Condensed tannins fed to dairy goats: effects on digestibility, milk production, blood parameters, methane emission, and energy and nitrogen balances

Condensed tannins (CT) are plant polyphenols that can affect feed digestibility and are potentially able to reduce enteric methane emissions in ruminants. In this in vivo trial with 8 lactating goats, we investigated the effects of 4 levels of inclusion of a commercial CT extract from quebracho (0, 2, 4, 6% on DM basis; C, Q2, Q4, Q6, respectively). The experimental design was a repeated 4 × 4 Latin square with 28-d periods (24 d of diet adaptation and 4 d of sample collection) using metabolic cages and 4 open circuit respiration chambers. The inclusion of CT in the diets did not affect the dry matter intake (DMI) but caused a linear decrease in diet digestibility, with reductions up to -11% for dry matter (DM), -21% for crude protein (CP), -23% for neutral detergent fiber (aNDFom), and -13% for gross energy, when comparing the Q6 and C diets. However, ruminal total volatile fatty acids (VFA) concentration was not affected by CT, although there were changes in VFA proportions. Milk yield (g/d) was highest for Q4 (3371) and lowest for Q6 (3066). In terms of milk composition, CT induced a linear reduction of fat and CP concentrations. The reduction in CP digestibility resulted in a linear reduction in the milk urea level, up to -37% with Q6. Positively, CT linearly reduced the somatic cells count expressed as linear score. The feed efficiency was linearly decreased by CT inclusion. Furthermore, a shift from urinary to fecal nitrogen excretion was observed with CT. The retained nitrogen was always negative (on average -1.93 g/d). The methane yield (on average 19.2 g CH4/kg DMI) was linearly reduced by CT inclusion, up to -18% with Q6. Regarding the CH4 intensity, CT induced a linear reduction when expressed per kg of milk, but not per kg of fat and protein corrected milk. Moreover, the CH4 production per kg of digestible aNDFom was linearly increased by CT. The metabolizable energy intake (MEI) was not affected by the treatments, but the metabolizability (q = MEI/gross energy intake) was reduced as CT inclusion increased. From the results of the present study, it turned out that CT have a negative impact on feed digestibility and feed use efficiency. Condensed tannins can lower CH4 emissions from ruminants; however, the main mechanism of action is likely the decrease in feed digestibility. Furthermore, CT did not improve the N use efficiency. According to these findings, the positive environmental impacts of CT are only related to the shift from urinary to fecal N excretion.

Plasma parameters related to energy and lipid metabolism in periparturient Modenese and Italian Friesian cows

The aim of this work was to compare energy and lipid metabolism during the peripartum period between Modenese (MO) and Italian Friesian (IF) cows. The study was carried out on 33 pluriparous pregnant cows, 19 IF and 14 MO, reared together in the same herd and kept under equal conditions of management and nutrition. Blood was sampled from jugular vein starting 4 week before expected calving date until 4 week post-calving, once weekly. Plasma was analysed for glucose, NEFA, BHBA, triglycerides and cholesterol concentrations. Body condition score (BCS) was assessed weekly after blood sampling. Data from antepartum (a.p.) and post-partum (p.p.) periods were separately analysed as repeated measures by a linear mixed models with the effect of breed, time and their interaction as main factors and random cow within breed. The energy status differed between the two breeds during the peripartum period. We observed higher BCS a.p. and p.p. and lower BCS variations p.p. in MO compared to IF group. Modenese cows showed lower glucose and cholesterol concentrations (p < 0.001), but higher NEFA values, NEFA to cholesterol and NEFA to albumin ratios (p < 0.001) during a.p.; on the contrary, IF cows had higher (p < 0.05) cholesterol, NEFA, BHBA levels and NEFA to albumin ratio than MO ones during p.p. The differences observed between the two breeds suggest how MO cows are subjected to lipid mobilization during late gestation; on the contrary, IF cows are predisposed to mobilize their lipid reserves at the beginning of lactation to support high production. The results indicate a diverse ability to cope with metabolic stress and suggest the hypothesis that the differences in concentrations of plasma parameters and their variation amplitude around the calving period might depend on the different genetic merit for milk production between the two breeds.

