Sandy Sgorlon

Immunomodulatory activity of plant residues on ovine neutrophils

Neutrophils play an essential role in host defense and inflammation. Plants have long been used to improve the immune function, but for most of them specific investigations on animal health are lacking. In the present study, water and hydroethanolic extracts from 11 plant wastes have been screened on immune responses of ovine neutrophils. Eight sheep clinically healthy, not lactating, non-pregnant were selected and used for the experiment. Freshly isolated neutrophils were incubated with the extracts of the residues at increasing doses, and then they were tested for adhesion and superoxide production induced with PMA. The residues of Larix decidua, Thymus vulgaris, Salix alba, Sinupret, Helianthus annuus, Mangifera indica modulated the neutrophil immune functions, moreover, Larix decidua, Thymus vulgaris and Salix alba presented the highest anti-inflammatory activity.

Usefulness of Nutraceutics in Controlling Oxidative Stress in Dairy Cows Around Parturition

Stress often results in the increased production of free radicals in organisms. Recent studies have indicated an interesting relationship between the presence of reactive oxigen species (ROS) and specific cellular activities in the mammary gland of lactating sheep (Colitti et al., 2002), and immunological activity (Kimura et al., 1999) and the ovarian cycle in dairy cows (Trout et al., 1998). An alternative strategy in the control of ROS generation, apart from vitamin E and C administration, is the inclusion in the diet of active compounds such as carotenoids and polyphenols (Jewell and O’Brien, 1999). The role and the activity of natural antioxidants not commonly present in the diets of ruminants (carotenoids and polyphenols of fruits) in the control of ROS generation is an interesting topic to investigate. The aim of this study was to evaluate the effects of dietary administration of nutraceutics with antioxidant properties, in the regulation of cellular redox homeostasis in ruminants.

Oxidative stress indicators and metabolic adaptations in response to the omission of the dry period in dairy cows

The effects of dry period omission on oxidative stress and metabolic indicators around calving were studied. Seventeen Italian Friesian cows were randomly assigned to two groups, homogeneous for milk yield and parity, and managed either with a traditional 55-d dry off period (n=8) or continuously milked till parturition (n=9). Between 60 d before expected calving and 90 d after calving, body condition (BCS) was recorded and blood samples were collected to measure cortisol, urea, cholesterol, glucose, NEFA, triglycerides, insulin, malondialdehyde (MDA), total glutathione (GSH) and glutathione peroxidase (GPx) activity. BCS changes after calving were not different between the two groups. The normally dried group showed lower (P<0.05) glucose concentrations on day 7 before calving, greater (P<0.01) non-esterified fatty acid concentrations at 7 d and 15 d after calving, and greater (P<0.01) triglyceride concentrations for all the period before calving. On the other hand, plasma MDA was not different between groups. On average, plasma GSH concentrations were greater in continuously milked cows after calving (P<0.05), while plasma GPx was greater with continuous milking up to parturition (P<0.01). The results confirmed that omitting the dry period leads to an improved energy balance. The degree of oxidative stress was not detrimental for animal health, and the slight modifications of GPx observed prepartum were possibly related to continuous milk secretion. The differences in plasma GSH observed after calving may depend upon sulphur amino acid sparing in continuously milked cows.

Immune system response to stress factors

Abstract This review highlights fundamental mechanisms of the stress response and important findings as to how the immune system is affected and affects, in turn, such a response. The crucial link between stress response and energy metabolism is dealt with as well. The effector mechanisms in the stress response are remarkably similar for both infectious and non–infectious stimuli, albeit differently modulated. “Psycho-sensitive stimuli/behavioural response” and “Antigenic stimuli/immune response” are indeed two subsystems of a unitary, integrated complex aimed at providing optimal conditions for the host’s survival and adaptation. The interaction between the immune system and the stress/inflammation complex has led to the development of a diversified network of cytokines and chemokines in vertebrate animals. The cytokine response can be mounted in different forms and extent by the host after exposure to both infectious and non-infectious stimuli. In this conceptual framework, microbial infections are just one category of stressing agents, which modulate the cytokine response for a better performance of the innate and adaptive immune responses. The response to infectious and non–infectious stress leads to a metabolic shift that enhances energy, amino acids and micronutrients consumption. The influence of each nutrient on different aspects of immune function is not easy to define, but it is becoming clear that many nutrients have defined roles in the immune response and, accordingly, their requirements are changed to support optimal immune function. Therefore, impairment of immune functions may arise from intakes of nutrients below or above these modified ranges of requirements.

