measured at the wavelength between 4000-400 cm-1 using MB3000 FTIR. Band data absorption in wavelength of FTIR is analyzed descriptively by using FTIR Horizon MBTM. For RCL, average of serum cortisol when the animals rested were 11.47 ± 4.88 ng/mL, when the time of slaughter were 23.27 ± 7.84 ng/mL. For RBM, level of cortisol when rested animals were 13.67 ± 3.41 ng/mL and 53.47 ± 20.25 ng/mL during the slaughter. Based on student t-Test, there were significantly different between RBM and RCL methods when beef cattle were slaughtered (P0.05). Result of FTIR with the various of wavelength such as methyl group (=CH3 ) 2986cm-1, methylene (=CH2 ) 2827 cm-1, hydroxyl (- OH) 3371 cm-1, carbonyl (ketones) (C=O) 1636 cm-1, carboxyl (COO-1) 1408 cm-1, glucosa 1057 cm-1, urea 1011 cm-1have been obtained. It can be concluded that the RCL slaughtered method is better than the RBM method based on the increase of cortisol as an indicator of stress in beef cattle (P
Abstract: The objective of this study was to determine effect of
dietary essential oil (EO) compounds, which contained
cinnamaldehyde, eugenol, peppermint, coriander, cumin, lemongrass,
and an organic carrier on feed intake, milk composition, and rumen
fermentation of dairy cows during heat exposure. Thirty-two Holstein
cows (days in milk= 60 ± 5) were assigned to one of two treatment
groups: a Control and EO fed. The experiment lasted 28 days. Dry
matter intake (DMI) was measured daily while and milk production
was measured weekly. Our result showed that DMI and milk yield
was decreased (P < 0.01) in control cows relative to EO cows.
Furthermore, supplementation with EO was associated with a
decrease in the molar proportion of propionate (P < 0.05) and
increase (P < 0.05) in acetate to propionate ratio. In conclusion, EO
supplementations in diets can be useful nutritional modification to
alleviate for the decrease DMI and milk production during heat
exposure in lactating dairy cows.
Abstract: The main goal of this paper was evaluate the effect of
diets containing different levels of probiotic on performance and milk
composition of lactating cows.
Eight Holstein cows were distributed in two 4x4 Latin square. The
diets were based on corn silage, concentrate and the treatment (0, 3, 6
or 9 grams of probiotic/animal/day). It was evaluated the dry matter
intake of nutrients, milk yield and composition.
The use of probiotics did not affect the nutrient intake (p>0.05)
neither the daily milk production or corrected to 4% fat (p>0.05).
However, it was observed that there was a significant fall in milk
composition with higher levels of probiotics supplementation.
These results emphasize the need of further studies with different
experimental designs or improve the number of Latin square with
longer periods of adaptation.
Abstract: The objective of this study was to investigate the lifelong
effect of in utero nutrition fed at different stages of pregnancy in
Bali cows (n = 40): (U1) without in utero nutrition (0 – parturition,
negative control); (U2) 0 – 90 d of gestation; (U3) 90 - 180 d of
gestation; (U4) 180 d – parturition; and (U5) in utero nutrition along
gestation period (0 d to parturition – positive control) on the growth
performance of the offspring to weaning age. The results indicated
that effect of maternal nutrition on male and female offspring were
particularly indicated by the growth performance of both the male
and female offspring from birth to weaning.
Abstract: Mastitis is one of the most economic disease affecting dairy cows worldwide. Its classic diagnosis using bacterial culture and biochemical findings is a difficult and prolonged method. In this research, using of matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) permitted identification of different microorganisms with high accuracy and rapidity (only 24 hours for microbial growth and analysis). During the application of MALDI-TOF MS, one hundred twenty strains of Staphylococcus and Streptococcus species isolated from milk of cows affected by clinical and subclinical mastitis were identified, and the results were compared with those obtained by traditional methods as API and VITEK 2 Systems. 37 of totality 39 strains (~95%) of Staphylococcus aureus (S. aureus) were exactly detected by MALDI TOF MS and then confirmed by a nuc-based PCR technique, whereas accurate identification was observed in 100% (50 isolates) of the coagulase negative staphylococci (CNS) and Streptococcus agalactiae (31 isolates). In brief, our results demonstrated that MALDI-TOF MS is a fast and truthful technique which has the capability to replace conventional identification of several bacterial strains usually isolated in clinical laboratories of microbiology.
