Endometrial gene expression in primiparous dairy cows at the end of the voluntary waiting period is affected by nutrition: Total mixed ration vs increasing levels of herbage allowance.

The study postulated that differential nutritional management during the early lactation period would be reflected in endometrial expression of genes related to embryo growth at the end of the voluntary waiting period. Thus, the effect of the combined use of total mixed ration (TMR) and grazing under different herbage allowances during the first 75 days post-partum (DPP) on endometrial gene expression was evaluated in primiparous dairy cows. Cows were blocked by body weight, age and body condition score and randomly assigned to three grazing treatments: high (HA, 30 kg DM per cow per day), medium (MA, 15 kg DM per cow per day) and low (LA, 7.5 kg DM per cow per day) herbage allowance (mixed pasture, 2,600 kg DM per ha) plus 8 kg DM of supplement or TMR (55% forage, 45% concentrate) fed ad libitum (TMR) from calving to 75 DPP. At 57 DPP, cows were synchronized for oestrus (day 0, 68 DPP) and at day 7, endometrial biopsies were obtained. The nutritional treatment did not affect insulin, IGF-1 and leptin concentrations on days 0, 4 or 7. Expression of IGF1, IGFBP3, IGFBP4, ADIPOR1 and ADIPOR2 mRNA was significantly affected by the nutritional treatment. Endometrial IGF1 and IGFBP4 mRNA were twofold greater in TMR and HA than MA and LA cows. Expression of IGFBP3 and ADIPOR1 mRNAs was greater in TMR and HA than MA cows, but did not differ from LA cows. All groups had greater expression of ADIPOR2 mRNA than MA cows. This study provided solid evidence of the importance of nutritional management during early lactation on uterine environment at the end of the voluntary waiting period. The greater expression of genes related to embryo growth and uterine function (IGF system, progesterone and adiponectin receptors) in cows fed diets maximizing energy intake suggests a favourable environment for embryonic growth, which may explain the improved reproductive performance of cows in good energy balance.

Milk casein and fatty acid fractions in early lactation are affected by nutritional regulation of body condition score at the beginning of the transition period in primiparous and multiparous cows under grazing conditions.

The objective was to evaluate the effect of body condition score (BCS) at 30 days before calving (-30 days) induced by a differential nutritional management, parity and week of lactation (WOL) on milk yield and composition, and milk casein and fatty acid composition. Primiparous and multiparous Holstein cows with high BCS (PH, n = 13; MH, n = 9) and low BCS (PL, n = 9; ML = 8) under grazing conditions were sampled at WOL 2 and 8 (before and after peak of lactation). Milk yield was greater in multiparous than in primiparous cows and tended to decrease from WOL 2 to 8 only in ML cows. Milk protein, fat and casein yields were greater in multiparous than in primiparous cows and decreased from WOL 2 to 8. Milk casein concentration in milk protein was greater in MH cows than in ML, PH and PL cows at WOL 2. Milk κ-casein was greater, and ß-casein was less in multiparous than in primiparous cows. As lactation progressed, proportion of casein fractions were not altered. Only κ-casein fraction was affected by BCS at -30 days as PL showed a higher concentration than PH. The de novo (4:0-15:1) and mixed-origin fatty acids (16:0-16:1) in milk fat increased, whereas preformed fatty acids (≥17:0) decreased from WOL 2 to 8. Saturated (SAT) fatty acids tended to be greater and monounsaturated fatty acids (MUFA) were less in multiparous than in primiparous cows. High-BCS cows had greater concentrations of polyunsaturated (PUFA), conjugated linoleic acid (CLA) as well as n-6 and n-3 fatty acids in milk fat than low-BCS cows. The results indicate that casein and fatty acid fractions in milk were affected by parity and may be modified by a differential nutritional management during the pre-calving period (BCS at -30 days) in cows under grazing conditions.

Nutritional regulation of body condition score at the initiation of the transition period in primiparous and multiparous dairy cows under grazing conditions: milk production, resumption of post-partum ovarian cyclicity and metabolic parameters.