Factors affecting milk cortisol in mid lactating dairy cows

BackgroundWhether the measurement of cortisol in dairy cows can be used as a biomarker of adverse environmental or pathophysiological conditions is still under of scientific debate. In these situations, several systems mainly the hypothalamic-pituitary-adrenal axis, the autonomic nervous system, and the immune system are recruited to reestablish homeostasis. A first aim of the present study was to compare milk and blood cortisol concentrations and to consider its variability in milk in relation to farm, milk yield and days in milk. A second study investigates the effects of breed, class of somatic cell count (SCC) and farm on milk cortisol levels in a larger number of cows and farms, with the aim to validate the results obtained in the pilot study.MethodsFor study 1, 135 cows were sampled from 2 Italian Simmental and 2 Italian Holstein commercial farms, whilst in the second study, 542 cows were sampled from 6 commercial farms of Italian Simmental and 499 cows from 4 commercial farms of Italian Holstein.ResultsIn study 1, the values of cortisol content in milk were significantly higher in Holstein than Simmental cows. Significant differences between farms were observed for milk and plasma cortisol concentrations. Cortisol content in milk was not correlated to plasma content in study 1 and the mean milk to plasma cortisol ratio was about 1:30. In study 2, for Holstein cows, significantly higher values of milk cortisol in comparison to Simmental cows was reported. A significant effect of class of SCC was observed, cows belonging to class 3 (SCC higher than 400.000/ml) showed the highest mean values of milk cortisol. The farm effect was significant also in the study 2, confirming the results obtained in the first study.ConclusionsMilk can be considered a preferential site of sampling in dairy cows to point out short term stimulation of the hypothalamic-pituitary-adrenal axis. Further studies are needed to investigate the physiological basis of the relationship between milk cortisol content and breed, milk yield and SCC to ascertain the relevance of milk cortisol to monitor the healthy status of mammary gland.

Dietary grape poliphenols modulate oxidative stress in ageing rabbits

Riassunto I polifenoli dell’uva regolano lo stress ossidativo nei conigli durante l’invecchiamento. Lo studio ha avuto come obiettivo di verificare gli effetti di un’integrazione alimentare con polifenoli dell’uva sul controllo dello stress ossidativo in conigli durante l’invecchiamento. A tal fine sono stati predisposti 4 gruppi sperimentali che ricevevano diverse concentrazioni giornaliere di polifenoli (CTR: 0 mg/kg di mangime; P1: 0,03 mg/kg; P2: 0,15 mg/kg; P3: 0,30 mg/kg). I prelievi di sangue sono stati effettuati a 1 (T1), 6 (T6) e 10 (T10) mesi dall’inizio della somministrazione dei polifenoli, da settembre 2003 a luglio 2004. Come indicatori di stress sono stati utilizzati il glutatione totale (GSx), il ridotto (GSH) e l’ossidato (GSSG). I livelli di glutatione totale e ridotto sono diminuiti in T6 per poi aumentare nuovamente in T10. I livelli di glutatione ossidato non hanno subito variazioni significative nel tempo. I valori di glutatione totale, ridotto e ossidato hanno mantenuto livelli significativamente più bassi nel gruppo P3 rispetto agli altri gruppi sperimentali. Questi risultati indicano che i polifenoli dell’uva hanno, anche nei conigli, un’azione di regolazione dell’omeostasi ossido-riduttiva.

Productive response of Duroc x Large White and Commercial Hybrid x Large White crosses fed high and low protein diets

Thirty five Duroc x Large White (DUxLW) and 43 Commercial Hybrid x Large White (CHxLW) were fed two diets differing for the content of crude protein (CP), with the aim to evaluate the effects of these diets on growth, carcass and thigh traits. Pigs were allotted to two groups and fed high protein (HP) and low protein (LP) diet. Within each dietary group, 3 diets were formulated, for the initial phase of growth (from 79 to 112 days, 17.3% and 15.4% CP as fed basis for the HP and LP diet, respectively), for the intermediated phase of growth (from 113 to 196 days, 15.1% and 13.7% CP as fed basis for the HP and LP diet, respectively) and for the finishing period (from 197 to 272 days, 13.4% and 11.4% CP as fed basis for the HP and LP diet, respectively). HP diets were supplemented with Lysine, LP were supplemented also with Methionine and Threonine. Pigs were slaughtered at nine months of age. Body weight (BW), average daily gain, total feed intake and feed conversion ratio were not affected by diet. Carcass weight, thigh weight, backfat and lean thickness and lean percentage (Fat-O-Meater, FOM) were not affected by dietary treatments, whilst backfat thickness and FOM were significantly higher (P<0.01) in DUxLW and CHxLW pigs genotype respectively. A reduction of about 15% (12% to 17%) of the dietary CP recommended by nutritional requirements does not affect the main productive performances and carcass characteristics of pigs slaughtered at around 160 kg of BW.

