Third Month Of Lactation Research Articles

Carotenoid Content in Breastmilk in the 3rd and 6th Month of Lactation and Its Associations with Maternal Dietary Intake and Anthropometric Characteristics.

Carotenoids are diet-dependent milk components that are important for the visual and cognitive development of an infant. This study determined β-carotene, lycopene and lutein + zeaxanthin in breastmilk and its associations with dietary intake from healthy Polish mothers in the first six months of lactation. Concentrations of carotenoids in breastmilk were measured by HPLC (high-performance liquid chromatography) (first, third, sixth month of lactation) and dietary intake was assessed based on a three-day dietary record (third and sixth month of lactation). The average age of participants (n = 53) was 31.4 ± 3.8 years. The breastmilk concentrations of carotenoids were not changed over the progress of lactation. Lycopene was a carotenoid with the highest content in breastmilk (first month 112.2 (95% CI 106.1–118.3)—sixth month 110.1 (103.9–116.3) nmol/L) and maternal diet (third month 7897.3 (5465.2–10329.5) and sixth month 7255.8 (5037.5–9474.1) µg/day). There was a positive correlation between carotenoids in breastmilk and dietary intake (lycopene r = 0.374, r = 0.338; lutein + zeaxanthin r = 0.711, r = 0.726, 3rd and 6th month, respectively) and an inverse correlation with maternal BMI in the third month of lactation (β-carotene: r = −0.248, lycopene: r = −0.286, lutein + zeaxanthin: r = −0.355). Adjusted multivariate regression models confirmed an association between lutein + zeaxanthin intake and its concentration in breastmilk (third month: β = 0.730 (0.516–0.943); 6th: β = 0.644 (0.448–0.840)). Due to the positive associations between dietary intake and breastmilk concentrations, breastfeeding mothers should have a diet that is abundant in carotenoids.

Polymorphism identification of Diacylglycerol Acyltransferase1 gene and its correlation with fat content of Saanen goat

Gene markers are often usefull for selection process of cattle on commercial certain phenotypes. Saanen goat has predominance in milk production traits. Milk fat content is one of the commercial traits of milk production. Diacylglycerol Acyltransferase1 (DGAT1) gene was involved in the final process of triglyceride synthesis and associated with milk fat content. Single nucleotide subtitution or insertion-deletion in certain sequence of DGAT1 gene could be gene markers for milk fat content. The objective of this study was to identify differences variation in milk fat content among individual Saanen goats, to identify exon 14-16 polymorphism of DGAT1 gene and to examine its correlation between polymorphism and milk fat content on Saanen goats. The methodologies was collection blood and milk samples, DNA isolation from blood, amplification of DGAT1 genes, sequencing, detection of polymorphism of exon 14-16 DGAT1 gene with Polymerase Chain Reaction-Single Strand Conformation Polymorphism (PCR-SSCP), and examination milk quality on three lactation months using Lactoscan. The average of daily milk production from 70 Saanen goat was 2340±709 mL, 1880±632 mL, 1432±536 mL and average of milk fat content was 3.07±0.52%, 2.53±0.55%, 3.00±0.55% for the first, second and third months of lactation, respectively. The amplicon size of exon 14-16 of DGAT1 gene was ± 350 bp and showed monomorphic pattern from PCR-SSCP. Variation of milk fat content on Saanen goats not caused by polymorphism of exon 14-16 DGAT1 gene.