Rumination time around calving: an early signal to detect cows at greater risk of disease

The main objective of this experiment was to evaluate the use of rumination time (RT) during the peripartum period as a tool for early disease detection. The study was carried out in an experimental freestall barn and involved 23 Italian Friesian cows (9 primiparous and 14 multiparous). The RT was continuously recorded by using an automatic system (Hr-Tag, SCR Engineers Ltd., Netanya, Israel), and data were summarized in 2-h intervals. Blood samples were collected from 30 d before calving to 42 d in milk (DIM) to assess biochemical indicators related to energy, protein, and mineral metabolism, as well as markers of inflammation and some enzyme activities. The liver functionality index, which includes some negative acute-phase proteins and related parameters (albumin, cholesterol, and bilirubin), was used to evaluate the severity of inflammatory conditions occurring around calving. The cows were retrospectively categorized according to RT observed between 3 and 6 DIM into those with the lowest (L) and highest (H) RT. The average RT before calving (-20 to -2d) was 479 min/d (range 264 to 599), reached a minimum value at calving (30% of RT before calving), and was nearly stable after 15 DIM (on average 452 min/d). Milk yield in early lactation (on average 26.8 kg/d) was positively correlated with RT (r = 0.33). After calving, compared with H cows, the L cows had higher values of haptoglobin (0.61 and 0.34 g/L at 10 DIM in L and H, respectively) for a longer time, had a greater increase in total bilirubin (9.5 and 5.7 μmol/L at 5 DIM in L and H), had greater reductions of albumin (31.2 and 33.5 g/L at 10 DIM in L and H) and paraoxonase (54 and 76 U/ml at 10 DIM in L and H), and had a slower increase of total cholesterol (2.7 and 3.2 mmol/L at 20 DIM in L and H). Furthermore, a lower average value of liver functionality index was observed in L (-6.97) compared with H (-1.91) cows. These results suggest that severe inflammation around parturition is associated with a slower increase of RT after calving. Furthermore, more than 90% of the cows in the L group had clinical diseases in early lactation compared with 42% of the H cows. Overall, our results demonstrate the utility of monitoring RT around calving, and in particular during the first week of lactation, as a way to identify in a timely fashion those cows at a greater risk of developing a disease in early lactation.

Effects of different feeding time and frequency on metabolic conditions and milk production in heat-stressed dairy cows

The aim of this paper was to evaluate the effects of three different feeding management (FM) schedules on physiological markers of heat stress (HS), metabolic conditions, milk yield and quality during the hot season in dairy cows. The study involved 27 mid-lactating cows, subdivided in three homogeneous groups differing in feeding time and frequency: total mixed ration (TMR) delivered once daily in the morning (M); twice daily, half in the morning and half in the evening (ME); once daily in the evening (E). During the trial, blood samples were collected in the morning (a.m.) and in the evening (p.m.), breathing rate (BR), rectal temperature (RT), and milk yield were recorded and individual milk samples were collected. Microclimate data indicated that cows were subjected to mild-moderate HS. During the hotter days, cows receiving M treatment showed higher values of RT (38.97 °C vs 38.68 °C and 38.62 °C, in ME and E) and BR (71.44 vs 66.52 and 65.26 breaths min⁻¹, in ME and E), a.m. plasma glucose was lower in M (3.69 vs 3.83 and 3.83 mmol L⁻¹, in ME and E) and a.m. plasma urea was lower in E (4.82 vs 5.48 and 5.35 mmol L⁻¹, in M and ME). Milk yield was unaffected by FM, as well as milk composition and cheese-making properties. Only milk protein content and yield were higher in M (3.42 vs 3.36 and 3.27 g 100 mL⁻¹; and 1.11 vs 1.08 and 1.02 kg day⁻¹, for ME and E). Our results on cow physiology indicate that M seems a less suitable FM to match cow welfare during the summer season.