The objective of this study was to investigate the effect of different body condition score (BCS) at 30 days before calving (-30 days) induced by a differential nutritional management from -100 days until -30 days on productive parameters, the interval to first ovulation and blood parameters in primiparous and multiparous Holstein cows under grazing conditions until 60 days post partum. The experimental arrangement was a randomized complete block design, where cows were blocked according to BW and expected calving date and then randomly assigned to different nutritional treatments from -100 to -30 days relative to calving to induce different BCS. As the assignment of cows to treatments was random, cows had to lose, maintain or gain BCS; thus, different planes of nutrition were offered with approximately 7, 14 or 20 kg dry matter per day. The BCS score was assessed every 15 days and animals were reassigned in order to achieve the desired BCS at -30 days. Only animals that responded to nutritional treatment were considered and this was defined as follows: primiparous and multiparous high cows (PH and MH) had to gain 0.5 points of BCS, primiparous low (PL) had to lose 0.5 points of BCS and multiparous low (ML) had to maintain BCS at least in two subsequent observations from -100 to -30 days. From -30 days to calving, primiparous and multiparous cows (P and M cows) were managed separately and cows were offered a diet once a day. From calving to 60 days post partum, cows of different groups grazed in separate plots a second year pasture. Cows were also supplemented individually with whole-plant maize silage and commercial concentrate. Cows had similar BCS at -100 days and differed after the nutritional treatment; however, all groups presented similar BCS at 21 days post partum. The daily milk production and milk yield at 60 days post partum was higher in M than P cows. The percentage of milk fat was higher in PH cows compared with PL cows. Concentrations of non-esterified fatty acids (NEFA) were affected by the BCS at -30 days within parity, and in PH cows the concentration of NEFA was higher than in PL cows. The concentrations of total protein were higher in M cows. A lower probability of cycling was found in PL than in PH cows (P < 0.05) and in ML than in MH cows (P < 0.05). Treatment affected various endocrine/metabolic profiles according to parity, suggesting that the metabolic reserves signal the productive/reproductive axis so as to induce a differential nutrient partitioning in adult v. first-calving cows.

Intoxicação por organoclorados (endosulfan) em bovinos no Uruguai / Organochlorine (endosulfan) poisoning in cattle in Uruguay

Descreve-se um surto de intoxicação por organoclorados (Endosulfan) em bovinos ocorrido em abril de 2009, em uma propriedade de recria de bezerros localizada no departamento de Paisandú, Uruguai. O quadro clínico foi observado um dia depois de haver ocorrido na propriedade, uma descarga acidental de 700 litros de um pesticida formulado em solução a base de água mais endosulfan e cipermetrina por dano em um avião pulverizador. A morbidade foi de 7,7 por cento e mortalidade de 6,0 por cento. Os sinais clínicos se caracterizaram por salivação, ataxia, hipersensibilidade, tremores musculares, movimentos de pedalagem, ranger de dentes, excitação, convulsão, decúbito e morte. Na necropsia dos animais e ao exame histopatológico não se observaram lesões. Na mesma propriedade foi observada, também, mortalidade de peixes em um arroio próximo ao local onde o pesticida foi derramado. Amostras de gordura, fígado e conteúdo ruminal de bovinos mortos e de peixes foram analisadas pela técnica de cromatografia gasosa sendo detectada a presença de endosulfan e/ou seus metabólitos em quantidades de 0,16-3,7mg/kg, superiores aos níveis de referência aceitáveis de 0,05-0,2mg/kg, confirmando-se a ocorrência da intoxicação por este organoclorado.

An outbreak of organochlorine (endosulfan) poisoning in cattle registered in April 2009 on a farm for calf rearing is reported. Cattle showed neurological symptoms one day after an accidental discharge of a crop duster releasing 700 liter of pesticide with a water-based solution of endosulfan and cypermethrin had occurred. The morbidity was 7.7 percent and the mortality 6.0 percent. The symptoms in the cattle were sialorrhea, ataxia, hypersensitivity, muscle twitching, pedaling, teeth grinding, excitability, convulsions, recumbency and death. At necropsy of the animals and histopathological examination non significant lesions were found. There was also a significant mortality of fish in the gorge of the affected paddock. Through gas chromatography the presence of endosulfan and/or its metabolite above references levels was identified in samples of fat, liver and rumen contents of affected animals, as well as in fish and water collected, what confirmed the organochlorine poisoning.

[Subacute arsenic poisoning]. / Intoxication suraiguë à l'arsenic.

A cas is reported of a 23-year-old man who voluntarily took a massive dose of arsenic (at least 8 g). In spite of the ingested amount and the acute nature of the poisoning, the patient survived 8 days. Gastrointestinal, neurologic and cardiac features were predominant including nausea, vomiting, choleroid diarrhoea, encephalopathy, peripheral neuropathy, and finally a fatal toxic cardiomyopathy. Metabolic acidosis, moderate cytolysis and an anticoagulant effect were also observed. This unique characteristic was partly due to a circulating anticoagulant with prothrombinase activity, as well as direct antivitamin K activity. Postmortem examination revealed: a congestive oesophagitis; a necrosing gastritis involving all the stomach wall; diffuse hepatic steatosis; skin lesions with vascular congestion and dermoepidermal detachment; discrete subepicardial congestive lesions. Arsenic was found in all tissues.