LACTATION PERFORMANCE OF HIGH-YIELD FIRST-CALF COWS

The results are given from the studies on lactation performance of fi rst-calf cows belonging to different sire lines. The research was conducted in 2017 in Novosibirsk region into 42 fi rst-calf cows of black-andwhite Holstein breed, belonging to the sire lines of Wis Ideal and Refl ection Sovereign, during 150 days of lactation. The pipe-line milking of cows was performed by DeLaval milking machines with adjustable pumping. Monitoring of lactation performance, intensity of milk fl ow, content of fat and protein was carried out monthly. The largest daily milk yield of cows of both lines was noted in the second month of lactation. In the fourth and fi fth months of lactation an average daily milk yield of cows belonging to the Refl ection Sovereign line was higher than that of cows of Wis Ideal line. However, in general, there were no signifi cant differences in lactation performance of cows of these lines. In the second and third months of lactation, cows of both lines had a decrease in the content of fat, protein and intensity of milk fl ow with a gradual increase in these indices in the fourth and fi fth months of lactation. First-calf cows with an average daily yield of 22.9 kg of milk had a higher content of fat and protein (by 0.98 and 0.40% respectively) than cows with an average milk yield of 36.6 kg. It was also noted that with the increase in the level of milk yield there was a tendency for the decrease in the latent period of milk ejection refl ex.

Застосування препарату на основі цитратів Zn та Ge з метою поліпшення показників якості молока-сировини корів

Застосування препарату на основі цитратів Zn та Ge з метою поліпшення показників якості молока-сировини корів

Effect of parity and type of lambing on performance and udder traits of Bandirma ewes

The objective of this study was to evaluate the effect of parity and lambing type on body condition score (BCS), live weight of ewes (LWE), daily milk yield (DMY), lambs growth performance and udder measurement of ewes during first 3 months of lactation in Bandirma ewes. Bandirma ewes (78) with healthy udders and their lambs (117 heads) were used. BCS of ewes was affected significantly by lambing types at first and third months of lactation, while lambing types were not significant in second month of lactation. Parity of ewes did not significantly affected BCS except third month of lactation which was significantly affected by parity. Effects of lambing types and parity of ewes were significant on BCS at first and third month of lactation. Live weight change of ewes was affected significantly by parity, while lambing types were not significant at first 3 months of lactation. There was a significant effect of parity on average daily milk yield at early lactation stage. Also lambing type had significant effect on DMY at first 2 months of lactation. DMY at third month of lactation were not affected by lambing types. Parity affected lambs growth performance in the first three months of lactation. No significant differences between lambing type and parity of ewes in udder measurement, except udder circumference (UC) measure which was significantly affected by parity and lambing types. The effects of parity of ewes were significant on udder circumference and udder width while the other udder traits were not significant. The effects of birth type of ewes were significant on udder width while the other udder traits were not significant. The positive and significant correlations were observed between udder circumference and udder width and daily milk yield in Bandirma sheep. Significant positive phenotypic correlations were determined between lambs live weight (LLW) and LWE, BCS and DMY, LLW and LWE, DMY and LWE. The results suggested that early stage of lactation of ewe’s can be feed supplemented with high energy or high protein for increasing milk production. The control of these physiological stages of ewe may be improved BSC and DMY, also growth performance of lambs. Hence, we recommend that early stage of lactation performance and udder measurements of ewes are to be taken into consideration for selection programme of Bandirma sheep.

Prävalenz von Lahmheiten unterschiedlichen Grades in der Frühlaktation von Milchkühen und deren Einfluss auf Fruchtbarkeitsparameter

To examine the impact of different degrees of lameness on the fertility of dairy cows. Seven dairy herds housed in free stall barns with cubicles were visited at 4-week intervals and all cows were examined for locomotion characteristics using a locomotion scoring system. The cows received scores from 1 (normal gait) to 5 (severely lame). During the study period of 18months, 893 cows in the first month of lactation and 944 cows in the second, third and fourth months of lactation were evaluated. Reproductive measures between non-lame cows (score1), mild lame cows (score2) and cows with clear lameness (score≥3) were compared. Independent of parity and herd effects, cows with scores ≥3 in the first month of lactation displayed a 6days longer calving to first service interval (CFSI) (86.2±35.6 vs. 80.2±34.1 days; p=0.002) and a 16days longer calving to conception interval (CCI) (119.7±51.4 vs. 103.8±55.5 days; p=0.048) than non-lame cows. Additionally, the risk for non-conception was significantly higher in cows suffering from lameness in the first month of lactation (odds ratio: 2.1, 95% confidence interval: 1.095, 4.040; p=0.026). Cows affected by mild lameness in the third month of lactation had a 4 days longer CFSI (84.7± 35.6 vs. 80.1±30.5 days; p=0.026) and a 18 days longer CCI (120.1±55.4 vs. 102.3±47.6 days; p=0.016) than non-lame cows, while the CSFI in distinct lame cows was extended by 7 days compared to non-lame cows (87.2±34.9 vs. 80.1±30.5 days; p=0.002). Cows with the score1 in the first month and score3 in the third month of lactation showed the longest CSFI (94.3±33.9 vs. 76.5± 16.0 days in non-lame cows; p=0.046). This study suggests that both distinct and mild lameness in early lactation lead to a decline in reproduction in dairy herds. A regular determination of the lameness prevalence in dairy herds and optimizing claw health management, including early treatment of lame cows, will enhance animal welfare and reproduction efficiency.