Body growth, hematological profile, and clinical biochemistry of heifer calves sired by a bull or its clone

The aim of this paper was to compare body growth, hematological profile development, and clinical biochemistry in the female progeny of a sire with the female progeny of its clone. Sixteen Friesian female calves, 9 daughters from a tested bull (BULL) and 7 from its somatic cell nuclear transfer clone (CLONE) were monitored from birth to 60 wk of life. Body weight (BW), wither height (WH), hip height (HH), body length (BL), and hearth girth (HG) were measured at birth and 4, 8, 12, 16, 20, 24, 36, and 50 wk. Blood samples were taken from jugular vein at 12 to 48 h from birth and 1, 2, 3, 4, 8, 12, 16, 20, 24, and 36 wks of age, to be analyzed for hematological, serum protein, and metabolic profiles. At the same time, rectal temperature (RT) was recorded. Age at puberty was assessed on surviving heifers by measuring weekly plasma progesterone levels. Data were evaluated using a mixed model, taking into account the repeated measures in time on the calf. For each variable, different covariance structures were tested, choosing the best according to the Akaike's Information Criteria. Significant was set at P < 0.05, and a trend was considered for P < 0.10. At 24 wk of age, WH was lower in CLONE daughters than BULL daughters. Around 20 wk of age, there was a trend for lower BW in CLONE daughters than BULL daughters, confirmed from differences in HG. There was no difference in RT due to sire effect. Blood glucose concentration decreased in both groups during the first 4 wk of life; at birth, only a trend for higher blood glucose in CLONE daughters was recorded, whereas an opposite trend was observed for plasma creatinine. Total leukocyte count did not differ between progenies. Circulating lymphocytes tended to be lower in CLONE than BULL daughters. The neutrophil: lymphocyte ratio tended to be higher in CLONE than BULL calves. No difference was demonstrated for erythrocyte features, whereas mean platelet volume tended to be lower in CLONE than BULL progeny. From these results, there were no differences between progenies from BULL and its clone that suggest welfare problems in the first 6 mo of life.

Vitamin and trace element supplementation in grazing dairy ewe during the dry season: effect on milk yield, composition, and clotting aptitude

A study was carried out to evaluate the influence of vitamin and trace mineral supplementation on milk production and composition in grazing dairy ewes during the dry season. Ewes (n = 50) were assigned at weaning to blocks and treatments. Ewes were daily conducted (8 h/day) on a pasture based on Italian ryegrass (Lolium multiflorum). At fold, ewes received a basal diet composed by ad libitum oat hay and a definite amount of a pelleted concentrate. Dietary treatments included: (1) the control concentrate containing background of vitamin and trace mineral only, and (2) the experimental concentrate containing the premix supplement (10 g/kg of dry matter). Vitamin and trace mineral supplementation did not affect ewes' body weight. Milk, fat- and protein-corrected milk, fat percentage, and clotting properties were improved in ewes fed supplemented concentrate. There was a week × treatment interaction (P < 0.05) for yield of milk and corrected milk that was greatest at peak production in ewes fed the premix. Our findings indicate that in grazing dairy ewe, the dietary vitamin and trace mineral supplementation during dry season led to an increase of milk production and quality, with positive improvement in milk clotting aptitude.