Abstract: Corpus luteum cross sectional (by ultrasonography) and plasma progesterone (by DELFIA) were estimated in early pregnant and non pregnant cows on days 14th and 20th to 23rd post insemination. On day 14th, corpus luteum sectional area was 348.43 mm2 in pregnant and 387.84mm2 in non pregnant cows. Within days 20th to 23rd, corpus luteum sectional area ranged between 342.06 and 367.90 mm2 in pregnant and between 193.85 and 270.69 mm2 in non pregnant cows. Plasma progesterone level was 2.43 ng/ml in pregnant and 2.46 ng/ml in non pregnant cows on day 14th, while during days 20th to 23rd the level ranged between 2.47 and 2.84 ng/ml in pregnant and between 0.53 and 1.17 ng/ml in non pregnant cows. Results of both luteal tissue areas as well as plasma progesterone levels were highly significantly deferent (P
Abstract: The object of this study was to investigate several hormones correlated to the reproduction and inhibin A, inhibin B and NO levels in the infertile dairy cows as attempt to illustrate the physiological causes of dairy cows infertility.
40 Holstein cow (21 infertile and 19 fertile) were used at estrous phase of the cycle, Hormones FSH, LH, E2, Testosterone, were measured using ELISA method. inhibin A and B also estimated by ELISA method, Nitric oxide was measured by Greiss reagent method.
The results showed different concentrations of the hormone in which FSH illustrated significantly higher concentration in the infertile cows than fertile cows (P
Abstract: The influence of copper and zinc supplements on milk
production performances and health indicators was tested in a 20-
week feeding trial, with 40 Holstein-Friesian lactating cows, devided
in four groups (copper, zinc, copper-zinc and control). Correlations of
the Cu and Zn plasma values with some animal performance criteria
of health (body condition score and somatic cell counts) and
production (milk yield, peak milk yield, fat and crude protein
content) were done. During the 140 days of the experiment, the two
added minerals caused a statistically significant increase (p < 0.05) of
their plasma values after the peak of the cows’ lactations. It was also
observed that subjects that have received copper and zinc
supplements had the lowest number of somatic cell counts in milk.
The Pearson correlation test showed a positive corellation (p = 0.007,
r = + 0.851) between the plasma Zn and the milk production. The
improvement of the nutritional status improved the milk production
performances of the cows as well as their health performances.
Abstract: The objective of this study was to investigate the effects of dietary supplementation with raw or heat-treated sunflower oil seed with two levels of 7.5% or 15% on unsaturated fatty acids in milk fat and performances of high-yielding lactating cows. Twenty early lactating Holstein cows were used in a complete randomized design. Treatments included: 1) CON, control (without sunflower oil seed). 2) LS-UT, 7.5% raw sunflower oil seed. 3) LS-HT, 7.5% heat-treated sunflower oil seed. 4) HS-UT, 15% raw sunflower oil seed. 5) HS-HT, 15% heat-treated sunflower oil seed. Experimental period lasted for 4 wk, with first 2 wk used for adaptation to the diets. Supplementation with 7.5% raw sunflower seed (LS-UT) tended to decrease milk yield, with 28.37 kg/d compared with the control (34.75 kg/d). Milk fat percentage was increased with the HS-UT treatment that obtained 3.71% compared with CON that was 3.39% and without significant different. Milk protein percent was decreased high level sunflower oil seed treatments (15%) with 3.18% whereas CON treatment is caused 3.40% protein. The cows fed added low sunflower heat-treated (LS-HT) produced milk with the highest content of total unsaturated fatty acid with 32.59 g/100g of milk fat compared with the HS-UT with 23.59 g/100g of milk fat. Content of C18 unsaturated fatty acids in milk fat increased from 21.68 g/100g of fat in the HS-UT to 22.50, 23.98, 27.39 and 30.30 g/100g of fat from the cow fed HS-HT, CON, LS-UT and LS-HT treatments, respectively. C18:2 isomers of fatty acid in milk were greater by LSHT supplementation with significant effect (P < 0.05). Total of C18 unsaturated fatty acids content was significantly higher in milk of animal fed added low heat-treated sunflower (7.5%) than those fed with high sunflower. In all, results of this study showed that diet cow's supplementation with sunflower oil seed tended to reduce milk production of lactating cows but can improve C18 UFA (Unsaturated Fatty Acid) content in milk fat. 7.5% level of sunflower oil seed that heated seemed to be the optimal source to increase UFA production.