Zmiany zawartości wybranych kwasów tłuszczowych mleka owczego w zależności od miesiąca laktacji

This paper presents the results of an analysis of the composition of sheep milk fatty acids. Milk from Olkuska sheep, Polish mountain sheep, and crossbreeds of Polish mountain sheep and Friesian sheep (75% x 25%) was examined. The fatty acid profiles were analysed according to the month of lactation. Significant differences in fatty acid composition were observed for each breed. In the third and fourth month of lactation, in the milk of crossbreeds and Polish mountain sheep, respectively, saturated fatty acid content significantly decreased while the unsaturated and short-chain saturated fatty acid content increased. In the milk of Olkuska sheep, the content of short-chain saturated fatty acids and saturated fatty acids in the first and third months of lactation was significantly higher, while the content of oleic acid, mono- and polyunsaturated fatty acids was significantly lower than in the second and fourth months. It was also observed that the fatty acid profile of sheep's milk in the first two months of lactation was similar.

Tampilan kualitas susu sapi perah akibat imbangan konsentrat dan hijauan yang berbeda

The aim of this study was to assess the optimal balance ration of concentrate and forage to improve dairy milk production. The research was conducted at regional operational unit Mulyorejo, Barukan village, Tengaran Sub District, Semarang Regency, and Banyu Aji Cooperative, Getasan Sub District, Semarang Regency. Data was analyzed at Feed Nutrition Science Laboratory, Faculty of Animal Husbandry and Agriculture, Diponegoro University Semarang. The research started from June 29 to July 31, 2014. The materials of this research were 12 Friesian Holstein dairy cows in second and third months of lactation with average estimated body weight 408.5±30.86 kg (Coefficient of Variance (CV) = 10.68%) with average milk production around 9.3±1.01 liters (CV = 14.33%). The study was experimental research with completely randomized design using three treatments, i.e. T0 (50% of concentrate and 50% of forage), T1 (45% of concentrate and 55% of forage) and T2 (40% of concentrate and 60% of forage). The results showed that T2 had a significant effect on milk fat content (P<0.05), solid non fat (SNF) content (P<0.05), milk protein content (P<0.01) and milk lactose content (P<0.05). This study concluded that the optimal balance ration of concentrate and forage to improve milk performance consisted of 40% of concentrate and 60% of forage. Keywords : Dairy cow, NDF, milk fat, solid non fat

Maternal intake of fatty acids and their food sources during lactation and the risk of preclinical and clinical type 1 diabetes in the offspring.

