Strategies for Managing Reproduction in the Heat-Stressed Dairy Cowl

P. J. Hansen" and C. F. ArBchiga'y2
*Department of Dairy and Poultry Sciences, University of Florida, Gainesville 3261 1-0920 and
+Facultad de Medicina Veterinaria y Zootecnia, Universidad Autonoma de Zacatecas Zacatecas, Mexico

ABSTRACT

Establishment and maintenance of
pregnancy is difficult in lactating dairy cows exposed
to heat stress because of reductions in estrous
detection rate and the proportion of inseminated cows
that maintain pregnancy. The most common approach
to ameliorate heat stress in developed countries has
been to alter the cow's environment through provision
of shade, fans, sprinklers, and so on. Nonetheless,
seasonal variation in reproductive function persists.
Increased understanding of bovine reproductive function
and its alteration by heat stress has led to
additional strategies for reducing deleterious consequences
of heat stress on reproduction. These include
hormonally induced timed artificial insemination,
which can reduce losses in reproductive efficiency
caused by poor detection of estrus, and embryo
transfer, which can increase pregnancy rate by
allowing embryos to bypass the period when they

are most sensitive to elevated temperature (Le., in the
first 1 to 2 d after breeding).

The effects of bovine viral diarrhoea virus on cattle reproduction in relation to disease control

Abstract

Bovine viral diarrhoea virus (BVDV) is a major reproductive pathogen in cattle. Infection of the bull can lead to a fall in semen quality and the isolation of infectious virus in the ejaculate, while infection in the cow leads to poor conception rates, abortions and congenital defects. BVDV also reduces the animal's resistance to other respiratory and enteric pathogens. The prevalence of BVDV is primarily due to the efficiency with which the virus crosses the placenta of susceptible females. Calves that survive infection during the first trimester of pregnancy are born with a persistent and lifelong infection.

Sıgırlarda Kan Üre Nitrojen Düzeyinin Fertiliteye Etkisi

                                                

                                                 


                                                    Ibrahim AYDIN
Selçuk Üniversitesi, Veteriner Fakültesi, Dogum ve Jinekoloji Anabilim Dalı, Konya-TÜRKIYE


Özet: Yüksek miktarda protein içeren rasyonlarla beslenen ineklerde kan üre nitrojen (BUN) konsantrasyonu artmakta,
artan BUN konsantrasyonu ise fertiliteyi olumsuz olarak etkilemektedir. Sıgırlarda normal BUN konsantrasyonu 12 ile
15 mg/dl arasındadır. BUN konsantrasyonu 19 ile 20 mg/dl’den yüksek olan ineklerde gebelik oranı %20 ile %25 arasında
azalmaktadır. Sıgırlarda yüksek BUN konsantrasyonları ya fertilizasyonda aksamalara ya da erken dönemde
embriyonik ölümlere yol açarak gebelik oranlarını düsürmektedir.

Anahtar Kelimeler: Fertilite, sıgır, üre nitrojen.

Effect of Blood Urea Nitrogen Level on Fertility in Cattle

Summary: Blood urea nitrogen (BUN) concentration increases in cattle fed with dietary including high amount of
protein. However, this increase is associated with decreased fertility. Normal value of BUN in cattle should be between
12-15 mg/dl. If BUN reaches at a level of 19-20 mg/dl, pregnancy rate decreases by 20-25%. It is suggested that high
BUN concentration either leads to failure in fertilization or causes early embryonic deaths.

Key Words: Cattle, fertility, urea nitrogen.

Giris

Ineklerde fertiliteyi etkileyen faktörler genital organlarda
fonksiyonel bozukluklar, enfeksiyonlar,
dogmasal-edinsel anomaliler ve bakım-besleme
gibi çevresel faktörlerdir.

The effect of temperature stress on dairy cows

J. Praks

When environmental temperatures move out of the thermoneutral zone (or comfort zone) dairy cattle begin to experience either heat stress or cold stress. Either stress requires the cow to increase the amount of energy used to maintain the body temperature and there is less energy available to produce milk. Thermoneutral zone is the range of environmental temperatures where normal body temperature is maintained and heat production is at the basal level. The ranges of thermoneutral zone are from lower critical temperature (LCT) to upper critical temperature (UCT). LCT is the environmental temperature at which an animal needs to increase metabolic heat production to maintain body temperature. UCT is the environmental temperature at which the animal increases heat production as a consequence of a rise in body temperature resulting for inadequate evaporative heat loss (Yousef, 1985). Thermoneutral zone depends on the age, breed, feed intake, diet composition, previous state of temperature acclimatization, production, housing and stall conditions, tissue (fat, skin) insulation and external (coat) insulation, and the behaviour of the animal. UCT is given as 25-26 ºC , LCT as a range from -16 to -37 ºC for dairy cows (Berman et al., 1985; Hamada, 1971). LCT for newborn calves is 10 ºC in dry and draught-free environment. LCT decreases to 0 ºC by the time the calf is 1 month old

SIĞIRLARDA ABOMASUM DEPLASMANI VE OPERATİF SAĞALTIMI

*Ali Said DURMUŞ *Emine ÜNSALDI

*Fırat Üniversitesi, Veteriner Fakültesi, Cerrahi Anabilim Dalı-ELAZIĞ


ÖZET
Bu çalışmada sığırlarda abomasum deplasmanlarının tanımlanması, oluşum mekanizması ve sağaltımı ile ilgili kısa bilgiler verilmiş ve kliniğimize gelen olgular üzerinde yapılan çalışmanın sonuçları tartışılmıştır.
Değişik ırk ve yaştaki, toplam 12 adet inekte abomasumun sola deplasmanı (LDA), olgularında sol fossa paralumbalisten, abomasumun sağa deplasmanı (RDA) olgularında ise sağ fossa paralumbalisten laparatomi yapılmış ve abomasopeksi uygulanmıştır. Sekiz adet olguda iyileşme görülürken diğer olgulardan 3 adedi kesime sevk edildi, 1 olgu ise hasta sahibi tarafından zayıfladığı gerekçesiyle kesilmiştir.
Çalışmadan elde edilen sonuçlar, abomasum deplasmanı bulunan olguların, özellikle abomasumun torsiyona uğradığı durumlarda erken şirurjikal girişimle abomasopeksi uygulanarak sağaltılabileceğini göstermektedir.

Anahtar kelimeler: Abomasum deplasmanı, Abomasopeksi, Sığır


ABSTRACT

SURGICAL CORRECTION OF DISPLACED ABOMASUM IN CATTLE

In the current study, brief explanation was given on identification, mechanism of occurence, and treatment of displacement of abomasum, and then, materials, methods and results of the experimental study were discussed.
This study was conducted on 12 cattle with different breed and age. The laparatomy was carried out in the left flank on left displaced abomasum (LDA), and in the right flank on right displaced abomasum (RDA), and abomasopexy was performed in both cases. Eight of the 12 cattle was recovered. Three cases were slaughtered, and one case was slaughtered for lose weight by the owner.
The results showed that early surgical attempts (abomasopexy) were useful in displaced abomasum, particularly torsioned abomasum.