Abstract: Twenty - nine Holstein cows were used to evaluate the effects of different dry period (DP) lengths on milk yield and composition, some blood metabolites, and complete blood count (CBC). Cows were assigned to one of 2 treatments: 1) 60-d dry period, 2) 35-d DP. Milk yield, from calving to 60 days, was not different for cows on the treatments (p =0.130). Cows in the 35-d DP produced more milk protein and SNF compare with cows in treatment 1 (p ≤ 0.05). Serum glucose, non-esterified fatty acids (NEFA), beta hydroxyl butyrate acid (BHBA), blood urea nitrogen (BUN), urea, and glutamic oxaloacetic transaminase (GOT) were all similar among the treatments. Body condition score (BCS), body weight (BW), complete blood count (CBC) and health problems were similar between the treatments. The results of this study demonstrated we can reduce the dry period length to 35 days with no problems.
Abstract: Ten lactating multiparous Holstein cows were used in
a cross-over design with two dietary treatments and 28-d periods
(with 14 d as an adaptation) to study the effect of restaurant fat on
milk production and composition. Each cow was offered 14.7 kg
DM /d of the basal concentrate diet based on barley and corn (crude
protein = 17.7%, neutral detergent fiber = 23.5%, and acid detergent
fiber = 5.8% of dry matter) with free access to alfalfa. Dietary
treatments were arranged as supplying each cow with 0 (CONTROL)
or 150 g/day (RF) of restaurant fat. Supplemental RF did not
significantly (P > 0.25) affect milk yield, composition, and
composition yields, except for milk fat contents. Milk fat contents
were depressed (P < 0.05) with supplemental RF. Our results indicate
that RF could depress milk fat without affecting milk yield and that
the depression in milk fat in response to RF precedes the depression
in milk yield.
Abstract: The experiment was then conducted to investigate the
effect of cassava peel addition in the concentrate on the performance
of lactating dairy cows. Twenty four Holstein Friesian crossbred
(>87.5% Holstein Friesian) lactating dairy cows in mid lactation;
averaging 12.2+2.1 kg of milk, 119+45 days in milk, 44.1+6.2
months old and 449+33 kg live weight, were stratified for milk yield,
days in milk, age, stage of lactation and body weight, and then
randomly allocated to three treatment groups. The first, second and
third groups were fed concentrates containing the respective cassava
peel, 0, 20 and 40%. All cows were fed ad libitum corn silage and
freely access to clean water. Dry matter intake, 4%FCM, milk
composition and body weight change were affected (P
Abstract: Forty-five dairy cows were used to compare the
enzyme activity of alkaline phosphatase (ALP), lactate
dehydrogenase (LDH), α -amylase in the cervical mucus of cows
during spontaneous and induced estrus using progestagen or PGF2 α
and to determine whether these enzymes affect the fertility in cows
with induced estrus, at the time of Al. The animals were assigned to 3
groups (no treatment, a Crestar® for 12 days, a double im injection of
PGF2 α). The cows were artificially inseminated (AI). Cervical
mucus samples were collected from all cows 3 to 5 min before the
AI. The results are summarized as follows: ALP and α -amylase
activity for spontaneous estrus were similar to those for induced
estrus (P>0.05) . LDH activity levels during spontaneous and PGF2 α
induced estrus was significantly lower (P < 0.001) than that in
progestagene induced estrus groups. While no difference was found
between the first and the third groups. Our result showed a significant
difference in LDH activity levels between cows conceived with 2 or
more AI and those conceived with 1 AI. The result of this study
showed that the enzyme activity in cervical mucus is helpful for
detection of ovulation and time of AI.
Abstract: The effect of cassava root ensiled with cassava top or
legumes on voluntary feed intake and milk production were
determined in 12 dairy cows using a 4×3 change-over design.
Experimental period were 30 days long and consisted of 14 days of
adaptation. Silage was prepared from cassava root mixed with
cassava top or legumes at ratio 60:40. Cows were allotted at random
to receive ad libitum one of four rations: T1) control, T2) cassava
root +cassava top-silages, T3) cassava root +hamata - silages and T4)
cassava root +Thapra stylo-silages.
The dry matter intake (BW0.75) was higher (P< 0.05) in cow fed
with silages diets compared with T1. However, the intake of T2 was
higher among treatments. Milk production was lowest in cow fed
with T1. Among silages based diets, milk production was not
significantly different but 4%FCM was higher in cow fed T2. Milk
compositions were not affected by feeding diets.
It is concluded that feeding cassava root ensiled with its leaves as
a supplement increased dry matter intake and significantly improved
4%FCM. The combination of cassava root and legume silages did not
improve the feed intake but did increase the milk production.