We examined maternal dietary intake of fatty acids and foods which are sources of fatty acids during lactation and whether they are associated with the risk of preclinical and clinical type 1 diabetes in the offspring. The subjects comprised a cohort of 2,939 mother-child pairs from the prospective Type 1 Diabetes Prediction and Prevention Study. Composition of maternal diet during the third month of lactation was assessed by a validated food frequency questionnaire. Among the children with HLA-conferred susceptibility to type 1 diabetes, 172 developed preclinical and 81 clinical diabetes. Average follow-up for preclinical type 1 diabetes was 7.5 years (range 0.2-14.0 years) and for clinical type 1 diabetes 7.7 years (0.2-14.0 years). Maternal intake of fatty acids during lactation was not associated with the risk of type 1 diabetes in the offspring. After adjusting for putative confounders, maternal total consumption of red meat and meat products during lactation was associated both with increased risk for preclinical [hazard ratio (HR) 1.19, 95 % CI 1.02-1.40, p = 0.038] and clinical type 1 diabetes (HR 1.27, 95 % CI 1.06-1.52, p = 0.025). In particular, consumption of processed meat products showed an association with increased risk for type 1 diabetes (HR 1.23, 95 % CI 1.02-1.48, p = 0.045). Maternal use of vegetable oils was associated with increased risk for preclinical type 1 diabetes (HR 1.21, 95 % CI 1.03-1.41, p = 0.023). Maternal consumption of red meat, especially processed meat, during lactation may increase the risk of type 1 diabetes.

Relationships of fatty acid group contents in milk and reproductiveperformance in Holstein cows

The aim of this study was to evaluate the relationships between milk fatty acid group contents and subsequent reproductive performance in Holstein cows. A total of 27 cows in the 1st to 4th lactations were included in the evaluation. Cows were divided into primiparous and multiparous groups. Daily milk yields increased in the first 8 weeks of lactation. Body condition score decreased until the third month of lactation. As the cows gradually recovered from the negative energy balance, the contents of saturated fatty acids (SFAs) increased, whereas the contents of monounsaturated fatty acids (MUFAs) and polyunsaturated fatty acids (PUFAs) decreased. The contents of SFAs and MUFAs were significantly (P < 0.01-0.05) correlated (r = -0.279 to r = 0.275) with all the reproductive traits evaluated (calving to first insemination interval, days open, and insemination index). PUFA was only correlated (P < 0.01) with calving to first insemination interval (r = -0.141). High milk SFA contents were associated with improved values of days open and insemination index, whereas opposite tendencies were observed for MUFA. It was concluded that the relationship was confirmed between the changes of different milk fatty acid group contents in early lactation, used as negative energy balance indicators, and subsequent reproduction results.

Udder characteristics and effects of pulsation rate on milking machine efficiency in donkeys

Very little is known about the udder characteristics, partitioning of milk in the mammary gland and efficiency of machine milking in donkeys. This study aimed to evaluate the characteristics of the udder and teats, milk yield in relation to pulsation rates (90, 120 and 150cycles/min), milk partitioning in the mammary gland, composition of the spontaneously removed and residual milk fractions and milking efficiency. Forty-one healthy Martina Franca jennies in the third month of lactation and routinely milked twice daily were used in three studies. Udder characteristics were evaluated by direct measurements and ultrasonographic scanning. Residual milk was obtained by milking after an oxytocin administration (40IU i.m.). The prevalent shapes were 'bowl' for udders and 'conical' for teats. After milking the udder characteristics decreased within a range from -11·6% (udder depth) to -25·7% (diameter of teat at the base). The internal structures of the udder resulted as several pockets of ducts empting directly into the teat. The pulsation rate of 120cycles/min improved (P<0·05) the milk yield in comparison to the 90 and 150cycles/min, reduced the residual milk fraction, thus improved (P<0·05) milking efficiency. Residual milk composition had higher (P<0·05) fat content and somatic cell count than the spontaneously removed milk fraction. The udders revealed several pockets of ducts empting into the teat instead of a single cisternal cavity and showed a certain compliance. The use of 120cycles/min pulsation rate improved milking efficiency.

