Paired Somite Counts to Assess the Within-litter Diversity in Embryonic Development at Day 17, 19 and 21 of Pregnancy in Meishan and Yorkshire × Landrace Crossbred Gilts

Contents Eight Meishan and nine Large White × Landrace Crossbred gilts, 7 to 8 months of age, were slaughtered at 17, 19 or 21 days after insemination to determine the within-litter diversity in embryonic development as measured by the number of paired somites as well as by the length and weight of embryos after fixation. Embryonic survival was similar for the two breeds, averaging 85.1 ± 8.5% and 82.8 ± 9.4% for Meishan and Crossbred, respectively. No degenerating embryos were recovered. The normal Meishan and Crossbred embryos were developed similarly at each of the three stages of pregnancy (p ≥ 0.05). The within-litter diversity (s. d.) in the number of somites per embryo was not related to the average number of somites per embryo per litter, nor was it different between breeds. However, the within-litter diversity (s. d.) in the length and weight of embryos increased with increasing average length and weight per embryo per litter, respectively. The increase tended (p < 0.10) to be larger in the Meishan litters. It was concluded that the number of paired somites, the length and the weight of embryos on Days 17, 19 and 21 of pregnancy, give essentially the same information concerning the development of embryos. However, the number of paired somites provides additional information concerning the change in within-litter diversity in embryonic development with increasing average litter development. Inhalt: Unterschiede in der Emryonalentwicklung am 17., 19. und 21. Trächtigkeitstag bei Meishansauen und Yorkshire × Landrasse Kreuzungstieren, gemessen anhand der Anzahl gepaarter Somiten. Jungsauen (acht Meishan- und neun Large White × Landrasse-Kreuzungstiere) im Alter zwischen sieben und acht Monaten wurdem am Tag 17, 19 und 21 nach Besamung geschlachtet, um anhand der Zahl gepaarter Somiten, der Embryolänge und dem Gewicht festzustellen, wie groß die Variation der Embryonalentwicklung innerhalb eines Wurfes ist. Die embryonale Überlebensrate war für beide Rassen (Meishan und Kreuzungsrasse) gleich (im Mittel 85,1 ± 8,5 % und 82,8 ± 9,4%). Degenerierte Embryonen wurden nicht gewonnen. An den Untersuchungstagen entsprachen sie dem erwarteten Entwicklungs-stand (p ≥ 0.05). Die Unterschiede innerhalb des Wurfes (s.d.) hinsichtlich der Somiten-zahlwar nicht mit der durchschnittlichen Somitenzahl pro Embryo pro Wurf korreliert, noch gab es Rasseunterschiede. Bezüglich Größe und Gewicht wurde dagegen eine Zunahme der Variabilität innerhalb des Wurfes bei durchschnittlichem Anstieg dieser beiden Parameter beobachtet. Bei Meishanschweinen schien dies tendenziell deutlicherzu sein (p < 0.10). Daraus läßt sich folgern, daß grundsätzlich ähnliche Aussagen aus det Somitenzahl wie aus Länge und Gewicht der Embryonen am Tag 17, 19, und 21, bestehen. Die Somitenzahl erbringt darüber hinaus noch zusätzliche Znformationen bezüglich der Unterschiede innerhalb des Wurfes.     

Swine dysentery in a sow herd. I. Clinical manifestation and elimination of the disease with a combination of lincomycin and spectinomycin

An acute outbreak of swine dysentery (Doyle) on a farrowing farm is described. Besides clinical signs of enteritis a general loss of condition was seen throughout the herd. This resulted in a decreased fertility and breeding performance among sows and an increase in piglet mortality. Several dehydrated sows aborted. The outbreak was stopped by oral treatment with lincomycin/spectinomycin 1:1. In the course of the treatment all animals and buildings were washed and disinfected. The use of pharmacotherapeutics in treating swine dysentery is discussed with emphasis on the involuntary induction of carriers.     