Association of index of welfare and metabolism with the genetic merit of Holstein and Simmental cows after the peak of lactation

The study investigated the relationship of markers of welfare and metabolism in milk, urine and blood with the genetic merit of Holstein and Simmental cows after the peak of lactation. Cows were selected from 3 Simmental (IS) and 2 Holstein (IH) commercial dairy farms. Within each farm, cows were ranked according to the estimated breeding value for milk protein yield (EBVp) from minus to positive and selected every 5 EBVps from minus to positive values (about 20% lactating cows for each farm). Milk was sampled and analysed for protein, fat, lactose, cortisol contents and somatic cell count (SCC). Blood and urines were analysed for biomarkers of metabolism and welfare. Significantly lower body condition score (BCS) was observed for IH in comparison to IS. Plasma creatinine was higher in IS, whilst Zn, total antioxidant status and glutathione peroxidase was higher in IH. The creatinine N to N ratio in urine was significantly higher for IS, while the purine derivatives (PD) N to creatinine N ratio was higher for IH. The EBVp was negatively related to BCS and glucose for IS and to plasma b-hydroxybutyrate in both breeds. EBVp was negatively related to urinary PD N to total N ratios for IS and to PD N to creatinine N ratio for IH. These preliminary results would indicate that the selection of cows for milk protein yield had minor effect on plasma and milk biomarkers of welfare. Instead, biomarkers of metabolism were more affected by breed and genetic merit.

Association analysis between single nucleotide polymorphisms in the promoter region of LEP, MYF6, MYOD1, OPN, SCD genes and carcass traits in heavy pigs

The purpose of the study was to evaluate associations between average daily gain (ADG) and DNA variability in the regulatory region of candidate genes in Italian Large White, Italian Duroc and Italian Landrace breeds for heavy pig production. The ADG of pigs was available as Estimated Breeding Values (EBVs) and Random Residuals (RRs). Within each breed, 200 individuals were sampled, 100 in the higher and 100 in the lower 5% tail of the normal distribution curve according to the EBVs for ADG of the populations (600 pigs overall). Six SNPs in promoter regions of 5 candidate genes (MYF6, MYOD1, OPN, SCD and two for LEP) were analysed. Allele frequencies were calculated and the SNPs for LEP, MYF6 and MYOD1 segregated in the 3 breeds, while polymorphisms in the OPN and SCD genes did not segregate in Italian Large White and Italian Landrace, and Italian Landrace respectively. Fisher’s exact test (two-tailed) for the distribution of allele frequencies in minus and plus variant groups was significant for LEP_1 and MYOD1 in Italian Large White, for LEP_1, LEP_2, MYOD1, OPN and SCD in Italian Duroc and for LEP_1, LEP_2 and MYOD1 in Italian Landrace. Several putative binding sites were detected in the promoter regions using MATINSPECTOR software. Analysed mutations may affect putative core sequences of binding sites for transcription factors involved in muscle and fat tissues deposition. However, variations in binding affinities of the sequences related to the SNPs and the expected differential gene expression require to be evaluated.

Activity of plant wastes on acute phase proteins in cows

Abstract The effect of two patented protected plants wastes (PW), named in the paper as PE and CO, has been evaluated in dairy heifers under ACTH challenge. The experimental protocol used for each compound involved 3 groups of 5 heifers, 18 days of adaptation to the experimental diets and 5 days (22-26) of ACTH treatment (0.5 mg of Synachten – Novartis - twice a day). In addition to the basal diet, 1 kg of a mixture of dehy beet pulp and PW in the ratio of 1.0:0.0 (EXP-0), 0.1:0.9 (EXP-1) and 0.3:0.7 (EXP-2) was fed in the morning meal to the experimental groups. Blood was sampled before (days 19 and 22) and during (days 24 and 26) ACTH treatment and analysed for cortisol, glucose, ceruloplasmin and haptoglobin. Acute phase proteins increased in the EXP-1 group for PE (P<0.01) and in EXP-2 group for CO (P<0.05), while the higher concentration of CO reduced haptoglobin concentration (P=0.01). These results suggest that the efficacy of PW integration is dose dependent and the optimal dose seems to be different between the 2 selected compounds.