Study on the possible survival of Staphylococcus chromogenes through the dry period in dairy ewes

CNS (Coagulase-Negative-Staphylococci) in dairy ewes are the most commonly isolated microorganisms during subclinical mastitis and are related to milk loss. The objective of this study was to investigate whether CNS can survive during the dry period, despite the use of drying-off treatment, and persist during the subsequent lactating period in dairy ewes. 47 primiparus dairy Chios ewes were used. All animals were sampled during the last milking before drying-off and they were then randomly assigned into one of two groups. Ewes of the treated group (n=21) were administered a dry period intramammary preparation (Nafpenzal®), and ewes of the control group (n=26) received no drying-off treatment. Immediately after lambing and once every month until the end of lactation, milk samples were collected for microbiological examination and for the determination of SCC. Daily milk yields were also recorded during the sampling days. Twelve out of the total 47 animals were found to carry the same microorganisms during 2 subsequent milking periods (pre and post partum). Staphylococcus chromogenes was the most commonly identified CNS species (7 animals). All 25 isolated Staphylococcus chromogenes strains were subjected to pulsed field gel electrophoreses in order to identify the presence of the same or different clones of the bacteria. Two clones were identified. Both clones were isolated before drying-off and re-isolated during the subsequent lactation period (>90% similarity). Apart from the first month of lactation, mean milk yield of treated group was higher than that of the control group, but the difference was significant only after the third month of lactation (P<0.05). Results from the present study suggest that drying-off treatment is beneficial for milk production, but is not advantageous for the elimination of Staphylococcus chromogenes infections.

Maternal dietary fat and fatty acid intake during lactation and the risk of asthma in the offspring

To explore the association between maternal dietary fat and fatty acid (FA) intake during lactation, and the risk of asthma in the offspring by the age of 5 years. The subjects comprised 1798 mother-child pairs from the Type 1 Diabetes Prediction and Prevention (DIPP) Nutrition Study. Dietary intake was assessed by a validated 181-item food frequency questionnaire, which covered the third month of lactation. The cumulative incidence of asthma was assessed at the age of 5 years with a questionnaire modified from the International Study of Asthma and Allergies in Childhood (ISAAC). Cox proportional hazards regression was used for statistical analysis. The maternal use of margarines during lactation was associated with a marginally increased risk of asthma [hazard ratio (HR) for user vs. nonuser 1.96, 95% confidence interval (CI) 1.01-3.82, p = 0.047] after adjusting for putative confounders. The maternal intakes of n-3 polyunsaturated FA (PUFA) and fish during lactation were not associated with the risk of asthma. Maternal use of margarines during lactation was weakly associated with an increased risk of asthma in the offspring at the age of 5 years. Other fats or FAs during lactation were not associated with the risk of asthma. However, the nonadherence to dietary recommendations regarding especially fats of our study population may restrict the generalizability of our results.

대규모 젖소목장의 임상형 유방염 발생에 관한 후향적 연구

Incidence of mastitis is highest in dairy cows and it is a leader of all diseases and the economic losses, in dairy farms. The objective of this study is to analyse the incidence of clinical mastitis using the lactation number, lactation month and season of calving. In this study, we used 3,779 lactation data and animal health records collected from 1990 to 2006 at the National Institute of Animal Science. Out of 3,779 cows, a total of 1,721 cows were reported with clinical mastitis, which was 46.3%. The frequency of mastitis increased from 36.9% from first lactation to 56.0% by the fifth lactation. As many as 766 cows (46.9%) showed a recurrence of mastitis after 14 days, apart for two or more and chronic mastitis that were recorded for 657 cows (20.3%). This came to a total of 3,010 cases that had clinical mastitis in the herd for sixteen years. The distribution of incidence of clinical mastitis was highest during the first month of lactation at 24.4%, and it reached to 43.4% by the third month. The incidence of mastitis was even higher for cows in first lactation, showing 28.6% in the first month, and 42.9 percent by third month of lactation. Cows calved during the summer and winter months showed higher rate of incidence with 59.9% and 57.9% within 30 days of lactation, respectively. It is urgently needed to establish a preventative management for heifer cows during their expected first lactation and the clinical specific dry-period management strategies that influence the rate of clinical mastitis during the next lactation. The aim of this study is to present information that might be useful to improve clinical mastitis prevention.