Retrospective analyses of m-RNA gene expression profile from formalin fixed paraffin embedded (FFPE) specimens in colorectal cancer (CRC) and correlation with chemoresponsiveness

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Background: Patients with chemoresponsive tumors are more likely to have a survival advantage, consequently a great interest is being placed on the identification of predictive markers. Currently, the improving in the extraction techniques allow the detection of gene profile at the mRNA level from FFPE materials. The purpose of the study was to analyse the m-RNA level of specific genes from FFPE (Stanta et al, BioTechniques 1998), both primary tumor (T) and locoregional lymphnodes (N) in CRC patients treated with chemotherapy (CT), and to relate it with chemoresponsiveness. Material and Methods: RNA was extract from FFPE tumor specimen both in T and N. RNA was reversing transcribed to cDNA. From the cDNA sample, BRCA1, ERCC1, CES2 and TS gene transcripts were specifically amplified by PCR. ERCC1 and BRCA1 are involved in platinum-compound resistance; TS is involved in responses to 5Fluorouracil (5FU) and CES2 level expression was recently related to Irinotecan pro-drug activation. Eligible patients included metastatic CRC patients treated from March 2000 to December 2003 as first line CT with Oxaliplatin/5FU or Irinotecan/5FU or 5FU alone. Results: Forty-five consecutive patients were retrospectively analysed. 15 of them received Oxaliplatin/5FU, 15 Irinotecan/5FU and the other 15 5FU alone. Median age was 64 (range 46–75). 13 patients (28%) had received adjuvant CT. 32 patients (72%) had metastatic disease at the time of surgery. Global Response Rate was 44%. All 45 patients received 5FU and they were analysed for the level of TS expression. With Multiple Regression Analysis, no statistical significant relation between TS level expression and response to 5FU was observed (P=0.36). A strong relation was observed between ERCC1 and response to Oxaliplatin (P=0.006) and a possible correlation of BRCA1-exon11 level expression and response to Irinotecan (P=0.06). The analyses of CES2 and the relation between gene expression and survival are ongoing. Conclusions: The analyses of mRNA gene expression profile from FFPE could be use to predicting response to CT in CRC patients. To test this hypothesis, a randomized phase II-III prospective study of tailored therapy in metastatic CRC is planned.

No significant financial relationships to disclose.

DNA and RNA obtained from Bouin's fixed tissues

BACKGROUND

The use in many countries of acid fixatives, such as Bouin's solution, has limited the use of archival tissue for molecular analysis. An acidic environment is one of the main causes of DNA degradation. Moreover, RNA extraction is difficult in these types of fixed tissues.

AIMS

To amplify DNA and RNA from Bouin's fixed tissues.

METHODS

DNA and RNA were extracted from 20 breast cancer samples that had been routinely fixed in Bouin's fixative. Amplification of several genes using primers that produced amplicons of different lengths was carried out using the polymerase chain reaction (PCR) for DNA (with and without restoration) and reverse transcription PCR for RNA.

RESULTS

The acid environment of Bouin's fixative damaged both DNA and RNA. However, amplification was successful when the amplicon length was reduced to about 80 bp for RNA and 100-200 bp for DNA, especially if submitted to DNA reconstruction procedures.

CONCLUSIONS

It is possible to recover and analyse DNA and RNA from Bouin's fixed and paraffin wax embedded tissues.

PCR analysis in archival postmortem tissues

BACKGROUND

Formalin fixed and paraffin wax embedded tissues of necropsy origin are an important source for molecular analysis especially in rare diseases, neuropathology, or molecular epidemiology studies. Because of DNA degradation, only short sequences can be amplified from this type of tissue, very often less than 100 bases. This poses problems because studies on polymorphism and mutations occurring in large genes often require the analysis of long sequences.

METHODS

The development of a simple treatment to obtain longer fragments of DNA for the analysis of archival postmortem paraffin wax embedded tissues.

RESULTS

It was possible to amplify longer sequences ranging up to 300 bases from postmortem tissues, with no modification to the usual DNA extraction procedures. To obtain longer stretches of DNA, a pre-PCR restoration treatment was required, by filling single strand breaks, followed by a vigorous denaturation step.

CONCLUSIONS

The development of this simple treatment allowed the analysis of longer fragments of DNA obtained from archival postmortem paraffin wax embedded tissues.