Characterization of an avian cholera epizootic in wild birds in western Nebraska

Avian cholera killed an estimated 2500 birds in western Nebraska and eastern Wyoming from 28 November 1985 to late January 1986. Wild mallards (Anas platyrhynchos) suffered the most losses. Other wild waterfowl, wild turkeys (Meleagris gallopavo), a few domestic fowl, and a bald eagle (Haliaeetus leucocephalus) also died. Pasteurella multocida serotype 1 was the predominant isolate from these carcasses. Cold, wet weather persisted throughout the outbreak, but daily losses in the flock of 50,000 mallards using the area were low. Pasteurella multocida was isolated from nasal swabs of 35 of 37 cattle from a feedlot in which many of these mallards were feeding. Eighty percent of the cattle isolates had antigenic characteristics of serotype 3 or serotype 3 with cross-reactivity. Isolates from wild mallards, wild turkeys, and the bald eagle were virulent to game-farm mallards when inoculated subcutaneously, but P. multocida isolates from cattle were not.     

Veterinary herd health and production service on dairy farms IV. Index list on calf rearing and cow culling

The Herd Health and Production Service program for use in veterinary dairy practice is comprised of a basic and a flexible system. The basic system is a uniform system of data recording, standard veterinary activities and problem detection. In problem detection 4 index lists play a key role. The 4 comprise of the parameters or index figures that are relevant in monitoring the efficiency of milk production, calf rearing and cow replacement. Data on milk production, health status and reproduction of both individual animals and the herd are collected by the farmer and the veterinarian and transformed into index figures.This paper introduces index list “3”, with index figures for the monitoring of calf rearing and cow culling as parts of a herd health program. The development, implementation and significance of the index figures are presented. The index figures serve to detect unsatisfactory farm situations or problems in calf rearing and in cow culling. They trigger further investigation and aid the solution to and prevention of problems. Relationships with farm parameters mentioned in other index lists are also considered. Objectives and reference values where applicable are provided.     

Effect of l‐glutamic acid supplementation on performance and nitrogen balance of broilers fed low protein diets

The aim of this study was to evaluate the effect of protein reduction and supplementation of l ‐glutamic acid in male broiler diets. A total of 648 chicks of the Cobb 500 strain were distributed in a completely randomized design with six treatments and six replications with eighteen birds per experimental unit. The study comprised pre‐starter (1–7 days), starter (8–21 days), growth (22–35 days) and final (36–45 days) phases. The first treatment consisted of a control diet formulated according to the requirements of essential amino acids for each rearing phase. The second and third treatments had crude protein (CP) reduced by 1.8 and 3.6 percentage points (pp) in relation to the control diet respectively. In the fourth treatment, l ‐glutamic acid was added to provide the same glutamate level as the control diet, and in the last two treatments, the broilers were supplemented with 1 and 2 pp of glutamate above that of the control diet respectively. The reduction in CP decreased the performance of broilers and the supplementation of l ‐glutamic acid did not influence performance when supplied in the diets with excess of glutamate. The lowest excreted nitrogen values were observed in the control diet, and treatments 2 and 3, respectively, in comparison with treatments with the use of l ‐glutamic acid (5 and 6). Retention efficiency of nitrogen was better in the control diet and in the treatment with a reduction of 1.8 pp of CP. It was verified that the serum uric acid level decreased with the CP reduction. A reduction in CP levels of up to 21.3%, 18.8%, 18.32% and 17.57% is recommended in phases from 1 to 7, 8 to 21, 22 to 35 and at 36 to 42 days, respectively, with a level of glutamate at 5.32%, 4.73%, 4.57%, 4.38%, also in these phases.     

Synchronization of estrus by the use of TURISYNCHRON-premix and insemination time in young gilts

In 664 primiparous gilts inseminated twice after oestrus synchronization, the timing of insemination had an important effect on conception rate and litter size. Best results (586 liver piglets per 100 pregnancies) were achieved by a first insemination on the afternoon of the 6th day. Another trial, with sexually mature gilts which were subsequently slaughtered, invloved artificial insemination at a planned time after synchronization of oestus with TRUISYNCHRON plus injection of Prolosan. Pregnancy rate and embryo count on the 29th day after synchronization were good when the first insemination was made on the evening of the 5th day and the second on the evening of the 6th day. Insemination on the morning and evening of the 6th day gave better results than on the evening of the 5th and morning of the 6th day.