A model predicting the seasonal dynamics of intake and production for suckler cows and their calves fed indoors or at pasture

To investigate the dynamics of animal intake and production in grassland-based suckler systems, we constructed a model for suckling cows with their calves. The model calculates on a day-to-day basis the selective intake at pasture and the animal production (weight, condition, milk production) in response to energy intake. The model dynamically applies the feed evaluation systems developed by the INRA: the “cattle fill unit” system to predict forage intake, and the “feed unit” system to predict net energy requirements and supply. To predict intake at pasture, we adapted the cattle fill unit system by adding effects of herbage availability and sward structural composition on the amount and quality of intake. At pasture, the grazeable herbage is divided into structural components characterized by their biomass and digestibility. The model predicts the composition of the diet, assuming that the most digestible and abundant components of herbage are preferred. The amount of herbage ingested depends on the animal profile, the digestibility of the diet and the amount of herbage available. Sward depletion by animal intake at pasture has feedback effects on herbage growth and quality, which can be calculated by a vegetation model. Animal production is calculated based on net energy balance, which is the difference between net energy intake and net energy requirements for maintenance (for cow and calf), gestation and lactation (for the cow). The net energy balance determines weight and condition gain or loss, and – after 3 months of lactation – influences milk production the following day. Changes in weight and condition have feedback effects on energy requirements and intake capacity. Sensitivity analysis on the input values highlighted the importance of forage digestibility for the production of cows and calves. Calf growth was also driven over 3 months old by calf live weight, and under 3 months old by the milk production of the cow. The model's response to stocking rate during the grazing down of a paddock was consistent with current knowledge. The model was validated against experimental data for cows fed indoors or at pasture, at different feed allowances. Model predictions were precise for the digestibility of intake and for live weight (error represents 2–3% of the average observed value), satisfactory for dry matter intake, body condition score and milk production at the beginning of lactation (error represents 10% of the average observed value), and very imprecise for milk production after the third month of lactation (error represents 23% of the average observed value), but the latter had small consequences on calf live weight.

Does maternal docosahexaenoic acid supplementation during pregnancy and lactation lower BMI in late infancy?

We compared growth of infants whose mothers either did or did not receive docosahexaenoic acid (DHA) supplements during pregnancy and lactation. At 21 weeks' gestation, 144 women were enrolled into a randomized, double-blind clinical trial receiving: (1) a basic supplement consisting of vitamins and minerals (BS), or (2) BS plus 4.5 g fructooligosaccharide (BSF), or (3) BSF plus fish oil DHA (200 mg) until the end of the third month of lactation. Infants' length, weight and head circumference were measured at birth and at 1, 3 and 21 months. A total of 51 mothers/infants were lost to follow-up by the third month and 24 at 21 months. The two groups not receiving DHA were combined into a control group. Analysis with mixed models adjusted for confounding factors showed a significant time dependent effect for the DHA group on the development of the body mass index (BMI) (P=0.037), and of weight (P=0.046), but no effect on the development of length (P=0.537), or of head circumference (P=0.267). At 21 months, weight of the DHA group was lower by -601 g (95% CI -171; -1030 g) and BMI was lower by -0.76 kg/m(2) (95% CI -0.07; -1.46) compared to controls. The results indicate that DHA taken by pregnant and lactating mothers may reduce BMI in late infancy.

Influence of increased lipid content in diet in the form of treated rapeseed meal on the metabolism and milk yield of dairy cows in the first third of lactation

The purpose of this study was to evaluate the influence of high lipid concentration in the diet, served as calcium salts of fatty acids from rape, on metabolism and the milk yield of dairy cows during the first third of lactation. 28 dairy cows were divided into experimental (E; n = 14) and control groups (C; n = 14) and monitored within 100 days of lactation since the day of parturition. The diet of both groups had a balanced content of energy and crude protein, while there was a difference in lipid content (C &amp;ndash; 3.7% vs. E &amp;ndash; 6.99% of dry matter in the diet). Blood and urine samples were taken at the end of 1&lt;sup&gt;st&lt;/sup&gt;, 2&lt;sup&gt;nd&lt;/sup&gt; and 3&lt;sup&gt;rd&lt;/sup&gt; months of lactation. Evaluation of milk yield was carried out based on the results of monthly milk yield control, while the evaluation of reproduction was performed using data supplied by a farm livestock specialist. At the end of the first month, a higher degree of energetic metabolism disturbance was determined in group E in comparison with group C (beta-hydroxybutyrate 1.05 vs 0.51 mmol/l, P &amp;le; 0.05; nonesterified fatty acids 0.68 vs. 0.27 mmol/l, P &amp;le; 0.01), as well as a higher occurrence of liver damage (bilirubine 6.50 vs. 4.59 &amp;mu;mol/l, P &amp;le; 0,01; aspartate amino transferase 1.66 vs. 1.39 &amp;mu;kat/l, P&amp;le; 0.05; lactate-dehydrogenase 45.2 vs. 34.3 &amp;mu;kat/l, P &amp;le; 0.05). During the entire experiment, the total concentration of cholesterol, HDL-cholesterol and vitamin E rose, and thus in the 3&lt;sup&gt;rd&lt;/sup&gt; month, the values in the experimental group were almost double that of the control group (cholesterol 7.28 vs. 3.69 mmol/l, P &amp;le; 0.0001; HDL-cholesterol 5.43 vs. 3.26 mmol/l, P &amp;le; 0.0001; vitamin E 19.9 vs. 10.3 &amp;mu;mol/l, P &amp;le; 0.0001). The proportion of HDL-cholesterol was lower in group E (3&lt;sup&gt;rd&lt;/sup&gt; month 76.1 vs. 88.8%, P &amp;le; 0.001). We also determined a higher total anti-oxidant status of serum in group E in the second (0.96 vs. 0.90 mmol/l, P &amp;le; 0.05) and third months of lactation (1.02 vs. 0.94 mmol/l, P&amp;nbsp;&amp;le; 0.05), while other parameters of the anti-oxidation system (glutathionperoxidase, superoxiddismutase) did not differ between groups. The total production of milk within the 100 days of lactation in both monitored groups was similar. In group E the concentration of milk protein was lower (3.18 vs. 3.45%, P &amp;le; 0.01), while the concentration of fat was insignificantly higher (3.55 vs. 3.21%) than in group C. The results of effect on reproduction did not differ significantly either, but the total percentage of gravidity was higher in the experimental group. Our results revealed that feeding of higher doses of lipid (6.99 %) fed in bypass form during the first month after parturition creates the health risk of a fatty liver, but no negative impact on the health of dairy cows was demonstrated during the peak period of lactation.

Effect of Lameness on Culling in Dairy Cows

The purpose of this study was to assess the effect of lameness on dairy cow survival. Cox's proportional hazards regression models were fitted to single-lactation data from 2520 cows in 2 New York State dairy herds. Models were controlled for the time-independent effects of parity, projected milk yield, and calving season, and for the time-dependent effects of lameness and culling. Other common diseases were found to be nonconfounding and so were not included in any of the final models. Survival was measured as the time from calving until death or sale. Cows were censored if they reached the start of the next lactation or end of the study, whichever occurred first. All models were stratified by herd. For all lameness diagnoses combined, survival in the herd decreased for those cows becoming lame during the first half of lactation, with a hazard ratio of up to 2 times that of a nonlame cow. Foot rot diagnosed during the second or third months of lactation decreased survival during the same time period (hazard ratio = 5.1; 95% confidence interval = 1.6 to 16.2). Sole ulcers diagnosed in the first 4 mo of lactation decreased survival in several subsequent periods in which the strongest association was between diagnosis in the third and fourth months of lactation and exit from the herd during that same period (hazard ratio = 2.7; 95% confidence interval = 1.3 to 6.0). Foot warts were not associated with decreased survival in this analysis. Lameness was never associated with increased survival in any of the models.

Food consumption, food passage time, and body measurements of captive Atlantic bottlenose dolphins (&lt;I&gt;Tursiops truncatus&lt;/I&gt;)

The food consumption (recorded as kg of individual fish species), body length, and body mass of 19 (four males and 15 females) Atlantic bottlenose dolphins ( Tursiops truncatus )k ept at Harderwijk Marine Mammal Park, the Netherlands, between 1965 and 1995 are reported. This broad-scale, longitudinal study is based on data originally archived for short-term husbandry purposes. The chemical composition and caloric value of the diet were not measured. Because caloric content of fish varies seasonally and annually, and depends on the geographical region where it was caught, the food intake variations seen in this study may reflect the caloric content of the diet. However, because the e ects of age, gender, and reproductive state are consistent in various animals, and all animals entered the study at di erent times, the e ects are believed to be independent of variation in caloric content of the diet. After weaning, the average annual food consumption of males and nonpregnant, non-lactating females increased rapidly until the estimated age of 3‐5 years, thereafter it averaged around 1900 kg (estimated at 133 # 10 5 kJ) per year. After the age of 20 years, food consumption of several dolphins decreased slightly. Two females reproduced and nursed their calves successfully. Twelve months before parturition, consumption by both ceased almost entirely for one week, probably indicating estrus. Food intake did not increase during pregnancy. After they gave birth, the food consumption of the two mothers showed ac omparable pattern; the food intake remained at ac onsistent level during the month of birth, but increased rapidly in the following month. Food consumption dropped during the third month of lactation in one case and during the fourth month in the other case. During the lactation period, the mothers consumed 2600 kg (48%) and 3300 kg (72%) more than during similar periods in non-reproductive years. The two calves began to eat fish, in addition to suckling, at the ages of 6a nd 19 months respectively. Average standard body length at birth was 116 ’ 6c mf or males (n=15) and 114 ’ 10 cm for females (n=6). It increased rapidly until around the age of 5y ears, after which growth rate declined. Body length reached an asymptote (between 260 and 280 cm) between the ages of 15 and 20 years. Average body mass at birth was 18.0 ’ 3.8 kg for males (n=15) and 15.6 ’ 4.9 kg for females (n=5). Weight gain was rapid until around the age of 3y ears, after which it decreased. The relationship between body mass and standard body length was: Body mass (kg)=12.904e 0.017(body length (cm) 100) . There was an egative relationship between body mass and average daily food consumption expressed as ap ercentage of body mass. The average initial passage time of food through the digestive tract of five animals (with an average body mass of 185 kg) was 235 min.

Relationship Between Teat-End Callosity and Occurrence of Clinical Mastitis

A longitudinal study in 15 herds, with a total of 2157 cows, was conducted to examine the relationship between teat-end callosity (TEC) and the incidence of clinical mastitis. During the 1.5-yr study period, clinical mastitis was diagnosed by the farmers based on clinical signs. Teat-end callosity was scored every month according to a teat-end callosity classification system, which discriminates between teat-end callosity thickness (TECT) and roughness (TECR). Differences in TECT between healthy and clinical mastitis quarters within infected cows were small but significant 3 mo before (0.13 higher), in the month during which the clinical mastitis occurred (0.08 higher), and in the following 2 mo (0.06 and 0.05 higher). To compare TECT and TECR between cows with and without clinical mastitis, 199 cows with clinical mastitis were paired with control cows based on herd, days in milk, and parity. Clinical mastitis cows had more TEC than their healthy herd mates, particularly when clinical mastitis occurred between the second and fifth months of lactation. Clinical Escherichia coli mastitis in the second or third month of lactation occurred in cows with less TEC than in cows with clinical mastitis caused by other pathogens. Clinical culture-negative, yeast, Klebsiella pneumoniae, and Enterobacter aerogenes mastitis cows had more TECT and TECR than other cows with clinical mastitis in the same month of lactation. Pointed teat ends had higher TECT and TECR than flat or inverted teat ends. Teat-end callosity thickness increased with a higher milk yield at peak production.